Reprogramming Acyl Carrier Protein Interactions of an Acyl-CoA Promiscuous trans-Acyltransferase

DEFF Research Database (Denmark)

Ye, Zhixia; Musiol-Kroll, Ewa Maria; Weber, Tilmann

2014-01-01

Protein interactions between acyl carrier proteins (ACPs) and trans-acting acyltransferase domains (trans-ATs) are critical for regioselective extender unit installation by many polyketide synthases, yet little is known regarding the specificity of these interactions, particularly for trans-ATs w...

Comparative genomics and proteomics of vertebrate diacylglycerol acyltransferase (DGAT), acyl CoA wax alcohol acyltransferase (AWAT) and monoacylglycerol acyltransferase (MGAT).

Science.gov (United States)

Holmes, Roger S

2010-03-01

BLAT (BLAST-Like Alignment Tool) analyses of the opossum (Monodelphis domestica) and zebrafish (Danio rerio) genomes were undertaken using amino acid sequences of the acylglycerol acyltransferase (AGAT) superfamily. Evidence is reported for 8 opossum monoacylglycerol acyltransferase-like (MGAT) (E.C. 2.3.1.22) and diacylglycerol acyltransferase-like (DGAT) (E.C. 2.3.1.20) genes and proteins, including DGAT1, DGAT2, DGAT2L6 (DGAT2-like protein 6), AWAT1 (acyl CoA wax alcohol acyltransferase 1), AWAT2, MGAT1, MGAT2 and MGAT3. Three of these genes (AWAT1, AWAT2 and DGAT2L6) are closely localized on the opossum X chromosome. Evidence is also reported for six zebrafish MGAT- and DGAT-like genes, including two DGAT1-like genes, as well as DGAT2-, MGAT1-, MGAT2- and MGAT3-like genes and proteins. Predicted primary, secondary and transmembrane structures for the opossum and zebrafish MGAT-, AWAT- and DGAT-like subunits and the intron-exon boundaries for genes encoding these enzymes showed a high degree of similarity with other members of the AGAT superfamily, which play major roles in triacylglyceride (DGAT), diacylglyceride (MGAT) and wax ester (AWAT) biosynthesis. Alignments of predicted opossum, zebrafish and other vertebrate DGAT1, DGAT2, other DGAT2-like and MGAT-like amino acid sequences with known human and mouse enzymes demonstrated conservation of residues which are likely to play key roles in catalysis, lipid binding or in maintaining structure. Phylogeny studies of the human, mouse, opossum, zebrafish and pufferfish MGAT- and DGAT-like enzymes indicated that the common ancestors for these genes predated the appearance of bony fish during vertebrate evolution whereas the AWAT- and DGAT2L6-like genes may have appeared more recently prior to the appearance of marsupial and eutherian mammals. Copyright 2009 Elsevier Inc. All rights reserved.

Glycerophosphate/Acylglycerophosphate Acyltransferases

Directory of Open Access Journals (Sweden)

Atsushi Yamashita

2014-11-01

Full Text Available Acyl-CoA:glycerol-3-phosphate acyltransferase (GPAT and acyl-CoA: 1-acyl-glycerol-3-phosphate acyltransferase (AGPAT are involved in the de novo synthesis of triacylglycerol (TAG and glycerophospholipids. Many enzymes belonging to the GPAT/AGPAT family have recently been identified and their physiological or pathophysiological roles have been proposed. The roles of GPAT/AGPAT in the synthesis of TAG and obesity-related diseases were revealed through the identification of causative genes of these diseases or analyses of genetically manipulated animals. Recent studies have suggested that some isoforms of GPAT/AGPAT family enzymes are involved in the fatty acid remodeling of phospholipids. The enzymology of GPAT/AGPAT and their physiological/ pathological roles in the metabolism of glycerolipids have been described and discussed in this review.

Enzymatic characterization of a human acyltransferase activity.

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Akihiko Ozawa

Full Text Available Non-histone protein acylation is increasingly recognized as an important posttranslational modification, but little is known as to the biochemical properties of protein serine acylating enzymes.We here report that we have identified a metal-stimulated serine octanoyltransferase activity in microsomes from human erythroleukemic (HEL cells. The HEL acylating enzyme was linear with respect to time and protein, exhibited a neutral pH optimum (stimulated by cobalt and zinc, and inhibited by chelating reagents. Hydroxylamine treatment removed most, but not all, of the attached radioactivity. A salt extract of microsomal membranes contained the major portion of enzyme activity, indicating that this acyltransferase is not an integral membrane protein. Sucrose density fractionation showed that the acyltransferase activity is concentrated in the endoplasmic reticulum. In competition experiments, the acyltransferase was well inhibited by activated forms of fatty acids containing at least eight to fourteen carbons, but not by acetyl CoA. The zinc-stimulated HEL acyltransferase did not octanoylate proenkephalin, proopiomelanocortin, His-tagged proghrelin, or proghrelin lacking the amino-terminal His-tag stub of Gly-Ala-Met. The peptides des-acyl ghrelin and ACTH were also not acylated; however, des-acyl ghrelin containing the N-terminal tripeptide Gly-Ala-Met was acylated. Mutagenesis studies indicated a requirement for serine five residues from the amino terminus, reminiscent of myristoyl transferase, but not of ghrelin acylation. However, recombinant myristoyl transferase could not recapitulate the hydroxylamine sensitivity, zinc-stimulation, nor EDTA inhibition obtained with HEL acyltransferase, properties preserved in the HEL cell enzyme purified through four sequential chromatographic steps.In conclusion, our data demonstrate the presence of a zinc-stimulated acyltransferase activity concentrated in the endoplasmic reticulum in HEL cells which is likely

Outfoxing the Hedgehog

Science.gov (United States)

Barbieri, Richard

2011-01-01

Jim Collins's "Good to Great" has attained near-scriptural status in organizations, including nonprofits, which Collins says constitute a third of his readers. The pivot point in "Good to Great" is the Hedgehog Concept. The "Hedgehog Concept" (HC), this author claims, is dangerous for schools because it distorts the nature of education. As Collins…

A review of hedgehog signaling in cranial bone development

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Angel ePan

2013-04-01

Full Text Available During craniofacial development, the Hedgehog (HH signaling pathway is essential for mesodermal tissue patterning and differentiation. The Hedgehog family consists of three protein ligands: Sonic Hedgehog (SHH, Indian Hedgehog (IHH, and Desert Hedgehog (DHH, of which two are expressed in the craniofacial complex (IHH and SHH. Dysregulations in HH signaling are well documented to result in a wide range of craniofacial abnormalities, including holoprosencephaly, hypotelorism, and cleft lip/palate. Furthermore, mutations in HH effectors, co-receptors, and ciliary proteins result in skeletal and craniofacial deformities. Cranial suture morphogenesis is a delicate developmental process that requires control of cell commitment, proliferation and differentiation. This review focuses on both what is known and what remains unknown regarding HH signaling in cranial suture morphogenesis and intramembranous ossification. As demonstrated from murine studies, expression of both SHH and IHH is critical to the formation and fusion of the cranial sutures and calvarial ossification. SHH expression has been observed in the cranial suture mesenchyme and its precise function is not fully defined, although some postulate SHH to delay cranial suture fusion. IHH expression is mainly found on the osteogenic fronts of the calvarial bones, and functions to induce cell proliferation and differentiation. Unfortunately, neonatal lethality of deficient mice precludes a detailed examination of their postnatal calvarial phenotype. In summary, a number of basic questions are yet to be answered regarding domains of expression, developmental role, and functional overlap of HH morphogens in the calvaria. Nevertheless, SHH and IHH ligands are integral to cranial suture development and regulation of calvarial ossification. When HH signaling goes awry, the resultant suite of morphologic abnormalities highlights the important roles of HH signaling in cranial development.

Indian Hedgehog Suppresses a Stromal Cell-Driven Intestinal Immune Response

NARCIS (Netherlands)

Westendorp, B. Florien; Büller, Nikè V. J. A.; Karpus, Olga N.; van Dop, Willemijn A.; Koster, Jan; Versteeg, Rogier; Koelink, Pim J.; Snel, Clinton Y.; Meisner, Sander; Roelofs, Joris J. T. H.; Uhmann, Anja; Ver Loren van Themaat, Emiel; Heijmans, Jarom; Hahn, Heidi; Muncan, Vanesa; Wildenberg, Manon E.; van den Brink, Gijs R.

2018-01-01

Upon intestinal epithelial damage a complex wound healing response is initiated to restore epithelial integrity and defend against pathogenic invasion. Epithelium-derived Indian Hedgehog (Ihh) functions as a critical sensor in this process. Signaling occurs in a paracrine manner because the receptor

Detection of a pneumonia virus of mice (PVM) in an African hedgehog (Atelerix arbiventris) with suspected wobbly hedgehog syndrome (WHS).

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Madarame, Hiroo; Ogihara, Kikumi; Kimura, Moe; Nagai, Makoto; Omatsu, Tsutomu; Ochiai, Hideharu; Mizutani, Tetsyuya

2014-09-17

A pneumonia virus of mice (PVM) from an African hedgehog (Atelerix arbiventris) with suspected wobbly hedgehog syndrome (WHS) was detected and genetically characterized. The affected hedgehog had a nonsuppurative encephalitis with vacuolization of the white matter, and the brain samples yielded RNA reads highly homogeneous to PVM strain 15 (96.5% of full genomic sequence homology by analysis of next generation sequencing). PVM antigen was also detected in the brain and the lungs immunohistochemically. A PVM was strongly suggested as a causative agent of encephalitis of a hedgehog with suspected WHS. This is a first report of PVM infection in hedgehogs. Copyright © 2014 Elsevier B.V. All rights reserved.

[Progress in the study on diacylgycerol acyltransferase (DGAT)-related genes].

Science.gov (United States)

Ma, Hai-Ming; Shi, Qi-Shun; Liu, Xiao-Chun

2005-12-01

Diacylgycerol Acyltransferase (DGAT) plays an important role in the formation of lipid in different tissues of biological body. DGAT catalyzes the final step in triacylglycerol (TAG) biosynthesis by converting diacylgycerol (DAG) and fatty acyl-coenzyme A (CoA) into triacylglycerol. This enzyme is coded by both DGAT1 and DGAT2. DGAT1 belongs to the gene family of cholesterol acyltransferase (ACAT). DGAT2 belongs to the gene family of monoacylgycerol acyltransferases (MGAT1). This paper reviewed the structure, location on chromosome and biological effect of DGAT-related genes. The relationship between polymorphism and performance of animal was also discussed.

Sarcoptes scabiei on hedgehogs in New Zealand.

Science.gov (United States)

Kriechbaum, Caroline; Pomroy, William; Gedye, Kristene

2018-03-01

European hedgehogs (Erinaceus europaeus) were introduced into New Zealand from Britain during the period from 1869 to the early 1900s. The only mite found on New Zealand hedgehogs in early studies was Caparinia tripilis, with Sarcoptes scabiei first being reported in 1996. The aim of this study was to investigate the prevalence of Sarcoptes infestation on hedgehogs in New Zealand, the number of mites found and the degree of mange observed. Dead hedgehogs were collected from veterinary clinics, rescue centres, members of the public and from road-kill. Twenty-one (55.3%) of the animals examined had visible skin lesions. Both Caparinia and Sarcoptes mites were identified on microscopic examination with Sarcoptes the most common, being found on over 70% of animals examined (n = 38). The numbers of mites recovered after brushing the head and body ranged from 1 to 5659 (median = 341 mites) with only six animals (22.2%) having fewer than 10 Sarcoptes mites found. Caparinia mites were seen on fewer animals and generally in very low numbers. These findings indicate a change in the mite populations on hedgehogs in New Zealand and that infected animals develop the debilitating hyperkeratotic form of sarcoptic mange without an accompanying hypersensitivity response limiting numbers of mites. Analysis of the cox 1 gene of Sarcoptes from two hedgehogs showed close alignment to sequences derived from a pig with one and from a dog with the second. More work needs to be undertaken to identify the source(s) of the Sarcoptes found on hedgehogs in New Zealand and whether other mammalian hosts may be infected from contact with hedgehogs.

Hedgehog signaling and therapeutics in pancreatic cancer.

LENUS (Irish Health Repository)

Kelleher, Fergal C

2012-02-01

OBJECTIVE: To conduct a systematic review of the role that the hedgehog signaling pathway has in pancreatic cancer tumorigenesis. METHOD: PubMed search (2000-2010) and literature based references. RESULTS: Firstly, in 2009 a genetic analysis of pancreatic cancers found that a core set of 12 cellular signaling pathways including hedgehog were genetically altered in 67-100% of cases. Secondly, in vitro and in vivo studies of treatment with cyclopamine (a naturally occurring antagonist of the hedgehog signaling pathway component; Smoothened) has shown that inhibition of hedgehog can abrogate pancreatic cancer metastasis. Thirdly, experimental evidence has demonstrated that sonic hedgehog (Shh) is correlated with desmoplasia in pancreatic cancer. This is important because targeting the Shh pathway potentially may facilitate chemotherapeutic drug delivery as pancreatic cancers tend to have a dense fibrotic stroma that extrinsically compresses the tumor vasculature leading to a hypoperfusing intratumoral circulation. It is probable that patients with locally advanced pancreatic cancer will derive the greatest benefit from treatment with Smoothened antagonists. Fourthly, it has been found that ligand dependent activation by hedgehog occurs in the tumor stromal microenvironment in pancreatic cancer, a paracrine effect on tumorigenesis. Finally, in pancreatic cancer, cells with the CD44+CD24+ESA+ immunophenotype select a population enriched for cancer initiating stem cells. Shh is increased 46-fold in CD44+CD24+ESA+ cells compared with normal pancreatic epithelial cells. Medications that destruct pancreatic cancer initiating stem cells are a potentially novel strategy in cancer treatment. CONCLUSIONS: Aberrant hedgehog signaling occurs in pancreatic cancer tumorigenesis and therapeutics that target the transmembrane receptor Smoothened abrogate hedgehog signaling and may improve the outcomes of patients with pancreatic cancer.

NHR-23 dependent collagen and hedgehog-related genes required for molting

International Nuclear Information System (INIS)

Kouns, Nathaniel A.; Nakielna, Johana; Behensky, Frantisek; Krause, Michael W.; Kostrouch, Zdenek; Kostrouchova, Marta

2011-01-01

Highlights: → NHR-23 is a critical regulator of nematode development and molting. → The manuscript characterizes the loss-of-function phenotype of an nhr-23 mutant. → Whole genome expression analysis identifies new potential targets of NHR-23. → Hedgehog-related genes are identified as NHR-23 dependent genes. → New link between sterol mediated signaling and regulation by NHR-23 is found. -- Abstract: NHR-23, a conserved member of the nuclear receptor family of transcription factors, is required for normal development in Caenorhabditis elegans where it plays a critical role in growth and molting. In a search for NHR-23 dependent genes, we performed whole genome comparative expression microarrays on both control and nhr-23 inhibited synchronized larvae. Genes that decreased in response to nhr-23 RNAi included several collagen genes. Unexpectedly, several hedgehog-related genes were also down-regulated after nhr-23 RNAi. A homozygous nhr-23 deletion allele was used to confirm the RNAi knockdown phenotypes and the changes in gene expression. Our results indicate that NHR-23 is a critical co-regulator of functionally linked genes involved in growth and molting and reveal evolutionary parallels among the ecdysozoa.

NHR-23 dependent collagen and hedgehog-related genes required for molting

Energy Technology Data Exchange (ETDEWEB)

Kouns, Nathaniel A.; Nakielna, Johana; Behensky, Frantisek [Laboratory of Model Systems, Institute of Inherited Metabolic Disorders, First Faculty of Medicine, Charles University, Prague (Czech Republic); Krause, Michael W. [Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD (United States); Kostrouch, Zdenek [Laboratory of Model Systems, Institute of Inherited Metabolic Disorders, First Faculty of Medicine, Charles University, Prague (Czech Republic); Kostrouchova, Marta, E-mail: marta.kostrouchova@lf1.cuni.cz [Laboratory of Model Systems, Institute of Inherited Metabolic Disorders, First Faculty of Medicine, Charles University, Prague (Czech Republic)

2011-10-07

Highlights: {yields} NHR-23 is a critical regulator of nematode development and molting. {yields} The manuscript characterizes the loss-of-function phenotype of an nhr-23 mutant. {yields} Whole genome expression analysis identifies new potential targets of NHR-23. {yields} Hedgehog-related genes are identified as NHR-23 dependent genes. {yields} New link between sterol mediated signaling and regulation by NHR-23 is found. -- Abstract: NHR-23, a conserved member of the nuclear receptor family of transcription factors, is required for normal development in Caenorhabditis elegans where it plays a critical role in growth and molting. In a search for NHR-23 dependent genes, we performed whole genome comparative expression microarrays on both control and nhr-23 inhibited synchronized larvae. Genes that decreased in response to nhr-23 RNAi included several collagen genes. Unexpectedly, several hedgehog-related genes were also down-regulated after nhr-23 RNAi. A homozygous nhr-23 deletion allele was used to confirm the RNAi knockdown phenotypes and the changes in gene expression. Our results indicate that NHR-23 is a critical co-regulator of functionally linked genes involved in growth and molting and reveal evolutionary parallels among the ecdysozoa.

Gravitational black-holes-hedgehogs and two degenerate vacua of the Universe

Science.gov (United States)

Sidharth, B. G.; Das, C. R.; Laperashvili, L. V.; Nielsen, H. B.

In the present paper, assuming the Multiple Point Principle (MPP) as a new law of Nature, we considered the existence of the two degenerate vacua of the Universe: the first Electroweak (EW) vacuum at v1 ≈ 246GeV — “true vacuum”, and the second Planck scale “false vacuum” at v2 ˜ 1018 GeV. In these vacua, we investigated different topological defects. The main aim of this paper is an investigation of the black-hole-hedgehogs configurations as defects of the false vacuum. In the framework of the f(R) gravity, described by the Gravi-Weak unification model, we considered a black-hole solution, which corresponds to a “hedgehog” — global monopole, that has been “swallowed” by the black-hole with mass core MBH ˜ 1018GeV and radius δ ˜ 10‑21GeV‑1. Considering the results of the hedgehog lattice theory in the framework of the SU(2) Yang-Mills gauge-invariant theory with hedgehogs in the Wilson loops, we have used the critical value of temperature for the hedgehogs confinement phase (Tc ˜ 1018GeV). This result gave us the possibility to conclude that the SM shows a new physics with contributions of the SU(2)-triplet Higgs bosons at the scale ˜10TeV. Theory predicts the stability of the EW-vacuum and the accuracy of the MPP.

Sox11 is required to maintain proper levels of Hedgehog signaling during vertebrate ocular morphogenesis.

Directory of Open Access Journals (Sweden)

Lakshmi Pillai-Kastoori

2014-07-01

Full Text Available Ocular coloboma is a sight-threatening malformation caused by failure of the choroid fissure to close during morphogenesis of the eye, and is frequently associated with additional anomalies, including microphthalmia and cataracts. Although Hedgehog signaling is known to play a critical role in choroid fissure closure, genetic regulation of this pathway remains poorly understood. Here, we show that the transcription factor Sox11 is required to maintain specific levels of Hedgehog signaling during ocular development. Sox11-deficient zebrafish embryos displayed delayed and abnormal lens formation, coloboma, and a specific reduction in rod photoreceptors, all of which could be rescued by treatment with the Hedgehog pathway inhibitor cyclopamine. We further demonstrate that the elevated Hedgehog signaling in Sox11-deficient zebrafish was caused by a large increase in shha transcription; indeed, suppressing Shha expression rescued the ocular phenotypes of sox11 morphants. Conversely, over-expression of sox11 induced cyclopia, a phenotype consistent with reduced levels of Sonic hedgehog. We screened DNA samples from 79 patients with microphthalmia, anophthalmia, or coloboma (MAC and identified two novel heterozygous SOX11 variants in individuals with coloboma. In contrast to wild type human SOX11 mRNA, mRNA containing either variant failed to rescue the lens and coloboma phenotypes of Sox11-deficient zebrafish, and both exhibited significantly reduced transactivation ability in a luciferase reporter assay. Moreover, decreased gene dosage from a segmental deletion encompassing the SOX11 locus resulted in microphthalmia and related ocular phenotypes. Therefore, our study reveals a novel role for Sox11 in controlling Hedgehog signaling, and suggests that SOX11 variants contribute to pediatric eye disorders.

Intestinal Hedgehog signaling in tumors and inflammation

NARCIS (Netherlands)

Büller, N.V.J.A.

2015-01-01

In this thesis we investigated the role of Hedgehog signaling in tumors and inflammation. By using an inducible Indian Hedgehog (Ihh) knockout mouse we show that Ihh signals via the mesenchyme to the proliferating cells in the crypt to attenuate proliferation. Despite its anti-proliferative role in

The role of nutraceuticals in the regulation of Wnt and Hedgehog signaling in cancer

Science.gov (United States)

Li, Yiwei; Wang, Zhiwei; Kong, Dejuan

2010-01-01

Multiple cellular signaling pathways have been involved in the processes of cancer cell invasion and metastasis. Among many signaling pathways, Wnt and Hedgehog (Hh) signaling pathways are critically involved in embryonic development, in the biology of cancer stem cells (CSCs) and in the acquisition of epithelial to mesenchymal transition (EMT), and thus this article will remain focused on Wnt and Hh signaling. Since CSCs and EMT are also known to be responsible for cancer cell invasion and metastasis, the Wnt and Hedgehog signaling pathways are also intimately associated with cancer invasion and metastasis. Emerging evidence suggests the beneficial role of chemopreventive agents commonly known as nutraceutical in cancer. Among many such agents, soy isoflavones, curcumin, green tea polyphenols, 3,3′-diindolylmethane, resveratrol, lycopene, vitamin D, etc. have been found to prevent, reverse, or delay the carcinogenic process. Interestingly, these agents have also shown to prevent or delay the progression of cancer, which could in part be due to their ability to attack CSCs or EMT-type cells by attenuating the Wnt and Hedgehog signaling pathways. In this review, we summarize the current state of our knowledge on the role of Wnt and Hedgehog signaling pathways, and their targeted inactivation by chemopreventive agents (nutraceuticals) for the prevention of tumor progression and/or treatment of human malignancies. PMID:20711635

Maintenance of Taste Organs Is Strictly Dependent on Epithelial Hedgehog/GLI Signaling.

Directory of Open Access Journals (Sweden)

Alexandre N Ermilov

2016-11-01

Full Text Available For homeostasis, lingual taste papilla organs require regulation of epithelial cell survival and renewal, with sustained innervation and stromal interactions. To investigate a role for Hedgehog/GLI signaling in adult taste organs we used a panel of conditional mouse models to manipulate GLI activity within epithelial cells of the fungiform and circumvallate papillae. Hedgehog signaling suppression rapidly led to taste bud loss, papilla disruption, and decreased proliferation in domains of papilla epithelium that contribute to taste cells. Hedgehog responding cells were eliminated from the epithelium but retained in the papilla stromal core. Despite papilla disruption and loss of taste buds that are a major source of Hedgehog ligand, innervation to taste papillae was maintained, and not misdirected, even after prolonged GLI blockade. Further, vimentin-positive fibroblasts remained in the papilla core. However, retained innervation and stromal cells were not sufficient to maintain taste bud cells in the context of compromised epithelial Hedgehog signaling. Importantly taste organ disruption after GLI blockade was reversible in papillae that retained some taste bud cell remnants where reactivation of Hedgehog signaling led to regeneration of papilla epithelium and taste buds. Therefore, taste bud progenitors were either retained during epithelial GLI blockade or readily repopulated during recovery, and were poised to regenerate taste buds once Hedgehog signaling was restored, with innervation and papilla connective tissue elements in place. Our data argue that Hedgehog signaling is essential for adult tongue tissue maintenance and that taste papilla epithelial cells represent the key targets for physiologic Hedgehog-dependent regulation of taste organ homeostasis. Because disruption of GLI transcriptional activity in taste papilla epithelium is sufficient to drive taste organ loss, similar to pharmacologic Hedgehog pathway inhibition, the findings

Maintenance of Taste Organs Is Strictly Dependent on Epithelial Hedgehog/GLI Signaling.

Science.gov (United States)

Ermilov, Alexandre N; Kumari, Archana; Li, Libo; Joiner, Ariell M; Grachtchouk, Marina A; Allen, Benjamin L; Dlugosz, Andrzej A; Mistretta, Charlotte M

2016-11-01

For homeostasis, lingual taste papilla organs require regulation of epithelial cell survival and renewal, with sustained innervation and stromal interactions. To investigate a role for Hedgehog/GLI signaling in adult taste organs we used a panel of conditional mouse models to manipulate GLI activity within epithelial cells of the fungiform and circumvallate papillae. Hedgehog signaling suppression rapidly led to taste bud loss, papilla disruption, and decreased proliferation in domains of papilla epithelium that contribute to taste cells. Hedgehog responding cells were eliminated from the epithelium but retained in the papilla stromal core. Despite papilla disruption and loss of taste buds that are a major source of Hedgehog ligand, innervation to taste papillae was maintained, and not misdirected, even after prolonged GLI blockade. Further, vimentin-positive fibroblasts remained in the papilla core. However, retained innervation and stromal cells were not sufficient to maintain taste bud cells in the context of compromised epithelial Hedgehog signaling. Importantly taste organ disruption after GLI blockade was reversible in papillae that retained some taste bud cell remnants where reactivation of Hedgehog signaling led to regeneration of papilla epithelium and taste buds. Therefore, taste bud progenitors were either retained during epithelial GLI blockade or readily repopulated during recovery, and were poised to regenerate taste buds once Hedgehog signaling was restored, with innervation and papilla connective tissue elements in place. Our data argue that Hedgehog signaling is essential for adult tongue tissue maintenance and that taste papilla epithelial cells represent the key targets for physiologic Hedgehog-dependent regulation of taste organ homeostasis. Because disruption of GLI transcriptional activity in taste papilla epithelium is sufficient to drive taste organ loss, similar to pharmacologic Hedgehog pathway inhibition, the findings suggest that taste

Lithium inhibits tumorigenic potential of PDA cells through targeting hedgehog-GLI signaling pathway.

Directory of Open Access Journals (Sweden)

Zhonglu Peng

Full Text Available Hedgehog signaling pathway plays a critical role in the initiation and development of pancreatic ductal adenocarcinoma (PDA and represents an attractive target for PDA treatment. Lithium, a clinical mood stabilizer for mental disorders, potently inhibits the activity of glycogen synthase kinase 3β (GSK3β that promotes the ubiquitin-dependent proteasome degradation of GLI1, an important downstream component of hedgehog signaling. Herein, we report that lithium inhibits cell proliferation, blocks G1/S cell-cycle progression, induces cell apoptosis and suppresses tumorigenic potential of PDA cells through down-regulation of the expression and activity of GLI1. Moreover, lithium synergistically enhances the anti-cancer effect of gemcitabine. These findings further our knowledge of mechanisms of action for lithium and provide a potentially new therapeutic strategy for PDA through targeting GLI1.

WHEN AND WHY DO HEDGEHOGS AND FOXES DIFFER?

Science.gov (United States)

Keil, Frank C

2010-01-01

Philip E. Tetlock's finding that "hedgehog" experts (those with one big theory) are worse predictors than "foxes" (those with multiple, less comprehensive theories) offers fertile ground for future research. Are experts as likely to exhibit hedgehog- or fox-like tendencies in areas that call for explanatory, diagnostic, and skill-based expertise-as they did when Tetlock called on experts to make predictions? Do particular domains of expertise curtail or encourage different styles of expertise? Can we trace these different styles to childhood? Finally, can we nudge hedgehogs to be more like foxes? Current research can only grope at the answers to these questions, but they are essential to gauging the health of expert political judgment.

Cytoarchitectonic and quantitative Golgi study of the hedgehog supraoptic nucleus.

OpenAIRE

Caminero, A A; Machín, C; Sanchez-Toscano, F

1992-01-01

A cytoarchitectural study was made of the supraoptic nucleus (SON) of the hedgehog with special attention to the quantitative comparison of its main neuronal types. The main purposes were (1) to relate the characteristics of this nucleus in the hedgehog (a primitive mammalian insectivorous brain) with those in the SONs of more evolutionarily advanced species; (2) to identify quantitatively the dendritic fields of the main neuronal types in the hedgehog SON and to study their synaptic connecti...

Crystallization and preliminary X-ray analysis of the bacillaene synthase trans-acting acyltransferase PksC

International Nuclear Information System (INIS)

Cuskin, Fiona; Solovyova, Alexandra S.; Lewis, Richard J.; Race, Paul R.

2011-01-01

The expression, purification and crystallization of the trans-acting acyltransferase PksC from the bacillaene hybrid polyketide synthase/nonribosomal peptide synthetase is described. The crystals belonged to the orthorhombic space group P2 1 2 1 2 1 and diffracted to 1.44 Å resolution. The antibiotic bacillaene is biosynthesized in Bacillus subtilis by a hybrid type 1 modular polyketide synthase/nonribosomal peptide synthetase of the trans-acyltransferase (trans-AT) class. Within this system, the essential acyl-group loading activity is provided by the action of three free-standing trans-acting acyltransferases. Here, the recombinant expression, purification and crystallization of the bacillaene synthase trans-acting acyltransferase PksC are reported. A diffraction data set has been collected from a single PksC crystal to 1.44 Å resolution and the crystal was found to belong to the orthorhombic space group P2 1 2 1 2 1

Recruiting a new substrate for triacylglycerol synthesis in plants: the monoacylglycerol acyltransferase pathway.

Directory of Open Access Journals (Sweden)

James R Petrie

Full Text Available BACKGROUND: Monoacylglycerol acyltransferases (MGATs are predominantly associated with lipid absorption and resynthesis in the animal intestine where they catalyse the first step in the monoacylglycerol (MAG pathway by acylating MAG to form diacylglycerol (DAG. Typical plant triacylglycerol (TAG biosynthesis routes such as the Kennedy pathway do not include an MGAT step. Rather, DAG and TAG are synthesised de novo from glycerol-3-phosphate (G-3-P by a series of three subsequent acylation reactions although a complex interplay with membrane lipids exists. METHODOLOGY/PRINCIPAL FINDINGS: We demonstrate that heterologous expression of a mouse MGAT acyltransferase in Nicotiana benthamiana significantly increases TAG accumulation in vegetative tissues despite the low levels of endogenous MAG substrate available. In addition, DAG produced by this acyltransferase can serve as a substrate for both native and coexpressed diacylglycerol acyltransferases (DGAT. Finally, we show that the Arabidopsis thaliana GPAT4 acyltransferase can produce MAG in Saccharomyces cerevisiae using oleoyl-CoA as the acyl-donor. CONCLUSIONS/SIGNIFICANCE: This study demonstrates the concept of a new method of increasing oil content in vegetative tissues by using MAG as a substrate for TAG biosynthesis. Based on in vitro yeast assays and expression results in N. benthamiana, we propose that co-expression of a MAG synthesising enzyme such as A. thaliana GPAT4 and a MGAT or bifunctional M/DGAT can result in DAG and TAG synthesis from G-3-P via a route that is independent and complementary to the endogenous Kennedy pathway and other TAG synthesis routes.

The radial-hedgehog solution in Landau–de Gennes' theory for nematic liquid crystals

KAUST Repository

MAJUMDAR, APALA

2011-09-06

We study the radial-hedgehog solution in a three-dimensional spherical droplet, with homeotropic boundary conditions, within the Landau-de Gennes theory for nematic liquid crystals. The radial-hedgehog solution is a candidate for a global Landau-de Gennes minimiser in this model framework and is also a prototype configuration for studying isolated point defects in condensed matter physics. The static properties of the radial-hedgehog solution are governed by a non-linear singular ordinary differential equation. We study the analogies between Ginzburg-Landau vortices and the radial-hedgehog solution and demonstrate a Ginzburg-Landau limit for the Landau-de Gennes theory. We prove that the radial-hedgehog solution is not the global Landau-de Gennes minimiser for droplets of finite radius and sufficiently low temperatures and prove the stability of the radial-hedgehog solution in other parameter regimes. These results contain quantitative information about the effect of geometry and temperature on the properties of the radial-hedgehog solution and the associated biaxial instabilities. © Copyright Cambridge University Press 2011.

The radial-hedgehog solution in Landau–de Gennes' theory for nematic liquid crystals

KAUST Repository

MAJUMDAR, APALA

2011-01-01

We study the radial-hedgehog solution in a three-dimensional spherical droplet, with homeotropic boundary conditions, within the Landau-de Gennes theory for nematic liquid crystals. The radial-hedgehog solution is a candidate for a global Landau-de Gennes minimiser in this model framework and is also a prototype configuration for studying isolated point defects in condensed matter physics. The static properties of the radial-hedgehog solution are governed by a non-linear singular ordinary differential equation. We study the analogies between Ginzburg-Landau vortices and the radial-hedgehog solution and demonstrate a Ginzburg-Landau limit for the Landau-de Gennes theory. We prove that the radial-hedgehog solution is not the global Landau-de Gennes minimiser for droplets of finite radius and sufficiently low temperatures and prove the stability of the radial-hedgehog solution in other parameter regimes. These results contain quantitative information about the effect of geometry and temperature on the properties of the radial-hedgehog solution and the associated biaxial instabilities. © Copyright Cambridge University Press 2011.

Functional roles of three cutin biosynthetic acyltransferases in cytokinin responses and skotomorphogenesis.

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Lei Wu

Full Text Available Cytokinins (CKs regulate plant development and growth via a two-component signaling pathway. By forward genetic screening, we isolated an Arabidopsis mutant named grow fast on cytokinins 1 (gfc1, whose seedlings grew larger aerial parts on MS medium with CK. gfc1 is allelic to a previously reported cutin mutant defective in cuticular ridges (dcr. GFC1/DCR encodes a soluble BAHD acyltransferase (a name based on the first four enzymes characterized in this family: Benzylalcohol O-acetyltransferase, Anthocyanin O-hydroxycinnamoyltransferase, anthranilate N-hydroxycinnamoyl/benzoyltransferase and Deacetylvindoline 4-O-acetyltransferase with diacylglycerol acyltransferase (DGAT activity in vitro and is necessary for normal cuticle formation on epidermis in vivo. Here we show that gfc1 was a CK-insensitive mutant, as revealed by its low regeneration frequency in vitro and resistance to CK in adventitious root formation and dark-grown hypocotyl inhibition assays. In addition, gfc1 had de-etiolated phenotypes in darkness and was therefore defective in skotomorphogenesis. The background expression levels of most type-A Arabidopsis Response Regulator (ARR genes were higher in the gfc1 mutant. The gfc1-associated phenotypes were also observed in the cutin-deficient glycerol-3-phosphate acyltransferase 4/8 (gpat4/8 double mutant [defective in glycerol-3-phosphate (G3P acyltransferase enzymes GPAT4 and GPAT8, which redundantly catalyze the acylation of G3P by hydroxyl fatty acid (OH-FA], but not in the cutin-deficient mutant cytochrome p450, family 86, subfamily A, polypeptide 2/aberrant induction of type three 1 (cyp86A2/att1, which affects the biosynthesis of some OH-FAs. Our results indicate that some acyltransferases associated with cutin formation are involved in CK responses and skotomorphogenesis in Arabidopsis.

The you gene encodes an EGF-CUB protein essential for Hedgehog signaling in zebrafish.

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Ian G Woods

2005-03-01

Full Text Available Hedgehog signaling is required for many aspects of development in vertebrates and invertebrates. Misregulation of the Hedgehog pathway causes developmental abnormalities and has been implicated in certain types of cancer. Large-scale genetic screens in zebrafish have identified a group of mutations, termed you-class mutations, that share common defects in somite shape and in most cases disrupt Hedgehog signaling. These mutant embryos exhibit U-shaped somites characteristic of defects in slow muscle development. In addition, Hedgehog pathway mutations disrupt spinal cord patterning. We report the positional cloning of you, one of the original you-class mutations, and show that it is required for Hedgehog signaling in the development of slow muscle and in the specification of ventral fates in the spinal cord. The you gene encodes a novel protein with conserved EGF and CUB domains and a secretory pathway signal sequence. Epistasis experiments support an extracellular role for You upstream of the Hedgehog response mechanism. Analysis of chimeras indicates that you mutant cells can appropriately respond to Hedgehog signaling in a wild-type environment. Additional chimera analysis indicates that wild-type you gene function is not required in axial Hedgehog-producing cells, suggesting that You is essential for transport or stability of Hedgehog signals in the extracellular environment. Our positional cloning and functional studies demonstrate that You is a novel extracellular component of the Hedgehog pathway in vertebrates.

Notochord-derived hedgehog is essential for tail regeneration in Xenopus tadpole.

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Taniguchi, Yuka; Watanabe, Kenji; Mochii, Makoto

2014-06-18

Appendage regeneration in amphibians is regulated by the combinatorial actions of signaling molecules. The requirement of molecules secreted from specific tissues is reflected by the observation that the whole process of regeneration can be inhibited if a certain tissue is removed from the amputated stump. Interestingly, urodeles and anurans show different tissue dependencies during tail regeneration. The spinal cord is essential for tail regeneration in urodele but not in anuran larva, whereas the notochord but not the spinal cord is essential for tail regeneration in anuran tadpoles. Sonic hedgehog is one of the signaling molecules responsible for such phenomenon in axolotl, as hedgehog signaling is essential for overall tail regeneration and sonic hedgehog is exclusively expressed in the spinal cord. In order to know whether hedgehog signaling is involved in the molecular mechanism underlying the inconsistent tissue dependency for tail regeneration between anurans and urodeles, we investigated expression of hedgehog signal-related genes in the regenerating tail of Xenopus tadpole and examined the effect of the hedgehog signal inhibitor, cyclopamine, on the tail regeneration. In Xenopus, sonic hedgehog is expressed exclusively in the notochord but not in the spinal cord of the regenerate. Overall regeneration was severely impaired in cyclopamine-treated tadpoles. Notochord maturation in the regenerate, including cell alignment and vacuolation, and myofiber formation were inhibited. Proliferation of spinal cord cells in the neural ampulla and of mesenchymal cells was also impaired. As in the axolotl, hedgehog signaling is required for multiple steps in tail regeneration in the Xenopus tadpole, although the location of the Shh source is quite different between the two species. This difference in Shh localization is the likely basis for the differing tissue requirement for tail regeneration between urodeles and anurans.

Controlling Lipid Fluxes at Glycerol-3-phosphate Acyltransferase Step in Yeast

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Marr, Nancy; Foglia, Julena; Terebiznik, Mauricio; Athenstaedt, Karin; Zaremberg, Vanina

2012-01-01

The ability to channel excess fatty acids into neutral lipids like triacylglycerol (TAG) is a critical strategy used by cells to maintain lipid homeostasis. Upon activation to acyl-CoA, fatty acids become readily available as substrates for acyltransferases involved in neutral lipid synthesis. Neutral lipids are then packed into organelles derived from the endoplasmic reticulum called lipid particles (LPs). The first acylation step in the de novo pathway for TAG synthesis is catalyzed by glycerol-3-phosphate acyltransferases (GPATs). Two isoforms, Gat1p/Gpt2p and Gat2p/Sct1p, are present in the yeast Saccharomyces cerevisiae. Previous evidence indicated that these enzymes contribute differentially to the synthesis of TAG in actively growing cells. In this work we studied the role of the yeast GPATs in the formation of LPs induced by a surplus of oleic acid. Yeast lacking Gat1p (but not Gat2p) were sensitive to oleate and failed to accumulate LPs induced by this unsaturated fatty acid. It is shown that oleate induces dephosphorylation of Gat1p as well as an increment in its levels. Most importantly, we identified novel Gat1p crescent structures that are formed in the presence of oleate. These structures are connected with the endoplasmic reticulum and are intimately associated with LPs. No such structures were observed for Gat2p. A crucial point of control of lipid fluxes at the GPAT step is proposed. PMID:22267742

Hedgehog Pathway Inhibition Radiosensitizes Non-Small Cell Lung Cancers

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Zeng, Jing; Aziz, Khaled; Chettiar, Sivarajan T. [Department of Radiation Oncology and Molecular Radiation Sciences, The Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); Aftab, Blake T. [Department of Medical Oncology, The Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); Armour, Michael; Gajula, Rajendra; Gandhi, Nishant; Salih, Tarek; Herman, Joseph M.; Wong, John [Department of Radiation Oncology and Molecular Radiation Sciences, The Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); Rudin, Charles M. [Department of Medical Oncology, The Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); Tran, Phuoc T. [Department of Radiation Oncology and Molecular Radiation Sciences, The Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); Department of Medical Oncology, The Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); Hales, Russell K., E-mail: rhales1@jhmi.edu [Department of Radiation Oncology and Molecular Radiation Sciences, The Johns Hopkins University School of Medicine, Baltimore, Maryland (United States)

2013-05-01

Purpose: Despite improvements in chemoradiation, local control remains a major clinical problem in locally advanced non-small cell lung cancer. The Hedgehog pathway has been implicated in tumor recurrence by promoting survival of tumorigenic precursors and through effects on tumor-associated stroma. Whether Hedgehog inhibition can affect radiation efficacy in vivo has not been reported. Methods and Materials: We evaluated the effects of a targeted Hedgehog inhibitor (HhAntag) and radiation on clonogenic survival of human non-small cell lung cancer lines in vitro. Using an A549 cell line xenograft model, we examined tumor growth, proliferation, apoptosis, and gene expression changes after concomitant HhAntag and radiation. In a transgenic mouse model of Kras{sup G12D}-induced and Twist1-induced lung adenocarcinoma, we assessed tumor response to radiation and HhAntag by serial micro-computed tomography (CT) scanning. Results: In 4 human lung cancer lines in vitro, HhAntag showed little or no effect on radiosensitivity. By contrast, in both the human tumor xenograft and murine inducible transgenic models, HhAntag enhanced radiation efficacy and delayed tumor growth. By use of the human xenograft model to differentiate tumor and stromal effects, mouse stromal cells, but not human tumor cells, showed significant and consistent downregulation of Hedgehog pathway gene expression. This was associated with increased tumor cell apoptosis. Conclusions: Targeted Hedgehog pathway inhibition can increase in vivo radiation efficacy in lung cancer preclinical models. This effect is associated with pathway suppression in tumor-associated stroma. These data support clinical testing of Hedgehog inhibitors as a component of multimodality therapy for locally advanced non-small cell lung cancer.

Nucleotide sequence of a cDNA for branched chain acyltransferase with analysis of the deduced protein structure

International Nuclear Information System (INIS)

Hummel, K.B.; Litwer, S.; Bradford, A.P.; Aitken, A.; Danner, D.J.; Yeaman, S.J.

1988-01-01

Nucleotide sequence was determined for a 1.6-kilobase human cDNA putative for the branched chain acyltransferase protein of the branched chain α-ketoacid dehydrogenase complex. Translation of the sequence reveals an open reading frame encoding a 315-amino acid protein of molecular weight 35,759 followed by 560 bases of 3'-untranslated sequence. Three repeats of the polyadenylation signal hexamer ATTAAA are present prior to the polyadenylate tail. Within the open reading frame is a 10-amino acid fragment which matches exactly the amino acid sequence around the lipoate-lysine residue in bovine kidney branched chain acyltransferase, thus confirming the identity of the cDNA. Analysis of the deduced protein structure for the human branched chain acyltransferase revealed an organization into domains similar to that reported for the acyltransferase proteins of the pyruvate and α-ketoglutarate dehydrogenase complexes. This similarity in organization suggests that a more detailed analysis of the proteins will be required to explain the individual substrate and multienzyme complex specificity shown by these acyltransferases

Loss of Pin1 Suppresses Hedgehog-Driven Medulloblastoma Tumorigenesis

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Tao Xu

2017-03-01

Full Text Available Medulloblastoma is the most common malignant brain tumor in children. Therapeutic approaches to medulloblastoma (combination of surgery, radiotherapy, and chemotherapy have led to significant improvements, but these are achieved at a high cost to quality of life. Alternative therapeutic approaches are needed. Genetic mutations leading to the activation of the Hedgehog pathway drive tumorigenesis in ~30% of medulloblastoma. In a yeast two-hybrid proteomic screen, we discovered a novel interaction between GLI1, a key transcription factor for the mediation of Hedgehog signals, and PIN1, a peptidylprolyl cis/trans isomerase that regulates the postphosphorylation fate of its targets. The GLI1/PIN1 interaction was validated by reciprocal pulldowns using epitope-tagged proteins in HEK293T cells as well as by co-immunoprecipiations of the endogenous proteins in a medulloblastoma cell line. Our results support a molecular model in which PIN1 promotes GLI1 protein abundance, thus contributing to the positive regulation of Hedgehog signals. Most importantly, in vivo functional analyses of Pin1 in the GFAP-tTA;TRE-SmoA1 mouse model of Hedgehog-driven medulloblastoma demonstrate that the loss of Pin1 impairs tumor development and dramatically increases survival. In summary, the discovery of the GLI1/PIN1 interaction uncovers PIN1 as a novel therapeutic target in Hedgehog-driven medulloblastoma tumorigenesis.

The hedgehog system in ovarian follicles of cattle selected for twin ovulations and births: evidence of a link between the IGF and hedgehog systems

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Hedgehog signaling is involved in regulation of ovarian function in Drosophila but its role in regulating mammalian ovarian folliculogenesis is less clear. Therefore, gene expression of Indian hedgehog (IHH) and its type 1 receptor, patched 1 (PTCH1), were quantified in bovine granulosa (GC) or the...

Hedgehog signaling in development and homeostasis of the gastrointestinal tract

NARCIS (Netherlands)

van den Brink, Gijs R.

2007-01-01

The Hedgehog family of secreted morphogenetic proteins acts through a complex evolutionary conserved signaling pathway to regulate patterning events during development and in the adult organism. In this review I discuss the role of Hedgehog signaling in the development, postnatal maintenance, and

Clinical Implications of Hedgehog Pathway Signaling in Prostate Cancer

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Daniel L. Suzman

2015-09-01

Full Text Available Activity in the Hedgehog pathway, which regulates GLI-mediated transcription, is important in organogenesis and stem cell regulation in self-renewing organs, but is pathologically elevated in many human malignancies. Mutations leading to constitutive activation of the pathway have been implicated in medulloblastoma and basal cell carcinoma, and inhibition of the pathway has demonstrated clinical responses leading to the approval of the Smoothened inhibitor, vismodegib, for the treatment of advanced basal cell carcinoma. Aberrant Hedgehog pathway signaling has also been noted in prostate cancer with evidence suggesting that it may render prostate epithelial cells tumorigenic, drive the epithelial-to-mesenchymal transition, and contribute towards the development of castration-resistance through autocrine and paracrine signaling within the tumor microenvironment and cross-talk with the androgen pathway. In addition, there are emerging clinical data suggesting that inhibition of the Hedgehog pathway may be effective in the treatment of recurrent and metastatic prostate cancer. Here we will review these data and highlight areas of active clinical research as they relate to Hedgehog pathway inhibition in prostate cancer.

The imidazopyridine derivative JK184 reveals dual roles for microtubules in Hedgehog signaling.

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Cupido, Tommaso; Rack, Paul G; Firestone, Ari J; Hyman, Joel M; Han, Kyuho; Sinha, Surajit; Ocasio, Cory A; Chen, James K

2009-01-01

Eradicating hedgehogs: The title molecule has been previously identified as a potent inhibitor of the Hedgehog signaling pathway, which gives embryonic cells information needed to develop properly. This molecule is shown to modulate Hedgehog target gene expression by depolymerizing microtubules, thus revealing dual roles of the cytoskeleton in pathway regulation (see figure).

Sonic hedgehog promotes somitic chondrogenesis by altering the cellular response to BMP signaling

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Murtaugh, L. Charles; Chyung, Jay H.; Lassar, Andrew B.

1999-01-01

Previous work has indicated that signals from the floor plate and notochord promote chondrogenesis of the somitic mesoderm. These tissues, acting through the secreted signaling molecule Sonic hedgehog (Shh), appear to be critical for the formation of the sclerotome. Later steps in the differentiation of sclerotome into cartilage may be independent of the influence of these axial tissues. Although the signals involved in these later steps have not yet been pinpointed, there is substantial evid...

Static flexural properties of hedgehog spines conditioned in coupled temperature and relative humidity environments.

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Kennedy, Emily B; Hsiung, Bor-Kai; Swift, Nathan B; Tan, Kwek-Tze

2017-11-01

Hedgehogs are agile climbers, scaling trees and plants to heights exceeding 10m while foraging insects. Hedgehog spines (a.k.a. quills) provide fall protection by absorbing shock and could offer insights for the design of lightweight, material-efficient, impact-resistant structures. There has been some study of flexural properties of hedgehog spines, but an understanding of how this keratinous biological material is affected by various temperature and relative humidity treatments, or how spine color (multicolored vs. white) affects mechanics, is lacking. To bridge this gap in the literature, we use three-point bending to analyze the effect of temperature, humidity, spine color, and their interactions on flexural strength and modulus of hedgehog spines. We also compare specific strength and stiffness of hedgehog spines to conventional engineered materials. We find hedgehog spine flexural properties can be finely tuned by modifying environmental conditioning parameters. White spines tend to be stronger and stiffer than multicolored spines. Finally, for most temperature and humidity conditioning parameters, hedgehog spines are ounce for ounce stronger than 201 stainless steel rods of the same diameter but as pliable as styrene rods with a slightly larger diameter. This unique combination of strength and elasticity makes hedgehog spines exemplary shock absorbers, and a suitable reference model for biomimicry. Copyright © 2017 Elsevier Ltd. All rights reserved.

Novel Hedgehog pathway targets against basal cell carcinoma

International Nuclear Information System (INIS)

Tang, Jean Y.; So, P.-L.; Epstein, Ervin H.

2007-01-01

The Hedgehog signaling pathway plays a key role in directing growth and patterning during embryonic development and is required in vertebrates for the normal development of many structures, including the neural tube, axial skeleton, skin, and hair. Aberrant activation of the Hedgehog (Hh) pathway in adult tissue is associated with the development of basal cell carcinoma (BCC), medulloblastoma, and a subset of pancreatic, gastrointestinal, and other cancers. This review will provide an overview of what is known about the mechanisms by which activation of Hedgehog signaling leads to the development of BCCs and will review two recent papers suggesting that agents that modulate sterol levels might influence the Hh pathway. Thus, sterols may be a new therapeutic target for the treatment of BCCs, and readily available agents such as statins (HMG-CoA reductase inhibitors) or vitamin D might be helpful in reducing BCC incidence

Loss of Sonic hedgehog leads to alterations in intestinal secretory cell maturation and autophagy.

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Jessica Gagné-Sansfaçon

Full Text Available BACKGROUND: Intestinal epithelial cells express the Sonic and Indian hedgehog ligands. Despite the strong interest in gut hedgehog signaling in GI diseases, no studies have specifically addressed the singular role of intestinal epithelial cell Sonic hedgehog signaling. The aim of this study was to investigate the specific role of Sonic hedgehog in adult ileal epithelial homeostasis. METHODOLOGY/PRINCIPAL FINDINGS: A Sonic hedgehog intestinal epithelial conditional knockout mouse model was generated. Assessment of ileal histological abnormalities, crypt epithelial cell proliferation, epithelial cell fate, junctional proteins, signaling pathways, as well as ultrastructural analysis of intracellular organelles were performed in control and mutant mice. Mice lacking intestinal epithelial Sonic Hedgehog displayed decreased ileal crypt/villus length, decreased crypt proliferation as well as a decrease in the number of ileal mucin-secreting goblet cells and antimicrobial peptide-secreting Paneth cells during adult life. These secretory cells also exhibited disruption of their secretory products in mutant mice. Ultrastructural microscopy analysis revealed a dilated ER lumen in secretory cells. This phenotype was also associated with a decrease in autophagy. CONCLUSIONS/SIGNIFICANCE: Altogether, these findings indicate that the loss of Sonic hedgehog can lead to ileal secretory cell modifications indicative of endoplasmic reticulum stress, accompanied by a significant reduction in autophagy.

Molecular Characterization of Two Lysophospholipid:acyl-CoA Acyltransferases Belonging to the MBOAT Family in Nicotiana benthamiana.

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Donghui Zhang

Full Text Available In the remodeling pathway for the synthesis of phosphatidylcholine (PC, acyl-CoA-dependent lysophosphatidylcholine (lysoPC acyltransferase (LPCAT catalyzes the reacylation of lysoPC. A number of genes encoding LPCATs have been cloned and characterized from several plants in recent years. Using Arabidopsis and other plant LPCAT sequences to screen the genome database of Nicotiana benthamiana, we identified two cDNAs encoding the putative tobacco LPCATs (NbLPCAT1 and NbLPCAT2. Both of them were predicted to encode a protein of 463 amino acids with high similarity to LPCATs from other plants. Protein sequence features such as the presence of at least eight putative transmembrane regions, four highly conserved signature motifs and several invariant residues indicate that NbLPCATs belong to the membrane bound O-acyltransferase family. Lysophospholipid acyltransferase activity of NbLPCATs was confirmed by testing lyso-platelet-activating factor (lysoPAF sensitivity through heterologous expression of each full-length cDNA in a yeast mutant Y02431 (lca1△ disrupted in endogenous LPCAT enzyme activity. Analysis of fatty acid profiles of phospholipids from the NbLPCAT-expressing yeast mutant Y02431 cultures supplemented with polyunsaturated fatty acids suggested more incorporation of linoleic acid (18:2n6, LA and α-linolenic acid (18:3n3, ALA into PC compared to yeast mutant harbouring empty vector. In vitro enzymatic assay demonstrated that NbLPCAT1had high lysoPC acyltransferase activity with a clear preference for α-linolenoyl-CoA (18:3, while NbLPCAT2 showed a high lysophosphatidic acid (lysoPA acyltransferase activity towards α-linolenoyl-CoA and a weak lysoPC acyltransferase activity. Tissue-specific expression analysis showed a ubiquitous expression of NbLPCAT1 and NbLPCAT2 in roots, stems, leaves, flowers and seeds, and a strong expression in developing flowers. This is the first report on the cloning and characterization of lysophospholipid

The Role of Lecithin: Retinol Acyltransferase (LRAT)-Mediated Esterification of Vitamin A in Regulating Human Breast Cancer Cell Proliferation and Differentiation

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2007-04-01

involved in thetranscriptional regulation of the human LRAT gene. 15. SUBJECT TERMS Breast cancer, lecithin : Retinol Acyltransferase (LRAT...R.R., Nanus, D.M., Scherr, D.S., and Gudas, L.J. 2004. Reduced lecithin : retinol acyltransferase expression correlates with increased pathologic...Solubilization and partial characterization of lecithin -retinol acyltransferase from rat liver. J Nutr Biochem 2: 503-511. Isogai, M., Chiantore, M.V., Haque

Radiological investigations of the hedgehog (Erinaceus concolor) appendicular skeleton.

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Hashemi, Mohammad; Javadi, Shahram; Hadian, Mojtaba; Pourreza, Behzad; Behfar, Mahdi

2009-03-01

The normal radiographic anatomy of the healthy hedgehog can help to identify anatomic features unique to the hedgehog while comparing it with other small mammals, such as the dog and cat. Radiographic examination is a method that can play an important role in the diagnosis of a wide variety of skeletal diseases. Seven (2 males, 5 females) free-living hedgehogs (Erinaceus concolor) from the Urmia region of Iran were selected for this study. Lateral and craniocaudal radiographs from the front and hind limbs were obtained. The radiographs from these hedgehogs were compared with the normal canine and feline skeletal radiographic anatomy. On the forelimb radiographs, the clavicle was observed as a complete bone connected to the scapula and manubrium. There are three and five carpal bones in the proximal and distal rows, respectively, as in the dog and cat. The pelvis has a larger obturator foramen when compared with the dog and cat. In the lateral view, the pubis and ischium are relatively larger than in the dog and cat and have a more ventral position. The tarsal bones are similar to those of the dog and cat. The number of phalanges and sesamoid bones in the forelimb and hindlimb are likewise similar to those found in the dog and cat.

Sonic Hedgehog Signaling Promotes Tumor Growth

National Research Council Canada - National Science Library

Bushman, Wade

2007-01-01

... of the DOD New Investigator award indicate that Shh signaling promotes tumor growth. This proposal addresses the hypothesis that Sonic hedgehog signaling promotes tumor growth by activating stromal cell gene expression...

Effects of a natural fire on a Kuenzler's hedgehog cactus (Echinocereus fendleri var. kuenzleri) and nylon hedgehog cactus (Echinocereus viridiflorus) population in Southeastern New Mexico

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Robert C. Sivinski

2007-01-01

During the summer of 1992, a natural wildfire burned 250 acres of juniper savanna on Rawhide Ridge in the Guadalupe Mountains of southeastern New Mexico. This fire burned through the center of a Kuenzler's hedgehog cactus population. This threatened cactus is locally sympatric with the more abundant nylon hedgehog cactus, which has similar growth form and stature...

Hedgehog pathway does not play a role in hidradenitis suppurativa pathogenesis

DEFF Research Database (Denmark)

Mozeika, E.; Jemec, G.B.E.; Nürnberg, B.M.

2011-01-01

in normal embryonic skin, hair follicle, sebaceous and sweat gland development. Mutations of hedgehog pathway in adult skin have previously been found in basal cell carcinomas and in alopecia as well as in epidermal cysts and in odontogenic keratocysts. Therefore, we suggested that the hedgehog pathway...

Live imaging of individual cell divisions in mouse neuroepithelium shows asymmetry in cilium formation and Sonic hedgehog response

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Piotrowska-Nitsche Karolina

2012-05-01

Full Text Available Abstract Background Primary cilia are microtubule-based sensory organelles that play important roles in developmental signaling pathways. Recent work demonstrated that, in cell culture, the daughter cell that inherits the older mother centriole generates a primary cilium and responds to external stimuli prior to its sister cell. This asynchrony in timing of cilia formation could be especially critical during development as cell divisions are required for both differentiation and maintenance of progenitor cell niches. Methods Here we integrate several fluorescent markers and use ex vivo live imaging of a single cell division within the mouse E8.5 neuroepithelium to reveal both the formation of a primary cilium and the transcriptional response to Sonic hedgehog in the daughter cells. Results We show that, upon cell division, cilia formation and the Sonic hedgehog response are asynchronous between the daughter cells. Conclusions Our results demonstrate that we can directly observe single cell divisions within the developing neuroepithelium and concomitantly monitor cilium formation or Sonic hedgehog response. We expect this method to be especially powerful in examining whether cellular behavior can lead to both differentiation and maintenance of cells in a progenitor niche.

Functional Interaction between HEXIM and Hedgehog Signaling during Drosophila Wing Development.

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Nguyen, Duy; Fayol, Olivier; Buisine, Nicolas; Lecorre, Pierrette; Uguen, Patricia

2016-01-01

Studying the dynamic of gene regulatory networks is essential in order to understand the specific signals and factors that govern cell proliferation and differentiation during development. This also has direct implication in human health and cancer biology. The general transcriptional elongation regulator P-TEFb regulates the transcriptional status of many developmental genes. Its biological activity is controlled by an inhibitory complex composed of HEXIM and the 7SK snRNA. Here, we examine the function of HEXIM during Drosophila development. Our key finding is that HEXIM affects the Hedgehog signaling pathway. HEXIM knockdown flies display strong phenotypes and organ failures. In the wing imaginal disc, HEXIM knockdown initially induces ectopic expression of Hedgehog (Hh) and its transcriptional effector Cubitus interuptus (Ci). In turn, deregulated Hedgehog signaling provokes apoptosis, which is continuously compensated by apoptosis-induced cell proliferation. Thus, the HEXIM knockdown mutant phenotype does not result from the apoptotic ablation of imaginal disc; but rather from the failure of dividing cells to commit to a proper developmental program due to Hedgehog signaling defects. Furthermore, we show that ci is a genetic suppressor of hexim. Thus, HEXIM ensures the integrity of Hedgehog signaling in wing imaginal disc, by a yet unknown mechanism. To our knowledge, this is the first time that the physiological function of HEXIM has been addressed in such details in vivo.

Functional Interaction between HEXIM and Hedgehog Signaling during Drosophila Wing Development.

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Duy Nguyen

Full Text Available Studying the dynamic of gene regulatory networks is essential in order to understand the specific signals and factors that govern cell proliferation and differentiation during development. This also has direct implication in human health and cancer biology. The general transcriptional elongation regulator P-TEFb regulates the transcriptional status of many developmental genes. Its biological activity is controlled by an inhibitory complex composed of HEXIM and the 7SK snRNA. Here, we examine the function of HEXIM during Drosophila development. Our key finding is that HEXIM affects the Hedgehog signaling pathway. HEXIM knockdown flies display strong phenotypes and organ failures. In the wing imaginal disc, HEXIM knockdown initially induces ectopic expression of Hedgehog (Hh and its transcriptional effector Cubitus interuptus (Ci. In turn, deregulated Hedgehog signaling provokes apoptosis, which is continuously compensated by apoptosis-induced cell proliferation. Thus, the HEXIM knockdown mutant phenotype does not result from the apoptotic ablation of imaginal disc; but rather from the failure of dividing cells to commit to a proper developmental program due to Hedgehog signaling defects. Furthermore, we show that ci is a genetic suppressor of hexim. Thus, HEXIM ensures the integrity of Hedgehog signaling in wing imaginal disc, by a yet unknown mechanism. To our knowledge, this is the first time that the physiological function of HEXIM has been addressed in such details in vivo.

Metabolites in vertebrate Hedgehog signaling.

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Roberg-Larsen, Hanne; Strand, Martin Frank; Krauss, Stefan; Wilson, Steven Ray

2014-04-11

The Hedgehog (HH) signaling pathway is critical in embryonic development, stem cell biology, tissue homeostasis, chemoattraction and synapse formation. Irregular HH signaling is associated with a number of disease conditions including congenital disorders and cancer. In particular, deregulation of HH signaling has been linked to skin, brain, lung, colon and pancreatic cancers. Key mediators of the HH signaling pathway are the 12-pass membrane protein Patched (PTC), the 7-pass membrane protein Smoothened (SMO) and the GLI transcription factors. PTC shares homology with the RND family of small-molecule transporters and it has been proposed that it interferes with SMO through metabolites. Although a conclusive picture is lacking, substantial efforts are made to identify and understand natural metabolites/sterols, including cholesterol, vitamin D3, oxysterols and glucocorticoides, that may be affected by, or influence the HH signaling cascade at the level of PTC and SMO. In this review we will elaborate the role of metabolites in HH signaling with a focus on oxysterols, and discuss advancements in modern analytical approaches in the field. Copyright © 2014 Elsevier Inc. All rights reserved.

[Hedgehog fungi in a dermatological office in Munich : Case reports and review].

Science.gov (United States)

Kargl, A; Kosse, B; Uhrlaß, S; Koch, D; Krüger, C; Eckert, K; Nenoff, P

2018-02-12

Patient 1: After contact to a central European hedgehog (Erinaceus europaeus), a 50-year-old female with atopy developed erythrosquamous tinea manus on the thumb and thenar eminence of the right hand. The patient had previously been scalded by hot steam at the affected site. The zoophilic dermatophyte Trichophyton erinacei could be cultured from the hedgehog as well as from scrapings from the woman's skin. Antifungal treatment of the hedgehog was initiated using 2 weekly cycles of itraconazole solution (0.1 ml/kg body weight, BW). In addition, every other day enilconazole solution was used for topical treatment. The patient was treated with ciclopirox olamine cream and oral terbinafine 250 mg daily for 2 weeks, which led to healing of the Tinea manus .Patient 2: An 18-year-old woman presented for emergency consultation with rimmed, papulous, vesicular and erosive crusted skin lesions of the index finger, and an erythematous dry scaling round lesion on the thigh. The patient worked at an animal care facility, specifically caring for hedgehogs. One of the hedgehogs suffered from a substantial loss of spines. Fungal cultures from skin scrapings of both lesions yielded T. erinacei. Treatment with ciclopirox olamine cream and oral terbinafine 250 mg for 14 days was initiated which led to healing of the lesions. Identification of all three T. erinacei isolates from both patients and from the hedgehog was confirmed by sequencing of the internal transcribed spacer (ITS) region of the ribosomal DNA, and of the translation elongation factor (TEF)-1-alpha gene. Using ITS sequencing discrimination between T. erinacei strains from European and from African hedgehogs is possible. T. erinacei should be considered a so-called emerging pathogen. In Germany the zoophilic dermatophyte T. erinacei should be taken into account as causative agent of dermatomycoses in humans after contact to hedgehogs.

Canonical hedgehog signaling augments tumor angiogenesis by induction of VEGF-A in stromal perivascular cells

OpenAIRE

Chen, Weiwei; Tang, Tracy; Eastham-Anderson, Jeff; Dunlap, Debra; Alicke, Bruno; Nannini, Michelle; Gould, Stephen; Yauch, Robert; Modrusan, Zora; DuPree, Kelly J.; Darbonne, Walter C.; Plowman, Greg; de Sauvage, Frederic J.; Callahan, Christopher A.

2011-01-01

Hedgehog (Hh) signaling is critical to the patterning and development of a variety of organ systems, and both ligand-dependent and ligand-independent Hh pathway activation are known to promote tumorigenesis. Recent studies have shown that in tumors promoted by Hh ligands, activation occurs within the stromal microenvironment. Testing whether ligand-driven Hh signaling promotes tumor angiogenesis, we found that Hh antagonism reduced the vascular density of Hh-producing LS180 and SW480 xenograf...

Participation of Polycomb group gene extra sex combs in hedgehog signaling pathway

International Nuclear Information System (INIS)

Shindo, Norihisa; Sakai, Atsushi; Yamada, Kouji; Higashinakagawa, Toru

2004-01-01

Polycomb group (PcG) genes are required for stable inheritance of epigenetic states across cell divisions, a phenomenon termed cellular memory. PcG proteins form multimeric nuclear complex which modifies the chromatin structure of target site. Drosophila PcG gene extra sex combs (esc) and its vertebrate orthologs constitute a member of ESC-E(Z) complex, which possesses histone methyltransferase activity. Here we report isolation and characterization of medaka esc homolog, termed oleed. Hypomorphic knock-down of oleed using morpholino antisense oligonucleotides resulted in the fusion of eyes, termed cyclopia. Prechordal plate formation was not substantially impaired, but expression of hedgehog target genes was dependent on oleed, suggesting some link with hedgehog signaling. In support of this implication, histone methylation, which requires the activity of esc gene product, is increased in hedgehog stimulated mouse NIH-3T3 cells. Our data argue for the novel role of esc in hedgehog signaling and provide fundamental insight into the epigenetic mechanisms in general

Phosphatidylserine-stimulated production of N-acyl-phosphatidylethanolamines by Ca2+-dependent N-acyltransferase.

Science.gov (United States)

Hussain, Zahir; Uyama, Toru; Kawai, Katsuhisa; Binte Mustafiz, Smriti Sultana; Tsuboi, Kazuhito; Araki, Nobukazu; Ueda, Natsuo

2018-05-01

N-acyl-phosphatidylethanolamine (NAPE) is known to be a precursor for various bioactive N-acylethanolamines including the endocannabinoid anandamide. NAPE is produced in mammals through the transfer of an acyl chain from certain glycerophospholipids to phosphatidylethanolamine (PE) by Ca 2+ -dependent or -independent N-acyltransferases. The ε isoform of mouse cytosolic phospholipase A 2 (cPLA 2 ε) was recently identified as a Ca 2+ -dependent N-acyltransferase (Ca-NAT). In the present study, we first showed that two isoforms of human cPLA 2 ε function as Ca-NAT. We next purified both mouse recombinant cPLA 2 ε and its two human orthologues to examine their catalytic properties. The enzyme absolutely required Ca 2+ for its activity and the activity was enhanced by phosphatidylserine (PS). PS enhanced the activity 25-fold in the presence of 1 mM CaCl 2 and lowered the EC 50 value of Ca 2+ >8-fold. Using a PS probe, we showed that cPLA 2 ε largely co-localizes with PS in plasma membrane and organelles involved in the endocytic pathway, further supporting the interaction of cPLA 2 ε with PS in living cells. Finally, we found that the Ca 2+ -ionophore ionomycin increased [ 14 C]NAPE levels >10-fold in [ 14 C]ethanolamine-labeled cPLA 2 ε-expressing cells while phospholipase A/acyltransferase-1, acting as a Ca 2+ -independent N-acyltransferase, was insensitive to ionomycin for full activity. In conclusion, PS potently stimulated the Ca 2+ -dependent activity and human cPLA 2 ε isoforms also functioned as Ca-NAT. Copyright © 2018 Elsevier B.V. All rights reserved.

Phospholipase A2-treated human high-density lipoprotein and cholesterol movements: exchange processes and lecithin: cholesterol acyltransferase reactivity.

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Chollet, F; Perret, B P; Chap, H; Douste-Blazy, L

1986-02-12

Human HDL3 (d 1.125-1.21 g/ml) were treated by an exogenous phospholipase A2 from Crotalus adamenteus in the presence of albumin. Phosphatidylcholine hydrolysis ranged between 30 and 90% and the reisolated particle was essentially devoid of lipolysis products. (1) An exchange of free cholesterol was recorded between radiolabelled erythrocytes at 5-10% haematocrit and HDL3 (0.6 mM total cholesterol) from 0 to 12-15 h. Isotopic equilibration was reached. Kinetic analysis of the data indicated a constant rate of free cholesterol exchange of 13.0 microM/h with a half-time of equilibration around 3 h. Very similar values of cholesterol exchange, specific radioactivities and kinetic parameters were measured when phospholipase-treated HDL replaced control HDL. (2) The lecithin: cholesterol acyltransferase reactivity of HDL3, containing different amounts of phosphatidylcholine, as achieved by various degrees of phospholipase A2 treatment, was measured using a crude preparation of lecithin: cholesterol acyltransferase (the d 1.21-1.25 g/ml plasma fraction). The rate of esterification was determined between 0 and 12 h. Following a 15-30% lipolysis, the lecithin: cholesterol acyltransferase reactivity of HDL3 was reduced about 30-40%, and then continued to decrease, though more slowly, as the phospholipid content was further lowered in the particle. (3) The addition of the lecithin: cholesterol acyltransferase preparation into an incubation medium made of labelled erythrocytes and HDL3 promoted a movement of radioactive cholesterol out of cells, above the values of exchange, and an accumulation of cholesteryl esters in HDL. This reflected a mass consumption of free cholesterol, from both the cellular and the lipoprotein compartments upon the lecithin: cholesterol acyltransferase action. As a consequence of a decreased reactivity, phospholipase-treated HDL (with 2/3 of phosphatidylcholine hydrolyzed) proved much less effective in the lecithin: cholesterol acyltransferase

Dendrosomatic Sonic Hedgehog Signaling in Hippocampal Neurons Regulates Axon Elongation

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Petralia, Ronald S.; Ott, Carolyn; Wang, Ya-Xian; Lippincott-Schwartz, Jennifer; Mattson, Mark P.

2015-01-01

The presence of Sonic Hedgehog (Shh) and its signaling components in the neurons of the hippocampus raises a question about what role the Shh signaling pathway may play in these neurons. We show here that activation of the Shh signaling pathway stimulates axon elongation in rat hippocampal neurons. This Shh-induced effect depends on the pathway transducer Smoothened (Smo) and the transcription factor Gli1. The axon itself does not respond directly to Shh; instead, the Shh signal transduction originates from the somatodendritic region of the neurons and occurs in neurons with and without detectable primary cilia. Upon Shh stimulation, Smo localization to dendrites increases significantly. Shh pathway activation results in increased levels of profilin1 (Pfn1), an actin-binding protein. Mutations in Pfn1's actin-binding sites or reduction of Pfn1 eliminate the Shh-induced axon elongation. These findings indicate that Shh can regulate axon growth, which may be critical for development of hippocampal neurons. SIGNIFICANCE STATEMENT Although numerous signaling mechanisms have been identified that act directly on axons to regulate their outgrowth, it is not known whether signals transduced in dendrites may also affect axon outgrowth. We describe here a transcellular signaling pathway in embryonic hippocampal neurons in which activation of Sonic Hedgehog (Shh) receptors in dendrites stimulates axon growth. The pathway involves the dendritic-membrane-associated Shh signal transducer Smoothened (Smo) and the transcription factor Gli, which induces the expression of the gene encoding the actin-binding protein profilin 1. Our findings suggest scenarios in which stimulation of Shh in dendrites results in accelerated outgrowth of the axon, which therefore reaches its presumptive postsynaptic target cell more quickly. By this mechanism, Shh may play critical roles in the development of hippocampal neuronal circuits. PMID:26658865

Gli2a protein localization reveals a role for Iguana/DZIP1 in primary ciliogenesis and a dependence of Hedgehog signal transduction on primary cilia in the zebrafish

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van Eeden Freek

2010-04-01

Full Text Available Abstract Background In mammalian cells, the integrity of the primary cilium is critical for proper regulation of the Hedgehog (Hh signal transduction pathway. Whether or not this dependence on the primary cilium is a universal feature of vertebrate Hedgehog signalling has remained contentious due, in part, to the apparent divergence of the intracellular transduction pathway between mammals and teleost fish. Results Here, using a functional Gli2-GFP fusion protein, we show that, as in mammals, the Gli2 transcription factor localizes to the primary cilia of cells in the zebrafish embryo and that this localization is modulated by the activity of the Hh pathway. Moreover, we show that the Igu/DZIP1protein, previously implicated in the modulation of Gli activity in zebrafish, also localizes to the primary cilium and is required for its proper formation. Conclusion Our findings demonstrate a conserved role of the primary cilium in mediating Hedgehog signalling activity across the vertebrate phylum and validate the use of the zebrafish as a representative model for the in vivo analysis of vertebrate Hedgehog signalling.

OSTEOSARCOMA IN AFRICAN HEDGEHOGS (ATELERIX ALBIVENTRIS): FIVE CASES.

Science.gov (United States)

Reyes-Matute, Alonso; Méndez-Bernal, Adriana; Ramos-Garduño, Liliana-Aurora

2017-06-01

Osteosarcomas are unusual neoplasms in African hedgehogs ( Atelerix albiventris ) and have been reported in extraskeletal and skeletal locations, including mandible, ribs, and vertebra. Five hedgehogs with osteosarcoma submitted to the Pathology Department at Facultad de Medicina Veterinaria y Zootecnia, National Autonomous University of Mexico are reported. In two cases, the neoplasm arose from the skull; one case arose from the ribs with associated compression of the thoracic and abdominal cavity, and another case involved the vertebrae. In the last case, the neoplasm arose from the scapula. Histologic lesions were similar in all cases and consisted of well-demarcated nodules in which neoplastic cells were arranged in sheets of polyhedral to spindle-shaped cells with interspersed areas of necrosis. Numerous trabeculae of osteoid were present throughout the tumors. No metastases were detected. The predominant histologic pattern was osteoblastic, but a telangiectatic-like pattern was observed in the vertebral osteosarcoma. Electron microscopy was performed in two cases, and malignant osteoblasts had features consistent with descriptions in other species, including deposits of hydroxyapatite in osteoid. According to these cases and previously published data, axial osteosarcomas are more frequent in contrast to appendicular osteosarcomas in African hedgehogs, and metastases are rare.

Structure of a bacterial toxin-activating acyltransferase.

Science.gov (United States)

Greene, Nicholas P; Crow, Allister; Hughes, Colin; Koronakis, Vassilis

2015-06-09

Secreted pore-forming toxins of pathogenic Gram-negative bacteria such as Escherichia coli hemolysin (HlyA) insert into host-cell membranes to subvert signal transduction and induce apoptosis and cell lysis. Unusually, these toxins are synthesized in an inactive form that requires posttranslational activation in the bacterial cytosol. We have previously shown that the activation mechanism is an acylation event directed by a specialized acyl-transferase that uses acyl carrier protein (ACP) to covalently link fatty acids, via an amide bond, to specific internal lysine residues of the protoxin. We now reveal the 2.15-Å resolution X-ray structure of the 172-aa ApxC, a toxin-activating acyl-transferase (TAAT) from pathogenic Actinobacillus pleuropneumoniae. This determination shows that bacterial TAATs are a structurally homologous family that, despite indiscernible sequence similarity, form a distinct branch of the Gcn5-like N-acetyl transferase (GNAT) superfamily of enzymes that typically use acyl-CoA to modify diverse bacterial, archaeal, and eukaryotic substrates. A combination of structural analysis, small angle X-ray scattering, mutagenesis, and cross-linking defined the solution state of TAATs, with intermonomer interactions mediated by an N-terminal α-helix. Superposition of ApxC with substrate-bound GNATs, and assay of toxin activation and binding of acyl-ACP and protoxin peptide substrates by mutated ApxC variants, indicates the enzyme active site to be a deep surface groove.

Lipid Oxidation in Carriers of Lecithin: Cholesterol Acyltransferase Gene Mutations

NARCIS (Netherlands)

Holleboom, Adriaan G.; Daniil, Georgios; Fu, Xiaoming; Zhang, Renliang; Hovingh, G. Kees; Schimmel, Alinda W.; Kastelein, John J. P.; Stroes, Erik S. G.; Witztum, Joseph L.; Hutten, Barbara A.; Tsimikas, Sotirios; Hazen, Stanley L.; Chroni, Angeliki; Kuivenhoven, Jan Albert

2012-01-01

Objective-Lecithin:cholesterol acyltransferase (LCAT) has been shown to play a role in the depletion of lipid oxidation products, but this has so far not been studied in humans. In this study, we investigated processes and parameters relevant to lipid oxidation in carriers of functional LCAT

Lipid Oxidation in Carriers of Lecithin : Cholesterol Acyltransferase Gene Mutations

NARCIS (Netherlands)

Holleboom, Adriaan G.; Daniil, Georgios; Fu, Xiaoming; Zhang, Renliang; Hovingh, G. Kees; Schimmel, Alinda W.; Kastelein, John J. P.; Stroes, Erik S. G.; Witztum, Joseph L.; Hutten, Barbara A.; Tsimikas, Sotirios; Hazen, Stanley L.; Chroni, Angeliki; Kuivenhoven, Jan Albert

2012-01-01

OBJECTIVE: Lecithin:cholesterol acyltransferase (LCAT) has been shown to play a role in the depletion of lipid oxidation products, but this has so far not been studied in humans. In this study, we investigated processes and parameters relevant to lipid oxidation in carriers of functional LCAT

Characterization of reconstituted partially purified glycerophosphate acyltransferase from Escherichia coli

NARCIS (Netherlands)

Kessels, J.M.M.; Bosch, H. van den

1982-01-01

A modification of the method of Snider and Kennedy (J. Bacteriol. (1977) 130, 1072–1083) was worked out to solubilize sn-glycero-3-phosphate acyltransferase from whole cells by Triton X-100. The solubilized preparation was used for a systematic study of the reconstitution of enzymatic activity as

Cytoarchitectonic and quantitative Golgi study of the hedgehog supraoptic nucleus.

Science.gov (United States)

Caminero, A A; Machín, C; Sanchez-Toscano, F

1992-02-01

A cytoarchitectural study was made of the supraoptic nucleus (SON) of the hedgehog with special attention to the quantitative comparison of its main neuronal types. The main purposes were (1) to relate the characteristics of this nucleus in the hedgehog (a primitive mammalian insectivorous brain) with those in the SONs of more evolutionarily advanced species; (2) to identify quantitatively the dendritic fields of the main neuronal types in the hedgehog SON and to study their synaptic connectivity. From a descriptive standpoint, 3 neuronal types were found with respect to the number of dendritic stems arising from the neuronal soma: bipolar neurons (48%), multipolar neurons (45.5%) and monopolar neurons (6.5%). Within the multipolar type 2 subtypes could be distinguished, taking into account the number of dendritic spines: (a) with few spines (93%) and (b) very spiny (7%). These results indicate that the hedgehog SON is similar to that in other species except for the very spiny neurons, the significance of which is discussed. In order to characterise the main types more satisfactorily (bipolar and multipolars with few spines) we undertook a quantitative Golgi study of their dendritic fields. Although the patterns of the dendritic field are similar in both neuronal types, the differences in the location of their connectivity can reflect functional changes and alterations in relation to the synaptic afferences.

Hedgehog Signaling Components Are Expressed in Choroidal Neovascularization in Laser-induced Retinal Lesion

International Nuclear Information System (INIS)

Nochioka, Katsunori; Okuda, Hiroaki; Tatsumi, Kouko; Morita, Shoko; Ogata, Nahoko; Wanaka, Akio

2016-01-01

Choroidal neovascularization is one of the major pathological changes in age-related macular degeneration, which causes devastating blindness in the elderly population. The molecular mechanism of choroidal neovascularization has been under extensive investigation, but is still an open question. We focused on sonic hedgehog signaling, which is implicated in angiogenesis in various organs. Laser-induced injuries to the mouse retina were made to cause choroidal neovascularization. We examined gene expression of sonic hedgehog, its receptors (patched1, smoothened, cell adhesion molecule down-regulated by oncogenes (Cdon) and biregional Cdon-binding protein (Boc)) and downstream transcription factors (Gli1-3) using real-time RT-PCR. At seven days after injury, mRNAs for Patched1 and Gli1 were upregulated in response to injury, but displayed no upregulation in control retinas. Immunohistochemistry revealed that Patched1 and Gli1 proteins were localized to CD31-positive endothelial cells that cluster between the wounded retina and the pigment epithelium layer. Treatment with the hedgehog signaling inhibitor cyclopamine did not significantly decrease the size of the neovascularization areas, but the hedgehog agonist purmorphamine made the areas significantly larger than those in untreated retina. These results suggest that the hedgehog-signaling cascade may be a therapeutic target for age-related macular degeneration

The primary cilium coordinates early cardiogenesis and hedgehog signaling in cardiomyocyte differentiation

DEFF Research Database (Denmark)

Clement, Christian A; Kristensen, Stine G; Møllgård, Kjeld

2009-01-01

Defects in the assembly or function of primary cilia, which are sensory organelles, are tightly coupled to developmental defects and diseases in mammals. Here, we investigated the function of the primary cilium in regulating hedgehog signaling and early cardiogenesis. We report that the pluripotent...... P19.CL6 mouse stem cell line, which can differentiate into beating cardiomyocytes, forms primary cilia that contain essential components of the hedgehog pathway, including Smoothened, Patched-1 and Gli2. Knockdown of the primary cilium by Ift88 and Ift20 siRNA or treatment with cyclopamine...... development. These data support the conclusion that cardiac primary cilia are crucial in early heart development, where they partly coordinate hedgehog signaling....

The expression of Hedgehog genes (Ihh, Dhh) and Hedgehog target genes (Ptc1, Gli1, Coup-TfII) is affected by estrogenic stimuli in the uterus of immature female rats

International Nuclear Information System (INIS)

Katayama, Seiichi; Ashizawa, Koji; Gohma, Hiroshi; Fukuhara, Tadahiro; Narumi, Kazunori; Tsuzuki, Yasuhiro; Tatemoto, Hideki; Nakada, Tadashi; Nagai, Kenji

2006-01-01

The objective of this study was to investigate the effects of estrogen receptor (ER) agonists and an ER antagonist on the expression of Hedgehog genes (Indian hedgehog: Ihh; Desert hedgehog: Dhh) and Hedgehog target genes (Patched 1: Ptc1; glioma-associated oncogene homolog 1: Gli1; chicken ovalbumin upstream promoter transcription factor II: Coup-TfII) in the rat uterus. Immature female rats were administered once with 17α-ethynyl estradiol (EE, an ER agonist), propyl pyrazole triole (PPT, an ERα-selective agonist), diarylpropionitrile (DPN, an ERβ-selective agonist), or ICI 182,780 (an ER antagonist). Expression of mRNA for Ihh, Dhh, and Ptc1 was dose-dependently downregulated by EE in the uterus of immature rats, mediated by ER as confirmed by coadministration of ICI 182,780. The mRNA expression levels of Ptc1, Gli1, and Coup-TfII were simultaneously downregulated during the period in which the mRNA expression levels of Ihh and Dhh were downregulated in the uterus after administration of EE. PPT downregulated the transcription of Ihh, Dhh, Ptc1, Gli1, and Coup-TfII, indicating that expression of these genes was regulated by the ERα-dependent pathway. DPN also downregulated the transcription of Ihh and Dhh, although the effect was weaker than that of PPT, indicating that the regulation of uterine Ihh and Dhh transcription was also affected by the ERβ-dependent pathway. These results suggest that the expression of Hedgehog genes (Ihh, Dhh) and Hedgehog target genes (Ptc1, Gli1, Coup-TfII) is affected by estrogenic stimuli in the uterus of immature female rats

The expression of Hedgehog genes (Ihh, Dhh) and Hedgehog target genes (Ptc1, Gli1, Coup-TfII) is affected by estrogenic stimuli in the uterus of immature female rats.

Science.gov (United States)

Katayama, Seiichi; Ashizawa, Koji; Gohma, Hiroshi; Fukuhara, Tadahiro; Narumi, Kazunori; Tsuzuki, Yasuhiro; Tatemoto, Hideki; Nakada, Tadashi; Nagai, Kenji

2006-12-15

The objective of this study was to investigate the effects of estrogen receptor (ER) agonists and an ER antagonist on the expression of Hedgehog genes (Indian hedgehog: Ihh; Desert hedgehog: Dhh) and Hedgehog target genes (Patched 1: Ptc1; glioma-associated oncogene homolog 1: Gli1; chicken ovalbumin upstream promoter transcription factor II: Coup-TfII) in the rat uterus. Immature female rats were administered once with 17alpha-ethynyl estradiol (EE, an ER agonist), propyl pyrazole triole (PPT, an ERalpha-selective agonist), diarylpropionitrile (DPN, an ERbeta-selective agonist), or ICI 182,780 (an ER antagonist). Expression of mRNA for Ihh, Dhh, and Ptc1 was dose-dependently downregulated by EE in the uterus of immature rats, mediated by ER as confirmed by coadministration of ICI 182,780. The mRNA expression levels of Ptc1, Gli1, and Coup-TfII were simultaneously downregulated during the period in which the mRNA expression levels of Ihh and Dhh were downregulated in the uterus after administration of EE. PPT downregulated the transcription of Ihh, Dhh, Ptc1, Gli1, and Coup-TfII, indicating that expression of these genes was regulated by the ERalpha-dependent pathway. DPN also downregulated the transcription of Ihh and Dhh, although the effect was weaker than that of PPT, indicating that the regulation of uterine Ihh and Dhh transcription was also affected by the ERbeta-dependent pathway. These results suggest that the expression of Hedgehog genes (Ihh, Dhh) and Hedgehog target genes (Ptc1, Gli1, Coup-TfII) is affected by estrogenic stimuli in the uterus of immature female rats.

The Pathology of Wobbly Hedgehog Syndrome.

Science.gov (United States)

Díaz-Delgado, Josué; Whitley, Derick B; Storts, Ralph W; Heatley, Jill J; Hoppes, Sharman; Porter, Brian F

2018-01-01

Wobbly hedgehog syndrome (WHS) is a leading cause of neurologic disease in African pygmy hedgehogs (APHs; Atelerix albiventris). This study describes the signalment, clinical signs, gross, microscopic, and ultrastructural lesions of WHS in a cohort of 12 pet APHs. Microscopically, lesions consisted of status spongiosus of the white matter, typically bilateral and symmetrical, with myelin degeneration and loss that was accompanied by neuronal/axonal degeneration plus reactive microgliosis and mild, focal astrocytosis and astrogliosis. Lesions were most severe in the cerebellum and medulla oblongata, as well as cervical and thoracic spinal cord. Less affected areas were the corona radiata, corpus callosum, corpus striatum, internal capsule, and the mesencephalon. Ultrastructurally, the lesions consisted of splitting of the myelin sheath at the intraperiod line with subsequent focal expansion, resulting in status spongiosus, disruption, dilatation, rhexis, and phagocytosis. Based on these results, WHS is best described as a "spongy myelinopathy" with widespread central nervous system involvement.

Ticks and Fleas Infestation on East Hedgehogs (Erinaceus concolor in Van Province, Eastern Region of Turkey

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Yaşar Goz

2015-10-01

Full Text Available Background: Ixodid ticks (Acari: İxodidae and fleas (Siphonaptera are the major vectors of pathogens threatening animals and human healths. The aim of our study was to detect the infestation rates of East Hedgehogs (Erinaceus concolor with ticks and fleas in Van Province, eastern region of Turkey.Methods: We examined fleas and ticks infestation patterns in 21 hedgehogs, collected from three suburbs with the greater of number gardens. In order to estimate flea and tick infestation of hedgehogs, we immobilized the ectoparasites by treatment the body with a insecticide trichlorphon (Neguvon®-Bayer.Results: On the hedgehogs, 60 ixodid ticks and 125 fleas were detected. All of the ixodid ticks were Rhipicephalus turanicus and all of the fleas were Archaeopsylla erinacei. Infestation rate for ticks and fleas was detected 66.66 % and 100 %, respectively.Conclusion: We detected ticks (R. turanicus and fleas (A. erinacei in hedgehogs at fairly high rates. Since many ticks and fleas species may harbor on hedgehogs and transmit some tick-borne and flea-borne patogens, this results are the important in terms of veterinary and public health. 

Identification and Characterization of Sterol Acyltransferases Responsible for Steryl Ester Biosynthesis in Tomato

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Juan A. Lara

2018-05-01

Full Text Available Steryl esters (SEs serve as a storage pool of sterols that helps to maintain proper levels of free sterols (FSs in cell membranes throughout plant growth and development, and participates in the recycling of FSs and fatty acids released from cell membranes in aging tissues. SEs are synthesized by sterol acyltransferases, a family of enzymes that catalyze the transfer of fatty acil groups to the hydroxyl group at C-3 position of the sterol backbone. Sterol acyltransferases are categorized into acyl-CoA:sterol acyltransferases (ASAT and phospholipid:sterol acyltransferases (PSAT depending on whether the fatty acyl donor substrate is a long-chain acyl-CoA or a phospolipid. Until now, only Arabidopsis ASAT and PSAT enzymes (AtASAT1 and AtPSAT1 have been cloned and characterized in plants. Here we report the identification, cloning, and functional characterization of the tomato (Solanum lycopersicum cv. Micro-Tom orthologs. SlPSAT1 and SlASAT1 were able to restore SE to wild type levels in the Arabidopsis psat1-2 and asat1-1 knock-out mutants, respectively. Expression of SlPSAT1 in the psat1-2 background also prevented the toxicity caused by an external supply of mevalonate and the early senescence phenotype observed in detached leaves of this mutant, whereas expression of SlASAT1 in the asat1-1 mutant revealed a clear substrate preference of the tomato enzyme for the sterol precursors cycloartenol and 24-methylene cycloartanol. Subcellular localization studies using fluorescently tagged SlPSAT1 and SlASAT1 proteins revealed that SlPSAT1 localize in cytoplasmic lipid droplets (LDs while, in contrast to the endoplasmic reticulum (ER localization of AtASAT1, SlASAT1 resides in the plasma membrane (PM. The possibility that PM-localized SlASAT1 may act catalytically in trans on their sterol substrates, which are presumably embedded in the ER membrane, is discussed. The widespread expression of SlPSAT1 and SlASAT1 genes in different tomato organs together

Hedgehog pathway regulators influence cervical cancer cell proliferation, survival and migration

Energy Technology Data Exchange (ETDEWEB)

Samarzija, Ivana [Ecole Polytechnique Federale Lausanne (EPFL), Department of Life Sciences, Swiss Institute for Experimental Cancer Research (ISREC), 1015 Lausanne (Switzerland); Beard, Peter, E-mail: peter.beard@epfl.ch [Ecole Polytechnique Federale Lausanne (EPFL), Department of Life Sciences, Swiss Institute for Experimental Cancer Research (ISREC), 1015 Lausanne (Switzerland)

2012-08-17

Highlights: Black-Right-Pointing-Pointer Unknown cellular mutations complement papillomavirus-induced carcinogenesis. Black-Right-Pointing-Pointer Hedgehog pathway components are expressed by cervical cancer cells. Black-Right-Pointing-Pointer Hedgehog pathway activators and inhibitors regulate cervical cancer cell biology. Black-Right-Pointing-Pointer Cell immortalization by papillomavirus and activation of Hedgehog are independent. -- Abstract: Human papillomavirus (HPV) infection is considered to be a primary hit that causes cervical cancer. However, infection with this agent, although needed, is not sufficient for a cancer to develop. Additional cellular changes are required to complement the action of HPV, but the precise nature of these changes is not clear. Here, we studied the function of the Hedgehog (Hh) signaling pathway in cervical cancer. The Hh pathway can have a role in a number of cancers, including those of liver, lung and digestive tract. We found that components of the Hh pathway are expressed in several cervical cancer cell lines, indicating that there could exists an autocrine Hh signaling loop in these cells. Inhibition of Hh signaling reduces proliferation and survival of the cervical cancer cells and induces their apoptosis as seen by the up-regulation of the pro-apoptotic protein cleaved caspase 3. Our results indicate that Hh signaling is not induced directly by HPV-encoded proteins but rather that Hh-activating mutations are selected in cells initially immortalized by HPV. Sonic Hedgehog (Shh) ligand induces proliferation and promotes migration of the cervical cancer cells studied. Together, these results indicate pro-survival and protective roles of an activated Hh signaling pathway in cervical cancer-derived cells, and suggest that inhibition of this pathway may be a therapeutic option in fighting cervical cancer.

Hedgehog pathway regulators influence cervical cancer cell proliferation, survival and migration

International Nuclear Information System (INIS)

Samarzija, Ivana; Beard, Peter

2012-01-01

Highlights: ► Unknown cellular mutations complement papillomavirus-induced carcinogenesis. ► Hedgehog pathway components are expressed by cervical cancer cells. ► Hedgehog pathway activators and inhibitors regulate cervical cancer cell biology. ► Cell immortalization by papillomavirus and activation of Hedgehog are independent. -- Abstract: Human papillomavirus (HPV) infection is considered to be a primary hit that causes cervical cancer. However, infection with this agent, although needed, is not sufficient for a cancer to develop. Additional cellular changes are required to complement the action of HPV, but the precise nature of these changes is not clear. Here, we studied the function of the Hedgehog (Hh) signaling pathway in cervical cancer. The Hh pathway can have a role in a number of cancers, including those of liver, lung and digestive tract. We found that components of the Hh pathway are expressed in several cervical cancer cell lines, indicating that there could exists an autocrine Hh signaling loop in these cells. Inhibition of Hh signaling reduces proliferation and survival of the cervical cancer cells and induces their apoptosis as seen by the up-regulation of the pro-apoptotic protein cleaved caspase 3. Our results indicate that Hh signaling is not induced directly by HPV-encoded proteins but rather that Hh-activating mutations are selected in cells initially immortalized by HPV. Sonic Hedgehog (Shh) ligand induces proliferation and promotes migration of the cervical cancer cells studied. Together, these results indicate pro-survival and protective roles of an activated Hh signaling pathway in cervical cancer-derived cells, and suggest that inhibition of this pathway may be a therapeutic option in fighting cervical cancer.

The hedgehog-signaling pathway is repressed during the osteogenic differentiation of dental follicle cells

DEFF Research Database (Denmark)

Morsczeck, Christian; Reck, A; Beck, H C

2017-01-01

of repressors of the hedgehog-signaling pathway such as Patched 1 (PTCH1), Suppressor of Fused (SUFU), and Parathyroid Hormone-Related Peptide (PTHrP). Previous studies suggested that hedgehog proteins induce the osteogenic differentiation of mesenchymal stem cells via a paracrine pathway. Indian hedgehog (IHH......) induced the expression of the osteogenic transcription factor RUNX2. However, a supplementation of the BMP2-based osteogenic differentiation medium with IHH did not induce the expression of RUNX2. Moreover, IHH inhibited slightly the ALP activity and the mineralization of osteogenic-differentiated DFCs...

First report of acariasis by Caparinia tripilis in African hedgehogs, (Atelerix albiventris), in Costa Rica

OpenAIRE

Moreira, Andrés; Troyo, Adriana; Calderón-Arguedas, Olger

2013-01-01

The African hedgehog is one of the newly imported exotic pets which have been observed with increasing regularity in veterinary clinics in Costa Rica. Despite their popularity, information about their diseases is scarce. Within skin diseases of hedgehogs, mange caused by Capariniaspp. is a common diagnosis in other countries. Two adult African hedgehogs, one male and one female, were brought to a private clinic in Heredia, Costa Rica, with chronic pruritic dermatitis, scabs, nearly complete l...

First report of acariasis by Caparinia tripilis in African hedgehogs, (Atelerix albiventris), in Costa Rica

OpenAIRE

Moreira,Andrés; Troyo,Adriana; Calderón-Arguedas,Olger

2013-01-01

The African hedgehog is one of the newly imported exotic pets which have been observed with increasing regularity in veterinary clinics in Costa Rica. Despite their popularity, information about their diseases is scarce. Within skin diseases of hedgehogs, mange caused by Caparinia spp. is a common diagnosis in other countries. Two adult African hedgehogs, one male and one female, were brought to a private clinic in Heredia, Costa Rica, with chronic pruritic dermatitis, scabs, nearly complete ...

In vivo imaging of Hedgehog pathway activation with a nuclear fluorescent reporter.

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John K Mich

Full Text Available The Hedgehog (Hh pathway is essential for embryonic development and tissue regeneration, and its dysregulation can lead to birth defects and tumorigenesis. Understanding how this signaling mechanism contributes to these processes would benefit from an ability to visualize Hedgehog pathway activity in live organisms, in real time, and with single-cell resolution. We report here the generation of transgenic zebrafish lines that express nuclear-localized mCherry fluorescent protein in a Gli transcription factor-dependent manner. As demonstrated by chemical and genetic perturbations, these lines faithfully report Hedgehog pathway state in individual cells and with high detection sensitivity. They will be valuable tools for studying dynamic Gli-dependent processes in vertebrates and for identifying new chemical and genetic regulators of the Hh pathway.

Purification of peroxisomal acyl-CoA: dihydroxyacetonephosphate acyltransferase from human placenta

NARCIS (Netherlands)

Ofman, R.; Wanders, R. J.

1994-01-01

The peroxisomal enzyme acyl-CoA:dihydroxyacetonephosphate acyltransferase (DHAPAT) was extracted from human placental membranes using CHAPS as a detergent in the presence of 1 M KCl. Prior to assay dipalmitoylphosphatidylcholine was added to the sample as eluted from the various columns in order to

Cytoarchitectonic and quantitative Golgi study of the hedgehog supraoptic nucleus.

Science.gov (United States)

Caminero, A A; Machín, C; Sanchez-Toscano, F

1992-01-01

A cytoarchitectural study was made of the supraoptic nucleus (SON) of the hedgehog with special attention to the quantitative comparison of its main neuronal types. The main purposes were (1) to relate the characteristics of this nucleus in the hedgehog (a primitive mammalian insectivorous brain) with those in the SONs of more evolutionarily advanced species; (2) to identify quantitatively the dendritic fields of the main neuronal types in the hedgehog SON and to study their synaptic connectivity. From a descriptive standpoint, 3 neuronal types were found with respect to the number of dendritic stems arising from the neuronal soma: bipolar neurons (48%), multipolar neurons (45.5%) and monopolar neurons (6.5%). Within the multipolar type 2 subtypes could be distinguished, taking into account the number of dendritic spines: (a) with few spines (93%) and (b) very spiny (7%). These results indicate that the hedgehog SON is similar to that in other species except for the very spiny neurons, the significance of which is discussed. In order to characterise the main types more satisfactorily (bipolar and multipolars with few spines) we undertook a quantitative Golgi study of their dendritic fields. Although the patterns of the dendritic field are similar in both neuronal types, the differences in the location of their connectivity can reflect functional changes and alterations in relation to the synaptic afferences. Images Fig. 2 Fig. 3 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 PMID:1452481

Ophthalmological abnormalities in wild European hedgehogs ...

African Journals Online (AJOL)

In this study we aimed to examine wild European hedgehogs (Erinaceus europaeus) in rescue centres and to determine ocular abnormalities in this animal population. Three hundred animals varying in age from 2 months to 5 years were examined, 147 being male and 153 female. All animals were evaluated with direct ...

Diacylglycerol Acyltransferase-2 (DGAT2) and Monoacylglycerol Acyltransferase-2 (MGAT2) Interact to Promote Triacylglycerol Synthesis*

Science.gov (United States)

Jin, Youzhi; McFie, Pamela J.; Banman, Shanna L.; Brandt, Curtis; Stone, Scot J.

2014-01-01

Acyl CoA:1,2-diacylglycerol acyltransferase (DGAT)-2 is an integral membrane protein that catalyzes triacylglycerol (TG) synthesis using diacylglycerol and fatty acyl CoA as substrates. DGAT2 resides in the endoplasmic reticulum (ER), but when cells are incubated with fatty acids, DGAT2 interacts with lipid droplets presumably to catalyze localized TG synthesis for lipid droplet expansion. Previous studies have shown that DGAT2 interacts with proteins that synthesize its fatty acyl CoA substrates. In this study, we provide additional evidence that DGAT2 is present in a protein complex. Using a chemical cross-linker, disuccinimidyl suberate (DSS), we demonstrated that DGAT2 formed a dimer and was also part of a protein complex of ∼650 kDa, both in membranes and on lipid droplets. Using co-immunoprecipitation experiments and an in situ proximity ligation assay, we found that DGAT2 interacted with monoacylglycerol acyltransferase (MGAT)-2, an enzyme that catalyzes the synthesis of diacylglycerol. Deletion mutagenesis showed that the interaction with MGAT2 was dependent on the two transmembrane domains of DGAT2. No significant interaction of DGAT2 with lipin1, another enzyme that synthesizes diacylglycerol, could be detected. When co-expressed in cells, DGAT2 and MGAT2 co-localized in the ER and on lipid droplets. Co-expression also resulted in increased TG storage compared with expression of DGAT2 or MGAT2 alone. Incubating McArdle rat hepatoma RH7777 cells with 2-monoacylglycerol caused DGAT2 to translocate to lipid droplets. This also led to the formation of large cytosolic lipid droplets, characteristic of DGAT2, but not DGAT1, and indicated that DGAT2 can utilize monoacylglycerol-derived diacylglycerol. These findings suggest that the interaction of DGAT2 and MGAT2 serves to channel lipid substrates efficiently for TG biosynthesis. PMID:25164810

Smoothened-antagonists reverse homogentisic acid-induced alterations of Hedgehog signaling and primary cilium length in alkaptonuria.

Science.gov (United States)

Gambassi, Silvia; Geminiani, Michela; Thorpe, Stephen D; Bernardini, Giulia; Millucci, Lia; Braconi, Daniela; Orlandini, Maurizio; Thompson, Clare L; Petricci, Elena; Manetti, Fabrizio; Taddei, Maurizio; Knight, Martin M; Santucci, Annalisa

2017-11-01

Alkaptonuria (AKU) is an ultra-rare genetic disease, in which the accumulation of a toxic metabolite, homogentisic acid (HGA) leads to the systemic development of ochronotic aggregates. These aggregates cause severe complications mainly at the level of joints with extensive degradation of the articular cartilage. Primary cilia have been demonstrated to play an essential role in development and the maintenance of articular cartilage homeostasis, through their involvement in mechanosignaling and Hedgehog signaling pathways. Hedgehog signaling has been demonstrated to be activated in osteoarthritis (OA) and to drive cartilage degeneration in vivo. The numerous similarities between OA and AKU suggest that primary cilia Hedgehog signaling may also be altered in AKU. Thus, we characterized an AKU cellular model in which healthy chondrocytes were treated with HGA (66 µM) to replicate AKU cartilage pathology. We investigated the degree of activation of the Hedgehog signaling pathway and how treatment with inhibitors of the receptor Smoothened (Smo) influenced Hedgehog activation and primary cilia structure. The results obtained in this work provide a further step in the comprehension of the pathophysiological features of AKU, suggesting a potential therapeutic approach to modulate AKU cartilage degradation processes through manipulation of the Hedgehog pathway. © 2016 Wiley Periodicals, Inc.

G-Protein Gαs controls medulloblastoma initiation by suppressing sonic hedgehog signaling.

Science.gov (United States)

He, Xuelian; Lu, Q Richard

2015-01-01

We identify Gαs as a novel tumor suppressor in medulloblastoma that functions principally by inhibition of sonic hedgehog signaling. Gαs not only stimulates cyclic adenosine monophosphate (cAMP)-dependent signaling but also inhibits ciliary trafficking of hedgehog components. Elevation of cAMP inhibits medulloblastoma growth and augments inhibition of smoothened to decrease tumor cell proliferation, thus highlighting Gαs as a potential therapeutic target.

Hedgehog Signalling is Downregulated in Celiac Disease

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Rui Liang

2013-01-01

Full Text Available BACKGROUND: Celiac disease (CD is a common autoimmune disorder of the small intestine that occurs in genetically predisposed individuals. Animal studies have suggested that the hedgehog (Hh signalling pathway is involved in gut inflammation, injury and repair.

An Integrated Approach Identifies Nhlh1 and Insm1 as Sonic Hedgehog-regulated Genes in Developing Cerebellum and Medulloblastoma

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Enrico De Smaele

2008-01-01

Full Text Available Medulloblastoma (MB is the most common malignant brain tumor of childhood arising from deregulated cerebellar development. Sonic Hedgehog (Shh pathway plays a critical role in cerebellar development and its aberrant expression has been identified in MB. Gene expression profiling of cerebella from 1- to 14-day-old mice unveiled a cluster of genes whose expression correlates with the levels of Hedgehog (HH activity. From this cluster, we identified Insm1 and Nhlh1/NSCL1 as novel HH targets induced by Shh treatment in cultured cerebellar granule cell progenitors. Nhlh1 promoter was found to be bound and activated by Gli1 transcription factor. Remarkably, the expression of these genes is also upregulated in mouse and human HH-dependent MBs, suggesting that they may be either a part of the HH-induced tumorigenic process or a specific trait of HH-dependent tumor cells.

Definition of critical periods for Hedgehog pathway antagonist-induced holoprosencephaly, cleft lip, and cleft palate.

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Galen W Heyne

Full Text Available The Hedgehog (Hh signaling pathway mediates multiple spatiotemporally-specific aspects of brain and face development. Genetic and chemical disruptions of the pathway are known to result in an array of structural malformations, including holoprosencephaly (HPE, clefts of the lip with or without cleft palate (CL/P, and clefts of the secondary palate only (CPO. Here, we examined patterns of dysmorphology caused by acute, stage-specific Hh signaling inhibition. Timed-pregnant wildtype C57BL/6J mice were administered a single dose of the potent pathway antagonist vismodegib at discrete time points between gestational day (GD 7.0 and 10.0, an interval approximately corresponding to the 15th to 24th days of human gestation. The resultant pattern of facial and brain dysmorphology was dependent upon stage of exposure. Insult between GD7.0 and GD8.25 resulted in HPE, with peak incidence following exposure at GD7.5. Unilateral clefts of the lip extending into the primary palate were also observed, with peak incidence following exposure at GD8.875. Insult between GD9.0 and GD10.0 resulted in CPO and forelimb abnormalities. We have previously demonstrated that Hh antagonist-induced cleft lip results from deficiency of the medial nasal process and show here that CPO is associated with reduced growth of the maxillary-derived palatal shelves. By defining the critical periods for the induction of HPE, CL/P, and CPO with fine temporal resolution, these results provide a mechanism by which Hh pathway disruption can result in "non-syndromic" orofacial clefting, or HPE with or without co-occurring clefts. This study also establishes a novel and tractable mouse model of human craniofacial malformations using a single dose of a commercially available and pathway-specific drug.

The Binding Mode of the Sonic Hedgehog Inhibitor Robotnikinin, a Combined Docking and QM/MM MD Study

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Manuel Hitzenberger

2017-10-01

Full Text Available Erroneous activation of the Hedgehog pathway has been linked to a great amount of cancerous diseases and therefore a large number of studies aiming at its inhibition have been carried out. One leverage point for novel therapeutic strategies targeting the proteins involved, is the prevention of complex formation between the extracellular signaling protein Sonic Hedgehog and the transmembrane protein Patched 1. In 2009 robotnikinin, a small molecule capable of binding to and inhibiting the activity of Sonic Hedgehog has been identified, however in the absence of X-ray structures of the Sonic Hedgehog-robotnikinin complex, the binding mode of this inhibitor remains unknown. In order to aid with the identification of novel Sonic Hedgehog inhibitors, the presented investigation elucidates the binding mode of robotnikinin by performing an extensive docking study, including subsequent molecular mechanical as well as quantum mechanical/molecular mechanical molecular dynamics simulations. The attained configurations enabled the identification of a number of key protein-ligand interactions, aiding complex formation and providing stabilizing contributions to the binding of the ligand. The predicted structure of the Sonic Hedgehog-robotnikinin complex is provided via a PDB file as Supplementary Material and can be used for further reference.

Integument Mycobiota of Wild European Hedgehogs (Erinaceus europaeus) from Catalonia, Spain.

Science.gov (United States)

Molina-López, R A; Adelantado, C; Arosemena, E L; Obón, E; Darwich, L; Calvo, M A

2012-01-01

There are some reports about the risk of manipulating wild hedgehogs since they can be reservoirs of potential zoonotic agents like dermatophytes. The aim of this study was to describe the integument mycobiota, with special attention to dermatophytes of wild European hedgehogs. Samples from spines and fur were cultured separately in Sabouraud dextrose agar (SDA) with antibiotic and dermatophyte test medium (DTM) plates. Nineteen different fungal genera were isolated from 91 cultures of 102 hedgehogs. The most prevalent genera were Cladosporium (79.1%), Penicillium (74.7%), Alternaria (64.8%), and Rhizopus (63.7%). A lower prevalence of Aspergillus (P = 0,035; χ (2) = 8,633) and Arthrinium (P = 0,043; χ (2) = 8,173) was isolated during the spring time and higher frequencies of Fusarium (P = 0,015; χ (2) = 10,533) during the autumn. The prevalence of Acremonium was significantly higher in young animals (70%, 26/37) than in adults (30%, 11/37) (P = 0,019; χ (2) = 5,915). Moreover, the majority of the saprophytic species that grew at the SDA culture were also detected at the DTM. Finally, no cases of ringworm were diagnosed and no dermatophytes spp. were isolated. Concluding, this study provides the first description of fungal mycobiota of the integument of wild European hedgehogs in Spain, showing a large number of saprophytic species and the absence of dermatophytes.

The LINKS motif zippers trans-acyltransferase polyketide synthase assembly lines into a biosynthetic megacomplex.

Science.gov (United States)

Gay, Darren C; Wagner, Drew T; Meinke, Jessica L; Zogzas, Charles E; Gay, Glen R; Keatinge-Clay, Adrian T

2016-03-01

Polyketides such as the clinically-valuable antibacterial agent mupirocin are constructed by architecturally-sophisticated assembly lines known as trans-acyltransferase polyketide synthases. Organelle-sized megacomplexes composed of several copies of trans-acyltransferase polyketide synthase assembly lines have been observed by others through transmission electron microscopy to be located at the Bacillus subtilis plasma membrane, where the synthesis and export of the antibacterial polyketide bacillaene takes place. In this work we analyze ten crystal structures of trans-acyltransferase polyketide synthases ketosynthase domains, seven of which are reported here for the first time, to characterize a motif capable of zippering assembly lines into a megacomplex. While each of the three-helix LINKS (Laterally-INteracting Ketosynthase Sequence) motifs is observed to similarly dock with a spatially-reversed copy of itself through hydrophobic and ionic interactions, the amino acid sequences of this motif are not conserved. Such a code is appropriate for mediating homotypic contacts between assembly lines to ensure the ordered self-assembly of a noncovalent, yet tightly-knit, enzymatic network. LINKS-mediated lateral interactions would also have the effect of bolstering the vertical association of the polypeptides that comprise a polyketide synthase assembly line. Copyright © 2015 Elsevier Inc. All rights reserved.

Morphometrics of foramen magnum in African four-toed hedgehog (Atelerix albiventris).

Science.gov (United States)

Girgiri, I; Olopade, J O; Yahaya, A

The purpose of this study was to examine the morphometry of the foramen magnum of African four-toed hedgehog (Atelerix albiventris) in Maiduguri. Fourteen hedgehog skulls (7 male and 7 female each) were used for this study. The overall mean value of foramen magnum height and width were 0.51 ± 0.05 cm and 0.64 ± 0.04 cm while occipital condylar and interparacondylar widths were 1.00 ± 0.12 cm and 1.62 ± 0.07 cm, respectively. There was no significant difference between the two sexes. The foramen magnum index was 83.4 ± 5.51 cm in males and was significantly higher than 76.3 ± 6.37 cm observed in females. The presences of dorsal notches (occipital dysplasia) were observed, that were of three distinct types. It is envisaged, that the study will provide a valuable database on the anatomy of foramen magnum of hedgehogs in Nigeria for morphological, neurological, zooarchaeological, and comparative anatomical studies.

Soybean oil biosynthesis: role of diacylglycerol acyltransferases.

Science.gov (United States)

Li, Runzhi; Hatanaka, Tomoko; Yu, Keshun; Wu, Yongmei; Fukushige, Hirotada; Hildebrand, David

2013-03-01

Diacylglycerol acyltransferase (DGAT) catalyzes the acyl-CoA-dependent acylation of sn-1,2-diacylglycerol to form seed oil triacylglycerol (TAG). To understand the features of genes encoding soybean (Glycine max) DGATs and possible roles in soybean seed oil synthesis and accumulation, two full-length cDNAs encoding type 1 diacylglycerol acyltransferases (GmDGAT1A and GmDGAT1B) were cloned from developing soybean seeds. These coding sequences share identities of 94 % and 95 % in protein and DNA sequences. The genomic architectures of GmDGAT1A and GmDGAT1B both contain 15 introns and 16 exons. Differences in the lengths of the first exon and most of the introns were found between GmDGAT1A and GmDGAT1B genomic sequences. Furthermore, detailed in silico analysis revealed a third predicted DGAT1, GmDGAT1C. GmDGAT1A and GmDGAT1B were found to have similar activity levels and substrate specificities. Oleoyl-CoA and sn-1,2-diacylglycerol were preferred substrates over vernoloyl-CoA and sn-1,2-divernoloylglycerol. Both transcripts are much more abundant in developing seeds than in other tissues including leaves, stem, roots, and flowers. Both soybean DGAT1A and DGAT1B are highly expressed at developing seed stages of maximal TAG accumulation with DGAT1B showing highest expression at somewhat later stages than DGAT1A. DGAT1A and DGAT1B show expression profiles consistent with important roles in soybean seed oil biosynthesis and accumulation.

Expression of tung seed diacylglycerol acyltransferases (DGAT) in E. coli and yeast

Science.gov (United States)

Diacylglycerol acyltransferases (DGATs) catalyze the last step of triacylglycerol (TAG) biosynthesis in eukaryotic organisms. Plants and animals deficient in DGATs accumulate less TAG, resist obesity, and/or lack milk secretion. Over-expression of the DGATs increases TAG content in seeds and other t...

Hedgehogs and Foxes at the Crossroads: Leadership and Diversity at the University of California

Science.gov (United States)

González, Cristina

2011-01-01

Following Clark Kerr's distinction between hedgehogs, or visionary leaders who know "one big thing," and foxes, or shrewd leaders who know "many things," this paper studies Kerr, an archetypical hedgehog, and David Gardner, a quintessential fox, as models for these two types of leaders. The paper also analyzes the hedgehog…

Home Range Characteristics and Habitat Selection by Daurian Hedgehogs ( Mesechinus dauuricus in Ikh Nart Nature Reserve, Mongolia

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Mirka Zapletal

2012-12-01

Full Text Available We examined home range characteristics and habitat selection of Daurian hedgehogs in Ikh Nart Nature Reserve, Mongolia. Home ranges of hedgehogs varied from 113.15 ha to 2,171.97 ha, and were larger in early summer than late summer. Hedgehogs showed relative preference for rocky outcrops and low-density shrub habitats, and relative avoidance of high- density shrub areas. Habitat selection also changed between early and late summer, shifting to greater use of low-density shrub areas and decreased use of forb-dominated short grass. Our baseline data on home ranges and habitat selection expand understanding of hedgehog ecology and provide guidance for future management decisions in Ikh Nart Nature Reserve and elsewhere in Mongolia.

Hedgehog Signaling in Endochondral Ossification

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Shinsuke Ohba

2016-06-01

Full Text Available Hedgehog (Hh signaling plays crucial roles in the patterning and morphogenesis of various organs within the bodies of vertebrates and insects. Endochondral ossification is one of the notable developmental events in which Hh signaling acts as a master regulator. Among three Hh proteins in mammals, Indian hedgehog (Ihh is known to work as a major Hh input that induces biological impact of Hh signaling on the endochondral ossification. Ihh is expressed in prehypertrophic and hypertrophic chondrocytes of developing endochondral bones. Genetic studies so far have demonstrated that the Ihh-mediated activation of Hh signaling synchronizes chondrogenesis and osteogenesis during endochondral ossification by regulating the following processes: (1 chondrocyte differentiation; (2 chondrocyte proliferation; and (3 specification of bone-forming osteoblasts. Ihh not only forms a negative feedback loop with parathyroid hormone-related protein (PTHrP to maintain the growth plate length, but also directly promotes chondrocyte propagation. Ihh input is required for the specification of progenitors into osteoblast precursors. The combinatorial approaches of genome-wide analyses and mouse genetics will facilitate understanding of the regulatory mechanisms underlying the roles of Hh signaling in endochondral ossification, providing genome-level evidence of the potential of Hh signaling for the treatment of skeletal disorders.

Hedgehog Signaling in Endochondral Ossification

Science.gov (United States)

Ohba, Shinsuke

2016-01-01

Hedgehog (Hh) signaling plays crucial roles in the patterning and morphogenesis of various organs within the bodies of vertebrates and insects. Endochondral ossification is one of the notable developmental events in which Hh signaling acts as a master regulator. Among three Hh proteins in mammals, Indian hedgehog (Ihh) is known to work as a major Hh input that induces biological impact of Hh signaling on the endochondral ossification. Ihh is expressed in prehypertrophic and hypertrophic chondrocytes of developing endochondral bones. Genetic studies so far have demonstrated that the Ihh-mediated activation of Hh signaling synchronizes chondrogenesis and osteogenesis during endochondral ossification by regulating the following processes: (1) chondrocyte differentiation; (2) chondrocyte proliferation; and (3) specification of bone-forming osteoblasts. Ihh not only forms a negative feedback loop with parathyroid hormone-related protein (PTHrP) to maintain the growth plate length, but also directly promotes chondrocyte propagation. Ihh input is required for the specification of progenitors into osteoblast precursors. The combinatorial approaches of genome-wide analyses and mouse genetics will facilitate understanding of the regulatory mechanisms underlying the roles of Hh signaling in endochondral ossification, providing genome-level evidence of the potential of Hh signaling for the treatment of skeletal disorders. PMID:29615586

Comparison of human plasma low- and high-density lipoproteins as substrates for lecithin: cholesterol acyltransferase.

Science.gov (United States)

Barter, P J; Hopkins, G J; Gorjatschko, L

1984-01-17

A recent observation that lecithin: cholesterol acyltransferase (EC 2.3.1.43) interacts with both low-density lipoproteins (LDL) and high-density lipoproteins (HDL) in human plasma is in apparent conflict with an earlier finding that the purified enzyme, while highly reactive with isolated HDL, was only minimally reactive with LDL. There is evidence, however, that lecithin: cholesterol acyltransferase may exist physiologically as a component of a complex with other proteins and that studies with the isolated enzyme may therefore provide misleading results. Consequently, interactions of the enzyme with isolated human lipoproteins have been re-examined in incubations containing lecithin: cholesterol acyltransferase as a component of human lipoprotein-free plasma in which a physiologically active complex of the enzyme with other proteins may have been preserved. In this system there was a ready esterification of the free cholesterol associated with both LDL and HDL-subfraction 3 (HDL3) in reactions that obeyed typical enzyme-saturation kinetics. For a given preparation of lipoprotein-free plasma the Vmax values with LDL and with HDL3 were virtually identical. The apparent Km for free cholesterol associated with HDL3 was 5.6 X 10(-5) M, while for that associated with LDL it was 4.1 X 10(-4) M. This implied that, in terms of free cholesterol concentration, the affinity of HDL3 for lecithin: cholesterol acyltransferase was about 7-times greater than that of LDL. When expressed in terms of lipoprotein particle concentration, however, it was apparent that the affinity of LDL for the enzyme was considerably greater than that of HDL3. When the lipoprotein fractions were equated in terms of lipoprotein surface area, the apparent affinities of the two fractions for the enzyme were found to be comparable.

Activities of acyl-CoA:diacylglycerol acyltransferase (DGAT) and phospholipid:diacylglycerol acyltransferase (PDAT) in microsomal preparations of developing sunflower and safflower seeds.

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Banaś, Walentyna; Sanchez Garcia, Alicia; Banaś, Antoni; Stymne, Sten

2013-06-01

The last step in triacylglycerols (TAG) biosynthesis in oil seeds, the acylation of diacylglycerols (DAG), is catalysed by two types of enzymes: the acyl-CoA:diacylglycerol acyltransferase (DGAT) and phospholipid:diacylglycerol acyltransferase (PDAT). The relative contribution of these enzymes in the synthesis of TAG has not yet been defined in any plant tissue. In the presented work, microsomal preparations were obtained from sunflower and safflower seeds at different stages of development and used in DGAT and PDAT enzyme assays. The ratio between PDAT and DGAT activity differed dramatically between the two different species. DGAT activities were measured with two different acyl acceptors and assay methods using two different acyl-CoAs, and in all cases the ratio of PDAT to DGAT activity was significantly higher in safflower than sunflower. The sunflower DGAT, measured by both methods, showed significant higher activity with 18:2-CoA than with 18:1-CoA, whereas the opposite specificity was seen with the safflower enzyme. The specificities of PDAT on the other hand, were similar in both species with 18:2-phosphatidylcholine being a better acyl donor than 18:1-PC and with acyl groups at the sn-2 position utilised about fourfold the rate of the sn-1 position. No DAG:DAG transacylase activity could be detected in the microsomal preparations.

The generalized hedgehog and the projected chiral soliton model

International Nuclear Information System (INIS)

Fiolhais, M.; Kernforschungsanlage Juelich G.m.b.H.; Goeke, K.; Bochum Univ.; Gruemmer, F.; Urbano, J.N.

1988-01-01

The linear chiral soliton model with quark fields and elementary pion and sigma fields is solved in order to describe static properties of the nucleon and the delta resonance. To this end a Fock state of the system is constructed which consists of three valence quarks in a 1s orbit with a generalized hedgehog spin-flavour configuration cosηvertical strokeu↓> - sin ηvertical stroked↑>. Coherent states are used to provide a quantum description for the mesonic parts of the total wave function. The corresponding classical pion field also exhibits a generalized hedgehog structure. Various nucleon properties are calculated. These include proton and neutron charge raii, and the mangnetic moment of the proton for which experiment is obtained. (orig./HSI)

Diacylglycerol acyltransferase-2 (DGAT2) and monoacylglycerol acyltransferase-2 (MGAT2) interact to promote triacylglycerol synthesis.

Science.gov (United States)

Jin, Youzhi; McFie, Pamela J; Banman, Shanna L; Brandt, Curtis; Stone, Scot J

2014-10-10

Acyl CoA:1,2-diacylglycerol acyltransferase (DGAT)-2 is an integral membrane protein that catalyzes triacylglycerol (TG) synthesis using diacylglycerol and fatty acyl CoA as substrates. DGAT2 resides in the endoplasmic reticulum (ER), but when cells are incubated with fatty acids, DGAT2 interacts with lipid droplets presumably to catalyze localized TG synthesis for lipid droplet expansion. Previous studies have shown that DGAT2 interacts with proteins that synthesize its fatty acyl CoA substrates. In this study, we provide additional evidence that DGAT2 is present in a protein complex. Using a chemical cross-linker, disuccinimidyl suberate (DSS), we demonstrated that DGAT2 formed a dimer and was also part of a protein complex of ∼ 650 kDa, both in membranes and on lipid droplets. Using co-immunoprecipitation experiments and an in situ proximity ligation assay, we found that DGAT2 interacted with monoacylglycerol acyltransferase (MGAT)-2, an enzyme that catalyzes the synthesis of diacylglycerol. Deletion mutagenesis showed that the interaction with MGAT2 was dependent on the two transmembrane domains of DGAT2. No significant interaction of DGAT2 with lipin1, another enzyme that synthesizes diacylglycerol, could be detected. When co-expressed in cells, DGAT2 and MGAT2 co-localized in the ER and on lipid droplets. Co-expression also resulted in increased TG storage compared with expression of DGAT2 or MGAT2 alone. Incubating McArdle rat hepatoma RH7777 cells with 2-monoacylglycerol caused DGAT2 to translocate to lipid droplets. This also led to the formation of large cytosolic lipid droplets, characteristic of DGAT2, but not DGAT1, and indicated that DGAT2 can utilize monoacylglycerol-derived diacylglycerol. These findings suggest that the interaction of DGAT2 and MGAT2 serves to channel lipid substrates efficiently for TG biosynthesis. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

The phylogenetic relationships of insectivores with special reference to the lesser hedgehog tenrec as inferred from the complete sequence of their mitochondrial genome.

Science.gov (United States)

Nikaido, Masato; Cao, Ying; Okada, Norihiro; Hasegawa, Masami

2003-02-01

The complete mitochondrial genome of a lesser hedgehog tenrec Echinops telfairi was determined in this study. It is an endemic African insectivore that is found specifically in Madagascar. The tenrec's back is covered with hedgehog-like spines. Unlike other spiny mammals, such as spiny mice, spiny rats, spiny dormice and porcupines, lesser hedgehog tenrecs look amazingly like true hedgehogs (Erinaceidae). However, they are distinguished morphologically from hedgehogs by the absence of a jugal bone. We determined the complete sequence of the mitochondrial genome of a lesser hedgehog tenrec and analyzed the results phylogenetically to determine the relationships between the tenrec and other insectivores (moles, shrews and hedgehogs), as well as the relationships between the tenrec and endemic African mammals, classified as Afrotheria, that have recently been shown by molecular analysis to be close relatives of the tenrec. Our data confirmed the afrotherian status of the tenrec, and no direct relation was recovered between the tenrec and the hedgehog. Comparing our data with those of others, we found that within-species variations in the mitochondrial DNA of lesser hedgehog tenrecs appear to be the largest recognized to date among mammals, apart from orangutans, which might be interesting from the view point of evolutionary history of tenrecs on Madagascar.

Efficacy of a combination of 10% imidacloprid and 1% moxidectin against Caparinia tripilis in African pygmy hedgehog (Atelerix albiventris

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Kim Kyu-Rim

2012-08-01

Full Text Available Abstract Background The efficacy and safety of a combination formulation of 10% imidacloprid + 1.0% moxidectin spot-on (Advocate® for Cats, Bayer Animal Health GmbH, Leverkusen, Germany was tested in 40 African pygmy hedgehogs (Atelerix albiventris naturally infested with Caparinia tripilis. Methods The optimal dosage level of the combination for hedgehogs was determined by assigning 20 hedgehogs into three treatment groups (0.1, 0.4 and 1.6 ml/Kg b.w., and one untreated control group of 5 hedgehogs each. Twenty naturally infested hedgehogs were then randomly assigned to either treatment or control group with 10 animals each, and the number of live mites was counted from 13 body regions on day 0, 3, 9, 16, and 30 after single treatment at the dosage level of 0.1 ml/Kg. Results Before the chemotherapy, the highest density of mite was observed in external ear canals followed by the dorsal and the lowest in the ventral regions of the body surface. The dosage level of 0.1 ml/Kg, which corresponded to the recommended dosage level for cats, containing 10 mg imidacloprid and 1 mg moxidectin was also the optimal dosage level for hedgehogs. No hedgehogs in the treatment group showed live mites from day 3 post treatment. Side effects such as ataxia, depression, nausea, and weight fluctuation were not observed during the whole period of study. Conclusions This report suggests that a combination formulation of 0.1 ml/Kg of 10% imidacloprid + 1% moxidectin spot-on for cats is also useful for the control of Caparinia tripilis infestation in hedgehogs.

Hedgehogs (Erinaceus europaeus as a Source of Ectoparasites in Urban-suburban Areas of Northwest of Iran

Directory of Open Access Journals (Sweden)

Nasser Hajipour

2015-10-01

Full Text Available Background: Hedgehogs are small, nocturnal mammals which become popular in the world and have important role in transmission of zoonotic agents. Thus, the present study aimed to survey ectoparasite infestation from April 2010 to December 2011 in urban and suburban parts of Urmia and Tabriz Cities, Northwest of Iran.Methods: A total number of 84 hedgehogs (40 females and 44 males were examined. They have been carefully inspected for ectoparasites and collected arthropods were stored in 70% ethanol solution. The identification of arthropods was carried out using morphological diagnostic keys.Results: The occurrence of ticks on hedgehogs was 23 (67.7% with Rhipicephalus turanicus in Urmia and 11 (22% as well as 1(2% with Rh. turanicus and Hyalomma anatolicum anatolicum in Tabriz, respectively. One flea species, Archaeopsylla erinacei, was found with prevalence of 19 (55.9% and 27 (54% in Urmia and Tabriz Cities, respectively. Prevalence of infestation with Rh. turanicus and A. erinacei were not different (P> 0.05 between sexes of hedgehogs in two study areas. Highest prevalence of tick and flea infestation was in June in Urmia, whereas it was observed in August in Tabriz. Both tick and flea parasitizing hedgehogs showed seasonal difference in prevalence (P< 0.05 in Urmia, but it was not detected in Tabriz (P> 0.05.Conclusion: The result showed the high occurrence of ectoparasites in hedgehog population and according to the zoonotic potential of these animals as vector of some agents further studies are needed to investigate in different parts of Iran.

Familial lecithin-cholesterol acyltransferase (LCAT) deficiency; a differential of proteinuria

OpenAIRE

Althaf, Mohammed Mahdi; Almana, Hadeel; Abdelfadiel, Ahmed; Amer, Sadiq Mohammed; Al-Hussain, Turki Omar

2015-01-01

Background: Lecithin cholesterol acyltransferase (LCAT) is an important enzyme in cholesterol metabolism that is involved in the esterification of cholesterol. A lack of this enzyme results in deranged metabolic pathways that are not completely understood, resulting in abnormal deposition of lipids in several organs. Clinically, it manifests with proteinuria, dyslipidemia and corneal opacity with progressive chronic kidney disease resulting in end-stage renal disease. Case Presentation: We he...

The gross anatomy of the male reproductive system of the European hedgehog (Erinaceus Europaeus).

Science.gov (United States)

Akbari, G; Babaei, M; Kianifard, D; Mohebi, D

2018-01-01

Hedgehogs are small spiny-coated insectivores. Due to their low body weight, calm character, and easy maintenance, they are kept as pets. It is therefore worthwhile to care about hedgehogs' health problems and to provide pet owners with information about their reproduction. Moreover, it is necessary to be familiar with their anatomy so as to satisfy the need to improve nutrition and medical care, even surgery. This study was carried out on five adult male European hedgehogs euthanased in a chloroform chamber. The European hedgehog's oval testes are invisible in inguinal region because they have no true scrotal sac. The testes are located in the craniocaudal direction with dorsolateral epididymal attachments. The vesicular glands, the European hedgehog's largest accessory sex glands, are lobulated structures containing dorsomedial and ventrolateral parts on each side. The prostate is an oval gland with right and left lobes. The paired bulbourethral glands are laid on the ischiocavernosus muscle. Histologically the vesicular, prostate gland ducts and ductus deferens as well as urethra separately were discharged in a diverticlum at the level of the pelvic urethra end. A sigmoid flexure exists in the proximal part of shaft body of the penis. There are two retractor penile muscles. In dorsal end of the penile glans, there is a small urethral process with two nail- -like, needle-shaped structures. They are on both sides of the urethral process. Furthermore, there are two intromittent sacs (Sacculus urethralis) in the ventral part of the end of the penis. (Folia Morphol 2018; 77, 1: 36-43).

Hedgehog Signaling Promotes the Proliferation and Subsequent Hair Cell Formation of Progenitor Cells in the Neonatal Mouse Cochlea

Science.gov (United States)

Chen, Yan; Lu, Xiaoling; Guo, Luo; Ni, Wenli; Zhang, Yanping; Zhao, Liping; Wu, Lingjie; Sun, Shan; Zhang, Shasha; Tang, Mingliang; Li, Wenyan; Chai, Renjie; Li, Huawei

2017-01-01

Hair cell (HC) loss is the major cause of permanent sensorineural hearing loss in mammals. Unlike lower vertebrates, mammalian cochlear HCs cannot regenerate spontaneously after damage, although the vestibular system does maintain limited HC regeneration capacity. Thus HC regeneration from the damaged sensory epithelium has been one of the main areas of research in the field of hearing restoration. Hedgehog signaling plays important roles during the embryonic development of the inner ear, and it is involved in progenitor cell proliferation and differentiation as well as the cell fate decision. In this study, we show that recombinant Sonic Hedgehog (Shh) protein effectively promotes sphere formation, proliferation, and differentiation of Lgr5+ progenitor cells isolated from the neonatal mouse cochlea. To further explore this, we determined the effect of Hedgehog signaling on cell proliferation and HC regeneration in cultured cochlear explant from transgenic R26-SmoM2 mice that constitutively activate Hedgehog signaling in the supporting cells of the cochlea. Without neomycin treatment, up-regulation of Hedgehog signaling did not significantly promote cell proliferation or new HC formation. However, after injury to the sensory epithelium by neomycin treatment, the over-activation of Hedgehog signaling led to significant supporting cell proliferation and HC regeneration in the cochlear epithelium explants. RNA sequencing and real-time PCR were used to compare the transcripts of the cochleae from control mice and R26-SmoM2 mice, and multiple genes involved in the proliferation and differentiation processes were identified. This study has important implications for the treatment of sensorineural hearing loss by manipulating the Hedgehog signaling pathway. PMID:29311816

Hedgehog Signaling Promotes the Proliferation and Subsequent Hair Cell Formation of Progenitor Cells in the Neonatal Mouse Cochlea

Directory of Open Access Journals (Sweden)

Yan Chen

2017-12-01

Full Text Available Hair cell (HC loss is the major cause of permanent sensorineural hearing loss in mammals. Unlike lower vertebrates, mammalian cochlear HCs cannot regenerate spontaneously after damage, although the vestibular system does maintain limited HC regeneration capacity. Thus HC regeneration from the damaged sensory epithelium has been one of the main areas of research in the field of hearing restoration. Hedgehog signaling plays important roles during the embryonic development of the inner ear, and it is involved in progenitor cell proliferation and differentiation as well as the cell fate decision. In this study, we show that recombinant Sonic Hedgehog (Shh protein effectively promotes sphere formation, proliferation, and differentiation of Lgr5+ progenitor cells isolated from the neonatal mouse cochlea. To further explore this, we determined the effect of Hedgehog signaling on cell proliferation and HC regeneration in cultured cochlear explant from transgenic R26-SmoM2 mice that constitutively activate Hedgehog signaling in the supporting cells of the cochlea. Without neomycin treatment, up-regulation of Hedgehog signaling did not significantly promote cell proliferation or new HC formation. However, after injury to the sensory epithelium by neomycin treatment, the over-activation of Hedgehog signaling led to significant supporting cell proliferation and HC regeneration in the cochlear epithelium explants. RNA sequencing and real-time PCR were used to compare the transcripts of the cochleae from control mice and R26-SmoM2 mice, and multiple genes involved in the proliferation and differentiation processes were identified. This study has important implications for the treatment of sensorineural hearing loss by manipulating the Hedgehog signaling pathway.

The vitamin D receptor is required for activation of cWnt and hedgehog signaling in keratinocytes.

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Lisse, Thomas S; Saini, Vaibhav; Zhao, Hengguang; Luderer, Hilary F; Gori, Francesca; Demay, Marie B

2014-10-01

Alopecia (hair loss) in vitamin D receptor (VDR)-null mice is due to absence of ligand-independent actions of the VDR that are required for initiation of postmorphogenic hair cycles. Investigations were undertaken to determine whether the VDR is required for the induction of signaling pathways that play an important role in this process. The induction of cWnt and hedgehog target genes that characterizes early anagen was found to be dramatically attenuated in VDR(-/-) mice, relative to wild-type (WT) mice. To determine whether this reflects impaired responsiveness to cWnt ligands, in vitro studies were performed in primary keratinocytes. These studies demonstrated impaired induction of cWnt target genes in response to Wnt3a in VDR(-/-) keratinocytes, relative to wild-type keratinocytes. Chromatin immunoprecipitation analyses revealed that the VDR was recruited to the regulatory regions of cWnt and hedgehog target genes in WT keratinocytes but not in VDR(-/-) or Lef1(-/-) keratinocytes. Lef1 was enriched on these same regulatory regions in WT keratinocytes but not in VDR(-/-) keratinocytes. In vivo studies were performed to determine whether activation of the hedgehog pathway could bypass the defect in cWnt signaling observed in the absence of the unliganded VDR. In WT, but not VDR(-/-), mice, hedgehog agonist treatment resulted in an induction of cWnt and hedgehog target genes and the generation of mature anagen hair follicles. Thus, these studies demonstrate that the unliganded VDR interacts with regulatory regions in the cWnt and hedgehog target genes and is required for the induction of these pathways during the postnatal hair cycle.

Fluralaner as a single dose oral treatment for Caparinia tripilis in a pygmy African hedgehog.

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Romero, Camilo; Sheinberg Waisburd, Galia; Pineda, Jocelyn; Heredia, Rafael; Yarto, Enrique; Cordero, Alberto M

2017-12-01

African pygmy hedgehogs (Atelerix albiventris) are popular pets belonging to the Erinaceidae family of spined mammals. Amongst the most common skin diseases occurring in this species is infestation caused by the mite Caparinia spp. Due to their skin anatomy and spiny coat, detection of skin lesions in these hedgehogs can be difficult. This may result in delays in seeking medical care, which may lead to secondary bacterial infection and self-inflicted trauma. Multiple therapies have been used in the treatment of this skin condition including ivermectin, amitraz, fipronil and selamectin. A drug which could be administered as a single oral dose would be advantageous to these pets and their owners. To evaluate the effect of a single oral dose (15 mg/kg) of fluralaner on Caparinia tripilis infestation in the African pygmy hedgehog. A 10-month-old African pygmy hedgehog weighing 184 g. Response to treatment was monitored by dermatological examination and superficial skin scrapings repeated at 7, 14, 21, 30, 60, 90 and 120 days following fluralaner administration. On Day 7 after treatment, adult mites were observed exhibiting normal movement. On Day 14, only dead mites were observed. No life stages of the mites were found after Day 21. A single oral dose at 15 mg/kg of fluralaner was effective within 21 days after treatment for capariniasis in this case. Further studies are required to evaluate the drug's safety and toxicology in hedgehogs, and to confirm efficacy. © 2017 ESVD and ACVD.

Involvement of an octose ketoreductase and two acyltransferases in the biosynthesis of paulomycins

Science.gov (United States)

Li, Jine; Wang, Min; Ding, Yong; Tang, Yue; Zhang, Zhiguo; Chen, Yihua

2016-02-01

C-4 hydroxyethyl branched octoses have been observed in polysaccharides of several genera of gram negative bacteria and in various antibiotics produced by gram positive bacteria. The C-4 hydroxyethyl branch was proposed to be converted from C-4 acetyl branch by an uncharacterized ketoreduction step. Paulomycins (PAUs) are glycosylated antibiotics with potent inhibitory activity against gram positive bacteria and are structurally defined by its unique C-4‧ hydroxyethyl branched paulomycose moiety. A novel aldo-keto-reductase, Pau7 was characterized as the enzyme catalyzing the stereospecific ketoreduction of 7‧-keto of PAU E (1) to give the C-4‧ hydroxyethyl branched paulomycose moiety of PAU F (2). An acyltransferase Pau6 further decorates the C-4‧ hydroxyethyl branch of paulomycose moiety of 2 by attaching various fatty acyl chains to 7‧-OH to generate diverse PAUs. In addition, another acyltransferase Pau24 was proposed to be responsible for the 13-O-acetylation of PAUs.

Human plasma lecithin-cholesterol acyltransferase

International Nuclear Information System (INIS)

Jauhiainen, M.; Stevenson, K.J.; Dolphin, P.J.

1988-01-01

Lecithin-cholesterol acyltransferase (LCAT) is a plasma enzyme which catalyzes the transacylation of the fatty acid at the sn-2 position of lecithin to cholesterol forming lysolecithin and cholesteryl ester. The substrates for and products of this reaction are present within the plasma lipoproteins upon which the enzyme acts to form the majority of cholesteryl ester in human plasma. The authors proposed a covalent catalytic mechanism of action for LCAT in which serine and histidine residues mediate lecithin cleavage and two cysteine residues cholesterol esterification. With the aid of sulfhydryl reactive trivalent organoarsenical compounds which are specific for vicinal thiols they have probed the geometry of the catalytic site. They conclude that the two catalytic cysteine residues of LCAT (Cys 31 and Cys 184 ) are vicinal with a calculated distance between their sulfur atoms of 3.50-3.62 A. The additional residue alkylated by teh bifunctional reagent is within the catalytic site and may represent a previously identified catalytic serine or histidine residue

Proliferation of murine midbrain neural stem cells depends upon an endogenous sonic hedgehog (Shh) source.

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Martínez, Constanza; Cornejo, Víctor Hugo; Lois, Pablo; Ellis, Tammy; Solis, Natalia P; Wainwright, Brandon J; Palma, Verónica

2013-01-01

The Sonic Hedgehog (Shh) pathway is responsible for critical patterning events early in development and for regulating the delicate balance between proliferation and differentiation in the developing and adult vertebrate brain. Currently, our knowledge of the potential role of Shh in regulating neural stem cells (NSC) is largely derived from analyses of the mammalian forebrain, but for dorsal midbrain development it is mostly unknown. For a detailed understanding of the role of Shh pathway for midbrain development in vivo, we took advantage of mouse embryos with cell autonomously activated Hedgehog (Hh) signaling in a conditional Patched 1 (Ptc1) mutant mouse model. This animal model shows an extensive embryonic tectal hypertrophy as a result of Hh pathway activation. In order to reveal the cellular and molecular origin of this in vivo phenotype, we established a novel culture system to evaluate neurospheres (nsps) viability, proliferation and differentiation. By recreating the three-dimensional (3-D) microenvironment we highlight the pivotal role of endogenous Shh in maintaining the stem cell potential of tectal radial glial cells (RGC) and progenitors by modulating their Ptc1 expression. We demonstrate that during late embryogenesis Shh enhances proliferation of NSC, whereas blockage of endogenous Shh signaling using cyclopamine, a potent Hh pathway inhibitor, produces the opposite effect. We propose that canonical Shh signaling plays a central role in the control of NSC behavior in the developing dorsal midbrain by acting as a niche factor by partially mediating the response of NSC to epidermal growth factor (EGF) and fibroblast growth factor (FGF) signaling. We conclude that endogenous Shh signaling is a critical mechanism regulating the proliferation of stem cell lineages in the embryonic dorsal tissue.

Topological spin-hedgehog crystals of a chiral magnet as engineered with magnetic anisotropy

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Kanazawa, N.; White, J. S.; Rønnow, H. M.; Dewhurst, C. D.; Morikawa, D.; Shibata, K.; Arima, T.; Kagawa, F.; Tsukazaki, A.; Kozuka, Y.; Ichikawa, M.; Kawasaki, M.; Tokura, Y.

2017-12-01

We report the engineering of spin-hedgehog crystals in thin films of the chiral magnet MnGe by tailoring the magnetic anisotropy. As evidenced by neutron scattering on films with different thicknesses and by varying a magnetic field, we can realize continuously deformable spin-hedgehog crystals, each of which is described as a superposition state of a different set of three spin spirals (a triple-q state). The directions of the three propagation vectors q vary systematically, gathering from the three orthogonal 〈100 〉 directions towards the film normal as the strength of the uniaxial magnetic anisotropy and/or the magnetic field applied along the film normal increase. The formation of triple-q states coincides with the onset of topological Hall signals, that are ascribed to skew scattering by an emergent magnetic field originating in the nontrivial topology of spin hedgehogs. These findings highlight how nanoengineering of chiral magnets makes possible the rational design of unique topological spin textures.

Sex, age, and tissue specific accumulation of eight metals, arsenic, and selenium in the European hedgehog (Erinaceus europaeus).

Science.gov (United States)

Rautio, Anni; Kunnasranta, Mervi; Valtonen, Anu; Ikonen, Mirva; Hyvärinen, Heikki; Holopainen, Ismo J; Kukkonen, Jussi V K

2010-11-01

Many insectivores have been shown to be sensitive to heavy metals and therefore suitable for biomonitoring purposes. In Finland, the hibernation period of the European hedgehog (Erinaceus europaeus) is long, and during hibernation the stress caused by environmental toxins may be crucial. Concentrations of cadmium (Cd), copper (Cu), iron (Fe), magnesium (Mg), manganese (Mn), molybdenum (Mo), nickel (Ni), lead (Pb), arsenic (As), and selenium (Se) were measured in a population of hedgehogs in the town of Joensuu in eastern Finland during the summers of 2004 and 2005. The analyzed tissues were kidney, liver, hair, and spine. The sampled hedgehogs (n = 65) were mainly road-killed animals. As expected, the concentrations of heavy metals were low because the hedgehogs were living in a comparatively unpolluted area. Significant increases with age were found in Cd concentrations (kidney, liver, and spine) and some essential elements (Se in spine, kidney, and liver; Mo in kidney and liver; Cu in spine; Fe in liver; and Mn in spine). Age accumulation and correlations between Se and Cd and between Mo and Cd may indicate the protective roles of Se and Mo against Cd toxicity in hedgehogs, in which Cd is already at comparatively low concentrations. Sex had no significant effect on concentrations of the elements studied. In conclusion, age is an important parameter to be taken into account when studying heavy-metal concentrations in hedgehogs and other insectivores.

Cryptosporidium erinacei n. sp. (Apicomplexa: Cryptosporidiidae) in hedgehogs

Czech Academy of Sciences Publication Activity Database

Kváč, Martin; Hofmannová, L.; Hlásková, Lenka; Květoňová, Dana; Vitovec, J.; McEvoy, J.; Sak, Bohumil

2014-01-01

Roč. 201, 1-2 (2014), s. 9-17 ISSN 0304-4017 R&D Projects: GA MŠk(CZ) LH11061 Institutional support: RVO:60077344 Keywords : Cryptosporidium erinacei * taxonomy * morphology * molecular analyses * transmission studies * Cryptosporidium hedgehog genotype Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 2.460, year: 2014

Constancy and variability in cortical structure. A study on synapses and dendritic spines in hedgehog and monkey.

Science.gov (United States)

Schüz, A; Demianenko, G P

1995-01-01

Synapses and dendritic spines were investigated in the parietal cortex of the hedgehog (Erinaceus europaeus) and the monkey (Macaca mulatta). There was no significant difference in the density of synapses between the two species (14 synapses/100 microns2 in the hedgehog, 15/100 microns2 in the monkey), neither in the size of the synaptic junctions, in the proportion of Type I and Type II synapses (8-10% were of Type II in the hedgehog, 10-14% in the monkey) nor in the proportion of perforated synapses (8% in the hedgehog, 5% in the monkey). The only striking difference at the electron microscopic level concerned the frequency of synapses in which the postsynaptic profile was deeply indented into the presynaptic terminal. Such synapses were 10 times more frequent in the monkey. Dendritic spines were investigated in Golgi-preparations. The density of spines along dendrites was similar in both species. The results are discussed with regard to connectivity in the cortex of small and large brains.

Generation of N-Acylphosphatidylethanolamine by Members of the Phospholipase A/Acyltransferase (PLA/AT) Family*

Science.gov (United States)

Uyama, Toru; Ikematsu, Natsuki; Inoue, Manami; Shinohara, Naoki; Jin, Xing-Hua; Tsuboi, Kazuhito; Tonai, Takeharu; Tokumura, Akira; Ueda, Natsuo

2012-01-01

Bioactive N-acylethanolamines (NAEs), including N-palmitoylethanolamine, N-oleoylethanolamine, and N-arachidonoylethanolamine (anandamide), are formed from membrane glycerophospholipids in animal tissues. The pathway is initiated by N-acylation of phosphatidylethanolamine to form N-acylphosphatidylethanolamine (NAPE). Despite the physiological importance of this reaction, the enzyme responsible, N-acyltransferase, remains molecularly uncharacterized. We recently demonstrated that all five members of the HRAS-like suppressor tumor family are phospholipid-metabolizing enzymes with N-acyltransferase activity and are renamed HRASLS1–5 as phospholipase A/acyltransferase (PLA/AT)-1–5. However, it was poorly understood whether these proteins were involved in the formation of NAPE in living cells. In the present studies, we first show that COS-7 cells transiently expressing recombinant PLA/AT-1, -2, -4, or -5, and HEK293 cells stably expressing PLA/AT-2 generated significant amounts of [14C]NAPE and [14C]NAE when cells were metabolically labeled with [14C]ethanolamine. Second, as analyzed by liquid chromatography-tandem mass spectrometry, the stable expression of PLA/AT-2 in cells remarkably increased endogenous levels of NAPEs and NAEs with various N-acyl species. Third, when NAPE-hydrolyzing phospholipase D was additionally expressed in PLA/AT-2-expressing cells, accumulating NAPE was efficiently converted to NAE. We also found that PLA/AT-2 was partly responsible for NAPE formation in HeLa cells that endogenously express PLA/AT-2. These results suggest that PLA/AT family proteins may produce NAPEs serving as precursors of bioactive NAEs in vivo. PMID:22825852

First report of acariasis by Caparinia tripilis in African hedgehogs, (Atelerix albiventris), in Costa Rica.

Science.gov (United States)

Moreira, Andrés; Troyo, Adriana; Calderón-Arguedas, Olger

2013-01-01

The African hedgehog is one of the newly imported exotic pets which have been observed with increasing regularity in veterinary clinics in Costa Rica. Despite their popularity, information about their diseases is scarce. Within skin diseases of hedgehogs, mange caused by Caparinia spp. is a common diagnosis in other countries. Two adult African hedgehogs, one male and one female, were brought to a private clinic in Heredia, Costa Rica, with chronic pruritic dermatitis, scabs, nearly complete loss of spines, lethargy, dehydration, and weight loss. During physical exam, deposits of dry seborrhea were taken and processed for diagnosis. Microscopic examination revealed psoroptid mites identified as Caparinia tripilis. This is the first report of the presence of Caparinia tripilis in Costa Rica and, to the authors' knowledge, the rest of Central America.

Desert hedgehog promotes ischemia-induced angiogenesis by ensuring peripheral nerve survival.

Science.gov (United States)

Renault, Marie-Ange; Chapouly, Candice; Yao, Qinyu; Larrieu-Lahargue, Frédéric; Vandierdonck, Soizic; Reynaud, Annabel; Petit, Myriam; Jaspard-Vinassa, Béatrice; Belloc, Isabelle; Traiffort, Elisabeth; Ruat, Martial; Duplàa, Cécile; Couffinhal, Thierry; Desgranges, Claude; Gadeau, Alain-Pierre

2013-03-01

Blood vessel growth and patterning have been shown to be regulated by nerve-derived signals. Desert hedgehog (Dhh), one of the Hedgehog family members, is expressed by Schwann cells of peripheral nerves. The purpose of this study was to investigate the contribution of Dhh to angiogenesis in the setting of ischemia. We induced hindlimb ischemia in wild-type and Dhh(-/-) mice. First, we found that limb perfusion is significantly impaired in the absence of Dhh. This effect is associated with a significant decrease in capillary and artery density in Dhh(-/-). By using mice in which the Hedgehog signaling pathway effector Smoothened was specifically invalidated in endothelial cells, we demonstrated that Dhh does not promote angiogenesis by a direct activation of endothelial cells. On the contrary, we found that Dhh promotes peripheral nerve survival in the ischemic muscle and, by doing so, maintains the pool of nerve-derived proangiogenic factors. Consistently, we found that denervation of the leg, immediately after the onset of ischemia, severely impairs ischemia-induced angiogenesis and decreases expression of vascular endothelial growth factor A, angiopoietin 1, and neurotrophin 3 in the ischemic muscle. This study demonstrates the crucial roles of nerves and factors regulating nerve physiology in the setting of ischemia-induced angiogenesis.

Structural basis of SUFU–GLI interaction in human Hedgehog signalling regulation

International Nuclear Information System (INIS)

Cherry, Amy L.; Finta, Csaba; Karlström, Mikael; Jin, Qianren; Schwend, Thomas; Astorga-Wells, Juan; Zubarev, Roman A.; Del Campo, Mark; Criswell, Angela R.; Sanctis, Daniele de; Jovine, Luca; Toftgård, Rune

2013-01-01

Crystal and small-angle X-ray scattering structures of full-length human SUFU alone and in complex with the conserved SYGHL motif from GLI transcription factors show major conformational changes associated with binding and reveal an intrinsically disordered region crucial for pathway activation. Hedgehog signalling plays a fundamental role in the control of metazoan development, cell proliferation and differentiation, as highlighted by the fact that its deregulation is associated with the development of many human tumours. SUFU is an essential intracellular negative regulator of mammalian Hedgehog signalling and acts by binding and modulating the activity of GLI transcription factors. Despite its central importance, little is known about SUFU regulation and the nature of SUFU–GLI interaction. Here, the crystal and small-angle X-ray scattering structures of full-length human SUFU and its complex with the key SYGHL motif conserved in all GLIs are reported. It is demonstrated that GLI binding is associated with major conformational changes in SUFU, including an intrinsically disordered loop that is also crucial for pathway activation. These findings reveal the structure of the SUFU–GLI interface and suggest a mechanism for an essential regulatory step in Hedgehog signalling, offering possibilities for the development of novel pathway modulators and therapeutics

Structural basis of SUFU–GLI interaction in human Hedgehog signalling regulation

Energy Technology Data Exchange (ETDEWEB)

Cherry, Amy L.; Finta, Csaba; Karlström, Mikael; Jin, Qianren; Schwend, Thomas [Karolinska Institutet, Novum, Hälsovägen 7, SE-141 83 Huddinge (Sweden); Astorga-Wells, Juan [Karolinska Institutet, Scheeles väg 2, SE-171 77 Stockholm (Sweden); Biomotif AB, Enhagsvägen 7, SE-182 12 Danderyd (Sweden); Zubarev, Roman A. [Karolinska Institutet, Scheeles väg 2, SE-171 77 Stockholm (Sweden); Del Campo, Mark; Criswell, Angela R. [Rigaku Americas Corporation, 9009 New Trails Drive, The Woodlands, TX 77381 (United States); Sanctis, Daniele de [European Synchrotron Radiation Facility, 6 Rue Jules Horowitz, 38043 Grenoble (France); Jovine, Luca, E-mail: luca.jovine@ki.se; Toftgård, Rune, E-mail: luca.jovine@ki.se [Karolinska Institutet, Novum, Hälsovägen 7, SE-141 83 Huddinge (Sweden)

2013-12-01

Crystal and small-angle X-ray scattering structures of full-length human SUFU alone and in complex with the conserved SYGHL motif from GLI transcription factors show major conformational changes associated with binding and reveal an intrinsically disordered region crucial for pathway activation. Hedgehog signalling plays a fundamental role in the control of metazoan development, cell proliferation and differentiation, as highlighted by the fact that its deregulation is associated with the development of many human tumours. SUFU is an essential intracellular negative regulator of mammalian Hedgehog signalling and acts by binding and modulating the activity of GLI transcription factors. Despite its central importance, little is known about SUFU regulation and the nature of SUFU–GLI interaction. Here, the crystal and small-angle X-ray scattering structures of full-length human SUFU and its complex with the key SYGHL motif conserved in all GLIs are reported. It is demonstrated that GLI binding is associated with major conformational changes in SUFU, including an intrinsically disordered loop that is also crucial for pathway activation. These findings reveal the structure of the SUFU–GLI interface and suggest a mechanism for an essential regulatory step in Hedgehog signalling, offering possibilities for the development of novel pathway modulators and therapeutics.

Zebrafish genetics gets the Scube on Hedgehog secretion.

Science.gov (United States)

Ingham, Philip W

2012-11-15

Inspired by a zebrafish mutation, two recent studies by Creanga and colleagues (pp. 1312-1325) and Tukachinsky and colleagues have shed new light on the way in which lipidated Hedgehog proteins are secreted and released from expressing cells, suggesting a model for the sequential action of the Disp and Scube2 proteins in this process.

Canonical hedgehog signaling augments tumor angiogenesis by induction of VEGF-A in stromal perivascular cells

Science.gov (United States)

Chen, Weiwei; Tang, Tracy; Eastham-Anderson, Jeff; Dunlap, Debra; Alicke, Bruno; Nannini, Michelle; Gould, Stephen; Yauch, Robert; Modrusan, Zora; DuPree, Kelly J.; Darbonne, Walter C.; Plowman, Greg; de Sauvage, Frederic J.; Callahan, Christopher A.

2011-01-01

Hedgehog (Hh) signaling is critical to the patterning and development of a variety of organ systems, and both ligand-dependent and ligand-independent Hh pathway activation are known to promote tumorigenesis. Recent studies have shown that in tumors promoted by Hh ligands, activation occurs within the stromal microenvironment. Testing whether ligand-driven Hh signaling promotes tumor angiogenesis, we found that Hh antagonism reduced the vascular density of Hh-producing LS180 and SW480 xenografts. In addition, ectopic expression of sonic hedgehog in low-Hh–expressing DLD-1 xenografts increased tumor vascular density, augmented angiogenesis, and was associated with canonical Hh signaling within perivascular tumor stromal cells. To better understand the molecular mechanisms underlying Hh-mediated tumor angiogenesis, we established an Hh-sensitive angiogenesis coculture assay and found that fibroblast cell lines derived from a variety of human tissues were Hh responsive and promoted angiogenesis in vitro through a secreted paracrine signal(s). Affymetrix array analyses of cultured fibroblasts identified VEGF-A, hepatocyte growth factor, and PDGF-C as candidate secreted proangiogenic factors induced by Hh stimulation. Expression studies of xenografts and angiogenesis assays using combinations of Hh and VEGF-A inhibitors showed that it is primarily Hh-induced VEGF-A that promotes angiogenesis in vitro and augments tumor-derived VEGF to promote angiogenesis in vivo. PMID:21597001

Black-holes-hedgehogs in the false vacuum and a new physics beyond the Standard Model

Science.gov (United States)

Das, C. R.; Laperashvili, L. V.; Sidharth, B. G.; Nielsen, H. B.

2017-12-01

In the present talk, we consider the existence of the two degenerate universal vacua: a) the first Electroweak vacuum at v = 246 GeV - “true vacuum”, and b) the second Planck scale “false vacuum” at v 2 ∼ 1018 GeV. In these vacua, we investigated the different topological defects. The main aim of this paper is an investigation of the hedgehog’s configurations as defects of the false vacuum. In the framework of the f(R) gravity, suggested by authors in their Gravi-Weak Unification model, we obtained a black hole solution, which corresponds to a “hedgehog” - global monopole, “swallowed” by a black-hole with mass ∼ 1019 GeV. These black-holes form a lattice-like structure of the vacuum at the Planck scale. Considering the results of the hedgehog lattice theory in the framework of the SU(2) Yang-Mills gauge-invariant theory with hedgehogs in the Wilson loops, we have used the critical value of temperature for the hedgehog’s confinement phase. This result gave us the possibility to conclude that there exist triplet Higgs fields which can contribute to the SM at the energy scale ≃ 104 ∼ 105 GeV. Showing a new physics at the scale 10÷100 TeV, these triplet Higgs particles can provide the stability of the EW-vacuum of the SM.

Dynamic impact testing of hedgehog spines using a dual-arm crash pendulum.

Science.gov (United States)

Swift, Nathan B; Hsiung, Bor-Kai; Kennedy, Emily B; Tan, Kwek-Tze

2016-08-01

Hedgehog spines are a potential model for impact resistant structures and material. While previous studies have examined static mechanical properties of individual spines, actual collision tests on spines analogous to those observed in the wild have not previously been investigated. In this study, samples of roughly 130 keratin spines were mounted vertically in thin substrates to mimic the natural spine layout on hedgehogs. A weighted crash pendulum was employed to induce and measure the effects of repeated collisions against samples, with the aim to evaluate the influence of various parameters including humidity effect, impact energy, and substrate hardness. Results reveal that softer samples-due to humidity conditioning and/or substrate material used-exhibit greater durability over multiple impacts, while the more rigid samples exhibit greater energy absorption performance at the expense of durability. This trend is exaggerated during high-energy collisions. Comparison of the results to baseline tests with industry standard impact absorbing foam, wherein the spines exhibit similar energy absorption, verifies the dynamic impact absorption capabilities of hedgehog spines and their candidacy as a structural model for engineered impact technology. Copyright © 2016 Elsevier Ltd. All rights reserved.

Measurement of dihydroxyacetone-phosphate acyltransferase (DHAPAT) in chorionic villous samples, blood cells and cultured cells

NARCIS (Netherlands)

Wanders, R. J.; Ofman, R.; Romeijn, G. J.; Schutgens, R. B.; Mooijer, P. A.; Dekker, C.; van den Bosch, H.

1995-01-01

Dihydroxyacetone-phosphate acyltransferase (DHAPAT) is a peroxisomal enzyme catalysing the first step in ether-phospholipid biosynthesis. DHAPAT is deficient in cells from patients suffering from a variety of peroxisomal disorders. Accurate measurement of the activity of this enzyme is of great

Comparison of two systemic antifungal agents, itraconazole and terbinafine, for the treatment of dermatophytosis in European hedgehogs (Erinaceus europaeus).

Science.gov (United States)

Bexton, Steve; Nelson, Helen

2016-12-01

Dermatophytosis caused by Trichophyton erinacei is a common scaling and crusting skin disease affecting European hedgehogs (Erinaceus europaeus) admitted to wildlife rescue centres. The application of topical therapy can be challenging because wild hedgehogs are subject to stress and often roll into a ball when handled. Systemic antifungal therapy is more convenient but has not been evaluated in this species. To compare the efficacy of oral itraconazole versus oral terbinafine for the treatment of dermatophytosis affecting hedgehogs. A treatment trial was undertaken in a wildlife hospital involving 165 hedgehogs with naturally occurring dermatophytosis. Animals were randomly divided into two groups and treated with either itraconazole or terbinafine orally for 28 days. The therapeutic efficacy was evaluated after 14 and 28 days by mycological culture and clinical dermatological lesion scores. Both drugs were well tolerated and clinically effective. After 14 and 28 days of treatment, the respective mycological cure rate was 36.6% and 65.9% for the itraconazole-treated group and 92.8% and 98.8% for the terbinafine-treated group. Itraconazole and terbinafine were both effective for the treatment of dermatophytosis affecting hedgehogs; however, terbinafine was more effective. © 2016 ESVD and ACVD.

The long noncoding RNA TUG1 acts as a competing endogenous RNA to regulate the Hedgehog pathway by targeting miR-132 in hepatocellular carcinoma.

Science.gov (United States)

Li, Jingjing; Zhang, Qinghui; Fan, Xiaoming; Mo, Wenhui; Dai, Weiqi; Feng, Jiao; Wu, Liwei; Liu, Tong; Li, Sainan; Xu, Shizan; Wang, Wenwen; Lu, Xiya; Yu, Qiang; Chen, Kan; Xia, Yujing; Lu, Jie; Zhou, Yingqun; Xu, Ling; Guo, Chuanyong

2017-09-12

Emerging evidence shows that the Hedgehog pathway and the long noncoding RNA TUG1 play pivotal roles in cell proliferation, migration, and invasion in tumors. However, the mechanism underlying the effect of TUG1 and the Hedgehog pathway in hepatoma remains undefined. In the present study, we showed that the expression of TUG1 was negatively correlated with that of microRNA (miR)-132, and depletion of TUG1 inhibited the activation of the Hedgehog pathway in vitro and in vivo . We showed that TUG1 functions as a competing endogenous (ceRNA) by competing with miR-132 for binding to the sonic hedgehog protein in HCC, thereby suppressing the activation of Hedgehog signaling and its tumorigenic effect. These data indicate that targeting the TUG1-miR132-Hedgehog network could be a new strategy for the treatment of HCC.

Reproductive characteristics of the african pygmy hedgehog, atelerix albiventris.

Science.gov (United States)

Bedford, J M; Mock, O B; Nagdas, S K; Winfrey, V P; Olson, G E

2000-09-01

To obtain further perspective on reproduction and particularly gamete function among so-called primitive mammals presently grouped in the Order Insectivora, we have examined the African hedgehog, Atelerix albiventris, in light of unusual features reported in shrews and moles. Atelerix proves to share many but not all of the characteristics seen in these other insectivores. The penis of Atelerix has a 'snail-like' form, but lacks the surface spines common in insectivores and a number of other mammals. Hedgehog spermatozoa display an eccentric insertion of the tail on the sperm head, and they manifest the barbs on the perforatorium that, in shrews, probably effect the initial binding of the sperm head to the zona pellucida. As a possible correlate, the structural matrix of the hedgehog acrosome comprises only two main components, as judged by immunoblotting, rather than the complex of peptides seen in the matrix of some higher mammals. The Fallopian tube of Atelerix is relatively simple; it displays only minor differences in width and in the arborized epithelium between the isthmus and ampulla, and shows no evidence of the unusual sperm crypts that characterize the isthmus or ampulla, depending on the species, in shrews and moles. In common with other insectivores, Atelerix appears to be an induced ovulator, as judged by the ovulation of some 6-8 eggs by about 23 h after injection of hCG. The dense cumulus oophorus appeared to have little matrix, in keeping with the modest dimensions of the tubal ampulla and, while it was not quite as discrete as that of soricids, it did show the same insensitivity to 0.5% (w/v) ovine or bovine hyaluronidase.

The anatomy and histology of the atrioventricular conducting system in the hedgehog (Hemiechinus auritus) heart

OpenAIRE

NABIPOUR, Abolghasem

2014-01-01

This study examined the atrioventricular conducting system in 4 adult male hedgehogs (Hemiechinus auritus). The histological structure of these components was studied using routine histological methods. The AVN was located at the lower and anterior part of the interatrial septum, near the root of the aorta. It was almost oval and consisted of twisted cells. Internodal pathways in the hedgehog heart were not observed, but there were numerous purkinje-like fibers within the myocardium of the at...

Basal cell carcinoma pathogenesis and therapy involving hedgehog signaling and beyond.

Science.gov (United States)

Bakshi, Anshika; Chaudhary, Sandeep C; Rana, Mehtab; Elmets, Craig A; Athar, Mohammad

2017-12-01

Basal cell carcinoma (BCC) of the skin is driven by aberrant hedgehog signaling. Thus blocking this signaling pathway by small molecules such as vismodegib inhibits tumor growth. Primary cilium in the epidermal cells plays an integral role in the processing of hedgehog signaling-related proteins. Recent genomic studies point to the involvement of additional genetic mutations that might be associated with the development of BCCs, suggesting significance of other signaling pathways, such as WNT, NOTCH, mTOR, and Hippo, aside from hedgehog in the pathogenesis of this human neoplasm. Some of these pathways could be regulated by noncoding microRNA. Altered microRNA expression profile is recognized with the progression of these lesions. Stopping treatment with Smoothened (SMO) inhibitors often leads to tumor reoccurrence in the patients with basal cell nevus syndrome, who develop 10-100 of BCCs. In addition, the initial effectiveness of these SMO inhibitors is impaired due to the onset of mutations in the drug-binding domain of SMO. These data point to a need to develop strategies to overcome tumor recurrence and resistance and to enhance efficacy by developing novel single agent-based or multiple agents-based combinatorial approaches. Immunotherapy and photodynamic therapy could be additional successful approaches particularly if developed in combination with chemotherapy for inoperable and metastatic BCCs. © 2017 Wiley Periodicals, Inc.

Hedgehog Signalling in the Embryonic Mouse Thymus

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Alessandro Barbarulo

2016-07-01

Full Text Available T cells develop in the thymus, which provides an essential environment for T cell fate specification, and for the differentiation of multipotent progenitor cells into major histocompatibility complex (MHC-restricted, non-autoreactive T cells. Here we review the role of the Hedgehog signalling pathway in T cell development, thymic epithelial cell (TEC development, and thymocyte–TEC cross-talk in the embryonic mouse thymus during the last week of gestation.

Indian Hedgehog Suppresses a Stromal Cell–Driven Intestinal Immune Response

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B. Florien Westendorp

2018-01-01

Conclusions: We show that epithelium-derived Indian Hedgehog signals exclusively to fibroblasts in the intestine. Loss of Ihh leads to a rapid immune response with up-regulation of fibroblast-derived CXCL12, and migration of immune cells into the lamina propria.

Morpholoical Study of the Brandt’s Hedgehog, Paraechinus hypomelas (Eulipotyphla, Erinaceidae, Tongue

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Goodarzi N.

2016-10-01

Full Text Available The morphology and histological structure of two adult Brandt’s hedgehog, Paraechinus hypomelas, (Brandt, 1836 tongue were examined by light and scanning electron microscopy. On the dorsal surface of the tongue, three types of papillae were observed: filiform, fungiform and vallate papillae. Apex and corpus of the tongue as well as the lateral surface of the corpus were covered with numerous filiform papillae with bifurcated tip, while the epithelium lining the ventral lingual surface was free from papillae. Discoid shape fungiform papillae were scattered over the entire surface of the lingual apex, corpus and lateral surface uniformly between the filiform ones without regional variation in number and size. Three elliptical or oval vallate papillae in an inverted triangle form were found on the root of the tongue. Each papilla had a lobulated and very irregular dorsal surface. Both fungiform and vallate papillae contain taste buds. The foliate papillae was absent. Overall, the present findings reveal that despite some similarities, the lingual papillae of the Brandt’s hedgehog as an omnivore animal has spices-specific characteristics compare to the Erinaceous auritus as an insectivore species. This finding provides a set of basic data about the morphology of tongue and its lingual papillae in Brandt’s hedgehog.

Foxf genes integrate tbx5 and hedgehog pathways in the second heart field for cardiac septation.

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Andrew D Hoffmann

2014-10-01

Full Text Available The Second Heart Field (SHF has been implicated in several forms of congenital heart disease (CHD, including atrioventricular septal defects (AVSDs. Identifying the SHF gene regulatory networks required for atrioventricular septation is therefore an essential goal for understanding the molecular basis of AVSDs. We defined a SHF Hedgehog-dependent gene regulatory network using whole genome transcriptional profiling and GLI-chromatin interaction studies. The Forkhead box transcription factors Foxf1a and Foxf2 were identified as SHF Hedgehog targets. Compound haploinsufficiency for Foxf1a and Foxf2 caused atrioventricular septal defects, demonstrating the biological relevance of this regulatory network. We identified a Foxf1a cis-regulatory element that bound the Hedgehog transcriptional regulators GLI1 and GLI3 and the T-box transcription factor TBX5 in vivo. GLI1 and TBX5 synergistically activated transcription from this cis-regulatory element in vitro. This enhancer drove reproducible expression in vivo in the posterior SHF, the only region where Gli1 and Tbx5 expression overlaps. Our findings implicate Foxf genes in atrioventricular septation, describe the molecular underpinnings of the genetic interaction between Hedgehog signaling and Tbx5, and establish a molecular model for the selection of the SHF gene regulatory network for cardiac septation.

Hedgehog Signaling and Maintenance of Homeostasis in the Intestinal Epithelium

NARCIS (Netherlands)

Büller, Nikè V. J. A.; Rosekrans, Sanne L.; Westerlund, Jessica; van den Brink, Gijs R.

2012-01-01

Homeostasis of the rapidly renewing intestinal epithelium depends on a balance between cell proliferation and loss. Indian hedgehog (Ihh) acts as a negative feedback signal in this dynamic equilibrium. We discuss recent evidence that Ihh may be one of the key epithelial signals that indicates

Inhibition of ghrelin O-acyltransferase attenuates food deprivation-induced increases in ingestive behavior.

Science.gov (United States)

Teubner, Brett J W; Garretson, John T; Hwang, Yousang; Cole, Philip A; Bartness, Timothy J

2013-04-01

Ghrelin is an orexigenic hormone produced by the stomach in direct proportion to the time since the last meal and has therefore been called a 'hunger signal'. The octanoylation of ghrelin is critical for its orexigenic functions and is dependent upon ghrelin O-acyltransferase (GOAT) catalyzation. The GOAT inhibitor, GO-CoA-Tat, decreases the circulating concentrations of octanoylated ghrelin and attenuates weight gain on a high fat diet in mice. Unlike rats and mice, Siberian hamsters and humans do not increase food intake after food deprivation, but increase food hoarding after food deprivation. In Siberian hamsters, exogenous ghrelin increases ingestive behaviors similarly to 48-56 h food deprivation. Therefore, we tested the necessity of increased ghrelin in food-deprived Siberian hamsters to stimulate ingestive behaviors. To do so we used our simulated natural housing system that allows hamsters to forage for and hoard food. Animals were given an injection of GO-CoA-Tat (i.p., 11 μmol/kg) every 6h because that is the duration of its effective inhibition of octanoylated ghrelin concentrations during a 48 h food deprivation. We found that GO-CoA-Tat attenuated food foraging (0-1h), food intake (0-1 and 2-4h), and food hoarding (0-1h and 2 and 3 days) post-refeeding compared with saline treated animals. This suggests that increased octanoylated ghrelin concentrations play a role in the food deprivation-induced increases in ingestive behavior. Therefore, ghrelin is a critical aspect of the multi-faceted mechanisms that stimulate ingestive behaviors, and might be a critical point for a successful clinical intervention scheme in humans. Copyright © 2013 Elsevier Inc. All rights reserved.

Learning to Play: A "Hedgehog Concept" for Physical Education

Science.gov (United States)

Johnson, Tyler

2014-01-01

What is physical education and why does it exist? Despite its relatively long and storied history, consensus about the main purpose of physical education remains minimal. This article explores three questions, developed by Jim Collins in his best-selling book Good to Great, to help organizations identify a hedgehog concept, or primary reason for…

Hedgehog Signaling Inhibitors as Anti-Cancer Agents in Osteosarcoma

International Nuclear Information System (INIS)

Ram Kumar, Ram Mohan; Fuchs, Bruno

2015-01-01

Osteosarcoma is a rare type of cancer associated with a poor clinical outcome. Even though the pathologic characteristics of OS are well established, much remains to be understood, particularly at the molecular signaling level. The molecular mechanisms of osteosarcoma progression and metastases have not yet been fully elucidated and several evolutionary signaling pathways have been found to be linked with osteosarcoma pathogenesis, especially the hedgehog signaling (Hh) pathway. The present review will outline the importance and targeting the hedgehog signaling (Hh) pathway in osteosarcoma tumor biology. Available data also suggest that aberrant Hh signaling has pro-migratory effects and leads to the development of osteoblastic osteosarcoma. Activation of Hh signaling has been observed in osteosarcoma cell lines and also in primary human osteosarcoma specimens. Emerging data suggests that interference with Hh signal transduction by inhibitors may reduce osteosarcoma cell proliferation and tumor growth thereby preventing osteosarcomagenesis. From this perspective, we outline the current state of Hh pathway inhibitors in osteosarcoma. In summary, targeting Hh signaling by inhibitors promise to increase the efficacy of osteosarcoma treatment and improve patient outcome

Lecithin:Retinol Acyltransferase: A Key Enzyme Involved in the Retinoid (visual) Cycle

OpenAIRE

Sears, Avery E.; Palczewski, Krzysztof

2016-01-01

Lecithin:retinol acyltransferase (LRAT) catalyzes the acyl transfer from the sn-1 position of phosphatidylcholine (PC) to all-trans-retinol, creating fatty acid retinyl esters (palmitoyl, stearoyl, and some unsaturated derivatives). In the eye, these retinyl esters are substrates for the 65 kDa retinoid isomerase (RPE65). LRAT is well characterized biochemically, and recent structural data from closely related family members of the NlpC/P60 superfamily and a chimeric protein have established ...

Epigenetic regulation of the Hedgehog and Wnt pathways in cancer

NARCIS (Netherlands)

Wils, Leon J.; Bijlsma, Maarten F.

2018-01-01

The Hedgehog (Hh) and wingless-Int1 (Wnt) pathways are important for tissue patterning in the developing embryo. In adult tissue, both pathways are typically dormant but are activated under certain conditions such as tissue damage. Aberrant activation of these pathways by mutations in key pathway

Bmi1 is required for hedgehog pathway-driven medulloblastoma expansion

NARCIS (Netherlands)

Michael, Lowell Evan; Westerman, Bart A.; Ermilov, Alexandre N.; Wang, Aiqin; Ferris, Jennifer; Liu, Jianhong; Blom, Marleen; Ellison, David W.; van Lohuizen, Maarten; Dlugosz, Andrzej A.

2008-01-01

Inappropriate Hedgehog (Hh) signaling underlies development of a subset of medulloblastomas, and tumors with elevated HH signaling activity express the stem cell self-renewal gene BMI1. To test whether Bmi1 is required for Hh-driven medulloblastoma development, we varied Bmi1 gene dosage in

Impaired Hedgehog signalling-induced endothelial dysfunction is sufficient to induce neuropathy: implication in diabetes.

Science.gov (United States)

Chapouly, Candice; Yao, Qinyu; Vandierdonck, Soizic; Larrieu-Lahargue, Frederic; Mariani, John N; Gadeau, Alain-Pierre; Renault, Marie-Ange

2016-02-01

Microangiopathy, i.e. endothelial dysfunction, has long been suggested to contribute to the development of diabetic neuropathy, although this has never been fully verified. In the present paper, we have identified the role of Hedgehog (Hh) signalling in endoneurial microvessel integrity and evaluated the impact of impaired Hh signalling in endothelial cells (ECs) on nerve function. By using Desert Hedgehog (Dhh)-deficient mice, we have revealed, that in the absence of Dhh, endoneurial capillaries are abnormally dense and permeable. Furthermore, Smoothened (Smo) conditional KO mice clarified that this increased vessel permeability is specifically due to impaired Hh signalling in ECs and is associated with a down-regulation of Claudin5 (Cldn5). Moreover, impairment of Hh signalling in ECs was sufficient to induce hypoalgesia and neuropathic pain. Finally in Lepr(db/db) type 2 diabetic mice, the loss of Dhh expression observed in the nerve was shown to be associated with increased endoneurial capillary permeability and decreased Cldn5 expression. Conversely, systemic administration of the Smo agonist SAG increased Cldn5 expression, decreased endoneurial capillary permeability, and restored thermal algesia to diabetic mice, demonstrating that loss of Dhh expression is crucial in the development of diabetic neuropathy. The present work demonstrates the critical role of Dhh in maintaining blood nerve barrier integrity and demonstrates for the first time that endothelial dysfunction is sufficient to induce neuropathy. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2015. For permissions please email: journals.permissions@oup.com.

Survivin as a therapeutic target in Sonic hedgehog-driven medulloblastoma.

Science.gov (United States)

Brun, S N; Markant, S L; Esparza, L A; Garcia, G; Terry, D; Huang, J-M; Pavlyukov, M S; Li, X-N; Grant, G A; Crawford, J R; Levy, M L; Conway, E M; Smith, L H; Nakano, I; Berezov, A; Greene, M I; Wang, Q; Wechsler-Reya, R J

2015-07-01

Medulloblastoma (MB) is a highly malignant brain tumor that occurs primarily in children. Although surgery, radiation and high-dose chemotherapy have led to increased survival, many MB patients still die from their disease, and patients who survive suffer severe long-term side effects as a consequence of treatment. Thus, more effective and less toxic therapies for MB are critically important. Development of such therapies depends in part on identification of genes that are necessary for growth and survival of tumor cells. Survivin is an inhibitor of apoptosis protein that regulates cell cycle progression and resistance to apoptosis, is frequently expressed in human MB and when expressed at high levels predicts poor clinical outcome. Therefore, we hypothesized that Survivin may have a critical role in growth and survival of MB cells and that targeting it may enhance MB therapy. Here we show that Survivin is overexpressed in tumors from patched (Ptch) mutant mice, a model of Sonic hedgehog (SHH)-driven MB. Genetic deletion of survivin in Ptch mutant tumor cells significantly inhibits proliferation and causes cell cycle arrest. Treatment with small-molecule antagonists of Survivin impairs proliferation and survival of both murine and human MB cells. Finally, Survivin antagonists impede growth of MB cells in vivo. These studies highlight the importance of Survivin in SHH-driven MB, and suggest that it may represent a novel therapeutic target in patients with this disease.

Deficiency of acyl-CoA: Dihydroxyacetone phosphate acyltransferase in patients with Zellweger (cerebro-hepato-renal) syndrome

NARCIS (Netherlands)

Bosch, H. van den; Schutgens, R.B.H.; Romeyn, G.J.; Wanders, R.J.A.; Schrakamp, G.; Heymans, H.S.A.

1984-01-01

We have recently reported on plasmalogen deficiency in tissues and fibroblasts from patients with Zellweger syndrome. In this paper we have analyzed the activity of the first enzyme in the pathway leading to plasmalogen biosynthesis, i.e. acyl-CoA: dihydroxyacetone phosphate acyltransferase in

Equine cryptosporidial infection associated with Cryptosporidium hedgehog genotype in Algeria

Czech Academy of Sciences Publication Activity Database

Laatamna, A.E.; Wágnerová, P.; Sak, Bohumil; Květoňová, Dana; Aissi, M.; Rost, M.; Kváč, Martin

2013-01-01

Roč. 197, 1-2 (2013), s. 350-353 ISSN 0304-4017 Grant - others:GAJU(CZ) 022/2010/Z; GAJU(CZ) 011/2013/Z Institutional support: RVO:60077344 Keywords : horses * Cryptosporidium hedgehog genotype * PCR * SSU * GP60 Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.545, year: 2013

MMTV-Wnt1 and -DeltaN89beta-catenin induce canonical signaling in distinct progenitors and differentially activate Hedgehog signaling within mammary tumors.

Directory of Open Access Journals (Sweden)

Brigitte Teissedre

Full Text Available Canonical Wnt/beta-catenin signaling regulates stem/progenitor cells and, when perturbed, induces many human cancers. A significant proportion of human breast cancer is associated with loss of secreted Wnt antagonists and mice expressing MMTV-Wnt1 and MMTV-DeltaN89beta-catenin develop mammary adenocarcinomas. Many studies have assumed these mouse models of breast cancer to be equivalent. Here we show that MMTV-Wnt1 and MMTV-DeltaN89beta-catenin transgenes induce tumors with different phenotypes. Using axin2/conductin reporter genes we show that MMTV-Wnt1 and MMTV-DeltaN89beta-catenin activate canonical Wnt signaling within distinct cell-types. DeltaN89beta-catenin activated signaling within a luminal subpopulation scattered along ducts that exhibited a K18(+ER(-PR(-CD24(highCD49f(low profile and progenitor properties. In contrast, MMTV-Wnt1 induced canonical signaling in K14(+ basal cells with CD24/CD49f profiles characteristic of two distinct stem/progenitor cell-types. MMTV-Wnt1 produced additional profound effects on multiple cell-types that correlated with focal activation of the Hedgehog pathway. We document that large melanocytic nevi are a hitherto unreported hallmark of early hyperplastic Wnt1 glands. These nevi formed along the primary mammary ducts and were associated with Hedgehog pathway activity within a subset of melanocytes and surrounding stroma. Hh pathway activity also occurred within tumor-associated stromal and K14(+/p63(+ subpopulations in a manner correlated with Wnt1 tumor onset. These data show MMTV-Wnt1 and MMTV-DeltaN89beta-catenin induce canonical signaling in distinct progenitors and that Hedgehog pathway activation is linked to melanocytic nevi and mammary tumor onset arising from excess Wnt1 ligand. They further suggest that Hedgehog pathway activation maybe a critical component and useful indicator of breast tumors arising from unopposed Wnt1 ligand.

Dichotomy in Hedgehog Signaling between Human Healthy Vessel and Atherosclerotic Plaques

NARCIS (Netherlands)

Queiroz, Karla C. S.; Bijlsma, Maarten F.; Tio, René A.; Zeebregts, Clark J.; Dunaeva, Marina; Ferreira, Carmen V.; Fuhler, Gwenny M.; Kuipers, Ernst J.; Alves, Maria M.; Rezaee, Farhad; Spek, C. Arnold; Peppelenbosch, Maikel P.

2012-01-01

The major cause for plaque instability in atherosclerotic disease is neoangiogenic revascularization, but the factors controlling this process remain only partly understood. Hedgehog (HH) is a morphogen with important functions in revascularization, but its function in human healthy vessel biology

Indian hedgehog mutations causing brachydactyly type A1 impair Hedgehog signal transduction at multiple levels

Science.gov (United States)

Ma, Gang; Yu, Jiang; Xiao, Yue; Chan, Danny; Gao, Bo; Hu, Jianxin; He, Yongxing; Guo, Shengzhen; Zhou, Jian; Zhang, Lingling; Gao, Linghan; Zhang, Wenjuan; Kang, Yan; Cheah, Kathryn SE; Feng, Guoyin; Guo, Xizhi; Wang, Yujiong; Zhou, Cong-zhao; He, Lin

2011-01-01

Brachydactyly type A1 (BDA1), the first recorded Mendelian autosomal dominant disorder in humans, is characterized by a shortening or absence of the middle phalanges. Heterozygous missense mutations in the Indian Hedgehog (IHH) gene have been identified as a cause of BDA1; however, the biochemical consequences of these mutations are unclear. In this paper, we analyzed three BDA1 mutations (E95K, D100E, and E131K) in the N-terminal fragment of Indian Hedgehog (IhhN). Structural analysis showed that the E95K mutation changes a negatively charged area to a positively charged area in a calcium-binding groove, and that the D100E mutation changes the local tertiary structure. Furthermore, we showed that the E95K and D100E mutations led to a temperature-sensitive and calcium-dependent instability of IhhN, which might contribute to an enhanced intracellular degradation of the mutant proteins via the lysosome. Notably, all three mutations affected Hh binding to the receptor Patched1 (PTC1), reducing its capacity to induce cellular differentiation. We propose that these are common features of the mutations that cause BDA1, affecting the Hh tertiary structure, intracellular fate, binding to the receptor/partners, and binding to extracellular components. The combination of these features alters signaling capacity and range, but the impact is likely to be variable and mutation-dependent. The potential variation in the signaling range is characterized by an enhanced interaction with heparan sulfate for IHH with the E95K mutation, but not the E131K mutation. Taken together, our results suggest that these IHH mutations affect Hh signaling at multiple levels, causing abnormal bone development and abnormal digit formation. PMID:21537345

Castor diacylglycerol acyltransferase type1(DGAT1)displays greater activity with diricinolein than Arabidopsis DGAT1

Science.gov (United States)

Castor oil contains the hydroxy fatty acid ricinoleate as a major (90%) component. The diacylglycerol acyltransferase (DGAT) carries out the final reaction step in the biosynthesis of triacylglycerol, the principal constituent of seed oil, and has been considered to be the step that controls the oil...

Discovery and characterization of inhibitors of human palmitoyl acyltransferases.

Science.gov (United States)

Ducker, Charles E; Griffel, Lindsay K; Smith, Ryan A; Keller, Staci N; Zhuang, Yan; Xia, Zuping; Diller, John D; Smith, Charles D

2006-07-01

The covalent attachment of palmitate to specific proteins by the action of palmitoyl acyltransferases (PAT) plays critical roles in the biological activities of several oncoproteins. Two PAT activities are expressed by human cells: type 1 PATs that modify the farnesyl-dependent palmitoylation motif found in H- and N-Ras, and type 2 PATs that modify the myristoyl-dependent palmitoylation motif found in the Src family of tyrosine kinases. We have previously shown that the type 1 PAT HIP14 causes cellular transformation. In the current study, we show that mRNA encoding HIP14 is up-regulated in a number of types of human tumors. To assess the potential of HIP14 and other PATs as targets for new anticancer drugs, we developed three cell-based assays suitable for high-throughput screening to identify inhibitors of these enzymes. Using these screens, five chemotypes, with activity toward either type 1 or type 2 PAT activity, were identified. The activity of the hits were confirmed using assays that quantify the in vitro inhibition of PAT activity, as well as a cell-based assay that determines the abilities of the compounds to prevent the localization of palmitoylated green fluorescent proteins to the plasma membrane. Representative compounds from each chemotype showed broad antiproliferative activity toward a panel of human tumor cell lines and inhibited the growth of tumors in vivo. Together, these data show that PATs, and HIP14 in particular, are interesting new targets for anticancer compounds, and that small molecules with such activity can be identified by high-throughput screening.

Molecular characterisation of a recombinant bovine glycine N-acyltransferase / Christoffel Petrus Stephanus Badenhorst

OpenAIRE

Badenhorst, Christoffel Petrus Stephanus

2010-01-01

Conjugation of glycine to organic acids is an important detoxification mechanism. Metabolites of aspirin and industrial solvents, benzoic acid found in plant material and many endogenous metabolites are detoxified by conjugation to glycine. The enzyme responsible for glycine conjugation, glycine N-acyltransferase (GL YAT), is investigated in this study. The enzyme is also important for the management of organic acidemias which are inherited metabolic diseases. However, not all ...

Role of Wax Ester Synthase/Acyl Coenzyme A:Diacylglycerol Acyltransferase in Oleaginous Streptomyces sp. Strain G25

Science.gov (United States)

Röttig, Annika; Strittmatter, Carl Simon; Schauer, Jennifer; Hiessl, Sebastian; Daniel, Rolf

2016-01-01

ABSTRACT Recently, we isolated a novel Streptomyces strain which can accumulate extraordinarily large amounts of triacylglycerol (TAG) and consists of 64% fatty acids (dry weight) when cultivated with glucose and 50% fatty acids (dry weight) when cultivated with cellobiose. To identify putative gene products responsible for lipid storage and cellobiose utilization, we analyzed its draft genome sequence. A single gene encoding a wax ester synthase/acyl coenzyme A (CoA):diacylglycerol acyltransferase (WS/DGAT) was identified and heterologously expressed in Escherichia coli. The purified enzyme AtfG25 showed acyltransferase activity with C12- or C16-acyl-CoA, C12 to C18 alcohols, or dipalmitoyl glycerol. This acyltransferase exhibits 24% amino acid identity to the model enzyme AtfA from Acinetobacter baylyi but has high sequence similarities to WS/DGATs from other Streptomyces species. To investigate the impact of AtfG25 on lipid accumulation, the respective gene, atfG25, was inactivated in Streptomyces sp. strain G25. However, cells of the insertion mutant still exhibited DGAT activity and were able to store TAG, albeit in lower quantities and at lower rates than the wild-type strain. These findings clearly indicate that AtfG25 has an important, but not exclusive, role in TAG biosynthesis in the novel Streptomyces isolate and suggest the presence of alternative metabolic pathways for lipid accumulation which are discussed in the present study. IMPORTANCE A novel Streptomyces strain was isolated from desert soil, which represents an extreme environment with high temperatures, frequent drought, and nutrient scarcity. We believe that these harsh conditions promoted the development of the capacity for this strain to accumulate extraordinarily large amounts of lipids. In this study, we present the analysis of its draft genome sequence with a special focus on enzymes potentially involved in its lipid storage. Furthermore, the activity and importance of the detected

Characterization of acyl-coenzyme A:diacylglycerol acyltransferase (DGAT) enzyme of human small intestine.

Science.gov (United States)

Hiramine, Yasushi; Tanabe, Toshizumi

2011-06-01

Acyl-coenzyme A:diacylglycerol acyltransferase (DGAT) enzyme plays a significant role in dietary triacylglycerol (TAG) absorption in the small intestine. However, the characteristics of human intestinal DGAT enzyme have not been examined in detail. The aim of our study was to characterize the human intestinal DGAT enzyme by examining acyl-CoA specificity, temperature dependency, and selectivity for 1,2-diacylglycerol (DAG) or 1,3-DAG. We detected DGAT activity of human intestinal microsome and found that the acyl-CoA specificity and temperature dependency of intestinal DGAT coincided with those of recombinant human DGAT1. To elucidate the selectivity of human intestinal DGAT to 1,2-DAG or 1,3-DAG, we conducted acyl-coenzyme A:monoacylglycerol acyltransferase assays using 1- or 2-monoacylglycerol (MAG) as substrates. When 2-MAG was used as acyl acceptor, both 1,2-DAG and TAG were generated; however, when 1-MAG was used, 1,3-DAG was predominantly observed and little TAG was detected. These findings suggest that human small intestinal DGAT, which is mainly encoded by DGAT1, utilizes 1,2-DAG as the substrate to form TAG. This study will contribute to understand the lipid absorption profile in the small intestine.

Blocking Hedgehog release from pancreatic cancer cells increases paracrine signaling potency

NARCIS (Netherlands)

Damhofer, Helene; Veenstra, Veronique L.; Tol, Johanna A. M. G.; van Laarhoven, Hanneke W. M.; Medema, Jan Paul; Bijlsma, Maarten F.

2015-01-01

Members of the Hedgehog (Hh) family of morphogens play crucial roles in development but are also involved in the progression of certain types of cancer. Despite being synthesized as hydrophobic dually lipid-modified molecules, and thus being strongly membrane-associated, Hh ligands are able to

Endogenously produced Indian Hedgehog regulates TGFβ-driven chondrogenesis of human bone marrow stromal/stem cells.

Science.gov (United States)

Handorf, Andrew M; Chamberlain, Connie S; Li, Wan-Ju

2015-04-15

Human bone marrow stromal/stem cells (hBMSCs) have an inherent tendency to undergo hypertrophy when induced into the chondrogenic lineage using transforming growth factor-beta 1 (TGFβ) in vitro, reminiscent of what occurs during endochondral ossification. Surprisingly, Indian Hedgehog (IHH) has received little attention for its role during hBMSC chondrogenesis despite being considered a master regulator of endochondral ossification. In this study, we investigated the role that endogenously produced IHH plays during hBMSC chondrogenesis. We began by analyzing the expression of IHH throughout differentiation using quantitative polymerase chain reaction and found that IHH expression was upregulated dramatically upon chondrogenic induction and peaked from days 9 to 12 of differentiation, which coincided with a concomitant increase in the expression of chondrogenesis- and hypertrophy-related markers, suggesting a potential role for endogenously produced IHH in driving hBMSC chondrogenesis. More importantly, pharmacological inhibition of Hedgehog signaling with cyclopamine or knockdown of IHH almost completely blocked TGFβ1-induced chondrogenesis in hBMSCs, demonstrating that endogenously produced IHH is necessary for hBMSC chondrogenesis. Furthermore, overexpression of IHH was sufficient to drive chondrogenic differentiation, even when TGFβ signaling was inhibited. Finally, stimulation with TGFβ1 induced a significant and sustained upregulation of IHH expression within 3 h that preceded an upregulation in all cartilage-related genes analyzed, and knockdown of IHH blocked the effects of TGFβ1 entirely, suggesting that the effects of TGFβ1 are being mediated through endogenously produced IHH. Together, our findings demonstrate that endogenously produced IHH is playing a critical role in regulating hBMSC chondrogenesis.

Induction of 1-Acylglycerophosphocholine Acyltransferase Genes by Fibrates in the Liver of Rats

OpenAIRE

山崎, 研; 若林, 美智子; 池田, 英里香; 田中, 静代; 坂本, 武史; 光本, 篤史; 工藤, なをみ; 川嶋, 洋一

2012-01-01

The effect of fibrates (clofibric acid, bezafibrate and fenofibrate) on the gene expression and activity of 1-acylglycerophosphocholine acyltransferase (LPCAT) was investigated. The administration of 0.1% (w/w) clofibric acid, bezafibrate or fenofibrate in diet for 14?d to rats induced LPCAT activity in hepatic microsomes in the following order: fenofibrate>bezafibrate>clofibric acid. The LPCAT induced by fenofibrate preferred to arachidonoyl-CoA and linoleoyl-CoA to a greater extent than did...

Cryptosporidium erinacei and C. parvum in a group of overwintering hedgehogs

Czech Academy of Sciences Publication Activity Database

Hofmannová, L.; Hauptman, K.; Huclová, K.; Květoňová, Dana; Sak, Bohumil; Kváč, Martin

2016-01-01

Roč. 56, č. 1 (2016), s. 15-20 ISSN 0932-4739 R&D Projects: GA ČR GA15-01090S Institutional support: RVO:60077344 Keywords : Cryptosporidiosis * Erinaceus europaeus * European hedgehog Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 2.581, year: 2016

LncRNA EGOT Promotes Tumorigenesis Via Hedgehog Pathway in Gastric Cancer.

Science.gov (United States)

Peng, Wei; Wu, Jianzhong; Fan, Hong; Lu, Jianwei; Feng, Jifeng

2017-12-05

Gastric cancer (GC) is one of the mostly terminal malignancies with poor prognosis. Long noncoding RNA EGOT (EGOT) acts as a crucial regulator in the breast cancer. However, the function of EGOT in GC remains unknown. This work was to explore the clinical value and biological significance of EGOT in GC. EGOT levels in GC tissue and cell were analyzed by qRT-PCR. After knockdown of EGOT, GC cell growth and cycle progression were detected. The expression of EGOT was observably elevated in GC. Upregulation of EGOT was related with lymphatic metastasis and TNM stage. In addition, knockdown of EGOT by siRNA could significantly inhibit GC cell proliferation and arrest cycle progression in G1 phase. Moreover, EGOT mediated cyclin D1 expression in GC cells which was regulated by Hedgehog pathway. Further, loss of EGOT downregulated Hedgehog signaling pathway in GC cells. EGOT functions as an oncogene in GC, and may be useful as a conceivable diagnostic and prognostic biomarker for GC tumorigenesis.

Non-destructive pollution exposure assessment in the European hedgehog (Erinaceus europaeus): II. Hair and spines as indicators of endogenous metal and As concentrations

International Nuclear Information System (INIS)

D'Have, Helga; Scheirs, Jan; Mubiana, Valentine Kayawe; Verhagen, Ron; Blust, Ronny; Coen, Wim de

2006-01-01

The role of hair and spines of the European hedgehog as non-destructive monitoring tools of metal (Ag, Al, Cd, Co, Cr, Cu, Fe, Ni, Pb, Zn) and As pollution in terrestrial ecosystems was investigated. Our results showed that mean pollution levels of a random sample of hedgehogs in Flanders are low to moderate. Yet, individual hedgehogs may be at risk for metal toxicity. Tissue distribution analyses (hair, spines, liver, kidney, muscle and fat tissue) indicated that metals and As may reach considerable concentrations in external tissues, such as hair and spines. Positive relationships were observed between concentrations in hair and those in liver, kidney and muscle for Al, Co, Cr, Cu, and Pb (0.43 < r < 0.85). Spine concentrations were positively related to liver, kidney and muscle concentrations for Cd, Co, Cr, Cu and Pb (0.37 < r < 0.62). Hair Ag, As, Fe and Zn and spine Ag, Al, As and Fe were related to metal concentrations in one or two of the investigated internal tissues (0.31 < r < 0.45). The regression models presented here may be used to predict metal and As concentrations in internal tissues of hedgehogs when concentrations in hair or spines are available. The present study demonstrated the possibility of using hair and spines for non-destructive monitoring of metal and As pollution in hedgehogs. - Hedgehog hair and spines are promising non-destructive biomonitoring tools of terrestrial metal pollution

Non-destructive pollution exposure assessment in the European hedgehog (Erinaceus europaeus): II. Hair and spines as indicators of endogenous metal and As concentrations

Energy Technology Data Exchange (ETDEWEB)

D' Have, Helga [Ecophysiology, Biochemistry and Toxicology Group, Department of Biology, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium)]. E-mail: helga.dhave@ua.ac.be; Scheirs, Jan [Evolutionary Biology Group, Department of Biology, University of Antwerp, B-2020 Antwerp (Belgium); Mubiana, Valentine Kayawe [Ecophysiology, Biochemistry and Toxicology Group, Department of Biology, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium); Verhagen, Ron [Evolutionary Biology Group, Department of Biology, University of Antwerp, B-2020 Antwerp (Belgium); Blust, Ronny [Ecophysiology, Biochemistry and Toxicology Group, Department of Biology, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium); Coen, Wim de [Ecophysiology, Biochemistry and Toxicology Group, Department of Biology, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium)

2006-08-15

The role of hair and spines of the European hedgehog as non-destructive monitoring tools of metal (Ag, Al, Cd, Co, Cr, Cu, Fe, Ni, Pb, Zn) and As pollution in terrestrial ecosystems was investigated. Our results showed that mean pollution levels of a random sample of hedgehogs in Flanders are low to moderate. Yet, individual hedgehogs may be at risk for metal toxicity. Tissue distribution analyses (hair, spines, liver, kidney, muscle and fat tissue) indicated that metals and As may reach considerable concentrations in external tissues, such as hair and spines. Positive relationships were observed between concentrations in hair and those in liver, kidney and muscle for Al, Co, Cr, Cu, and Pb (0.43 < r < 0.85). Spine concentrations were positively related to liver, kidney and muscle concentrations for Cd, Co, Cr, Cu and Pb (0.37 < r < 0.62). Hair Ag, As, Fe and Zn and spine Ag, Al, As and Fe were related to metal concentrations in one or two of the investigated internal tissues (0.31 < r < 0.45). The regression models presented here may be used to predict metal and As concentrations in internal tissues of hedgehogs when concentrations in hair or spines are available. The present study demonstrated the possibility of using hair and spines for non-destructive monitoring of metal and As pollution in hedgehogs. - Hedgehog hair and spines are promising non-destructive biomonitoring tools of terrestrial metal pollution.

Non-destructive pollution exposure assessment in the European hedgehog (Erinaceus europaeus): II. Hair and spines as indicators of endogenous metal and As concentrations.

Science.gov (United States)

D'Havé, Helga; Scheirs, Jan; Mubiana, Valentine Kayawe; Verhagen, Ron; Blust, Ronny; De Coen, Wim

2006-08-01

The role of hair and spines of the European hedgehog as non-destructive monitoring tools of metal (Ag, Al, Cd, Co, Cr, Cu, Fe, Ni, Pb, Zn) and As pollution in terrestrial ecosystems was investigated. Our results showed that mean pollution levels of a random sample of hedgehogs in Flanders are low to moderate. Yet, individual hedgehogs may be at risk for metal toxicity. Tissue distribution analyses (hair, spines, liver, kidney, muscle and fat tissue) indicated that metals and As may reach considerable concentrations in external tissues, such as hair and spines. Positive relationships were observed between concentrations in hair and those in liver, kidney and muscle for Al, Co, Cr, Cu, and Pb (0.43 Spine concentrations were positively related to liver, kidney and muscle concentrations for Cd, Co, Cr, Cu and Pb (0.37 spine Ag, Al, As and Fe were related to metal concentrations in one or two of the investigated internal tissues (0.31 hedgehogs when concentrations in hair or spines are available. The present study demonstrated the possibility of using hair and spines for non-destructive monitoring of metal and As pollution in hedgehogs.

Targeting Sonic Hedgehog Signaling by Compounds and Derivatives from Natural Products

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Yu-Chuen Huang

2013-01-01

Full Text Available Cancer stem cells (CSCs are a major cause of cancer treatment failure, relapse, and drug resistance and are known to be responsible for cancer cell invasion and metastasis. The Sonic hedgehog (Shh signaling pathway is crucial to embryonic development. Intriguingly, the aberrant activation of the Shh pathway plays critical roles in developing CSCs and leads to angiogenesis, migration, invasion, and metastasis. Natural compounds and chemical structure modified derivatives from complementary and alternative medicine have received increasing attention as cancer chemopreventives, and their antitumor effects have been demonstrated both in vitro and in vivo. However, reports for their bioactivity against CSCs and specifically targeting Shh signaling remain limited. In this review, we summarize investigations of the compounds cyclopamine, curcumin, epigallocatechin-3-gallate, genistein, resveratrol, zerumbone, norcantharidin, and arsenic trioxide, with a focus on Shh signaling blockade. Given that Shh signaling antagonism has been clinically proven as effective strategy against CSCs, this review may be exploitable for development of novel anticancer agents from complementary and alternative medicine.

Novel hedgehog-like 5 V LiCoPO4 positive electrode material for rechargeable lithium battery

Science.gov (United States)

Wang, Fei; Yang, Jun; NuLi, Yanna; Wang, Jiulin

2011-05-01

Hedgehog-like LiCoPO4 with hierarchical microstructures is first synthesized via a simple solvothermal process in water-benzyl alcohol mixed solvent at 200 °C. Morphology and crystalline structure of the samples are characterized by scanning electron microscope, transmission electron microscopy and X-ray diffraction. The hedgehog-like LiCoPO4 microstructures in the size of about 5-8 μm are composed of large numbers of nanorods in diameter of ca. 40 nm and length of ca. 1 μm, which are coated with a carbon layer of ca. 8 nm in thickness by in situ carbonization of glucose during the solvothermal reaction. As a 5 V positive electrode material for rechargeable lithium battery, the hedgehog-like LiCoPO4 delivers an initial discharge capacity of 136 mAh g-1 at 0.1 C rate and retains its 91% after 50 cycles, showing much better electrochemical performances than sub-micrometer LiCoPO4 synthesized by conventional high-temperature solid-state reaction.

TEST and EVALUATION REPORT FOR THE HEDGEHOG-II PACKAGING SYSTEMS DOT-7A TYPE A CONTAINER

International Nuclear Information System (INIS)

KELLY, D.L.

2003-01-01

This report documents the US. Department of Transportation Specification 7A (DOT-7A) Type A compliance test and evaluation results for the Hedgehog-II packaging systems. The approved Hedgehog-II packaging configurations provide primary and secondary containment. The approved packaging configurations described within this report are designed to ship Type A quantities of radioactive materials, normal form. Contents may be in solid or liquid form. Liquids transported in the approved 1 L glass bottle assembly shall have a specific gravity of less than or equal to 1.6. Liquids transported in all other approved configurations shall have a specific gravity of less than or equal to 2.0. The solid contents, including packaging, are limited in weight to the gross weight of the as-tested liquids and bottles. The approved Hedgehog-II packaging configurations described in this report may be transported by air, and have been evaluated as meeting the applicable International Air Transport Association/International Civil Aviation Organization (IATA/ICAO) Dangerous Goods Regulations in addition to the DOT requirements

Exosomes Derived from Human Bone Marrow Mesenchymal Stem Cells Promote Tumor Growth Through Hedgehog Signaling Pathway

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Jin Qi

2017-08-01

Full Text Available Background/Aims: Mesenchymal stem/stromal cells (MSCs are known to home to sites of tumor microenvironments where they participate in the formation of the tumor microenvironment and to interplay with tumor cells. However, the potential functional effects of MSCs on tumor cell growth are controversial. Here, we, from the view of bone marrow MSC-derived exosomes, study the molecular mechanism of MSCs on the growth of human osteosarcoma and human gastric cancer cells. Methods: MSCs derived from human bone marrow (hBMSCs were isolated and cultured in complete DMEM/F12 supplemented with 10% exosome-depleted fetal bovine serum and 1% penicillin-streptomycin, cell culture supernatants containing exosomes were harvested and exosome purification was performed by ultracentrifugation. Osteosarcoma (MG63 and gastric cancer (SGC7901 cells, respectively, were treated with hBMSC-derived exosomes in the presence or absence of a small molecule inhibitor of Hedgehog pathway. Cell viability was measured by transwell invasion assay, scratch migration assay and CCK-8 test. The expression of the signaling molecules Smoothened, Patched-1, Gli1 and the ligand Shh were tested by western blot and RT-PCR. Results: In this study, we found that hBMSC-derived exosomes promoted MG63 and SGC7901 cell growth through the activation of Hedgehog signaling pathway. Inhibition of Hedgehog signaling pathway significantly suppressed the process of hBMSC-derived exosomes on tumor growth. Conclusion: Our findings demonstrated the new roles of hedgehog signaling pathway in the hBMSCs-derived exosomes induced tumor progression.

Evolutionary genomics and adaptive evolution of the Hedgehog gene family (Shh, Ihh and Dhh in vertebrates.

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Joana Pereira

Full Text Available The Hedgehog (Hh gene family codes for a class of secreted proteins composed of two active domains that act as signalling molecules during embryo development, namely for the development of the nervous and skeletal systems and the formation of the testis cord. While only one Hh gene is found typically in invertebrate genomes, most vertebrates species have three (Sonic hedgehog--Shh; Indian hedgehog--Ihh; and Desert hedgehog--Dhh, each with different expression patterns and functions, which likely helped promote the increasing complexity of vertebrates and their successful diversification. In this study, we used comparative genomic and adaptive evolutionary analyses to characterize the evolution of the Hh genes in vertebrates following the two major whole genome duplication (WGD events. To overcome the lack of Hh-coding sequences on avian publicly available databases, we used an extensive dataset of 45 avian and three non-avian reptilian genomes to show that birds have all three Hh paralogs. We find suggestions that following the WGD events, vertebrate Hh paralogous genes evolved independently within similar linkage groups and under different evolutionary rates, especially within the catalytic domain. The structural regions around the ion-binding site were identified to be under positive selection in the signaling domain. These findings contrast with those observed in invertebrates, where different lineages that experienced gene duplication retained similar selective constraints in the Hh orthologs. Our results provide new insights on the evolutionary history of the Hh gene family, the functional roles of these paralogs in vertebrate species, and on the location of mutational hotspots.

Evolutionary genomics and adaptive evolution of the Hedgehog gene family (Shh, Ihh and Dhh) in vertebrates.

Science.gov (United States)

Pereira, Joana; Johnson, Warren E; O'Brien, Stephen J; Jarvis, Erich D; Zhang, Guojie; Gilbert, M Thomas P; Vasconcelos, Vitor; Antunes, Agostinho

2014-01-01

The Hedgehog (Hh) gene family codes for a class of secreted proteins composed of two active domains that act as signalling molecules during embryo development, namely for the development of the nervous and skeletal systems and the formation of the testis cord. While only one Hh gene is found typically in invertebrate genomes, most vertebrates species have three (Sonic hedgehog--Shh; Indian hedgehog--Ihh; and Desert hedgehog--Dhh), each with different expression patterns and functions, which likely helped promote the increasing complexity of vertebrates and their successful diversification. In this study, we used comparative genomic and adaptive evolutionary analyses to characterize the evolution of the Hh genes in vertebrates following the two major whole genome duplication (WGD) events. To overcome the lack of Hh-coding sequences on avian publicly available databases, we used an extensive dataset of 45 avian and three non-avian reptilian genomes to show that birds have all three Hh paralogs. We find suggestions that following the WGD events, vertebrate Hh paralogous genes evolved independently within similar linkage groups and under different evolutionary rates, especially within the catalytic domain. The structural regions around the ion-binding site were identified to be under positive selection in the signaling domain. These findings contrast with those observed in invertebrates, where different lineages that experienced gene duplication retained similar selective constraints in the Hh orthologs. Our results provide new insights on the evolutionary history of the Hh gene family, the functional roles of these paralogs in vertebrate species, and on the location of mutational hotspots.

Stromal Indian hedgehog signaling is required for intestinal adenoma formation in mice

NARCIS (Netherlands)

Büller, Nikè V J A; Rosekrans, Sanne L.; Metcalfe, Ciara; Heijmans, Jarom; Van Dop, Willemijn A.; Fessler, Evelyn; Jansen, Marnix; Ahn, Christina; Vermeulen, Jacqueline L M; Westendorp, B. Florien; Robanus-Maandag, Els C.; Offerhaus, G. Johan; Medema, Jan Paul; D'Haens, Geert R A M; Wildenberg, Manon E.; De Sauvage, Frederic J.; Muncan, Vanesa; Van Den Brink, Gijs R.

2015-01-01

BACKGROUND & AIMS: Indian hedgehog (IHH) is an epithelial-derived signal in the intestinal stroma, inducing factors that restrict epithelial proliferation and suppress activation of the immune system. In addition to these rapid effects of IHH signaling, IHH is required to maintain a stromal

A soluble diacylglycerol acyltransferase is involved in triacylglycerol biosynthesis in the oleaginous yeast Rhodotorula glutinis.

Science.gov (United States)

Rani, Sapa Hima; Saha, Saikat; Rajasekharan, Ram

2013-01-01

The biosynthesis of triacylglycerol (TAG) occurs in the microsomal membranes of eukaryotes. Here, we report the identification and functional characterization of diacylglycerol acyltransferase (DGAT), a member of the 10 S cytosolic TAG biosynthetic complex (TBC) in Rhodotorula glutinis. Both a full-length and an N-terminally truncated cDNA clone of a single gene were isolated from R. glutinis. The DGAT activity of the protein encoded by RgDGAT was confirmed in vivo by the heterologous expression of cDNA in a Saccharomyces cerevisiae quadruple mutant (H1246) that is defective in TAG synthesis. RgDGAT overexpression in yeast was found to be capable of acylating diacylglycerol (DAG) in an acyl-CoA-dependent manner. Quadruple mutant yeast cells exhibit growth defects in the presence of oleic acid, but wild-type yeast cells do not. In an in vivo fatty acid supplementation experiment, RgDGAT expression rescued quadruple mutant growth in an oleate-containing medium. We describe a soluble acyl-CoA-dependent DAG acyltransferase from R. glutinis that belongs to the DGAT3 class of enzymes. The study highlights the importance of an alternative TAG biosynthetic pathway in oleaginous yeasts.

Hedgehog signaling pathway in neuroblastoma differentiation.

Science.gov (United States)

Souzaki, Ryota; Tajiri, Tatsuro; Souzaki, Masae; Kinoshita, Yoshiaki; Tanaka, Sakura; Kohashi, Kenichi; Oda, Yoshinao; Katano, Mitsuo; Taguchi, Tomoaki

2010-12-01

The hedgehog (Hh) signaling pathway is activated in some adult cancers. On the other hand, the Hh signaling pathway plays an important role in the development of the neural crest in embryos. The aim of this study is to show the activation of Hh signaling pathway in neuroblastoma (NB), a pediatric malignancy arising from neural crest cells, and to reveal the meaning of the Hh signaling pathway in NB development. This study analyzed the expression of Sonic hedgehog (Shh), GLI1, and Patched 1 (Ptch1), transactivators of Hh signaling pathway, by immunohistochemistry in 82 NB and 10 ganglioneuroblastoma cases. All 92 cases were evaluated for the status of MYCN amplification. Of the 92 cases, 67 (73%) were positive for Shh, 62 cases (67%) were positive for GLI1, and 73 cases (79%) were positive for Ptch1. Only 2 (10%) of the 20 cases with MYCN amplification were positive for Shh and GLI1, and 4 cases (20%) were positive for Ptch1 (MYCN amplification vs no MYCN amplification, P ≦ .01). The percentage of GLI1-positive cells in the cases with INSS stage 1 without MYCN amplification was significantly higher than that with INSS stage 4. Of 72 cases without MYCN amplification, 60 were GLI1-positive. Twelve cases were GLI1-negative, and the prognosis of the GLI1-positive cases was significantly better than that of the GLI1-negative cases (P = .015). Most of NBs without MYCN amplification were positive for Shh, GLI1, and Ptch1. In the cases without MYCN amplification, the high expression of GLI1 was significantly associated with early clinical stage and a good prognosis of the patients. In contrast to adult cancers, the activation of the Hh signaling pathway in NB may be associated with the differentiation of the NB. Copyright © 2010 Elsevier Inc. All rights reserved.

Dispatched and Scube Mediate the Efficient Secretion of the Cholesterol-Modified Hedgehog Ligand

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Hanna Tukachinsky

2012-08-01

Full Text Available The Hedgehog (Hh signaling pathway plays critical roles in metazoan development and in cancer. How the Hh ligand is secreted and spreads to distant cells is unclear, given its covalent modification with a hydrophobic cholesterol molecule, which makes it stick to membranes. We demonstrate that Hh ligand secretion from vertebrate cells is accomplished via two distinct and synergistic cholesterol-dependent binding events, mediated by two proteins that are essential for vertebrate Hh signaling: the membrane protein Dispatched (Disp and a member of the Scube family of secreted proteins. Cholesterol modification is sufficient for a heterologous protein to interact with Scube and to be secreted in a Scube-dependent manner. Disp and Scube recognize different structural aspects of cholesterol similarly to how Niemann-Pick disease proteins 1 and 2 interact with cholesterol, suggesting a hand-off mechanism for transferring Hh from Disp to Scube. Thus, Disp and Scube cooperate to dramatically enhance the secretion and solubility of the cholesterol-modified Hh ligand.

Indian hedgehog (Ihh) both promotes and restricts thymocyte differentiation.

Science.gov (United States)

Outram, Susan V; Hager-Theodorides, Ariadne L; Shah, Divya K; Rowbotham, Nicola J; Drakopoulou, Ekati; Ross, Susan E; Lanske, Beate; Dessens, Johannes T; Crompton, Tessa

2009-03-05

We show that Indian Hedgehog (Ihh) regulates T-cell development and homeostasis in both fetal and adult thymus, controlling thymocyte number. Fetal Ihh(-/-) thymi had reduced differentiation to double-positive (DP) cell and reduced cell numbers compared with wild-type littermates. Surprisingly, fetal Ihh(+/-) thymi had increased thymocyte numbers and proportion of DP cells relative to wild type, indicating that Ihh also negatively regulates thymocyte development. In vitro treatment of thymus explants with exogenous recombinant Hedgehog protein promoted thymocyte development in Ihh(-/-) thymi but inhibited thymocyte development in Ihh(+/-), confirming both positive and negative regulatory functions of Ihh. Analysis of Rag(-/-)Ihh(+/-) thymi showed that Ihh promotes T-cell development before pre-T-cell receptor (pre-TCR) signaling, but negatively regulates T-cell development only after pre-TCR signaling has taken place. We show that Ihh is most highly expressed by the DP population and that Ihh produced by DP cells feeds back to negatively regulate the differentiation and proliferation of their double-negative progenitors. Thus, differentiation from double-negative to DP cell, and hence the size of the DP population, is dependent on the concentration of Ihh in the thymus. Analysis of Ihh conditional knockout and heterozygote adult mice showed that Ihh also influences thymocyte number in the adult.

Hedgehog Signaling Regulates the Survival of Gastric Cancer Cells by Regulating the Expression of Bcl-2

Science.gov (United States)

Han, Myoung-Eun; Lee, Young-Suk; Baek, Sun-Yong; Kim, Bong-Seon; Kim, Jae-Bong; Oh, Sae-Ock

2009-01-01

Gastric cancer is the second most common cause of cancer deaths worldwide. The underlying molecular mechanisms of its carcinogenesis are relatively poorly characterized. Hedgehog (Hh) signaling, which is critical for development of various organs including the gastrointestinal tract, has been associated with gastric cancer. The present study was undertaken to reveal the underlying mechanism by which Hh signaling controls gastric cancer cell proliferation. Treatment of gastric cancer cells with cyclopamine, a specific inhibitor of Hh signaling pathway, reduced proliferation and induced apoptosis of gastric cancer cells. Cyclopamine treatment induced cytochrome c release from mitochondria and cleavage of caspase 9. Moreover, Bcl-2 expression was significantly reduced by cyclopamine treatment. These results suggest that Hh signaling regulates the survival of gastric cancer cells by regulating the expression of Bcl-2. PMID:19742123

Effect of γ irradiation on the activity of lecithin-cholesterol acyltransferase in plasma of the rat

International Nuclear Information System (INIS)

Dousset, N.; Douste-Blazy, L.

1975-01-01

Plasma cholesterol and lecithin-cholesterol-acyl-transferase activity are studied in irradiated rats. Ionizing radiations cause an increase of cholesterol levels in plasma, concerning mainly ester fraction. Lecithin-cholesterol-acyltransferase activity in plasma of irradiated rats is lowered 48 hours after exposure. This decreased rate of LCAT is probably the consequence of the post-irradiation hypercholesterolemia [fr

Stromal Indian hedgehog signaling is required for intestinal adenoma formation in mice

NARCIS (Netherlands)

Büller, Nikè V. J. A.; Rosekrans, Sanne L.; Metcalfe, Ciara; Heijmans, Jarom; van Dop, Willemijn A.; Fessler, Evelyn; Jansen, Marnix; Ahn, Christina; Vermeulen, Jacqueline L. M.; Westendorp, B. Florien; Robanus-Maandag, Els C.; Offerhaus, G. Johan; Medema, Jan Paul; D'Haens, Geert R. A. M.; Wildenberg, Manon E.; de Sauvage, Frederic J.; Muncan, Vanesa; van den Brink, Gijs R.

2015-01-01

Indian hedgehog (IHH) is an epithelial-derived signal in the intestinal stroma, inducing factors that restrict epithelial proliferation and suppress activation of the immune system. In addition to these rapid effects of IHH signaling, IHH is required to maintain a stromal phenotype in which

In vivo RNAi screen reveals neddylation genes as novel regulators of Hedgehog signaling.

Directory of Open Access Journals (Sweden)

Juan Du

Full Text Available Hedgehog (Hh signaling is highly conserved in all metazoan animals and plays critical roles in many developmental processes. Dysregulation of the Hh signaling cascade has been implicated in many diseases, including cancer. Although key components of the Hh pathway have been identified, significant gaps remain in our understanding of the regulation of individual Hh signaling molecules. Here, we report the identification of novel regulators of the Hh pathway, obtained from an in vivo RNA interference (RNAi screen in Drosophila. By selectively targeting critical genes functioning in post-translational modification systems utilizing ubiquitin (Ub and Ub-like proteins, we identify two novel genes (dUba3 and dUbc12 that negatively regulate Hh signaling activity. We provide in vivo and in vitro evidence illustrating that dUba3 and dUbc12 are essential components of the neddylation pathway; they function in an enzyme cascade to conjugate the ubiquitin-like NEDD8 modifier to Cullin proteins. Neddylation activates the Cullin-containing ubiquitin ligase complex, which in turn promotes the degradation of Cubitus interruptus (Ci, the downstream transcription factor of the Hh pathway. Our study reveals a conserved molecular mechanism of the neddylation pathway in Drosophila and sheds light on the complex post-translational regulations in Hh signaling.

Plasma lecithin : cholesterol acyltransferase activity modifies the inverse relationship of C-reactive protein with HDL cholesterol in nondiabetic men

NARCIS (Netherlands)

Dullaart, R. P. F.; Perton, F.; Kappelle, P.J.W.H.; de Vries, R.; Sluiter, W. J.; van Tol, A.

Lecithin:cholesterol acyltransferase (LCAT) is instrumental in high-density lipoprotein (HDL) maturation, but high LCAT levels do not predict low cardiovascular risk. LCAT may affect antioxidative or anti-inflammatory properties of HDL We determined the relationship of plasma high-sensitivity

Indian hedgehog regulates intestinal stem cell fate through epithelial-mesenchymal interactions during development

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Kosinski, C.; Stange, D.E.; Xu, C.; Chan, A.S.; Ho, C.; Yuen, S.T.; Mifflin, R.C.; Powell, D.W.; Clevers, H.; Leung, S.Y.; Chen, X.N.

2010-01-01

BACKGROUND & AIMS: Intestinal stem cells (ISCs) are regulated by the mesenchymal environment via physical interaction and diffusible factors. We examined the role of Indian hedgehog (Ihh) in mesenchymal organization and the mechanisms by which perturbations in epithelial-mesenchymal interactions

Altered regulation of lipid biosynthesis in a mutant of Arabidopsis deficient in chloroplast glycerol-3-phosphate acyltransferase activity

International Nuclear Information System (INIS)

Kunst, L.; Browse, J.; Somerville, C.

1988-01-01

The leaf membrane lipids of many plant species, including Arabidopsis thaliana (L.) Heynh., are synthesized by two complementary pathways that are associated with the chloroplast and the endoplasmic reticulum. By screening directly for alterations in lipid acyl-group composition, the authors have identified several mutants of Arabidopsis that lack the plastid pathway because of a deficiency in activity of the first enzyme in the plastid pathway of glycerolipid synthesis, acyl-ACP:sn-glycerol-3-phosphate acyltransferase. The lesion results in an increased synthesis of lipids by the cytoplasmic pathway that largely compensates for the loss of the plastid pathway and provides nearly normal amounts of all the lipids required for chloroplast biogenesis. However, the fatty acid composition of the leaf membrane lipids of the mutants is altered because the acyltransferases associated with the two pathways normally exhibit different substrate specificities. The remarkable flexibility of the system provides an insight into the nature of the regulatory mechanisms that allocate lipids for membrane biogenesis

Studies on the substrate and stereo/regioselectivity of adipose triglyceride lipase, hormone-sensitive lipase, and diacylglycerol-O-acyltransferases.

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Eichmann, Thomas O; Kumari, Manju; Haas, Joel T; Farese, Robert V; Zimmermann, Robert; Lass, Achim; Zechner, Rudolf

2012-11-30

Adipose triglyceride lipase (ATGL) is rate-limiting for the initial step of triacylglycerol (TAG) hydrolysis, generating diacylglycerol (DAG) and fatty acids. DAG exists in three stereochemical isoforms. Here we show that ATGL exhibits a strong preference for the hydrolysis of long-chain fatty acid esters at the sn-2 position of the glycerol backbone. The selectivity of ATGL broadens to the sn-1 position upon stimulation of the enzyme by its co-activator CGI-58. sn-1,3 DAG is the preferred substrate for the consecutive hydrolysis by hormone-sensitive lipase. Interestingly, diacylglycerol-O-acyltransferase 2, present at the endoplasmic reticulum and on lipid droplets, preferentially esterifies sn-1,3 DAG. This suggests that ATGL and diacylglycerol-O-acyltransferase 2 act coordinately in the hydrolysis/re-esterification cycle of TAGs on lipid droplets. Because ATGL preferentially generates sn-1,3 and sn-2,3, it suggests that TAG-derived DAG cannot directly enter phospholipid synthesis or activate protein kinase C without prior isomerization.

BMP and Hedgehog Regulate Distinct AGM Hematopoietic Stem Cells Ex Vivo

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Mihaela Crisan

2016-03-01

Full Text Available Hematopoietic stem cells (HSC, the self-renewing cells of the adult blood differentiation hierarchy, are generated during embryonic stages. The first HSCs are produced in the aorta-gonad-mesonephros (AGM region of the embryo through endothelial to a hematopoietic transition. BMP4 and Hedgehog affect their production and expansion, but it is unknown whether they act to affect the same HSCs. In this study using the BRE GFP reporter mouse strain that identifies BMP/Smad-activated cells, we find that the AGM harbors two types of adult-repopulating HSCs upon explant culture: One type is BMP-activated and the other is a non-BMP-activated HSC type that is indirectly controlled by Hedgehog signaling through the VEGF pathway. Transcriptomic analyses demonstrate that the two HSC types express distinct but overlapping genetic programs. These results revealing the bifurcation in HSC types at early embryonic stages in the AGM explant model suggest that their development is dependent upon the signaling molecules in the microenvironment.

Nondestructive pollution exposure assessment in the European hedgehog (Erinaceus europaeus): I. Relationships between concentrations of metals and arsenic in hair, spines, and soil.

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D'Havé, Helga; Scheirs, Jan; Mubiana, Valentine Kayawe; Verhagen, Ron; Blust, Ronny; De Coen, Wim

2005-09-01

Conventional metal exposure assessment in terrestrial mammals is generally based on organ analyses of sacrificed animals. Few studies on mammals use nondestructive methodologies despite the growing ethical concern over the use of destructive sampling. Nondestructive methods involve minimal stress to populations and permit successive biomonitoring of the same populations and individuals. In the present study we assessed metal exposure of hedgehogs (Erinaceus europaeus) by investigating relationships between concentrations of metals (Ag, Al, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Zn) and As in soil samples and in hair and spines of hedgehogs. Samples were collected in seven study sites along a metal pollution gradient, characterized by decreasing total soil Ag, As, Cd, Cu, Ni, and Pb concentrations with increasing distance from a nonferrous metallurgic factory. For a number of elements, soil contamination was related both to distance to the smelter and to habitat. Soil concentrations were positively related to levels in hair and spines for Ag, As, Cd, and Pb and thus to hedgehog exposure. Metal concentrations in soil did not relate to metal concentrations in hair and spines for essential elements (e.g., Cu, Fe, Mn, Ni, and Zn), except Co in hair and soil. Our results demonstrate that, at least for nonessential elements, concentrations in soils can be used to predict contamination of these elements in hedgehogs or vice versa. Furthermore, hedgehog exposure increased toward the smelter and was higher for hedgehogs foraging in grasslands than for animals foraging in the forest. Moreover, we believe that hair and spines are promising tools in terrestrial wildlife exposure assessment studies of metals and As.

Photoaffinity Labeling of Developing Jojoba Seed Microsomal Membranes with a Photoreactive Analog of Acyl-Coenzyme A (Acyl-CoA) (Identification of a Putative Acyl-CoA:Fatty Alcohol Acyltransferase.

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Shockey, J. M.; Rajasekharan, R.; Kemp, J. D.

1995-01-01

Jojoba (Simmondsia chinensis, Link) is the only plant known that synthesizes liquid wax. The final step in liquid wax biosynthesis is catalyzed by an integral membrane enzyme, fatty acyl-coenzyme A (CoA):fatty alcohol acyltransferase, which transfers an acyl chain from acyl-CoA to a fatty alcohol to form the wax ester. To purify the acyltransferase, we have labeled the enzyme with a radioiodinated, photoreactive analog of acyl-CoA, 12-[N-(4-azidosalicyl)amino] dodecanoyl-CoA (ASD-CoA). This molecule acts as an inhibitor of acyltransferase activity in the dark and as an irreversible inhibitor upon exposure to ultraviolet light. Oleoyl-CoA protects enzymatic activity in a concentration-dependent manner. Photolysis of microsomal membranes with labeled ASD-CoA resulted in strong labeling of two polypeptides of 57 and 52 kD. Increasing concentrations of oleoyl-CoA reduced the labeling of the 57-kD polypeptide dramatically, whereas the labeling of the 52-kD polypeptide was much less responsive to oleoyl-CoA. Also, unlike the other polypeptide, the labeling of the 57-kD polypeptide was enhanced considerably when photolyzed in the presence of dodecanol. These results suggest that a 57-kD polypeptide from jojoba microsomes may be the acyl-CoA:fatty alcohol acyltransferase.

Inhibition of Notch1 promotes hedgehog signalling in a HES1-dependent manner in chondrocytes and exacerbates experimental osteoarthritis.

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Lin, Neng-Yu; Distler, Alfiya; Beyer, Christian; Philipi-Schöbinger, Ariella; Breda, Silvia; Dees, Clara; Stock, Michael; Tomcik, Michal; Niemeier, Andreas; Dell'Accio, Francesco; Gelse, Kolja; Mattson, Mark P; Schett, Georg; Distler, Jörg Hw

2016-11-01

Notch ligands and receptors have recently been shown to be differentially expressed in osteoarthritis (OA). We aim to further elucidate the functional role of Notch signalling in OA using Notch1 antisense transgenic (Notch1 AS) mice. Notch and hedgehog signalling were analysed by real-time PCR and immunohistochemistry. Notch-1 AS mice were employed as a model of impaired Notch signalling in vivo. Experimental OA was induced by destabilisation of the medial meniscus (DMM). The extent of cartilage destruction and osteophyte formation was analysed by safranin-O staining with subsequent assessment of the Osteoarthritis Research Society International (OARSI) and Mankin scores and µCT scanning. Collagen X staining was used as a marker of chondrocyte hypertrophy. The role of hairy/enhancer of split 1 (Hes-1) was investigated with knockdown and overexpression experiments. Notch signalling was activated in human and murine OA with increased expression of Jagged1, Notch-1, accumulation of the Notch intracellular domain 1 and increased transcription of Hes-1. Notch1 AS mice showed exacerbated OA with increases in OARSI scores, osteophyte formation, increased subchondral bone plate density, collagen X and osteocalcin expression and elevated levels of Epas1 and ADAM-TS5 mRNA. Inhibition of the Notch pathway induced activation of hedgehog signalling with induction of Gli-1 and Gli-2 and increased transcription of hedgehog target genes. The regulatory effects of Notch signalling on Gli-expression were mimicked by Hes-1. Inhibition of Notch signalling activates hedgehog signalling, enhances chondrocyte hypertrophy and exacerbates experimental OA including osteophyte formation. These data suggest that the activation of the Notch pathway may limit aberrant hedgehog signalling in OA. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Sonic hedgehog expression correlates with fundic gland differentiation in the adult gastrointestinal tract

NARCIS (Netherlands)

van den Brink, G. R.; Hardwick, J. C. H.; Nielsen, C.; Xu, C.; ten Kate, F. J.; Glickman, J.; van Deventer, S. J. H.; Roberts, D. J.; Peppelenbosch, M. P.

2003-01-01

Background: Sonic hedgehog (Shh) is an important endodermal morphogenetic signal during the development of the vertebrate gut. It controls gastrointestinal patterning in general, and gastric gland formation in particular. We have previously shown that Shh regulates gastric gland proliferation in the

Effect of growth hormone replacement therapy on plasma lecithin:cholesterol acyltransferase and lipid transfer protein activities in growth hormone-deficient adults

NARCIS (Netherlands)

J.A. Beentjes; A. van Tol (Arie); W.J. Sluiter (Wim); R.P.F. Dullaart (Robin)

2000-01-01

textabstractThe effects of growth hormone (GH) replacement on plasma lecithin:cholesterol acyltransferase (LCAT), cholesteryl ester transfer protein (CETP), and phospholipid transfer protein (PLTP), factors involved in high density lipoprotein (HDL) metabolism, are

Targeting the Hedgehog pathway in cancer: can the spines be smoothened?

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Ailles, Laurie; Siu, Lillian L

2011-04-15

Aberrant Hedgehog (Hh) pathway signaling has been suggested to play a role in the development of multiple solid tumors and hematologic malignancies. GDC-0449 is a novel first-in-human, first-in-class smoothened (SMO) inhibitor, which has completed its phase I evaluation and achieved proof of concept in tumors with Hh pathway mutations. ©2011 AACR.

Hedgehog-mediated paracrine interaction between hepatic stellate cells and marrow-derived mesenchymal stem cells

International Nuclear Information System (INIS)

Lin Nan; Tang Zhaofeng; Deng Meihai; Zhong Yuesi; Lin Jizong; Yang Xuhui; Xiang Peng; Xu Ruiyun

2008-01-01

During liver injury, bone marrow-derived mesenchymal stem cells (MSCs) can migrate and differentiate into hepatocytes. Hepatic stellate cell (SC) activation is a pivotal event in the development of liver fibrosis. Therefore, we hypothesized that SCs may play an important role in regulating MSC proliferation and differentiation through the paracrine signaling pathway. We demonstrate that MSCs and SCs both express hedgehog (Hh) pathway components, including its ligands, receptors, and target genes. Transwell co-cultures of SCs and MSCs showed that the SCs produced sonic hedgehog (Shh), which enhanced the proliferation and differentiation of MSCs. These findings demonstrate that SCs indirectly modulate the activity of MSCs in vitro via the Hh pathway, and provide a plausible explanation for the mechanisms of transplanted MSCs in the treatment of liver fibrosis

The Role of Sonic Hedgehog in Craniofacial Patterning, Morphogenesis and Cranial Neural Crest Survival.

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Dworkin, Sebastian; Boglev, Yeliz; Owens, Harley; Goldie, Stephen J

2016-08-03

Craniofacial defects (CFD) are a significant healthcare problem worldwide. Understanding both the morphogenetic movements which underpin normal facial development, as well as the molecular factors which regulate these processes, forms the cornerstone of future diagnostic, and ultimately, preventative therapies. The soluble morphogen Sonic hedgehog ( Shh ), a vertebrate orthologue of Drosophila hedgehog , is a key signalling factor in the regulation of craniofacial skeleton development in vertebrates, operating within numerous tissue types in the craniofacial primordia to spatiotemporally regulate the formation of the face and jaws. This review will provide an overview of normal craniofacial skeleton development, and focus specifically on the known roles of Shh in regulating the development and progression of the first pharyngeal arch, which in turn gives rise to both the upper jaw (maxilla) and lower jaw (mandible).

The Role of Sonic Hedgehog in Craniofacial Patterning, Morphogenesis and Cranial Neural Crest Survival

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Sebastian Dworkin

2016-08-01

Full Text Available Craniofacial defects (CFD are a significant healthcare problem worldwide. Understanding both the morphogenetic movements which underpin normal facial development, as well as the molecular factors which regulate these processes, forms the cornerstone of future diagnostic, and ultimately, preventative therapies. The soluble morphogen Sonic hedgehog (Shh, a vertebrate orthologue of Drosophila hedgehog, is a key signalling factor in the regulation of craniofacial skeleton development in vertebrates, operating within numerous tissue types in the craniofacial primordia to spatiotemporally regulate the formation of the face and jaws. This review will provide an overview of normal craniofacial skeleton development, and focus specifically on the known roles of Shh in regulating the development and progression of the first pharyngeal arch, which in turn gives rise to both the upper jaw (maxilla and lower jaw (mandible.

Hedgehogs on the move: Testing the effects of land use change on home range size and movement patterns of free-ranging Ethiopian hedgehogs.

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Abu Baker, Mohammad A; Reeve, Nigel; Conkey, April A T; Macdonald, David W; Yamaguchi, Nobuyuki

2017-01-01

Degradation and alteration of natural environments because of agriculture and other land uses have major consequences on vertebrate populations, particularly on spatial organization and movement patterns. We used GPS tracking to study the effect of land use and sex on the home range size and movement of a typical model species, the Ethiopian hedgehogs. We used free-ranging hedgehogs from two areas with different land use practices: 24 from an area dominated by irrigated farms (12 ♂♂, 12 ♀♀) and 22 from a natural desert environment within a biosphere reserve (12 ♂♂, 10 ♀♀). Animals were significantly heavier in the resource-rich irrigated farms area (417.71 ±12.77SE g) in comparison to the natural desert area (376.37±12.71SE g). Both habitat and sex significantly influenced the home range size of hedgehogs. Home ranges were larger in the reserve than in the farms area. Total home ranges averaged 103 ha (±17 SE) for males and 42 ha (±11SE) for females in the farms area, but were much larger in the reserve averaging 230 ha (±33 SE) for males and 150 ha (±29 SE) for females. The home ranges of individuals of both sexes overlapped. Although females were heavier than males, body weight had no effect on home range size. The results suggest that resources provided in the farms (e.g. food, water, and shelters) influenced animal density and space use. Females aggregated around high-resource areas (either farms or rawdhats), whereas males roamed over greater distances, likely in search of mating opportunities to maximize reproductive success. Most individual home ranges overlapped with many other individuals of either sex, suggesting a non-territorial, promiscuous mating. Patterns of space use and habitat utilization are key factors in shaping aspects of reproductive biology and mating system. To minimize the impacts of agriculture on local wildlife, we recommend that biodiversity-friendly agro-environmental schemes be introduced in the Middle East where

Hedgehogs on the move: Testing the effects of land use change on home range size and movement patterns of free-ranging Ethiopian hedgehogs.

Directory of Open Access Journals (Sweden)

Mohammad A Abu Baker

Full Text Available Degradation and alteration of natural environments because of agriculture and other land uses have major consequences on vertebrate populations, particularly on spatial organization and movement patterns. We used GPS tracking to study the effect of land use and sex on the home range size and movement of a typical model species, the Ethiopian hedgehogs. We used free-ranging hedgehogs from two areas with different land use practices: 24 from an area dominated by irrigated farms (12 ♂♂, 12 ♀♀ and 22 from a natural desert environment within a biosphere reserve (12 ♂♂, 10 ♀♀. Animals were significantly heavier in the resource-rich irrigated farms area (417.71 ±12.77SE g in comparison to the natural desert area (376.37±12.71SE g. Both habitat and sex significantly influenced the home range size of hedgehogs. Home ranges were larger in the reserve than in the farms area. Total home ranges averaged 103 ha (±17 SE for males and 42 ha (±11SE for females in the farms area, but were much larger in the reserve averaging 230 ha (±33 SE for males and 150 ha (±29 SE for females. The home ranges of individuals of both sexes overlapped. Although females were heavier than males, body weight had no effect on home range size. The results suggest that resources provided in the farms (e.g. food, water, and shelters influenced animal density and space use. Females aggregated around high-resource areas (either farms or rawdhats, whereas males roamed over greater distances, likely in search of mating opportunities to maximize reproductive success. Most individual home ranges overlapped with many other individuals of either sex, suggesting a non-territorial, promiscuous mating. Patterns of space use and habitat utilization are key factors in shaping aspects of reproductive biology and mating system. To minimize the impacts of agriculture on local wildlife, we recommend that biodiversity-friendly agro-environmental schemes be introduced in the Middle

Mast cells in the sheep, hedgehog and rat forebrain

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MICHALOUDI, HELEN C.; PAPADOPOULOS, GEORGIOS C.

1999-01-01

The study was designed to reveal the distribution of various mast cell types in the forebrain of the adult sheep, hedgehog and rat. Based on their histochemical and immunocytochemical characteristics, mast cells were categorised as (1) connective tissue-type mast cells, staining metachromatically purple with the toluidine blue method, or pale red with the Alcian blue/safranin method, (2) mucosal-type or immature mast cells staining blue with the Alcian blue/safranin method and (3) serotonin immunopositive mast cells. All 3 types of brain mast cells in all species studied were located in both white and grey matter, often associated with intraparenchymal blood vessels. Their distribution pattern exhibited interspecies differences, while their number varied considerably not only between species but also between individuals of each species. A distributional left-right asymmetry, with more cells present on the left side, was observed in all species studied but it was most prominent in the sheep brain. In the sheep, mast cells were abundantly distributed in forebrain areas, while in the hedgehog and the rat forebrain, mast cells were less widely distributed and were relatively or substantially fewer in number respectively. A limited number of brain mast cells, in all 3 species, but primarily in the rat, were found to react both immunocytochemically to 5-HT antibody and histochemically with Alcian blue/safranin staining. PMID:10634696

Parvalbumin and calbindin immunoreactivity in the cerebral cortex of the hedgehog (Erinaceus europaeus).

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Ferrer, I; Zujar, M J; Admella, C; Alcantara, S

1992-01-01

To investigate the morphology and distribution of nonpyramidal neurons in the brain of insectivores, parvalbumin and calbindin 28 kDa immunoreactivity was examined in the cerebral cortex of the hedgehog (Erinaceus europaeus). Parvalbumin-immunoreactive cells were found in all layers of the isocortex, but in contrast to other mammals, a laminar organisation or specific regional distribution was not seen. Characteristic parvalbumin-immunoreactive neurons were multipolar cells with large ascending and descending dendrites extending throughout several layers. Calbindin-immunoreactive neurons were similar to those found in other species, although appearing in smaller numbers than in the cerebral cortex of more advanced mammals. The morphology and distribution of parvalbumin- and calbindin-immunoreactive cells in the piriform and entorhinal cortices were similar in hedgehogs and rodents. Parvalbumin-immunoreactive cells in the hippocampal complex were pyramidal-like and bitufted neurons, which were mainly found in the stratum oriens and stratum pyramidale of the hippocampus, and in the stratum moleculare and hilus of the fascia dentata. Heavily stained cells were found in the deep part of the stratum granulare. Intense calbindin immunoreactivity occurred mainly in the granule cell and molecular layers of the dentate gyrus and in the mossy fibre layer. The most outstanding feature in the hippocampal complex of the hedgehog was the extension of calbindin immunoreactivity to CA1 field of the hippocampus, suggesting, in agreement with other reports, that mossy fibres can establish synaptic contacts throughout the pyramidal cell layer. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 PMID:1452472

Some kinetic properties of plasma lecithin-cholesterol acyltransferase in hyper-alphalipoproteinemia in man

International Nuclear Information System (INIS)

Nikiforova, A.A.; Alksnis, E.G.; Ivanova, E.M.

1985-01-01

The aim of this investigation was to study some kinetic properties of lecithin-cholesterol acyltransferase (LCAT) in the blood plasma of patients with hyper-alpha-lipoproteinemia, enabling the presence of LCAT isozymes in the blood to be detected. The velocity of the LCAT reaction was judged by determining labeled CHE formed from 14 C-nonesterified CH and lecithin of HDL on incubation of the latter with the enzyme. Dependence of the velocity of the LCAT reaction on concentration of substrate (nonesterified HDL cholesterol) in four subjects with hyper-alpha-lipoproteinemia is shown

Hedgehog-PKA signaling and gnrh3 regulate the development of zebrafish gnrh3 neurons.

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Ming-Wei Kuo

Full Text Available GnRH neurons secrete GnRH that controls the development of the reproduction system. Despite many studies, the signals controlling the development of GnRH neurons from its progenitors have not been fully established. To understand the development of GnRH neurons, we examined the development of gnrh3-expressing cells using a transgenic zebrafish line that expresses green fluorescent protein (GFP and LacZ driven by the gnrh3 promoter. GFP and LacZ expression recapitulated that of gnrh3 in the olfactory region, olfactory bulb and telencephalon. Depletion of gnrh3 by morpholinos led to a reduction of GFP- and gnrh3-expressing cells, while over-expression of gnrh3 mRNA increased the number of these cells. This result indicates a positive feed-forward regulation of gnrh3 cells by gnrh3. The gnrh3 cells were absent in embryos that lack Hedgehog signaling, but their numbers were increased in embryos overexpressing shhb. We manipulated the amounts of kinase that antagonizes the Hedgehog signaling pathway, protein kinase A (PKA, by treating embryos with PKA activator forskolin or by injecting mRNAs encoding its constitutively active catalytic subunit (PKA* and dominant negative regulatory subunit (PKI into zebrafish embryos. PKA* misexpression or forskolin treatment decreased GFP cell numbers, while PKI misexpression led to ectopic production of GFP cells. Our data indicate that the Hedgehog-PKA pathway participates in the development of gnrh3-expressing neurons during embryogenesis.

Integrated QSAR study for inhibitors of Hedgehog Signal Pathway against multiple cell lines:a collaborative filtering method.

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Gao, Jun; Che, Dongsheng; Zheng, Vincent W; Zhu, Ruixin; Liu, Qi

2012-07-31

The Hedgehog Signaling Pathway is one of signaling pathways that are very important to embryonic development. The participation of inhibitors in the Hedgehog Signal Pathway can control cell growth and death, and searching novel inhibitors to the functioning of the pathway are in a great demand. As the matter of fact, effective inhibitors could provide efficient therapies for a wide range of malignancies, and targeting such pathway in cells represents a promising new paradigm for cell growth and death control. Current research mainly focuses on the syntheses of the inhibitors of cyclopamine derivatives, which bind specifically to the Smo protein, and can be used for cancer therapy. While quantitatively structure-activity relationship (QSAR) studies have been performed for these compounds among different cell lines, none of them have achieved acceptable results in the prediction of activity values of new compounds. In this study, we proposed a novel collaborative QSAR model for inhibitors of the Hedgehog Signaling Pathway by integration the information from multiple cell lines. Such a model is expected to substantially improve the QSAR ability from single cell lines, and provide useful clues in developing clinically effective inhibitors and modifications of parent lead compounds for target on the Hedgehog Signaling Pathway. In this study, we have presented: (1) a collaborative QSAR model, which is used to integrate information among multiple cell lines to boost the QSAR results, rather than only a single cell line QSAR modeling. Our experiments have shown that the performance of our model is significantly better than single cell line QSAR methods; and (2) an efficient feature selection strategy under such collaborative environment, which can derive the commonly important features related to the entire given cell lines, while simultaneously showing their specific contributions to a specific cell-line. Based on feature selection results, we have proposed several

The Hedgehog Inhibitor Cyclopamine Reduces β-Catenin-Tcf Transcriptional Activity, Induces E-Cadherin Expression, and Reduces Invasion in Colorectal Cancer Cells

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Qualtrough, David, E-mail: david.qualtrough@uwe.ac.uk [Department of Biological, Biomedical & Analytical Sciences, University of the West of England, Faculty of Health and Applied Sciences, University of the West of England, Frenchay, Bristol BS16 1QY (United Kingdom); Rees, Phil; Speight, Beverley; Williams, Ann C.; Paraskeva, Christos [School of Cellular & Molecular Medicine, University of Bristol, Medical Sciences Building, University Walk, Bristol BS8 1TD (United Kingdom)

2015-09-17

Colorectal cancer is a major global health problem resulting in over 600,000 deaths world-wide every year with the majority of these due to metastatic disease. Wnt signalling, and more specifically β-catenin-related transcription, has been shown to drive both tumorigenesis and the metastatic process in colorectal neoplasia, yet its complex interactions with other key signalling pathways, such as hedgehog, remain to be elucidated. We have previously shown that the Hedgehog (HH) signalling pathway is active in cells from colorectal tumours, and that inhibition of the pathway with cyclopamine induces apoptosis. We now show that cyclopamine treatment reduces β-catenin related transcription in colorectal cancer cell lines, and that this effect can be reversed by addition of Sonic Hedgehog protein. We also show that cyclopamine concomitantly induces expression of the tumour suppressor and prognostic indicator E-cadherin. Consistent with a role for HH in regulating the invasive potential we show that cyclopamine reduces the expression of transcription factors (Slug, Snail and Twist) associated with the epithelial-mesenchymal transition and reduces the invasiveness of colorectal cancer cells in vitro. Taken together, these data show that pharmacological inhibition of the hedgehog pathway has therapeutic potential in the treatment of colorectal cancer.

The Hedgehog Inhibitor Cyclopamine Reduces β-Catenin-Tcf Transcriptional Activity, Induces E-Cadherin Expression, and Reduces Invasion in Colorectal Cancer Cells

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David Qualtrough

2015-09-01

Full Text Available Colorectal cancer is a major global health problem resulting in over 600,000 deaths world-wide every year with the majority of these due to metastatic disease. Wnt signalling, and more specifically β-catenin-related transcription, has been shown to drive both tumorigenesis and the metastatic process in colorectal neoplasia, yet its complex interactions with other key signalling pathways, such as hedgehog, remain to be elucidated. We have previously shown that the Hedgehog (HH signalling pathway is active in cells from colorectal tumours, and that inhibition of the pathway with cyclopamine induces apoptosis. We now show that cyclopamine treatment reduces β-catenin related transcription in colorectal cancer cell lines, and that this effect can be reversed by addition of Sonic Hedgehog protein. We also show that cyclopamine concomitantly induces expression of the tumour suppressor and prognostic indicator E-cadherin. Consistent with a role for HH in regulating the invasive potential we show that cyclopamine reduces the expression of transcription factors (Slug, Snail and Twist associated with the epithelial-mesenchymal transition and reduces the invasiveness of colorectal cancer cells in vitro. Taken together, Cancers 2015, 7 1886 these data show that pharmacological inhibition of the hedgehog pathway has therapeutic potential in the treatment of colorectal cancer.

The Hedgehog Inhibitor Cyclopamine Reduces β-Catenin-Tcf Transcriptional Activity, Induces E-Cadherin Expression, and Reduces Invasion in Colorectal Cancer Cells

International Nuclear Information System (INIS)

Qualtrough, David; Rees, Phil; Speight, Beverley; Williams, Ann C.; Paraskeva, Christos

2015-01-01

Colorectal cancer is a major global health problem resulting in over 600,000 deaths world-wide every year with the majority of these due to metastatic disease. Wnt signalling, and more specifically β-catenin-related transcription, has been shown to drive both tumorigenesis and the metastatic process in colorectal neoplasia, yet its complex interactions with other key signalling pathways, such as hedgehog, remain to be elucidated. We have previously shown that the Hedgehog (HH) signalling pathway is active in cells from colorectal tumours, and that inhibition of the pathway with cyclopamine induces apoptosis. We now show that cyclopamine treatment reduces β-catenin related transcription in colorectal cancer cell lines, and that this effect can be reversed by addition of Sonic Hedgehog protein. We also show that cyclopamine concomitantly induces expression of the tumour suppressor and prognostic indicator E-cadherin. Consistent with a role for HH in regulating the invasive potential we show that cyclopamine reduces the expression of transcription factors (Slug, Snail and Twist) associated with the epithelial-mesenchymal transition and reduces the invasiveness of colorectal cancer cells in vitro. Taken together, these data show that pharmacological inhibition of the hedgehog pathway has therapeutic potential in the treatment of colorectal cancer

Catecholaminergic and serotoninergic fibres innervate the ventricular system of the hedgehog CNS.

Science.gov (United States)

Michaloudi, H C; Papadopoulos, G C

1996-01-01

Immunocytochemistry with antisera against serotonin (5-HT), dopamine (DA) and noradrenaline (NA) was used to detect monoaminergic (MA) fibres in the ventricular system of the hedgehog Erinaceus europaeus. Light microscopic examination of immunocytochemically stained sections revealed that the ventricular system of the hedgehog is unique among mammals in that the choroid plexuses receive CA axons and that the supraependyma and subependyma of the cerebral ventricles and the spinal central canal are innervated both by serotoninergic and catecholaminergic (CA) fibres. Supraependymal 5-HT axons were generally more abundant and created at places a large number of interconnected basket-like structures, whereas CA fibres were usually directed towards the ventricular lumen. In the lateral ventricles, CA fibres were more numerous in the ependyma lining grey matter, whereas a higher 5-HT innervation density was observed in the area between the corpus callosum and the caudate nucleus or the septum. In the 3rd ventricle, the ependyma of its dorsal part exhibited a higher 5-HT and NA innervation density, whereas DA fibres were preferentially distributed in the ventral half of the basal region. The ependyma lining the cerebral aqueduct displayed a higher MA innervation density in its ventral part. The ependymal wall of the 4th ventricle exhibited an extremely dense 5-HT innervation, mainly in the floor of the ventricle, relatively fewer NA fibres and only sparse DA ones. Few NA and relatively more 5-HT fibres were detected in the ependyma of the central canal. Finally, the circumventricular organs were unevenly innervated by the 3 types of MA fibres. The extensive monoaminergic innervation of the hedgehog ventricular system described here probably reflects a transitory evolutionary stage in the phylogeny of the MA systems with presently unknown functional implications. Images Fig. 1 Fig. 2 Figs 3-8 Figs 9-14 Figs 15-20 PMID:8886949

Multicentric epitheliotropic T-cell lymphoma in an African hedgehog (Atelerix albiventris).

Science.gov (United States)

Chung, Tae-Ho; Kim, Hyo-Jin; Choi, Ul-Soo

2014-12-01

A 2-year-old female African hedgehog was presented with a 5-month history of pruritus, and diffuse spine and hair loss. A dermatologic examination revealed erythema, excoriation, scales, and crusting affecting the face, flanks, forelimbs, hindlimbs, and dorsal and ventral abdomen. Fine-needle aspiration was performed and skin biopsies were taken from several lesions for cytologic and histologic evaluation. The aspirates yielded smears characterized by a monomorphic population of medium-sized to large lymphocytes with scant to moderate amounts of clear to moderately basophilic cytoplasm and distinct nucleoli along with a low number of cytoplasmic fragments. On histopathologic examination, there were dense dermal lymphoid infiltrates invading the dermis and a monomorphic population of round cells that had infiltrated the overlying epidermis. Epitheliotropic cutaneous lymphoma was diagnosed based on morphologic features. Additional immunochemical analysis using anti-CD3 and anti-CD79a antibodies revealed strong CD3 expression by the tumor cells, which confirmed epitheliotropic cutaneous T-cell lymphoma. This is the first description of a multicentric pattern of epitheliotropic cutaneous T-cell lymphoma in an African hedgehog. © 2014 American Society for Veterinary Clinical Pathology.

Five-dimensional Monopole Equation with Hedge-Hog Ansatz and Abel's Differential Equation

OpenAIRE

Kihara, Hironobu

2008-01-01

We review the generalized monopole in the five-dimensional Euclidean space. A numerical solution with the Hedge-Hog ansatz is studied. The Bogomol'nyi equation becomes a second order autonomous non-linear differential equation. The equation can be translated into the Abel's differential equation of the second kind and is an algebraic differential equation.

Dispatched and scube mediate the efficient secretion of the cholesterol-modified hedgehog ligand.

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Tukachinsky, Hanna; Kuzmickas, Ryan P; Jao, Cindy Y; Liu, Jing; Salic, Adrian

2012-08-30

The Hedgehog (Hh) signaling pathway plays critical roles in metazoan development and in cancer. How the Hh ligand is secreted and spreads to distant cells is unclear, given its covalent modification with a hydrophobic cholesterol molecule, which makes it stick to membranes. We demonstrate that Hh ligand secretion from vertebrate cells is accomplished via two distinct and synergistic cholesterol-dependent binding events, mediated by two proteins that are essential for vertebrate Hh signaling: the membrane protein Dispatched (Disp) and a member of the Scube family of secreted proteins. Cholesterol modification is sufficient for a heterologous protein to interact with Scube and to be secreted in a Scube-dependent manner. Disp and Scube recognize different structural aspects of cholesterol similarly to how Niemann-Pick disease proteins 1 and 2 interact with cholesterol, suggesting a hand-off mechanism for transferring Hh from Disp to Scube. Thus, Disp and Scube cooperate to dramatically enhance the secretion and solubility of the cholesterol-modified Hh ligand. Copyright © 2012 The Authors. Published by Elsevier Inc. All rights reserved.

Deletion of 1 amino acid in Indian hedgehog leads to brachydactylyA1

NARCIS (Netherlands)

Lodder, E. M.; Hoogeboom, A. J. M.; Coert, J. H.; de Graaff, E.

2008-01-01

Brachydactyly type A1 is a limb malformation characterized by a uniform shortening of the middle phalanges in all digits. Mutations in the Indian hedgehog (IHH) gene were shown to be the cause of this autosomal dominant disorder. The IHH protein is known to be an important signaling molecule

Discovery of a novel series of benzimidazole derivatives as diacylglycerol acyltransferase inhibitors.

Science.gov (United States)

Lee, Kyeong; Goo, Ja-Il; Jung, Hwa Young; Kim, Minkyoung; Boovanahalli, Shanthaveerappa K; Park, Hye Ran; Kim, Mun-Ock; Kim, Dong-Hyun; Lee, Hyun Sun; Choi, Yongseok

2012-12-15

A novel series of benzimidazole derivatives was prepared and evaluated for their diacylglycerol acyltransferase (DGAT) inhibitory activity using microsome from rat liver. Among the newly synthesized compounds, furfurylamine containing benzimidazole carboxamide 10j showed the most potent DGAT inhibitory effect (IC(50)=4.4 μM) and inhibited triglyceride formation in HepG2 cells. Furthermore, compound 10j reduced body weight gain of Institute of Cancer Research mice on a high-fat diet and decreased levels of total triglyceride, total cholesterol, and LDL-cholesterol in the blood accompanied with a significant increase in HDL-cholesterol level. Copyright © 2012 Elsevier Ltd. All rights reserved.

Signaling domain of Sonic Hedgehog as cannibalistic calcium-regulated zinc-peptidase.

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Rocio Rebollido-Rios

2014-07-01

Full Text Available Sonic Hedgehog (Shh is a representative of the evolutionary closely related class of Hedgehog proteins that have essential signaling functions in animal development. The N-terminal domain (ShhN is also assigned to the group of LAS proteins (LAS = Lysostaphin type enzymes, D-Ala-D-Ala metalloproteases, Sonic Hedgehog, of which all members harbor a structurally well-defined Zn2+ center; however, it is remarkable that ShhN so far is the only LAS member without proven peptidase activity. Another unique feature of ShhN in the LAS group is a double-Ca2+ center close to the zinc. We have studied the effect of these calcium ions on ShhN structure, dynamics, and interactions. We find that the presence of calcium has a marked impact on ShhN properties, with the two calcium ions having different effects. The more strongly bound calcium ion significantly stabilizes the overall structure. Surprisingly, the binding of the second calcium ion switches the putative catalytic center from a state similar to LAS enzymes to a state that probably is catalytically inactive. We describe in detail the mechanics of the switch, including the effect on substrate co-ordinating residues and on the putative catalytic water molecule. The properties of the putative substrate binding site suggest that ShhN could degrade other ShhN molecules, e.g. by cleavage at highly conserved glycines in ShhN. To test experimentally the stability of ShhN against autodegradation, we compare two ShhN mutants in vitro: (1 a ShhN mutant unable to bind calcium but with putative catalytic center intact, and thus, according to our hypothesis, a constitutively active peptidase, and (2 a mutant carrying additionally mutation E177A, i.e., with the putative catalytically active residue knocked out. The in vitro results are consistent with ShhN being a cannibalistic zinc-peptidase. These experiments also reveal that the peptidase activity depends on pH.

Human germline hedgehog pathway mutations predispose to fatty liver.

Science.gov (United States)

Guillen-Sacoto, Maria J; Martinez, Ariel F; Abe, Yu; Kruszka, Paul; Weiss, Karin; Everson, Joshua L; Bataller, Ramon; Kleiner, David E; Ward, Jerrold M; Sulik, Kathleen K; Lipinski, Robert J; Solomon, Benjamin D; Muenke, Maximilian

2017-10-01

Non-alcoholic fatty liver disease (NAFLD) is the most common form of liver disease. Activation of hedgehog (Hh) signaling has been implicated in the progression of NAFLD and proposed as a therapeutic target; however, the effects of Hh signaling inhibition have not been studied in humans with germline mutations that affect this pathway. Patients with holoprosencephaly (HPE), a disorder associated with germline mutations disrupting Sonic hedgehog (SHH) signaling, were clinically evaluated for NAFLD. A combined mouse model of Hh signaling attenuation (Gli2 heterozygous null: Gli2 +/- ) and diet-induced NAFLD was used to examine aspects of NAFLD and hepatic gene expression profiles, including molecular markers of hepatic fibrosis and inflammation. Patients with HPE had a higher prevalence of liver steatosis compared to the general population, independent of obesity. Exposure of Gli2 +/- mice to fatty liver-inducing diets resulted in increased liver steatosis compared to wild-type mice. Similar to humans, this effect was independent of obesity in the mutant mice and was associated with decreased expression of pro-fibrotic and pro-inflammatory genes, and increased expression of PPARγ, a potent anti-fibrogenic and anti-inflammatory regulator. Interestingly, tumor suppressors p53 and p16INK4 were found to be downregulated in the Gli2 +/- mice exposed to a high-fat diet. Our results indicate that germline mutations disrupting Hh signaling promotes liver steatosis, independent of obesity, with reduced fibrosis. While Hh signaling inhibition has been associated with a better NAFLD prognosis, further studies are required to evaluate the long-term effects of mutations affecting this pathway. Lay summary: Non-alcoholic fatty liver disease (NAFLD) is characterized by excess fat deposition in the liver predominantly due to high calorie intake and a sedentary lifestyle. NAFLD progression is usually accompanied by activation of the Sonic hedgehog (SHH) pathway leading to fibrous

Life on the edge : hedgehog traffic victims and mitigation strategies in an anthropogenic landscape

NARCIS (Netherlands)

Huijser, M.P.

2000-01-01

This study focused on the most frequently recorded mammal species in road-kill surveys in western Europe: the hedgehog (Erinaceus europaeus). Investigations were conducted in an anthropogenic landscape and had two major aims:

1. to quantify the effects of traffic

2. Morphology, histochemistry and glycosylation of the placenta and associated tissues in the European hedgehog (Erinaceus europaeus)

   DEFF Research Database (Denmark)

   Jones, Carolyn J P; Carter, A M; Allen, W R

   2016-01-01

   glycosylated. Yolk sac inner and outer endoderm expressed similar glycans except for N-acetylgalactosamine residues in endodermal acini. DISCUSSION: New features of near-term hedgehog placenta and associated tissues are presented, including their glycosylation, and novel yolk sac acinar structures......INTRODUCTION: There are few descriptions of the placenta and associated tissues of the European hedgehog (Erinaceus europaeus) and here we present findings on a near-term pregnant specimen. METHODS: Tissues were examined grossly and then formalin fixed and wax-embedded for histology...... and immunocytochemistry (cytokeratin) and resin embedded for lectin histochemistry. RESULTS: Each of four well-developed and near term hoglets displayed a discoid, haemochorial placenta with typical labyrinth and spongy zones. In addition there was a paraplacenta incorporating Reichert's membrane and a largely detached...

3. Hedgehog pathway mediates early acceleration of liver regeneration induced by a novel two-staged hepatectomy in mice.

   Science.gov (United States)

   Langiewicz, Magda; Schlegel, Andrea; Saponara, Enrica; Linecker, Michael; Borger, Pieter; Graf, Rolf; Humar, Bostjan; Clavien, Pierre A

   2017-03-01

   ALPPS, a novel two-staged approach for the surgical removal of large/multiple liver tumors, combines portal vein ligation (PVL) with parenchymal transection. This causes acceleration of compensatory liver growth, enabling faster and more extensive tumor removal. We sought to identify the plasma factors thought to mediate the regenerative acceleration following ALPPS. We compared a mouse model of ALPPS against PVL and additional control surgeries (n=6 per group). RNA deep sequencing was performed to identify candidate molecules unique to ALPPS liver (n=3 per group). Recombinant protein and a neutralizing antibody combined with appropriate surgeries were used to explore candidate functions in ALPPS (n=6 per group). Indian hedgehog (IHH/Ihh) levels were assessed in human ALPPS patient plasma (n=6). ALPPS in mouse confirmed significant acceleration of liver regeneration relative to PVL (pIhh mRNA, coding for a secreted ligand inducing hedgehog signaling, was uniquely upregulated in ALPPS liver (pIhh plasma levels rose 4h after surgery (pIhh alone was sufficient to induce ALPPS-like acceleration of liver growth. Conversely, blocking Ihh markedly inhibited the accelerating effects of ALPPS. In the small cohort of ALPPS patients, IHH tended to be elevated early after surgery. Ihh and hedgehog pathway activation provide the first mechanistic insight into the acceleration of liver regeneration triggered by ALPPS surgery. The accelerating potency of recombinant Ihh, and its potential effect in human ALPPS may lead to a clinical role for this protein. ALPPS, a novel two-staged hepatectomy, accelerates liver regeneration, thereby helping to treat patients with otherwise unresectable liver tumors. The molecular mechanisms behind this accelerated regeneration are unknown. Here, we elucidate that Indian hedgehog, a secreted ligand important for fetal development, is a crucial mediator of the regenerative acceleration triggered by ALPPS surgery. Copyright © 2016. Published by

4. Hedgehog signaling is required for formation of the notochord sheath and patterning of nuclei pulposi within the intervertebral discs.

   Science.gov (United States)

   Choi, Kyung-Suk; Harfe, Brian D

   2011-06-07

   The vertebrae notochord is a transient rod-like structure that produces secreted factors that are responsible for patterning surrounding tissues. During later mouse embryogenesis, the notochord gives rise to the middle part of the intervertebral disc, called the nucleus pulposus. Currently, very little is known about the molecular mechanisms responsible for forming the intervertebral discs. Here we demonstrate that hedgehog signaling is required for formation of the intervertebral discs. Removal of hedgehog signaling in the notochord and nearby floorplate resulted in the formation of an aberrant notochord sheath that normally surrounds this structure. In the absence of the notochord sheath, small nuclei pulposi were formed, with most notochord cells dispersed throughout the vertebral bodies during embryogenesis. Our data suggest that the formation of the notochord sheath requires hedgehog signaling and that the sheath is essential for maintaining the rod-like structure of the notochord during early embryonic development. As notochord cells form nuclei pulposi, we propose that the notochord sheath functions as a "wrapper" around the notochord to constrain these cells along the vertebral column.

5. SLC1 and SLC4 encode partially redundant acyl-coenzyme A 1-acylglycerol-3-phosphate O-acyltransferases of budding yeast

   DEFF Research Database (Denmark)

   Benghezal, Mohammed; Roubaty, Carole; Veepuri, Vijayanath

   2007-01-01

   Phosphatidic acid is the intermediate, from which all glycerophospholipids are synthesized. In yeast, it is generated from lysophosphatidic acid, which is acylated by Slc1p, an sn-2-specific, acyl-coenzyme A-dependent 1-acylglycerol-3-phosphate O-acyltransferase. Deletion of SLC1 is not lethal...

6. Discovery and Optimization of Imidazopyridine-Based Inhibitors of Diacylglycerol Acyltransferase 2 (DGAT2).

   Science.gov (United States)

   Futatsugi, Kentaro; Kung, Daniel W; Orr, Suvi T M; Cabral, Shawn; Hepworth, David; Aspnes, Gary; Bader, Scott; Bian, Jianwei; Boehm, Markus; Carpino, Philip A; Coffey, Steven B; Dowling, Matthew S; Herr, Michael; Jiao, Wenhua; Lavergne, Sophie Y; Li, Qifang; Clark, Ronald W; Erion, Derek M; Kou, Kou; Lee, Kyuha; Pabst, Brandon A; Perez, Sylvie M; Purkal, Julie; Jorgensen, Csilla C; Goosen, Theunis C; Gosset, James R; Niosi, Mark; Pettersen, John C; Pfefferkorn, Jeffrey A; Ahn, Kay; Goodwin, Bryan

   2015-09-24

   The medicinal chemistry and preclinical biology of imidazopyridine-based inhibitors of diacylglycerol acyltransferase 2 (DGAT2) is described. A screening hit 1 with low lipophilic efficiency (LipE) was optimized through two key structural modifications: (1) identification of the pyrrolidine amide group for a significant LipE improvement, and (2) insertion of a sp(3)-hybridized carbon center in the core of the molecule for simultaneous improvement of N-glucuronidation metabolic liability and off-target pharmacology. The preclinical candidate 9 (PF-06424439) demonstrated excellent ADMET properties and decreased circulating and hepatic lipids when orally administered to dyslipidemic rodent models.

7. Research advances in Hedgehog signaling pathway in hepatocellular carcinoma

   Directory of Open Access Journals (Sweden)

   LIU Jia

   2015-02-01

   Full Text Available Hedgehog (Hh signaling pathway is present in many animals and plays an important role in regulating embryonic development and differentiation. Aberrant activation of Hh signaling contributes to the pathogenesis of many malignancies. Recent studies have shown that dysregulated Hh signaling pathway participates in the tumorigenesis, tumor invasion, and metastasis of hepatocellular carcinoma (HCC. Investigation of the relationship between Hh signaling pathway and HCC will help elucidate the molecular mechanism of pathogenesis of HCC and provide a new insight into the development of novel anticancer therapy and therapeutic target.

8. Effect of growth hormone replacement therapy on plasma lecithin : cholesterol acyltransferase and lipid transfer protein activities in growth hormone-deficient adults

   NARCIS (Netherlands)

   Beentjes, JAM; van Tol, A; Sluiter, WJ; Dullaart, RPF

   The effects of growth hormone (GH) replacement on plasma lecithin:cholesterol acyltransferase (LCAT), cholesteryl ester transfer protein (CETP), and phospholipid transfer protein (PLTP), factors involved in high density lipoprotein (HDL) metabolism, We unknown. We carried out a 6 mouths study in 24

9. Motile cilia of human airway epithelia contain hedgehog signaling components that mediate noncanonical hedgehog signaling.

   Science.gov (United States)

   Mao, Suifang; Shah, Alok S; Moninger, Thomas O; Ostedgaard, Lynda S; Lu, Lin; Tang, Xiao Xiao; Thornell, Ian M; Reznikov, Leah R; Ernst, Sarah E; Karp, Philip H; Tan, Ping; Keshavjee, Shaf; Abou Alaiwa, Mahmoud H; Welsh, Michael J

   2018-02-06

   Differentiated airway epithelia produce sonic hedgehog (SHH), which is found in the thin layer of liquid covering the airway surface. Although previous studies showed that vertebrate HH signaling requires primary cilia, as airway epithelia mature, the cells lose primary cilia and produce hundreds of motile cilia. Thus, whether airway epithelia have apical receptors for SHH has remained unknown. We discovered that motile cilia on airway epithelial cells have HH signaling proteins, including patched and smoothened. These cilia also have proteins affecting cAMP-dependent signaling, including Gα i and adenylyl cyclase 5/6. Apical SHH decreases intracellular levels of cAMP, which reduces ciliary beat frequency and pH in airway surface liquid. These results suggest that apical SHH may mediate noncanonical HH signaling through motile cilia to dampen respiratory defenses at the contact point between the environment and the lung, perhaps counterbalancing processes that stimulate airway defenses. Copyright © 2018 the Author(s). Published by PNAS.

10. Hedgehog Protein Cholesterolysis: A New Therapeutic Target for Advanced Prostate Cancer

    Science.gov (United States)

    2016-10-01

    cholesterolysis, the oncogenic Hh polypeptide is generated through a peptide cleavage reaction involving cholesterol. Cholesterolysis represents an...ligand, HhN, is released from this precursor by peptide bond cholesterolysis, a cleavage/lipidation event unique to the Hh family[4] (Figure 1A...substrate activity of A and G through sec- ondary assays involving a chimeric Hh precursor, where the human sonic hedgehog ligand (20 kDa) is fused to the

11. Niemann-Pick C1-deficient mice lacking sterol O-acyltransferase 2 have less hepatic cholesterol entrapment and improved liver function.

    Science.gov (United States)

    Lopez, Adam M; Jones, Ryan Dale; Repa, Joyce J; Turley, Stephen D

    2018-06-07

    Cholesteryl esters are generated at multiple sites in the body by sterol O-acyltransferase 1 (SOAT1) or sterol O-acyltransferase 2 (SOAT2) in various cell types, and lecithin cholesterol acyltransferase (LCAT) in plasma. Esterified cholesterol (EC) and triacylglycerol (TAG) contained in lipoproteins cleared from the circulation via receptor-mediated or bulk-phase endocytosis are hydrolyzed by lysosomal acid lipase (LAL) within the late endosomal/lysosomal (E/L) compartment. Then, through the successive actions of Niemann-Pick C2 (NPC2) and Niemann-Pick C1 (NPC1), unesterified cholesterol (UC) is exported from the E/L compartment to the cytosol. Mutations in either NPC1 or NPC2 lead to continuing entrapment of UC in all organs, resulting in multisystem disease which includes hepatic dysfunction and in some cases liver failure. These studies investigated primarily whether elimination of SOAT2 in NPC1-deficient mice impacted hepatic UC sequestration, inflammation, and transaminase activities. Measurements were made in 7 wk-old mice fed a low-cholesterol chow diet or one enriched with cholesterol starting 2 wk before study. In the chow-fed mice, NPC1:SOAT2 double knockouts, compared to their littermates lacking only NPC1, had 20% less liver mass, 28% lower hepatic UC concentrations, and plasma ALT and AST activities that were decreased by 48% and 36%, respectively. mRNA expression levels for several markers of inflammation were all significantly lower in the NPC1 mutants lacking SOAT2. The existence of a new class of potent and selective SOAT2 inhibitors provides an opportunity for exploring if suppression of this enzyme could potentially become an adjunctive therapy for liver disease in NPC1 deficiency.

Indian Hedgehog Controls Proliferation and Differentiation in Skin Tumorigenesis and Protects against Malignant Progression

Directory of Open Access Journals (Sweden)

Parisa Kakanj

2013-07-01

Full Text Available Mutations in the hedgehog pathway drive the formation of tumors in many different organs, including the development of basal cell carcinoma in the skin. However, little is known about the role of epidermal Indian hedgehog (Ihh in skin physiology. Using mouse genetics, we identified overlapping and distinct functions of Ihh in different models of epidermal tumorigenesis. Epidermal deletion of Ihh resulted in increased formation of benign squamous papilloma. Strikingly, Ihh-deficient mice showed an increase in malignant squamous cell carcinoma and developed lung and lymph node metastases. In a sebaceous gland tumor model, Ihh deficiency inhibited tumor cell differentiation. More mechanistically, IHH stimulated cell proliferation by activating the transcription factor GLI2 in human keratinocytes and human tumors. Thus, our results uncover important functions for Ihh signaling in controlling proliferation, differentiation, malignant progression, and metastasis of epithelial cancer, establishing Ihh as a gatekeeper for controlling the grade of tumor malignancy.

Sonic Hedgehog Signaling Regulates Hematopoietic Stem/Progenitor Cell Activation during the Granulopoietic Response to Systemic Bacterial Infection.

Science.gov (United States)

Shi, Xin; Wei, Shengcai; Simms, Kevin J; Cumpston, Devan N; Ewing, Thomas J; Zhang, Ping

2018-01-01

Activation and reprogramming of hematopoietic stem/progenitor cells play a critical role in the granulopoietic response to bacterial infection. Our current study determined the significance of Sonic hedgehog (SHH) signaling in the regulation of hematopoietic precursor cell activity during the host defense response to systemic bacterial infection. Bacteremia was induced in male Balb/c mice via intravenous injection (i.v.) of Escherichia coli (5 × 10 7 CFUs/mouse). Control mice received i.v. saline. SHH protein level in bone marrow cell (BMC) lysates was markedly increased at both 24 and 48 h of bacteremia. By contrast, the amount of soluble SHH ligand in marrow elutes was significantly reduced. These contrasting alterations suggested that SHH ligand release from BMCs was reduced and/or binding of soluble SHH ligand to BMCs was enhanced. At both 12 and 24 h of bacteremia, SHH mRNA expression by BMCs was significantly upregulated. This upregulation of SHH mRNA expression was followed by a marked increase in SHH protein expression in BMCs. Activation of the ERK1/2-SP1 pathway was involved in mediating the upregulation of SHH gene expression. The major cell type showing the enhancement of SHH expression in the bone marrow was lineage positive cells. Gli1 positioned downstream of the SHH receptor activation serves as a key component of the hedgehog (HH) pathway. Primitive hematopoietic precursor cells exhibited the highest level of baseline Gli1 expression, suggesting that they were active cells responding to SHH ligand stimulation. Along with the increased expression of SHH in the bone marrow, expression of Gli1 by marrow cells was significantly upregulated at both mRNA and protein levels following bacteremia. This enhancement of Gli1 expression was correlated with activation of hematopoietic stem/progenitor cell proliferation. Mice with Gli1 gene deletion showed attenuation in activation of marrow hematopoietic stem/progenitor cell proliferation and inhibition

An acyltransferase gene that putatively functions in anthocyanin modification was horizontally transferred from Fabaceae into the genus Cuscuta

Directory of Open Access Journals (Sweden)

Ting Sun

2016-06-01

Full Text Available Horizontal gene transfer (HGT refers to the flow of genetic materials to non-offspring, and occasionally HGT in plants can improve the adaptation of organisms in new niches due to expanded metabolic capability. Anthocyanins are an important group of water-soluble red, purple, or blue secondary metabolites, whose diversity results from modification after the main skeleton biosynthesis. Cuscuta is a stem holoparasitic genus, whose members form direct connection with hosts to withdraw water, nutrients, and macromolecules. Such intimate association is thought to increase the frequency of HGT. By transcriptome screening for foreign genes in Cuscuta australis, we discovered that one gene encoding a putative anthocyanin acyltransferase gene of the BAHD family, which is likely to be involved in anthocyanin modification, was acquired by C. australis from Fabaceae through HGT. The anthocyanin acyltransferase-like (AT-like gene was confirmed to be present in the genome assembly of C. australis and the transcriptomes of Cuscuta pentagona. The higher transcriptional level in old stems is consistent with its putative function in secondary metabolism by stabilizing anthocyanin at neutral pH and thus HGT of this AT-like gene may have improved biotic and abiotic resistance of Cuscuta.

Endogenous stem cell proliferation induced by intravenous hedgehog agonist administration after contusion in the adult rat spinal cord.

Science.gov (United States)

Bambakidis, Nicholas C; Horn, Eric M; Nakaji, Peter; Theodore, Nicholas; Bless, Elizabeth; Dellovade, Tammy; Ma, Chiyuan; Wang, Xukui; Preul, Mark C; Coons, Stephen W; Spetzler, Robert F; Sonntag, Volker K H

2009-02-01

Sonic hedgehog (Shh) is a glycoprotein molecule that upregulates the transcription factor Gli1. The Shh protein plays a critical role in the proliferation of endogenous neural precursor cells when directly injected into the spinal cord after a spinal cord injury in adult rodents. Small-molecule agonists of the hedgehog (Hh) pathway were used in an attempt to reproduce these findings through intravenous administration. The expression of Gli1 was measured in rat spinal cord after the intravenous administration of an Hh agonist. Ten adult rats received a moderate contusion and were treated with either an Hh agonist (10 mg/kg, intravenously) or vehicle (5 rodents per group) 1 hour and 4 days after injury. The rats were killed 5 days postinjury. Tissue samples were immediately placed in fixative. Samples were immunohistochemically stained for neural precursor cells, and these cells were counted. Systemic dosing with an Hh agonist significantly upregulated Gli1 expression in the spinal cord (p < 0.005). After spinal contusion, animals treated with the Hh agonist had significantly more nestin-positive neural precursor cells around the rim of the lesion cavity than in vehicle-treated controls (means +/- SDs, 46.9 +/- 12.9 vs 20.9 +/- 8.3 cells/hpf, respectively, p < 0.005). There was no significant difference in the area of white matter injury between the groups. An intravenous Hh agonist at doses that upregulate spinal cord Gli1 transcription also increases the population of neural precursor cells after spinal cord injury in adult rats. These data support previous findings based on injections of Shh protein directly into the spinal cord.

Development of a monoclonal antibody-based ELISA for the hedgehog inhibitors cyclopamine and cyclopamine-KAAD

Science.gov (United States)

Cyclopamine was isolated from Veratrum californicum and identified as the teratogen responsible for severe craniofacial birth defects including cyclops in the offspring of sheep grazing on mountain ranges in central Idaho. More recently, cyclopamine was found to inhibit the hedgehog (Hh) signaling ...

TSC1 and TSC2 regulate cilia length and canonical Hedgehog signaling via different mechanisms

DEFF Research Database (Denmark)

Rosengren, Thomas; Larsen, Lasse Jonsgaard; Pedersen, Lotte Bang

2018-01-01

Primary cilia are sensory organelles that coordinate multiple cellular signaling pathways, including Hedgehog (HH), Wingless/Int (WNT) and Transforming Growth Factor-β (TGF-β) signaling. Similarly, primary cilia have been implicated in regulation of mTOR signaling, in which Tuberous Sclerosis Com...

[Life cycle of Gongylonema mucronatum Seurat, 1916, parasite of the African hedge-hog (author's transl)].

Science.gov (United States)

Quentin, J C; Seguignes, M

1979-01-01

The Gongylonematid Nematode parasite of the Tunisian hedge-hog has been identified as Gongylonema mucronatum Seurat, 1916. The infective larva has been obtained from Locusta migratoria as intermediate host. The larval characters of this Gongylonema link it to the species G. pulchrum.

Reduced primary cilia length and altered Arl13b expression are associated with deregulated chondrocyte Hedgehog signaling in alkaptonuria.

Science.gov (United States)

Thorpe, Stephen D; Gambassi, Silvia; Thompson, Clare L; Chandrakumar, Charmilie; Santucci, Annalisa; Knight, Martin M

2017-09-01

Alkaptonuria (AKU) is a rare inherited disease resulting from a deficiency of the enzyme homogentisate 1,2-dioxygenase which leads to the accumulation of homogentisic acid (HGA). AKU is characterized by severe cartilage degeneration, similar to that observed in osteoarthritis. Previous studies suggest that AKU is associated with alterations in cytoskeletal organization which could modulate primary cilia structure/function. This study investigated whether AKU is associated with changes in chondrocyte primary cilia and associated Hedgehog signaling which mediates cartilage degradation in osteoarthritis. Human articular chondrocytes were obtained from healthy and AKU donors. Additionally, healthy chondrocytes were treated with HGA to replicate AKU pathology (+HGA). Diseased cells exhibited shorter cilia with length reductions of 36% and 16% in AKU and +HGA chondrocytes respectively, when compared to healthy controls. Both AKU and +HGA chondrocytes demonstrated disruption of the usual cilia length regulation by actin contractility. Furthermore, the proportion of cilia with axoneme breaks and bulbous tips was increased in AKU chondrocytes consistent with defective regulation of ciliary trafficking. Distribution of the Hedgehog-related protein Arl13b along the ciliary axoneme was altered such that its localization was increased at the distal tip in AKU and +HGA chondrocytes. These changes in cilia structure/trafficking in AKU and +HGA chondrocytes were associated with a complete inability to activate Hedgehog signaling in response to exogenous ligand. Thus, we suggest that altered responsiveness to Hedgehog, as a consequence of cilia dysfunction, may be a contributing factor in the development of arthropathy highlighting the cilium as a novel target in AKU. © 2017 The Authors. Journal of Cellular Physiology Published by Wiley Periodicals Inc.

Anticancer drugs and the regulation of Hedgehog genes GLI1 and PTCH1, a comparative study in nonmelanoma skin cancer cell lines

DEFF Research Database (Denmark)

Olesen, Uffe H; Bojesen, Sophie; Gehl, Julie

2017-01-01

Nonmelanoma skin cancer is the most common cancer in humans, comprising mainly basal cell carcinoma (BCC) and squamous cell carcinoma (SCC). BCC proliferation is highly dependent on the Hedgehog signaling pathway. We aimed to investigate a panel of anticancer drugs with known activity against skin...... of immortalized keratinocytes (HaCaT), BCC (UWBCC1 and BCC77015), and SCC (A431 and SCC25) cell lines. The impact of treatment on the regulation of Hedgehog pathway target genes (GLI1 and PTCH1), measured by real-time PCR, was compared between UWBCC1 and HaCaT. Varying cell line sensitivity profiles...... to the examined anticancer drugs were observed. Generally, 24-h drug exposure was sufficient to reduce cell viability. We found that 5-FU, MTX, and cisplatin significantly downregulated the expression of two genes controlled by the Hedgehog pathway (≤25-, 2.9-, and 12.5-fold, respectively, for GLI1 in UWBCC1...

Comprehensive analysis of gene expression patterns of hedgehog-related genes

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Baillie David

2006-10-01

Full Text Available Abstract Background The Caenorhabditis elegans genome encodes ten proteins that share sequence similarity with the Hedgehog signaling molecule through their C-terminal autoprocessing Hint/Hog domain. These proteins contain novel N-terminal domains, and C. elegans encodes dozens of additional proteins containing only these N-terminal domains. These gene families are called warthog, groundhog, ground-like and quahog, collectively called hedgehog (hh-related genes. Previously, the expression pattern of seventeen genes was examined, which showed that they are primarily expressed in the ectoderm. Results With the completion of the C. elegans genome sequence in November 2002, we reexamined and identified 61 hh-related ORFs. Further, we identified 49 hh-related ORFs in C. briggsae. ORF analysis revealed that 30% of the genes still had errors in their predictions and we improved these predictions here. We performed a comprehensive expression analysis using GFP fusions of the putative intergenic regulatory sequence with one or two transgenic lines for most genes. The hh-related genes are expressed in one or a few of the following tissues: hypodermis, seam cells, excretory duct and pore cells, vulval epithelial cells, rectal epithelial cells, pharyngeal muscle or marginal cells, arcade cells, support cells of sensory organs, and neuronal cells. Using time-lapse recordings, we discovered that some hh-related genes are expressed in a cyclical fashion in phase with molting during larval development. We also generated several translational GFP fusions, but they did not show any subcellular localization. In addition, we also studied the expression patterns of two genes with similarity to Drosophila frizzled, T23D8.1 and F27E11.3A, and the ortholog of the Drosophila gene dally-like, gpn-1, which is a heparan sulfate proteoglycan. The two frizzled homologs are expressed in a few neurons in the head, and gpn-1 is expressed in the pharynx. Finally, we compare the

Growth of limb muscle is dependent on skeletal-derived Indian hedgehog

OpenAIRE

Bren-Mattison, Yvette; Hausburg, Melissa; Olwin, Bradley B.

2011-01-01

During embryogenesis, muscle and bone develop in close temporal and spatial proximity. We show that Indian Hedgehog, a bone-derived signaling molecule, participates in growth of skeletal muscle. In Ihh−/− embryos, skeletal muscle development appears abnormal at embryonic day 14.5 and at later ages through embryonic day 20.5, dramatic losses of hindlimb muscle occur. To further examine the role of Ihh in myogenesis, we manipulated Ihh expression in the developing chick hindlimb. Reduction of I...

Immunohistochemical analysis of Sonic hedgehog signalling in normal human urinary tract development

OpenAIRE

Jenkins, Dagan; Winyard, Paul J D; Woolf, Adrian S.

2007-01-01

Studies of mouse mutants have demonstrated that Sonic hedgehog (SHH) signalling has a functional role in morphogenesis and differentiation at multiple sites within the forming urinary tract, and urinary tract malformations have been reported in humans with mutations that disrupt SHH signalling. However, there is only strikingly sparse and fragmentary information about the expression of SHH and associated signalling genes in normal human urinary tract development. We used immunohistochemistry ...

The Role of Hedgehog-Interacting Protein in Maintaining Cavernous Nerve Integrity and Adult Penile Morphology

Science.gov (United States)

Angeloni, Nicholas L.; Bond, Christopher W.; Monsivais, Diana; Tang, Yi; Podlasek, Carol A.

2010-01-01

Introduction Sonic hedgehog (SHH) is an essential regulator of smooth muscle apoptosis in the penis that has significant clinical potential as a therapy to suppress post-prostatectomy apoptosis, an underlying cause of erectile dysfunction (ED). Thus an understanding of how SHH signaling is regulated in the adult penis is essential to move the field of ED research forward and to develop new treatment strategies. We propose that hedgehog-interacting protein (HIP), which has been shown to bind SHH protein and to play a role in SHH regulation during embryogenesis of other organs, is a critical regulator of SHH signaling, penile morphology, and apoptosis induction. Aims We have examined HIP signaling in the penis and cavernous nerve (CN) during postnatal differentiation of the penis, in CN-injured, and a diabetic model of ED. Methods HIP localization/abundance and RNA abundance were examined by immunohistochemical (IHC) analysis and real-time reverse transcriptase-polymerase chain reaction (RT-PCR) in Sprague-Dawley rats between the ages of 7 and 92 days old, in CN-injured Sprague-Dawley rats and in BioBreeding/Worcester diabetic rats. HIP signaling was perturbed in the pelvic ganglia and in the penis and TUNEL assay was performed in the penis. CN tie, lidocaine, and anti-kinesin experiments were performed to examine HIP signaling in the CN and penis. Results In this study we are the first to demonstrate that HIP undergoes anterograde transport to the penis via the CN, that HIP perturbation in the pelvic ganglia or the penis induces apoptosis, and that HIP plays a role in maintaining CN integrity, penile morphology, and SHH abundance. Conclusions These studies are significant because they show HIP involvement in cross-talk (signaling) between the pelvic ganglia and penis, which is integral for maintenance of penile morphology and they suggest a mechanism of how nerves may regulate target organ morphology and function. PMID:19515211

Impact of the Smoothened inhibitor, IPI-926, on smoothened ciliary localization and Hedgehog pathway activity.

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Marisa O Peluso

Full Text Available A requisite step for canonical Hedgehog (Hh pathway activation by Sonic Hedgehog (Shh ligand is accumulation of Smoothened (Smo to the primary cilium (PC. Activation of the Hh pathway has been implicated in a broad range of cancers, and several Smo antagonists are being assessed clinically, one of which is approved for the treatment of advanced basal cell carcinoma. Recent reports demonstrate that various Smo antagonists differentially impact Smo localization to the PC while still exerting inhibitory activity. In contrast to other synthetic small molecule Smo antagonists, the natural product cyclopamine binds to and promotes ciliary accumulation of Smo and "primes" cells for Hh pathway hyper-responsiveness after compound withdrawal. We compared the properties of IPI-926, a semi-synthetic cyclopamine analog, to cyclopamine with regard to potency, ciliary Smo accumulation, and Hh pathway activity after compound withdrawal. Like cyclopamine, IPI-926 promoted accumulation of Smo to the PC. However, in contrast to cyclopamine, IPI-926 treatment did not prime cells for hyper-responsiveness to Shh stimulation after compound withdrawal, but instead demonstrated continuous inhibition of signaling. By comparing the levels of drug-induced ciliary Smo accumulation with the degree of Hh pathway activity after compound withdrawal, we propose that a critical threshold of ciliary Smo is necessary for "priming" activity to occur. This "priming" appears achievable with cyclopamine, but not IPI-926, and is cell-line dependent. Additionally, IPI-926 activity was evaluated in a murine tumor xenograft model and a pharmacokinetic/pharmacodynamic relationship was examined to assess for in vivo evidence of Hh pathway hyper-responsiveness. Plasma concentrations of IPI-926 correlated with the degree and duration of Hh pathway suppression, and pathway activity did not exceed baseline levels out to 96 hours post dose. The overall findings suggest that IPI-926 possesses

Processing and turnover of the Hedgehog protein in the endoplasmic reticulum

OpenAIRE

Chen, Xin; Tukachinsky, Hanna; Huang, Chih-Hsiang; Jao, Cindy; Chu, Yue-Ru; Tang, Hsiang-Yun; Mueller, Britta; Schulman, Sol; Rapoport, Tom A.; Salic, Adrian

2011-01-01

The Hedgehog (Hh) signaling pathway has important functions during metazoan development. The Hh ligand is generated from a precursor by self-cleavage, which requires a free cysteine in the C-terminal part of the protein and results in the production of the cholesterol-modified ligand and a C-terminal fragment. In this paper, we demonstrate that these reactions occur in the endoplasmic reticulum (ER). The catalytic cysteine needs to form a disulfide bridge with a conserved cysteine, which is s...

Loss of Indian Hedgehog activates multiple aspects of a wound healing response in the mouse intestine

NARCIS (Netherlands)

van Dop, Willemijn A.; Heijmans, Jarom; Büller, Nikè V. J. A.; Snoek, Susanne A.; Rosekrans, Sanne L.; Wassenberg, Elisabeth A.; van den Bergh Weerman, Marius A.; Lanske, Beate; Clarke, Alan R.; Winton, Douglas J.; Wijgerde, Mark; Offerhaus, G. Johan; Hommes, Daan W.; Hardwick, James C.; de Jonge, Wouter J.; Biemond, Izak; van den Brink, Gijs R.

2010-01-01

Indian Hedgehog (Ihh) is expressed by the differentiated epithelial cells of the small intestine and signals to the mesenchyme where it induces unidentified factors that negatively regulate intestinal epithelial precursor cell fate. Recently, genetic variants in the Hh pathway have been linked to

Advanced basal cell carcinoma, the hedgehog pathway, and treatment options – role of smoothened inhibitors

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Fecher LA

2015-11-01

Full Text Available Leslie A Fecher,1,3 William H Sharfman2 1Department of Internal Medicine and Dermatology, Indiana University Health Simon Cancer Center, Indianapolis, IN, USA; 2The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore, MD, USA, 3Department of Internal Medicine and Dermatology, University of Michigan, MI, USA Abstract: Cutaneous basal cell carcinoma (BCC is the most common human cancer and its incidence is rising worldwide. Ultraviolet radiation exposure, including tanning bed use, as well as host factors play a role in its development. The majority of cases are treated and cured with local therapies including surgery. Yet, the health care costs of diagnosis and treatment of BCCs in the US is substantial. In the United States, the cost of nonmelanoma skin cancer care in the Medicare population is estimated to be US$426 million per year. While rare, locally advanced BCCs that can no longer be controlled with surgery and/or radiation, and metastatic BCCs do occur and can be associated with significant morbidity and mortality. Vismodegib (GDC-0449, a smoothened inhibitor targeted at the hedgehog pathway, is the first US Food and Drug Association (FDA-approved agent in the treatment of locally advanced, unresectable, and metastatic BCCs. This class of agents appears to be changing the survival rates in advanced BCC patients, but appropriate patient selection and monitoring are important. Multidisciplinary assessments are essential for the optimal care and management of these patients. For some patients with locally advanced BCC, treatment with a hedgehog inhibitor may eliminate the need for an excessively disfiguring or morbid surgery. Keywords: basal cell carcinoma, hedgehog, smoothened, vismodegib, Gorlin, basal cell nevus syndrome

Correlation of hedgehog signal activation with chemoradiotherapy sensitivity and survival in esophageal squamous cell carcinomas

International Nuclear Information System (INIS)

Zhu Weiguo; You Zhenbin; Li Tao; Yu Changhua; Tao Guangzhou; Hu Mingli; Chen Xiaofei

2011-01-01

The objective of this study was to investigate the significance of hedgehog signaling pathway in chemoradiotherapy sensitivity and its effect on the prognosis of esophageal squamous cell carcinoma. In the present study, we used the method of immunohistochemistry to examine the expression status of two hedgehog components, PTCH1 and glioma-associated oncogene GLI-1, in 100 pre-treated biopsy specimens of esophageal squamous cell carcinoma patients treated with definitive chemoradiotherapy. We find that high levels of PTCH1 and GLI-1 were detected in 76.0 and 72.0% of esophageal squamous cell carcinoma, respectively. Significant associations of high PTCH1 and GLI-1 expression with large tumor size (both P=0.01), locoregional progression (P=0.001 and 0.003, respectively) and the lack of complete response to chemoradiotherapy (P=0.008 and 0.01, respectively) were observed. Univariate analysis revealed that high PTCH1 and GLI-1 expression was associated with poor locoregional progression-free survival, distant progression-free survival and overall survival. Furthermore, esophageal squamous cell carcinoma patients with high PTCH1 and GLI-1 expression have the shorter survival time than the subgroups with negative and low PTCH1 and GLI-1 expression. In multivariate analysis, PTCH1 and GLI-1 expression status were both evaluated as independent prognostic factors for locoregional progression-free survival, distant progression-free survival and overall survival. These findings suggest an important role for the activation of hedgehog signaling in esophageal squamous cell carcinoma progression and that PTCH1 and GLI-1 expression may be significantly associated with esophageal squamous cell carcinoma resistance to chemoradiotherapy. (author)

GDC-0449-a potent inhibitor of the hedgehog pathway.

Science.gov (United States)

Robarge, Kirk D; Brunton, Shirley A; Castanedo, Georgette M; Cui, Yong; Dina, Michael S; Goldsmith, Richard; Gould, Stephen E; Guichert, Oivin; Gunzner, Janet L; Halladay, Jason; Jia, Wei; Khojasteh, Cyrus; Koehler, Michael F T; Kotkow, Karen; La, Hank; Lalonde, Rebecca L; Lau, Kevin; Lee, Leslie; Marshall, Derek; Marsters, James C; Murray, Lesley J; Qian, Changgeng; Rubin, Lee L; Salphati, Laurent; Stanley, Mark S; Stibbard, John H A; Sutherlin, Daniel P; Ubhayaker, Savita; Wang, Shumei; Wong, Susan; Xie, Minli

2009-10-01

SAR for a wide variety of heterocyclic replacements for a benzimidazole led to the discovery of functionalized 2-pyridyl amides as novel inhibitors of the hedgehog pathway. The 2-pyridyl amides were optimized for potency, PK, and drug-like properties by modifications to the amide portion of the molecule resulting in 31 (GDC-0449). Amide 31 produced complete tumor regression at doses as low as 12.5mg/kg BID in a medulloblastoma allograft mouse model that is wholly dependent on the Hh pathway for growth and is currently in human clinical trials, where it is initially being evaluated for the treatment of BCC.

Hedgehogs and sugar gliders: respiratory anatomy, physiology, and disease.

Science.gov (United States)

Johnson, Dan H

2011-05-01

This article discusses the respiratory anatomy, physiology, and disease of African pygmy hedgehogs (Atelerix albiventris) and sugar gliders (Petaurus breviceps), two species commonly seen in exotic animal practice. Where appropriate, information from closely related species is mentioned because cross-susceptibility is likely and because these additional species may also be encountered in practice. Other body systems and processes are discussed insofar as they relate to or affect respiratory function. Although some topics, such as special senses, hibernation, or vocalization, may seem out of place, in each case the information relates back to respiration in some important way. Copyright © 2011 Elsevier Inc. All rights reserved.

Exploiting members of the BAHD acyltransferase family to synthesize multiple hydroxycinnamate and benzoate conjugates in yeast

Energy Technology Data Exchange (ETDEWEB)

Eudes, Aymerick [Joint BioEnergy Institute, Emeryville, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Mouille, Maxence [Joint BioEnergy Institute, Emeryville, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Robinson, David S. [Joint BioEnergy Institute, Emeryville, CA (United States); Benites, Veronica T. [Joint BioEnergy Institute, Emeryville, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); San Francisco State Univ., San Francisco, CA (United States); Wang, George [Joint BioEnergy Institute, Emeryville, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Roux, Lucien [Joint BioEnergy Institute, Emeryville, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Ecole Polytechnique Federale de Lausanne, Lausanne (Switzerland); Tsai, Yi-Lin [Joint BioEnergy Institute, Emeryville, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Baidoo, Edward E. K. [Joint BioEnergy Institute, Emeryville, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Chiu, Tsan-Yu [Joint BioEnergy Institute, Emeryville, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Heazlewood, Joshua L. [Joint BioEnergy Institute, Emeryville, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); The Univ. of Melbourne, Melbourne, VIC (Australia); Scheller, Henrik V. [Joint BioEnergy Institute, Emeryville, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Mukhopadhyay, Aindrila [Joint BioEnergy Institute, Emeryville, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Keasling, Jay D. [Joint BioEnergy Institute, Emeryville, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Univ. of California, Berkeley, CA (United States); Technical Univ. of Denmark, Horsholm (Denmark); Deutsch, Samuel [Joint BioEnergy Institute, Emeryville, CA (United States); Loqué, Dominique [Joint BioEnergy Institute, Emeryville, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Univ. Claude Bernard Lyon 1, Villeurbanne (France)

2016-11-21

BAHD acyltransferases, named after the first four biochemically characterized enzymes of the group, are plant-specific enzymes that catalyze the transfer of coenzyme A-activated donors onto various acceptor molecules. They are responsible for the synthesis in plants of a myriad of secondary metabolites, some of which are beneficial for humans either as therapeutics or as specialty chemicals such as flavors and fragrances. The production of pharmaceutical, nutraceutical and commodity chemicals using engineered microbes is an alternative, green route to energy-intensive chemical syntheses that consume petroleum-based precursors. However, identification of appropriate enzymes and validation of their functional expression in heterologous hosts is a prerequisite for the design and implementation of metabolic pathways in microbes for the synthesis of such target chemicals. As a result, for the synthesis of valuable metabolites in the yeast Saccharomyces cerevisiae, we selected BAHD acyltransferases based on their preferred donor and acceptor substrates. In particular, BAHDs that use hydroxycinnamoyl-CoAs and/or benzoyl-CoA as donors were targeted because a large number of molecules beneficial to humans belong to this family of hydroxycinnamate and benzoate conjugates. The selected BAHD coding sequences were synthesized and cloned individually on a vector containing the Arabidopsis gene At4CL5, which encodes a promiscuous 4-coumarate:CoA ligase active on hydroxycinnamates and benzoates. The various S. cerevisiae strains obtained for co-expression of At4CL5 with the different BAHDs effectively produced a wide array of valuable hydroxycinnamate and benzoate conjugates upon addition of adequate combinations of donors and acceptor molecules. In particular, we report here for the first time the production in yeast of rosmarinic acid and its derivatives, quinate hydroxycinnamate esters such as chlorogenic acid, and glycerol hydroxycinnamate esters

A Novel Complementation Assay for Quick and Specific Screen of Genes Encoding Glycerol-3-Phosphate Acyltransferases

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Jie Lei

2018-03-01

Full Text Available The initial step in glycerolipid biosynthesis, especially in diverse allopolyploid crop species, is poorly understood, mainly due to the lack of an effective and convenient method for functional characterization of genes encoding glycerol-3-phosphate acyltransferases (GPATs catalyzing this reaction. Here we present a novel complementation assay for quick and specific characterization of GPAT-encoding genes. Its key design involves rational construction of yeast conditional lethal gat1Δgat2Δ double mutant bearing the heterologous Arabidopsis AtGPAT1 gene whose leaky expression under repressed conditions does not support any non-specific growth, thereby circumventing the false positive problem encountered with the system based on the gat1Δgat2Δ mutant harboring the native episomal GAT1 gene whose leaky expression appears to be sufficient for generating enough GPAT activities for the non-specific restoration of the mutant growth. A complementation assay developed based on this novel mutant enables quick phenotypic screen of GPAT sequences. A high degree of specificity of our assay was exemplified by its ability to differentiate effectively GPAT-encoding genes from those of other fatty acyltransferases and lipid-related sequences. Using this assay, we show that Arabidopsis AtGPAT1, AtGPAT5, and AtGPAT7 can complement the phosphatidate biosynthetic defect in the double mutants. Collectively, our assay provides a powerful tool for rapid screening, validation and optimization of GPAT sequences, aiding future engineering of the initial step of the triacylglycerol biosynthesis in oilseeds.

AMP-Activated Protein Kinase Directly Phosphorylates and Destabilizes Hedgehog Pathway Transcription Factor GLI1 in Medulloblastoma

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Yen-Hsing Li

2015-07-01

Full Text Available The Hedgehog (Hh pathway regulates cell differentiation and proliferation during development by controlling the Gli transcription factors. Cell fate decisions and progression toward organ and tissue maturity must be coordinated, and how an energy sensor regulates the Hh pathway is not clear. AMP-activated protein kinase (AMPK is an important sensor of energy stores and controls protein synthesis and other energy-intensive processes. AMPK is directly responsive to intracellular AMP levels, inhibiting a wide range of cell activities if ATP is low and AMP is high. Thus, AMPK can affect development by influencing protein synthesis and other processes needed for growth and differentiation. Activation of AMPK reduces GLI1 protein levels and stability, thus blocking Sonic-hedgehog-induced transcriptional activity. AMPK phosphorylates GLI1 at serines 102 and 408 and threonine 1074. Mutation of these three sites into alanine prevents phosphorylation by AMPK. This leads to increased GLI1 protein stability, transcriptional activity, and oncogenic potency.

Evidence that Plasmodium falciparum diacylglycerol acyltransferase is essential for intraerythrocytic proliferation

International Nuclear Information System (INIS)

Palacpac, Nirianne Marie Q.; Hiramine, Yasushi; Seto, Shintaro; Hiramatsu, Ryuji; Horii, Toshihiro; Mitamura, Toshihide

2004-01-01

In triacylglycerol (TAG)-accumulating organisms, the physiological roles of diacylglycerol acyltransferase (DGAT), a principal enzyme in the major biosynthetic pathway for TAG, appear to be diverse. Apicomplexan parasite, Plasmodium falciparum, shows unique features in TAG metabolism and trafficking during intraerythrocytic development, and unlike most eukaryotes, only one open reading frame (ORF) encoding a candidate DGAT could be found in its genome. However, whether this candidate ORF encodes P. falciparum DGAT and its physiological relevance have not been assessed. Here, we demonstrate that the ORF is transcribed as a ∼3.6 kb single mRNA throughout intraerythrocytic development, markedly elevated at trophozoite, schizont, and segmented schizont, and indeed encodes a protein exhibiting DGAT activity. Further, we provide evidence that the parasite in which the ORF was disrupted via double crossover recombination cannot be enriched, implying a fundamental role of PfDGAT in intraerythrocytic proliferation

[Traumatic spondylolysis in the hedgehog. A contribution to the problem of isthmus dysplasia].

Science.gov (United States)

Roth, M

1994-01-01

Traumatic spondylolysis in a hedgehog is reported. On the basis of that rare observation the "dysplastic" thinning of the vertebral isthmus frequently associated with spondylolysis in man is claimed to be related to the "neuroenveloping" function of the spine shared with that of the neurocranium. Dysplasia of the isthmus results from abnormal ganglio-foraminal interrelation in the embryo rather than from any primary derangement of the vertebral bone growth proper.

YAP regulates neuronal differentiation through Sonic hedgehog signaling pathway

International Nuclear Information System (INIS)

Lin, Yi-Ting; Ding, Jing-Ya; Li, Ming-Yang; Yeh, Tien-Shun; Wang, Tsu-Wei; Yu, Jenn-Yah

2012-01-01

Tight regulation of cell numbers by controlling cell proliferation and apoptosis is important during development. Recently, the Hippo pathway has been shown to regulate tissue growth and organ size in Drosophila. In mammalian cells, it also affects cell proliferation and differentiation in various tissues, including the nervous system. Interplay of several signaling cascades, such as Notch, Wnt, and Sonic Hedgehog (Shh) pathways, control cell proliferation during neuronal differentiation. However, it remains unclear whether the Hippo pathway coordinates with other signaling cascades in regulating neuronal differentiation. Here, we used P19 cells, a mouse embryonic carcinoma cell line, as a model to study roles of YAP, a core component of the Hippo pathway, in neuronal differentiation. P19 cells can be induced to differentiate into neurons by expressing a neural bHLH transcription factor gene Ascl1. Our results showed that YAP promoted cell proliferation and inhibited neuronal differentiation. Expression of Yap activated Shh but not Wnt or Notch signaling activity during neuronal differentiation. Furthermore, expression of Yap increased the expression of Patched homolog 1 (Ptch1), a downstream target of the Shh signaling. Knockdown of Gli2, a transcription factor of the Shh pathway, promoted neuronal differentiation even when Yap was over-expressed. We further demonstrated that over-expression of Yap inhibited neuronal differentiation in primary mouse cortical progenitors and Gli2 knockdown rescued the differentiation defect in Yap over-expressing cells. In conclusion, our study reveals that Shh signaling acts downstream of YAP in regulating neuronal differentiation. -- Highlights: ► YAP promotes cell proliferation and inhibits neuronal differentiation in P19 cells. ► YAP promotes Sonic hedgehog signaling activity during neuronal differentiation. ► Knockdown of Gli2 rescues the Yap-overexpression phenotype in P19 cells. ► Knockdown of Gli2 rescues the Yap

YAP regulates neuronal differentiation through Sonic hedgehog signaling pathway

Energy Technology Data Exchange (ETDEWEB)

Lin, Yi-Ting; Ding, Jing-Ya [Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taipei 112, Taiwan (China); Li, Ming-Yang [Department of Life Science, National Taiwan Normal University, Taipei 116, Taiwan (China); Yeh, Tien-Shun [Department of Anatomy and Cell Biology, National Yang-Ming University, Taipei 112, Taiwan (China); Wang, Tsu-Wei [Department of Life Science, National Taiwan Normal University, Taipei 116, Taiwan (China); Yu, Jenn-Yah [Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taipei 112, Taiwan (China); Brain Research Center, National Yang-Ming University, Taipei 112, Taiwan (China)

2012-09-10

Tight regulation of cell numbers by controlling cell proliferation and apoptosis is important during development. Recently, the Hippo pathway has been shown to regulate tissue growth and organ size in Drosophila. In mammalian cells, it also affects cell proliferation and differentiation in various tissues, including the nervous system. Interplay of several signaling cascades, such as Notch, Wnt, and Sonic Hedgehog (Shh) pathways, control cell proliferation during neuronal differentiation. However, it remains unclear whether the Hippo pathway coordinates with other signaling cascades in regulating neuronal differentiation. Here, we used P19 cells, a mouse embryonic carcinoma cell line, as a model to study roles of YAP, a core component of the Hippo pathway, in neuronal differentiation. P19 cells can be induced to differentiate into neurons by expressing a neural bHLH transcription factor gene Ascl1. Our results showed that YAP promoted cell proliferation and inhibited neuronal differentiation. Expression of Yap activated Shh but not Wnt or Notch signaling activity during neuronal differentiation. Furthermore, expression of Yap increased the expression of Patched homolog 1 (Ptch1), a downstream target of the Shh signaling. Knockdown of Gli2, a transcription factor of the Shh pathway, promoted neuronal differentiation even when Yap was over-expressed. We further demonstrated that over-expression of Yap inhibited neuronal differentiation in primary mouse cortical progenitors and Gli2 knockdown rescued the differentiation defect in Yap over-expressing cells. In conclusion, our study reveals that Shh signaling acts downstream of YAP in regulating neuronal differentiation. -- Highlights: Black-Right-Pointing-Pointer YAP promotes cell proliferation and inhibits neuronal differentiation in P19 cells. Black-Right-Pointing-Pointer YAP promotes Sonic hedgehog signaling activity during neuronal differentiation. Black-Right-Pointing-Pointer Knockdown of Gli2 rescues the Yap

Lipoproteins of slow-growing Mycobacteria carry three fatty acids and are N-acylated by Apolipoprotein N-Acyltransferase BCG_2070c.

OpenAIRE

Brülle Juliane K; Tschumi Andreas; Sander Peter

2013-01-01

BACKGROUND: Lipoproteins are virulence factors of Mycobacterium tuberculosis. Bacterial lipoproteins are modified by the consecutive action of preprolipoprotein diacylglyceryl transferase (Lgt), prolipoprotein signal peptidase (LspA) and apolipoprotein N- acyltransferase (Lnt) leading to the formation of mature triacylated lipoproteins. Lnt homologues are found in Gram-negative and high GC-rich Gram-positive, but not in low GC-rich Gram-positive bacteria, although N-acylation is observed. In ...

Congenital erythropoietic porphyria in an African hedgehog (Atelerix albiventris).

Science.gov (United States)

Wolff, Carlos; Corradini, Paulina; Cortés, Galaxia

2005-06-01

A 6-mo-old, male African hedgehog (Atelerix albiventris) presented with a history of pink urine and demonstrating pink-colored teeth and mild hepatomegaly on examination. Urinalysis revealed no physical, chemical, or cellular abnormalities other than a pink color and fluorescence under ultraviolet light (UV). Also under UV, intense fluorescence of teeth, feet, and spines was noted. Porphyria was suspected. Spectrophotometric evaluation of urine showed extremely elevated levels of copro- and uroporphyrins. Analysis of the urine by thin-layer chromatography showed an abnormal pattern of excreted porphyrin intermediates. Urine high-performance thin-layer chromatography showed that excreted porphyrins were 90-95% of the type-I isomeric form, suggestive of congenital erythropoietic porphyria.

Defect-Induced Hedgehog Polarization States in Multiferroics

Science.gov (United States)

Li, Linze; Cheng, Xiaoxing; Jokisaari, Jacob R.; Gao, Peng; Britson, Jason; Adamo, Carolina; Heikes, Colin; Schlom, Darrell G.; Chen, Long-Qing; Pan, Xiaoqing

2018-03-01

Continuous developments in nanotechnology require new approaches to materials synthesis that can produce novel functional structures. Here, we show that nanoscale defects, such as nonstoichiometric nanoregions (NSNRs), can act as nano-building blocks for creating complex electrical polarization structures in the prototypical multiferroic BiFeO3 . An array of charged NSNRs are produced in BiFeO3 thin films by tuning the substrate temperature during film growth. Atomic-scale scanning transmission electron microscopy imaging reveals exotic polarization rotation patterns around these NSNRs. These polarization patterns resemble hedgehog or vortex topologies and can cause local changes in lattice symmetries leading to mixed-phase structures resembling the morphotropic phase boundary with high piezoelectricity. Phase-field simulations indicate that the observed polarization configurations are mainly induced by charged states at the NSNRs. Engineering defects thus may provide a new route for developing ferroelectric- or multiferroic-based nanodevices.

Novel lysophospholipid acyltransferase PLAT1 of Aurantiochytrium limacinum F26-b responsible for generation of palmitate-docosahexaenoate-phosphatidylcholine and phosphatidylethanolamine.

Directory of Open Access Journals (Sweden)

Eriko Abe

Full Text Available N-3 polyunsaturated fatty acids (PUFA, such as docosahexaenoic acid (DHA, 22:6n-3, have been reported to play roles in preventing cardiovascular diseases. The major source of DHA is fish oils but a recent increase in the global demand of DHA and decrease in fish stocks require a substitute. Thraustochytrids, unicellular marine protists belonging to the Chromista kingdom, can synthesize large amounts of DHA, and, thus, are expected to be an alternative to fish oils. DHA is found in the acyl chain(s of phospholipids as well as triacylglycerols in thraustochytrids; however, how thraustochytrids incorporate DHA into phospholipids remains unknown. We report here a novel lysophospholipid acyltransferase (PLAT1, which is responsible for the generation of DHA-containing phosphatidylcholine and phosphatidylethanolamine in thraustochytrids. The PLAT1 gene, which was isolated from the genomic DNA of Aurantiochytrium limacinum F26-b, was expressed in Saccharomyces cerevisiae, and the FLAG-tagged recombinant enzyme was characterized after purification with anti-FLAG affinity gel. PLAT1 shows wide specificity for donor substrates as well as acceptor substrates in vitro, i.e, the enzyme can adopt lysophosphatidylcholine, lysophosphatidylethanolamine, lysophosphatidylserine and lysophosphatidylinositol as acceptor substrates, and 15:0/16:0-CoA and DHA-CoA as donor substrates. In contrast to the in vitro experiment, only lysophosphatidylcholine acyltransferase and lysophosphatidylethanolamine acyltransferase activities were decreased in plat1-knockout mutants, resulting in a decrease of 16:0-DHA-phosphatidylcholine (PC [PC(38:6] and 16:0-DHA-phosphatidylethanolamine (PE [PE(38:6], which are two major DHA-containing phospholipids in A. limacinum F26-b. However, the amounts of other phospholipid species including DHA-DHA-PC [PC(44:12] and DHA-DHA-PE [PE(44:12] were almost the same in plat-knockout mutants and the wild-type. These results indicate that PLAT1 is the

Catalytic center of lecithin:cholesterol acyltransferase: isolation and sequence of diisopropyl fluorophosphate-labeled peptides

Energy Technology Data Exchange (ETDEWEB)

Park, Y.B.; Yueksel, U.G.; Gracy, R.W.; Lacko, A.G.

1987-02-27

Lecithin:cholesterol acyltransferase (LCAT) was purified from hog plasma and subsequently reacted with (/sup 3/H)-Diisopropyl fluorophosphate (DFP). The labeled enzyme was digested with pepsin and the peptides separated by high performance liquid chromatography (HPLC). Two radioactive peptides were isolated, subjected to automated amino acid sequencing and yielded the following data: A) Ile-Ser-Leu-Gly-Ala-Pro-Trp-Gly-Gly-Ser, and B) Tyr-Ile-Phe-Asp-x-Gly-Phe-Pro-Tyr-x-Asp-Pro-Val. Both of these sequences represent very highly conserved regions of the enzyme when compared to the sequence of human LCAT. Peptide (A) is considered to represent the catalytic center of LCAT based on comparisons with data reported in the literature.

The role of acyl-CoA:diacylglycerol acyltransferase (DGAT) in energy metabolism.

Science.gov (United States)

Yu, Yi-Hao; Ginsberg, Henry N

2004-01-01

Acyl-CoA:diacylglycerol acyltransferase (DGAT, EC2.3.1.20), a key enzyme in triglyceride (TG) biosynthesis, not only participates in lipid metabolism but also influences metabolic pathways of other fuel molecules. Changes in the expression and/or activity levels of DGAT may lead to changes in systemic insulin sensitivity and energy homeostasis. The synthetic role of DGAT in adipose tissue, the liver, and the intestine, sites where endogenous levels of DGAT activity and TG synthesis are high, is relatively clear. Less clear is whether DGAT plays a mediating or preventive role in the development of ectopic lipotoxicity in tissues such as muscle and the pancreas, when their supply of free fatty acids (FFAs) exceeds their needs. Future studies with tissue-specific overexpression and/or knockout in these animal models would be expected to shed additional light on these issues.

Pharmacodynamic and pharmacokinetic neoadjuvant study of hedgehog pathway inhibitor Sonidegib (LDE-225) in men with high-risk localized prostate cancer undergoing prostatectomy.

Science.gov (United States)

Ross, Ashley E; Hughes, Robert M; Glavaris, Stephanie; Ghabili, Kamyar; He, Ping; Anders, Nicole M; Harb, Rana; Tosoian, Jeffrey J; Marchionni, Luigi; Schaeffer, Edward M; Partin, Alan W; Allaf, Mohamad E; Bivalacqua, Trinity J; Chapman, Carolyn; O'Neal, Tanya; DeMarzo, Angelo M; Hurley, Paula J; Rudek, Michelle A; Antonarakis, Emmanuel S

2017-11-28

To determine the pharmacodynamic effects of Sonidegib (LDE-225) in prostate tumor tissue from men with high-risk localized prostate cancer, by comparing pre-surgical core-biopsy specimens to tumor tissue harvested post-treatment at prostatectomy. We conducted a prospective randomized (Sonidegib vs. observation) open-label translational clinical trial in men with high-risk localized prostate cancer undergoing radical prostatectomy. The primary endpoint was the proportion of patients in each arm who achieved at least a two-fold reduction in GLI1 mRNA expression in post-treatment versus pre-treatment tumor tissue. Secondary endpoints included the effect of pre-surgical treatment with Sonidegib on disease progression following radical prostatectomy, and safety. Fourteen men were equally randomized (7 per arm) to either neoadjuvant Sonidegib or observation for 4 weeks prior to prostatectomy. Six of seven men (86%) in the Sonidegib arm (and none in the control group) achieved a GLI1 suppression of at least two-fold. In the Sonidegib arm, drug was detectable in plasma and in prostatic tissue; and median intra-patient GLI1 expression decreased by 63-fold, indicating potent suppression of Hedgehog signaling. Sonidegib was well tolerated, without any Grade 3-4 adverse events observed. Disease-free survival was comparable among the two arms (HR = 1.50, 95% CI 0.26-8.69, P = 0.65). Hedgehog pathway activity (as measured by GLI1 expression) was detectable at baseline in men with localized high-risk prostate cancer. Sonidegib penetrated into prostatic tissue and induced a >60-fold suppression of the Hedgehog pathway. The oncological benefit of Hedgehog pathway inhibition in prostate cancer remains unclear.

Therapeutic strategies for metabolic diseases: Small-molecule diacylglycerol acyltransferase (DGAT) inhibitors.

Science.gov (United States)

Naik, Ravi; Obiang-Obounou, Brice W; Kim, Minkyoung; Choi, Yongseok; Lee, Hyun Sun; Lee, Kyeong

2014-11-01

Metabolic diseases such as atherogenic dyslipidemia, hepatic steatosis, obesity, and type II diabetes are emerging as major global health problems. Acyl-CoA:diacylglycerol acyltransferase (DGAT) is responsible for catalyzing the final reaction in the glycerol phosphate pathway of triglycerol synthesis. It has two isoforms, DGAT-1 and DGAT-2, which are widely expressed and present in white adipose tissue. DGAT-1 is most highly expressed in the small intestine, whereas DGAT-2 is primarily expressed in the liver. Therefore, the selective inhibition of DGAT-1 has become an attractive target with growing potential for the treatment of obesity and type II diabetes. Furthermore, DGAT-2 has been suggested as a new target for the treatment of DGAT-2-related liver diseases including hepatic steatosis, hepatic injury, and fibrosis. In view the discovery of drugs that target DGAT, herein we attempt to provide insight into the scope and further reasons for optimization of DGAT inhibitors. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Diacylglycerol acyltransferase-1 (DGAT1 inhibition perturbs postprandial gut hormone release.

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Hua V Lin

Full Text Available Diacylglycerol acyltransferase-1 (DGAT1 is a potential therapeutic target for treatment of obesity and related metabolic diseases. However, the degree of DGAT1 inhibition required for metabolic benefits is unclear. Here we show that partial DGAT1 deficiency in mice suppressed postprandial triglyceridemia, led to elevations in glucagon-like peptide-1 (GLP-1 and peptide YY (PYY only following meals with very high lipid content, and did not protect from diet-induced obesity. Maximal DGAT1 inhibition led to enhanced GLP-1 and PYY secretion following meals with physiologically relevant lipid content. Finally, combination of DGAT1 inhibition with dipeptidyl-peptidase-4 (DPP-4 inhibition led to further enhancements in active GLP-1 in mice and dogs. The current study suggests that targeting DGAT1 to enhance postprandial gut hormone secretion requires maximal inhibition, and suggests combination with DPP-4i as a potential strategy to develop DGAT1 inhibitors for treatment of metabolic diseases.

New insights into the catalytic mechanism of human glycine N-acyltransferase.

Science.gov (United States)

van der Sluis, Rencia; Ungerer, Vida; Nortje, Carla; A van Dijk, Alberdina; Erasmus, Elardus

2017-11-01

Even though the glycine conjugation pathway was one of the first metabolic pathways to be discovered, this pathway remains very poorly characterized. The bi-substrate kinetic parameters of a recombinant human glycine N-acyltransferase (GLYAT, E.C. 2.3.1.13) were determined using the traditional colorimetric method and a newly developed HPLC-ESI-MS/MS method. Previous studies analyzing the kinetic parameters of GLYAT, indicated a random Bi-Bi and/or ping-pong mechanism. In this study, the hippuric acid concentrations produced by the GLYAT enzyme reaction were analyzed using the allosteric sigmoidal enzyme kinetic module. Analyses of the initial rate (v) against substrate concentration plots, produced a sigmoidal curve (substrate activation) when the benzoyl-CoA concentrations was kept constant, whereas the plot with glycine concentrations kept constant, passed through a maximum (substrate inhibition). Thus, human GLYAT exhibits mechanistic kinetic cooperativity as described by the Ferdinand enzyme mechanism rather than the previously assumed Michaelis-Menten reaction mechanism. © 2017 Wiley Periodicals, Inc.

Mice Deficient in lysophosphatidic acid acyltransferase delta (Lpaatδ)/acylglycerophosphate acyltransferase 4 (Agpat4) Have Impaired Learning and Memory.

Science.gov (United States)

Bradley, Ryan M; Mardian, Emily B; Bloemberg, Darin; Aristizabal Henao, Juan J; Mitchell, Andrew S; Marvyn, Phillip M; Moes, Katherine A; Stark, Ken D; Quadrilatero, Joe; Duncan, Robin E

2017-11-15

We previously characterized LPAATδ/AGPAT4 as a mitochondrial lysophosphatidic acid acyltransferase that regulates brain levels of phosphatidylcholine (PC), phosphatidylethanolamine (PE), and phosphatidylinositol (PI). Here, we report that Lpaat δ -/- mice display impaired spatial learning and memory compared to wild-type littermates in the Morris water maze and our investigation of potential mechanisms associated with brain phospholipid changes. Marker protein immunoblotting suggested that the relative brain content of neurons, glia, and oligodendrocytes was unchanged. Relative abundance of the important brain fatty acid docosahexaenoic acid was also unchanged in phosphatidylserine, phosphatidylglycerol, and cardiolipin, in agreement with prior data on PC, PE and PI. In phosphatidic acid, it was increased. Specific decreases in ethanolamine-containing phospholipids were detected in mitochondrial lipids, but the function of brain mitochondria in Lpaat δ -/- mice was unchanged. Importantly, we found that Lpaat δ -/- mice have a significantly and drastically lower brain content of the N -methyl-d-asparate (NMDA) receptor subunits NR1, NR2A, and NR2B, as well as the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor subunit GluR1, compared to wild-type mice. However, general dysregulation of PI-mediated signaling is not likely responsible, since phospho-AKT and phospho-mTOR pathway regulation was unaffected. Our findings indicate that Lpaat δ deficiency causes deficits in learning and memory associated with reduced NMDA and AMPA receptors. Copyright © 2017 American Society for Microbiology.

Effects of the diacylglycerol o-acyltransferase 1 (DGAT1) K232A polymorphism on fatty acid, protein, and mineral composition of dairy cattle milk

NARCIS (Netherlands)

Bovenhuis, H.; Visker, M.H.P.W.; Poulsen, N.A.; Sehested, J.; Valenberg, van H.J.F.; Arendonk, van J.A.M.; Larsen, L.B.; Buitenhuis, A.J.

2016-01-01

Several studies have described associations between the diacylglycerol o-acyltransferase 1 (DGAT1) K232A polymorphism and routinely collected milk production traits but not much is known about effects of the DGAT1 polymorphism on detailed milk composition. The aim of this study was to estimate

Synthetic triterpenoid inhibition of human ghrelin O-acyltransferase: Involvement of a functionally required cysteine provides mechanistic insight into ghrelin acylation

OpenAIRE

McGovern-Gooch, Kayleigh R.; Mahajani, Nivedita S.; Garagozzo, Ariana; Schramm, Anthony J.; Hannah, Lauren G.; Sieburg, Michelle A.; Chisholm, John D.; Hougland, James L.

2017-01-01

The peptide hormone ghrelin plays a key role in regulating hunger and energy balance within the body. Ghrelin signaling presents a promising and unexploited target for development of small-molecule therapeutics to treat obesity, diabetes, and other health conditions. Inhibition of ghrelin O-acyltransferase (GOAT), which catalyzes an essential octanoylation step in ghrelin maturation, offers a potential avenue for controlling ghrelin signaling. Through screening a small molecule library, we ha...

Correlation Between Hedgehog (Hh) Protein Family and Brain-Derived Neurotrophic Factor (BDNF) in Autism Spectrum Disorder (ASD).

Science.gov (United States)

Halepoto, Dost Muhammad; Bashir, Shahid; Zeina, Rana; Al-Ayadhi, Laila Y

2015-12-01

To determine the correlation of Sonic Hedgehog (SHH), Indian Hedgehog (IHH), and Brain-Derived Neurotrophic Factor (BDNF) in children with Autism Spectrum Disorder (ASD). An observational, comparative study. Autism Research and Treatment Center, Al-Amodi Autism Research Chair, Department of Physiology, Faculty of Medicine, King Khalid University Hospital, King Saud University, Riyadh, Saudi Arabia, from October 2011 to May 2012. Serum levels of SHH, IHH and BDNF were determined in recently diagnosed autistic patients and age-matched healthy children (n=25), using the Enzyme-Linked Immunosorbent Assay (ELISA). Childhood Autism Rating Scale (CARS) was used for the assessment of autistic severity. Spearman correlation co-efficient 'r' was determined. The serum levels of IHH and SHH were significantly higher in autistic subjects than those of control subjects. There was significant correlation between age and IHH (r = 0.176, p = 0.03), BDNF and severe IHH (r = 0.1763, p = 0.003), and severe BDNF and severe SHH (r = 0.143, p autism.

Sonic hedgehog protein promotes proliferation and chondrogenic differentiation of bone marrow-derived mesenchymal stem cells in vitro.

Science.gov (United States)

Warzecha, Jörg; Göttig, Stephan; Brüning, Christian; Lindhorst, Elmar; Arabmothlagh, Mohammad; Kurth, Andreas

2006-10-01

Sonic hedgehog (Shh) protein is known to be an important signaling protein in early embryonic development. Also, Shh is involved in the induction of early cartilaginous differentiation of mesenchymal cells in the limb and in the spine. The impact of Shh on adult stem cells, human bone marrow-derived mesenchymal stem cells (MSCs), was tested. The MSCs were treated either with recombinant Sonic hedgehog protein (r-Shh) or with transforming growth factor-beta 1 (TGF-beta(1)) as a positive control in vitro for 3 weeks. The effects on cartilaginous differentiation and proliferation were assayed. MSCs when treated with either Shh or TGF-beta(1) showed expression of cartilage markers aggrecan, Sox9, CEP-68, and collagen type II and X within 3 weeks. Only r-Shh-treated cells showed a very strong cell proliferation and much higher BrdU incorporation in cell assay systems. These are the first data that indicate an important role of Shh for the induction of cartilage production by MSCs in vitro.

Elevated Fibroblast Growth Factor Signaling Is Critical for the Pathogenesis of the Dwarfism in Evc2/Limbin Mutant Mice.

Science.gov (United States)

Zhang, Honghao; Kamiya, Nobuhiro; Tsuji, Takehito; Takeda, Haruko; Scott, Greg; Rajderkar, Sudha; Ray, Manas K; Mochida, Yoshiyuki; Allen, Benjamin; Lefebvre, Veronique; Hung, Irene H; Ornitz, David M; Kunieda, Tetsuo; Mishina, Yuji

2016-12-01

Ellis-van Creveld (EvC) syndrome is a skeletal dysplasia, characterized by short limbs, postaxial polydactyly, and dental abnormalities. EvC syndrome is also categorized as a ciliopathy because of ciliary localization of proteins encoded by the two causative genes, EVC and EVC2 (aka LIMBIN). While recent studies demonstrated important roles for EVC/EVC2 in Hedgehog signaling, there is still little known about the pathophysiological mechanisms underlying the skeletal dysplasia features of EvC patients, and in particular why limb development is affected, but not other aspects of organogenesis that also require Hedgehog signaling. In this report, we comprehensively analyze limb skeletogenesis in Evc2 mutant mice and in cell and tissue cultures derived from these mice. Both in vivo and in vitro data demonstrate elevated Fibroblast Growth Factor (FGF) signaling in Evc2 mutant growth plates, in addition to compromised but not abrogated Hedgehog-PTHrP feedback loop. Elevation of FGF signaling, mainly due to increased Fgf18 expression upon inactivation of Evc2 in the perichondrium, critically contributes to the pathogenesis of limb dwarfism. The limb dwarfism phenotype is partially rescued by inactivation of one allele of Fgf18 in the Evc2 mutant mice. Taken together, our data uncover a novel pathogenic mechanism to understand limb dwarfism in patients with Ellis-van Creveld syndrome.

Elevated Fibroblast Growth Factor Signaling Is Critical for the Pathogenesis of the Dwarfism in Evc2/Limbin Mutant Mice.

Directory of Open Access Journals (Sweden)

Honghao Zhang

2016-12-01

Full Text Available Ellis-van Creveld (EvC syndrome is a skeletal dysplasia, characterized by short limbs, postaxial polydactyly, and dental abnormalities. EvC syndrome is also categorized as a ciliopathy because of ciliary localization of proteins encoded by the two causative genes, EVC and EVC2 (aka LIMBIN. While recent studies demonstrated important roles for EVC/EVC2 in Hedgehog signaling, there is still little known about the pathophysiological mechanisms underlying the skeletal dysplasia features of EvC patients, and in particular why limb development is affected, but not other aspects of organogenesis that also require Hedgehog signaling. In this report, we comprehensively analyze limb skeletogenesis in Evc2 mutant mice and in cell and tissue cultures derived from these mice. Both in vivo and in vitro data demonstrate elevated Fibroblast Growth Factor (FGF signaling in Evc2 mutant growth plates, in addition to compromised but not abrogated Hedgehog-PTHrP feedback loop. Elevation of FGF signaling, mainly due to increased Fgf18 expression upon inactivation of Evc2 in the perichondrium, critically contributes to the pathogenesis of limb dwarfism. The limb dwarfism phenotype is partially rescued by inactivation of one allele of Fgf18 in the Evc2 mutant mice. Taken together, our data uncover a novel pathogenic mechanism to understand limb dwarfism in patients with Ellis-van Creveld syndrome.

Elevated Fibroblast Growth Factor Signaling Is Critical for the Pathogenesis of the Dwarfism in Evc2/Limbin Mutant Mice

Science.gov (United States)

Zhang, Honghao; Kamiya, Nobuhiro; Tsuji, Takehito; Takeda, Haruko; Scott, Greg; Ray, Manas K.; Mochida, Yoshiyuki; Lefebvre, Veronique; Hung, Irene H.; Kunieda, Tetsuo; Mishina, Yuji

2016-01-01

Ellis-van Creveld (EvC) syndrome is a skeletal dysplasia, characterized by short limbs, postaxial polydactyly, and dental abnormalities. EvC syndrome is also categorized as a ciliopathy because of ciliary localization of proteins encoded by the two causative genes, EVC and EVC2 (aka LIMBIN). While recent studies demonstrated important roles for EVC/EVC2 in Hedgehog signaling, there is still little known about the pathophysiological mechanisms underlying the skeletal dysplasia features of EvC patients, and in particular why limb development is affected, but not other aspects of organogenesis that also require Hedgehog signaling. In this report, we comprehensively analyze limb skeletogenesis in Evc2 mutant mice and in cell and tissue cultures derived from these mice. Both in vivo and in vitro data demonstrate elevated Fibroblast Growth Factor (FGF) signaling in Evc2 mutant growth plates, in addition to compromised but not abrogated Hedgehog-PTHrP feedback loop. Elevation of FGF signaling, mainly due to increased Fgf18 expression upon inactivation of Evc2 in the perichondrium, critically contributes to the pathogenesis of limb dwarfism. The limb dwarfism phenotype is partially rescued by inactivation of one allele of Fgf18 in the Evc2 mutant mice. Taken together, our data uncover a novel pathogenic mechanism to understand limb dwarfism in patients with Ellis-van Creveld syndrome. PMID:28027321

Acute and chronic effects of a 24-hour intravenous triglyceride emulsion challenge on plasma lecithin : cholesterol acyltransferase, phospholipid transfer protein, and cholesteryl ester transfer protein activities

NARCIS (Netherlands)

Riemens, SC; Van Tol, A; Sluiter, WJ; Dullaart, RPF

Lecithin:cholesterol acyltransferase (LCAT), phospholipid transfer protein (PLTP), and cholesteryl ester transfer protein (CETP) are key factors in remodeling of high density lipoproteins (HDL) and triglyceride-rich lipoproteins. We examined the effect of a large, 24 h intravenous fat load on plasma

Aerobic, Metal-Free, and Catalytic Dehydrogenative Coupling of Heterocycles: En Route to Hedgehog Signaling Pathway Inhibitors.

Science.gov (United States)

Bering, Luis; Paulussen, Felix M; Antonchick, Andrey P

2018-04-06

The nitrosonium ion-catalyzed dehydrogenative coupling of heteroarenes under mild reaction conditions is reported. The developed method utilizes ambient molecular oxygen as a terminal oxidant, and only water is produced as byproduct. Dehydrogenative coupling of heteroarenes translated into the rapid discovery of novel hedgehog signaling pathway inhibitors, emphasizing the importance of the developed methodology.

Structural and Affinity Determinants in the Interaction between Alcohol Acyltransferase from F. x ananassa and Several Alcohol Substrates: A Computational Study.

Directory of Open Access Journals (Sweden)

Carlos Navarro-Retamal

Full Text Available Aroma and flavor are important factors of fruit quality and consumer preference. The specific pattern of aroma is generated during ripening by the accumulation of volatiles compounds, which are mainly esters. Alcohol acyltransferase (AAT (EC 2.3.1.84 catalyzes the esterification reaction of aliphatic and aromatic alcohols and acyl-CoA into esters in fruits and flowers. In Fragaria x ananassa, there are different volatiles compounds that are obtained from different alcohol precursors, where octanol and hexanol are the most abundant during fruit ripening. At present, there is not structural evidence about the mechanism used by the AAT to synthesize esters. Experimental data attribute the kinetic role of this enzyme to 2 amino acidic residues in a highly conserved motif (HXXXD that is located in the middle of the protein. With the aim to understand the molecular and energetic aspects of volatiles compound production from F. x ananassa, we first studied the binding modes of a series of alcohols, and also different acyl-CoA substrates, in a molecular model of alcohol acyltransferase from Fragaria x ananassa (SAAT using molecular docking. Afterwards, the dynamical behavior of both substrates, docked within the SAAT binding site, was studied using routine molecular dynamics (MD simulations. In addition, in order to correlate the experimental and theoretical data obtained in our laboratories, binding free energy calculations were performed; which previous results suggested that octanol, followed by hexanol, presented the best affinity for SAAT. Finally, and concerning the SAAT molecular reaction mechanism, it is suggested from molecular dynamics simulations that the reaction mechanism may proceed through the formation of a ternary complex, in where the Histidine residue at the HXXXD motif deprotonates the alcohol substrates. Then, a nucleophilic attack occurs from alcohol charged oxygen atom to the carbon atom at carbonyl group of the acyl CoA. This

Generalized hedgehog ansatz and Gribov copies in regions with nontrivial topologies

Science.gov (United States)

Canfora, Fabrizio; Salgado-Rebolledo, Patricio

2013-02-01

In this paper the arising of Gribov copies both in Landau and Coulomb gauges in regions with nontrivial topologies but flat metric, (such as closed tubes S1×D2, or R×T2) will be analyzed. Using a novel generalization of the hedgehog ansatz beyond spherical symmetry, analytic examples of Gribov copies of the vacuum will be constructed. Using such ansatz, we will also construct the elliptic Gribov pendulum. The requirement of absence of Gribov copies of the vacuum satisfying the strong boundary conditions implies geometrical constraints on the shapes and sizes of the regions with nontrivial topologies.

Sonic hedgehog from both nerves and epithelium is a key trophic factor for taste bud maintenance.

Science.gov (United States)

Castillo-Azofeifa, David; Losacco, Justin T; Salcedo, Ernesto; Golden, Erin J; Finger, Thomas E; Barlow, Linda A

2017-09-01

The integrity of taste buds is intimately dependent on an intact gustatory innervation, yet the molecular nature of this dependency is unknown. Here, we show that differentiation of new taste bud cells, but not progenitor proliferation, is interrupted in mice treated with a hedgehog (Hh) pathway inhibitor (HPI), and that gustatory nerves are a source of sonic hedgehog (Shh) for taste bud renewal. Additionally, epithelial taste precursor cells express Shh transiently, and provide a local supply of Hh ligand that supports taste cell renewal. Taste buds are minimally affected when Shh is lost from either tissue source. However, when both the epithelial and neural supply of Shh are removed, taste buds largely disappear. We conclude Shh supplied by taste nerves and local taste epithelium act in concert to support continued taste bud differentiation. However, although neurally derived Shh is in part responsible for the dependence of taste cell renewal on gustatory innervation, neurotrophic support of taste buds likely involves a complex set of factors. © 2017. Published by The Company of Biologists Ltd.

Cold labelled substrate and estimation of cholesterol esterification rate in lecithin cholesterol acyltransferase radioassay

International Nuclear Information System (INIS)

Dobiasova, M.; Schuetzova, M.

1986-01-01

A new method is described of cold labelling of blood serum, plasma and body fluids containing lecithin cholesterol acyltransferase (LCAT) and/or lipoproteins for radioassay to assess the cholesterol esterification rate. The method uses the principle of transfer, in refrigeration conditions, of 14 C-cholesterol from filter paper discs to the fluids. The preparation of the disc guarantees homogeneous labelling and high stability. The use of the labelling disc was shown to be reliable, easy and fast and suitable for accurate assessment of LCAT reaction, applicable in the widest possible enzyme concentration range. It was also, found suited for the measurement of the esterification rate of rabbit intraocular fluid which is a medium with the lowest contents of the substrate and LCAT. (L.O.)

Diacylglycerol Acyltransferase 1 Is Regulated by Its N-Terminal Domain in Response to Allosteric Effectors.

Science.gov (United States)

Caldo, Kristian Mark P; Acedo, Jeella Z; Panigrahi, Rashmi; Vederas, John C; Weselake, Randall J; Lemieux, M Joanne

2017-10-01

Diacylglycerol acyltransferase 1 (DGAT1) is an integral membrane enzyme catalyzing the final and committed step in the acyl-coenzyme A (CoA)-dependent biosynthesis of triacylglycerol (TAG). The biochemical regulation of TAG assembly remains one of the least understood areas of primary metabolism to date. Here, we report that the hydrophilic N-terminal domain of Brassica napus DGAT1 (BnaDGAT1 1-113 ) regulates activity based on acyl-CoA/CoA levels. The N-terminal domain is not necessary for acyltransferase activity and is composed of an intrinsically disordered region and a folded segment. We show that the disordered region has an autoinhibitory function and a dimerization interface, which appears to mediate positive cooperativity, whereas the folded segment of the cytosolic region was found to have an allosteric site for acyl-CoA/CoA. Under increasing acyl-CoA levels, the binding of acyl-CoA with this noncatalytic site facilitates homotropic allosteric activation. Enzyme activation, on the other hand, is prevented under limiting acyl-CoA conditions (low acyl-CoA-to-CoA ratio), whereby CoA acts as a noncompetitive feedback inhibitor through interaction with the same folded segment. The three-dimensional NMR solution structure of the allosteric site revealed an α-helix with a loop connecting a coil fragment. The conserved amino acid residues in the loop interacting with CoA were identified, revealing details of this important regulatory element for allosteric regulation. Based on these results, a model is proposed illustrating the role of the N-terminal domain of BnaDGAT1 as a positive and negative modulator of TAG biosynthesis. © 2017 American Society of Plant Biologists. All Rights Reserved.

Genetic variation of the ghrelin activator gene ghrelin O-acyltransferase (GOAT) is associated with anorexia nervosa.

Science.gov (United States)

Müller, Timo D; Tschöp, Matthias H; Jarick, Ivonne; Ehrlich, Stefan; Scherag, Susann; Herpertz-Dahlmann, Beate; Zipfel, Stefan; Herzog, Wolfgang; de Zwaan, Martina; Burghardt, Roland; Fleischhaker, Christian; Klampfl, Karin; Wewetzer, Christoph; Herpertz, Stephan; Zeeck, Almut; Tagay, Sefik; Burgmer, Markus; Pfluger, Paul T; Scherag, André; Hebebrand, Johannes; Hinney, Anke

2011-05-01

The gastrointestinal peptide hormone ghrelin promotes food intake and increases body weight and adiposity through activation of the growth hormone secretagogue receptor (GHSR1a). To promote its biological action ghrelin is acylated at its serine 3 residue by the recently discovered ghrelin O-acyltransferase (GOAT, a.k.a. membrane-bound O-acyltransferase 4, MBOAT4). Plasma levels of total and acyl-ghrelin are negatively correlated with body-mass-index (BMI); as lower the BMI as higher plasma levels of total and acylated ghrelin and vice versa. Accordingly, plasma levels of total and acyl-ghrelin are elevated in patients with anorexia nervosa (AN) and decline upon weight regain. The importance of the endogenous Goat/ghrelin system in the neuroendocrine adaptation to fasting was recently highlighted by the observation that acyl-ghrelin mediated elevation of growth hormone (GH) release prevents starvation induced hypoglycemia in Goat(-/-) mice. The aim of this study was to test if genetic variation of GOAT is implicated in the etiology of AN. We therefore assessed association of 6 tagging single nucleotide polymorphisms (tagSNPs), which were predicted to cover 96% the common genetic variability of GOAT plus 50 kb of the 5' and 3' flanking region, in 543 German patients with AN and 612 German normal and underweight healthy controls. Based on a recessive mode of inheritance we observed some evidence for association of the G/G genotype at SNP rs10096097 with AN (nominal two-sided p = 0.031). Based on our results we conclude that genetic variation in GOAT might be implicated in the etiology of AN. Copyright © 2010 Elsevier Ltd. All rights reserved.

HedgeHOGS: A Rapid Nuclear Hedge Sizing and Analysis Tool

Energy Technology Data Exchange (ETDEWEB)

Reynolds, Adam F. [United States Military Academy, West Point, NY (United States); Steinfeldt, Bradley Alexander [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Lafleur, Jarret Marshall [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Hawley, Marilyn F. [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Shannon, Lisa M. [Sandia National Lab. (SNL-CA), Livermore, CA (United States)

2017-07-01

The U.S. nuclear stockpile hedge is an inventory of non-deployed nuclear warheads and a force structure capable of deploying those warheads. Current guidance is to retain this hedge to mitigate the risk associated with the technical failure of any single warhead type or adverse geopolitical developments that could require augmentation of the force. The necessary size of the hedge depends on the composition of the nuclear stockpile and assumed constraints. Knowing the theoretical minimum hedge given certain constraints is useful when considering future weapons policy. HedgeHOGS, an Excel-based tool, was developed to enable rapid calculation of the minimum hedge size associated with varying active stockpile composition and hedging strategies.

Arsenic inhibits hedgehog signaling during P19 cell differentiation

Energy Technology Data Exchange (ETDEWEB)

Liu, Jui Tung [Environmental Toxicology Program, Clemson University, 132 Long Hall, Clemson, SC 29634 (United States); Bain, Lisa J., E-mail: lbain@clemson.edu [Environmental Toxicology Program, Clemson University, 132 Long Hall, Clemson, SC 29634 (United States); Department of Biological Sciences, Clemson University, 132 Long Hall, Clemson, SC 29634 (United States)

2014-12-15

Arsenic is a toxicant found in ground water around the world, and human exposure mainly comes from drinking water or from crops grown in areas containing arsenic in soils or water. Epidemiological studies have shown that arsenic exposure during development decreased intellectual function, reduced birth weight, and altered locomotor activity, while in vitro studies have shown that arsenite decreased muscle and neuronal cell differentiation. The sonic hedgehog (Shh) signaling pathway plays an important role during the differentiation of both neurons and skeletal muscle. The purpose of this study was to investigate whether arsenic can disrupt Shh signaling in P19 mouse embryonic stem cells, leading to changes muscle and neuronal cell differentiation. P19 embryonic stem cells were exposed to 0, 0.25, or 0.5 μM of sodium arsenite for up to 9 days during cell differentiation. We found that arsenite exposure significantly reduced transcript levels of genes in the Shh pathway in both a time and dose-dependent manner. This included the Shh ligand, which was decreased 2- to 3-fold, the Gli2 transcription factor, which was decreased 2- to 3-fold, and its downstream target gene Ascl1, which was decreased 5-fold. GLI2 protein levels and transcriptional activity were also reduced. However, arsenic did not alter GLI2 primary cilium accumulation or nuclear translocation. Moreover, additional extracellular SHH rescued the inhibitory effects of arsenic on cellular differentiation due to an increase in GLI binding activity. Taken together, we conclude that arsenic exposure affected Shh signaling, ultimately decreasing the expression of the Gli2 transcription factor. These results suggest a mechanism by which arsenic disrupts cell differentiation. - Highlights: • Arsenic exposure decreases sonic hedgehog pathway-related gene expression. • Arsenic decreases GLI2 protein levels and transcriptional activity in P19 cells. • Arsenic exposure does not alter the levels of SHH

Cooperation of Indian Hedgehog and Vascular Endothelial Growth Factor in Tumor Angiogenesis and Growth in Human Hepatocellular Carcinomas, an Immunohistochemical Study.

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Li, Yang; Liu, Yang; Wang, Guangxi; Wang, Yuxiang; Guo, Limei

2018-04-07

The Hedgehog pathway was recently shown to be involved in vascular development and neovascularization in human embryogenesis and disease. However, the role of Hedgehog pathway in modulating tumor angiogenesis is still unexplored. In the current study, we investigated the expression of Indian Hedgehog (Ihh) and vascular endothelial cell growth factor (VEGF) in human hepatocellular carcinomas (HCCs) with immunohistochemical staining and compared the immunoreaction data with various clinicopathologic characteristics. Immunoreactivity of Ihh and VEGF proteins was observed in 61.5% (56/91) and 64.5% (59/91) cases of HCC tumor tissues, respectively, which was considerably higher than the adjacent nonmalignant tissues. Ihh protein was observed predominantly in the cytoplasm of the tumor cells with a staining pattern of which was sparse and dot-like, or circular around the cell membrane. VEGF protein was expressed heterogenously in the cytoplasm in tumor cells and was negative in peritumoral areas in all cases. CD34 showed diffuse staining in the tumor parenchyma in most HCC specimens. The association of expression of Ihh and VEGF with tumor size was statistically significant (PIhh and VEGF proteins in HCC (r=0.6, PIhh and CD34 staining (r=0.261, P=0.012). Our findings suggest that Ihh is involved in the development of HCC. These findings are also consistent with the concept that cooperation of Ihh and VEGF modulate HCC tumor angiogenesis and growth.

Hedgehog signaling contributes to basic fibroblast growth factor-regulated fibroblast migration

Energy Technology Data Exchange (ETDEWEB)

Zhu, Zhong Xin [School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, Zhejiang (China); Sun, Cong Cong [School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, Zhejiang (China); Wenzhou People' s Hospital, Wenzhou, Zhejiang (China); Ting Zhu, Yu; Wang, Ying; Wang, Tao; Chi, Li Sha; Cai, Wan Hui [School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, Zhejiang (China); Zheng, Jia Yong [Wenzhou People' s Hospital, Wenzhou, Zhejiang (China); Zhou, Xuan [Ningbo First Hospital, Ningbo, Zhejiang (China); Cong, Wei Tao [School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, Zhejiang (China); Li, Xiao Kun, E-mail: proflxk@163.com [School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, Zhejiang (China); Jin, Li Tai, E-mail: jin_litai@126.com [School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, Zhejiang (China)

2017-06-15

Fibroblast migration is a central process in skin wound healing, which requires the coordination of several types of growth factors. bFGF, a well-known fibroblast growth factor (FGF), is able to accelerate fibroblast migration; however, the underlying mechanism of bFGF regulation fibroblast migration remains unclear. Through the RNA-seq analysis, we had identified that the hedgehog (Hh) canonical pathway genes including Smoothened (Smo) and Gli1, were regulated by bFGF. Further analysis revealed that activation of the Hh pathway via up-regulation of Smo promoted fibroblast migration, invasion, and skin wound healing, but which significantly reduced by GANT61, a selective antagonist of Gli1/Gli2. Western blot analyses and siRNA transfection assays demonstrated that Smo acted upstream of phosphoinositide 3-kinase (PI3K)-c-Jun N-terminal kinase (JNK)-β-catenin to promote cell migration. Moreover, RNA-seq and qRT-PCR analyses revealed that Hh pathway genes including Smo and Gli1 were under control of β-catenin, suggesting that β-catenin turn feedback activates Hh signaling. Taken together, our analyses identified a new bFGF-regulating mechanism by which Hh signaling regulates human fibroblast migration, and the data presented here opens a new avenue for the wound healing therapy. - Highlights: • bFGF regulates Hedgehog (Hh) signaling in fibroblasts. • The Smo and Gli two master regulators of Hh signaling positively regulate fibroblast migration. • Smo facilitates β-catenin nuclear translocation via activation PI3K/JNK/GSK3β. • β-catenin positively regulates fibroblast cell migration and the expression of Hh signaling genes including Smo and Gli.

Hedgehog signaling contributes to basic fibroblast growth factor-regulated fibroblast migration

International Nuclear Information System (INIS)

Zhu, Zhong Xin; Sun, Cong Cong; Ting Zhu, Yu; Wang, Ying; Wang, Tao; Chi, Li Sha; Cai, Wan Hui; Zheng, Jia Yong; Zhou, Xuan; Cong, Wei Tao; Li, Xiao Kun; Jin, Li Tai

2017-01-01

Fibroblast migration is a central process in skin wound healing, which requires the coordination of several types of growth factors. bFGF, a well-known fibroblast growth factor (FGF), is able to accelerate fibroblast migration; however, the underlying mechanism of bFGF regulation fibroblast migration remains unclear. Through the RNA-seq analysis, we had identified that the hedgehog (Hh) canonical pathway genes including Smoothened (Smo) and Gli1, were regulated by bFGF. Further analysis revealed that activation of the Hh pathway via up-regulation of Smo promoted fibroblast migration, invasion, and skin wound healing, but which significantly reduced by GANT61, a selective antagonist of Gli1/Gli2. Western blot analyses and siRNA transfection assays demonstrated that Smo acted upstream of phosphoinositide 3-kinase (PI3K)-c-Jun N-terminal kinase (JNK)-β-catenin to promote cell migration. Moreover, RNA-seq and qRT-PCR analyses revealed that Hh pathway genes including Smo and Gli1 were under control of β-catenin, suggesting that β-catenin turn feedback activates Hh signaling. Taken together, our analyses identified a new bFGF-regulating mechanism by which Hh signaling regulates human fibroblast migration, and the data presented here opens a new avenue for the wound healing therapy. - Highlights: • bFGF regulates Hedgehog (Hh) signaling in fibroblasts. • The Smo and Gli two master regulators of Hh signaling positively regulate fibroblast migration. • Smo facilitates β-catenin nuclear translocation via activation PI3K/JNK/GSK3β. • β-catenin positively regulates fibroblast cell migration and the expression of Hh signaling genes including Smo and Gli.

Sonic hedgehog signaling regulates mode of cell division of early cerebral cortex progenitors and increases astrogliogenesis

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Geissy LL Araújo

2014-03-01

Full Text Available The morphogen Sonic Hedgehog (SHH plays a critical role in the development of different tissues. In the central nervous system, SHH is well known to contribute to the patterning of the spinal cord and separation of the brain hemispheres. In addition, it has recently been shown that SHH signaling also contributes to the patterning of the telencephalon and establishment of adult neurogenic niches. In this work, we investigated whether SHH signaling influences the behavior of neural progenitors isolated from the dorsal telencephalon, which generate excitatory neurons and macroglial cells in vitro. We observed that SHH increases proliferation of cortical progenitors and generation of astrocytes, whereas blocking SHH signaling with cyclopamine has opposite effects. In both cases, generation of neurons did not seem to be affected. However, cell survival was broadly affected by blockade of SHH signaling. SHH effects were related to three different cell phenomena: mode of cell division, cell cycle length and cell growth. Together, our data in vitro demonstrate that SHH signaling controls cell behaviors that are important for proliferation of cerebral cortex progenitors, as well as differentiation and survival of neurons and astroglial cells.

Improvement of Neutral Lipid and Polyunsaturated Fatty Acid Biosynthesis by Overexpressing a Type 2 Diacylglycerol Acyltransferase in Marine Diatom Phaeodactylum tricornutum

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Ying-Fang Niu

2013-11-01

Full Text Available Microalgae have been emerging as an important source for the production of bioactive compounds. Marine diatoms can store high amounts of lipid and grow quite quickly. However, the genetic and biochemical characteristics of fatty acid biosynthesis in diatoms remain unclear. Glycerophospholipids are integral as structural and functional components of cellular membranes, as well as precursors of various lipid mediators. In addition, diacylglycerol acyltransferase (DGAT is a key enzyme that catalyzes the last step of triacylglyceride (TAG biosynthesis. However, a comprehensive sequence-structure and functional analysis of DGAT in diatoms is lacking. In this study, an isoform of diacylglycerol acyltransferase type 2 of the marine diatom Phaeodactylum tricornutum was characterized. Surprisingly, DGAT2 overexpression in P. tricornutum stimulated more oil bodies, and the neutral lipid content increased by 35%. The fatty acid composition showed a significant increase in the proportion of polyunsaturated fatty acids; in particular, EPA was increased by 76.2%. Moreover, the growth rate of transgenic microalgae remained similar, thereby maintaining a high biomass. Our results suggest that increased DGAT2 expression could alter fatty acid profile in the diatom, and the results thus represent a valuable strategy for polyunsaturated fatty acid production by genetic manipulation.

Structure and function of lysosomal phospholipase A2 and lecithin:cholesterol acyltransferase

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Glukhova, Alisa; Hinkovska-Galcheva, Vania; Kelly, Robert; Abe, Akira; Shayman, James A.; Tesmer, John J. G.

2015-03-01

Lysosomal phospholipase A2 (LPLA2) and lecithin:cholesterol acyltransferase (LCAT) belong to a structurally uncharacterized family of key lipid-metabolizing enzymes responsible for lung surfactant catabolism and for reverse cholesterol transport, respectively. Whereas LPLA2 is predicted to underlie the development of drug-induced phospholipidosis, somatic mutations in LCAT cause fish eye disease and familial LCAT deficiency. Here we describe several high-resolution crystal structures of human LPLA2 and a low-resolution structure of LCAT that confirms its close structural relationship to LPLA2. Insertions in the α/β hydrolase core of LPLA2 form domains that are responsible for membrane interaction and binding the acyl chains and head groups of phospholipid substrates. The LCAT structure suggests the molecular basis underlying human disease for most of the known LCAT missense mutations, and paves the way for rational development of new therapeutics to treat LCAT deficiency, atherosclerosis and acute coronary syndrome.

Stereochemical and positional specificity of the lipase/acyltransferase produced by Aeromonas hydrophila.

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Robertson, D L; Hilton, S; Buckley, J T

1992-06-02

Aeromonas species secrete a glycerophospholipid-cholesterol acyltransferase (GCAT) which shares many properties with mammalian plasma lecithin-cholesterol acetyltransferase (LCAT). We have studied the stereochemical and positional specificity of GCAT against a variety of lipid substrates using NMR spectroscopy as well as other assay methods. The results show that both the primary and secondary acyl ester bonds of L-phosphatidylcholine can be hydrolyzed but only the sn-2 fatty acid can be transferred to cholesterol. The enzyme has an absolute requirement for the L configuration at the sn-2 position of phosphatidylcholine. The secondary ester bond of D-phosphatidylcholine cannot be hydrolyzed, and this lipid is not a substrate for acyl transfer. In contrast to the phospholipases, but similar to LCAT, the enzyme does not interact stereochemically with the phosphorus of phosphatidylcholine. In fact, the phosphorus is not required for enzyme activity, as GCAT will also hydrolyze monolayers of diglyceride, although at much lower rates.

Leukotriene synthesis is required for hedgehog-dependent neurite projection in neuralized embryoid bodies but not for motor neuron differentiation

NARCIS (Netherlands)

Bijlsma, Maarten F.; Peppelenbosch, Maikel P.; Spek, C. Arnold; Roelink, Henk

The hedgehog (Hh) pathway is required for many developmental processes,. as well as for adult homeostasis. Although all known effects of Hh signaling affecting patterning and differentiation are mediated by members of the Gli family of zinc ringer transcription factors, we demonstrate that the

Hedgehog signal activation coordinates proliferation and differentiation of fetal liver progenitor cells

International Nuclear Information System (INIS)

Hirose, Yoshikazu; Itoh, Tohru; Miyajima, Atsushi

2009-01-01

Hedgehog (Hh) signaling plays crucial roles in development and homeostasis of various organs. In the adult liver, it regulates proliferation and/or viability of several types of cells, particularly under injured conditions, and is also implicated in stem/progenitor cell maintenance. However, the role of this signaling pathway during the normal developmental process of the liver remains elusive. Although Sonic hedgehog (Shh) is expressed in the ventral foregut endoderm from which the liver derives, the expression disappears at the onset of the liver bud formation, and its possible recurrence at the later stages has not been investigated. Here we analyzed the activation and functional relevance of Hh signaling during the mouse fetal liver development. At E11.5, Shh and an activation marker gene for Hh signaling, Gli1, were expressed in Dlk + hepatoblasts, the fetal liver progenitor cells, and the expression was rapidly decreased thereafter as the development proceeded. In the culture of Dlk + hepatoblasts isolated from the E11.5 liver, activation of Hh signaling stimulated their proliferation and this effect was cancelled by a chemical Hh signaling inhibitor, cyclopamine. In contrast, hepatocyte differentiation of Dlk + hepatoblasts in vitro as manifested by the marker gene expression and acquisition of ammonia clearance activity was significantly inhibited by forced activation of Hh signaling. Taken together, these results demonstrate the temporally restricted manner of Hh signal activation and its role in promoting the hepatoblast proliferation, and further suggest that the pathway needs to be shut off for the subsequent hepatic differentiation of hepatoblasts to proceed normally.

Duplication of 7q36.3 encompassing the Sonic Hedgehog (SHH) gene is associated with congenital muscular hypertrophy

DEFF Research Database (Denmark)

Kristensen, Lone Krøldrup; Kjaergaard, S; Kirchhoff, Marianne

2012-01-01

with muscular hypertrophy and mildly retarded psychomotor development. Array-CGH identified a small duplication of 7q36.3 including the Sonic Hedgehog (SHH) gene in both the aborted foetus and the live born male sib. Neither of the parents carried the 7q36.3 duplication. The consequences of overexpression...

CXCL14 is a candidate biomarker for Hedgehog signalling in idiopathic pulmonary fibrosis.

Science.gov (United States)

Jia, Guiquan; Chandriani, Sanjay; Abbas, Alexander R; DePianto, Daryle J; N'Diaye, Elsa N; Yaylaoglu, Murat B; Moore, Heather M; Peng, Ivan; DeVoss, Jason; Collard, Harold R; Wolters, Paul J; Egen, Jackson G; Arron, Joseph R

2017-09-01

Idiopathic pulmonary fibrosis (IPF) is associated with aberrant expression of developmental pathways, including Hedgehog (Hh). As Hh signalling contributes to multiple pro-fibrotic processes, Hh inhibition may represent a therapeutic option for IPF. However, no non-invasive biomarkers are available to monitor lung Hh activity. We assessed gene and protein expression in IPF and control lung biopsies, mouse lung, fibroblasts stimulated in vitro with sonic hedgehog (SHh), and plasma in IPF patients versus controls, and cancer patients before and after treatment with vismodegib, a Hh inhibitor. Lung tissue from IPF patients exhibited significantly greater expression of Hh-related genes versus controls. The gene most significantly upregulated in both IPF lung biopsies and fibroblasts stimulated in vitro with SHh was CXCL14 , which encodes a soluble secreted chemokine whose expression is inhibited in vitro by the addition of vismodegib. CXCL14 expression was induced by SHh overexpression in mouse lung. Circulating CXCL14 protein levels were significantly higher in plasma from IPF patients than controls. In cancer patients, circulating CXCL14 levels were significantly reduced upon vismodegib treatment. CXCL14 is a systemic biomarker that could be used to identify IPF patients with increased Hh pathway activity and monitor the pharmacodynamic effects of Hh antagonist therapy in IPF. Post-results, NCT00968981. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Advanced basal cell carcinoma, the hedgehog pathway, and treatment options – role of smoothened inhibitors

Science.gov (United States)

Fecher, Leslie A; Sharfman, William H

2015-01-01

Cutaneous basal cell carcinoma (BCC) is the most common human cancer and its incidence is rising worldwide. Ultraviolet radiation exposure, including tanning bed use, as well as host factors play a role in its development. The majority of cases are treated and cured with local therapies including surgery. Yet, the health care costs of diagnosis and treatment of BCCs in the US is substantial. In the United States, the cost of nonmelanoma skin cancer care in the Medicare population is estimated to be US$426 million per year. While rare, locally advanced BCCs that can no longer be controlled with surgery and/or radiation, and metastatic BCCs do occur and can be associated with significant morbidity and mortality. Vismodegib (GDC-0449), a smoothened inhibitor targeted at the hedgehog pathway, is the first US Food and Drug Association (FDA)-approved agent in the treatment of locally advanced, unresectable, and metastatic BCCs. This class of agents appears to be changing the survival rates in advanced BCC patients, but appropriate patient selection and monitoring are important. Multidisciplinary assessments are essential for the optimal care and management of these patients. For some patients with locally advanced BCC, treatment with a hedgehog inhibitor may eliminate the need for an excessively disfiguring or morbid surgery. PMID:26604681

Lysophosphatidic acid activates peroxisome proliferator activated receptor-γ in CHO cells that over-express glycerol 3-phosphate acyltransferase-1.

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Cliona M Stapleton

2011-04-01

Full Text Available Lysophosphatidic acid (LPA is an agonist for peroxisome proliferator activated receptor-γ (PPARγ. Although glycerol-3-phosphate acyltransferase-1 (GPAT1 esterifies glycerol-3-phosphate to form LPA, an intermediate in the de novo synthesis of glycerolipids, it has been assumed that LPA synthesized by this route does not have a signaling role. The availability of Chinese Hamster Ovary (CHO cells that stably overexpress GPAT1, allowed us to analyze PPARγ activation in the presence of LPA produced as an intracellular intermediate. LPA levels in CHO-GPAT1 cells were 6-fold higher than in wild-type CHO cells, and the mRNA abundance of CD36, a PPARγ target, was 2-fold higher. Transactivation assays showed that PPARγ activity was higher in the cells that overexpressed GPAT1. PPARγ activity was enhanced further in CHO-GPAT1 cells treated with the PPARγ ligand troglitazone. Extracellular LPA, phosphatidic acid (PA or a membrane-permeable diacylglycerol had no effect, showing that PPARγ had been activated by LPA generated intracellularly. Transient transfection of a vector expressing 1-acylglycerol-3-phosphate acyltransferase-2, which converts endogenous LPA to PA, markedly reduced PPARγ activity, as did over-expressing diacylglycerol kinase, which converts DAG to PA, indicating that PA could be a potent inhibitor of PPARγ. These data suggest that LPA synthesized via the glycerol-3-phosphate pathway can activate PPARγ and that intermediates of de novo glycerolipid synthesis regulate gene expression.

Indian hedgehog contributes to human cartilage endplate degeneration.

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Wang, Shaowei; Yang, Kun; Chen, Shuai; Wang, Jiying; Du, Guoqing; Fan, Shunwu; Wei, Lei

2015-08-01

To determine the role of Indian hedgehog (Ihh) signaling in human cartilage endplate (CEP) degeneration. CEP-degenerated tissues from patients with Modic I or II changes (n = 9 and 45, respectively) and normal tissues from vertebral burst fracture patients (n = 17) were collected. Specimens were either cut into slices for organ culture ex vivo or digested to isolate chondrocytes for cell culture in vitro. Ihh expression and the effect of Ihh on cartilage degeneration were determined by investigating degeneration markers in this study. Ihh expression and cartilage degeneration markers significantly increased in the Modic I and II groups. The expression of cartilage degeneration markers was positively correlated with degeneration severity. Gain-of-function for Ihh promoted expression of cartilage degeneration markers in vitro, while loss-of-function for Ihh inhibited their expression both in vitro and ex vivo. These findings demonstrated that Ihh promotes CEP degeneration. Blocking Ihh pathway has potential clinical usage for attenuating CEP degeneration.

Acquisition of 5-fluorouracil resistance induces epithelial-mesenchymal transitions through the Hedgehog signaling pathway in HCT-8 colon cancer cells.

Science.gov (United States)

Liu, Yanjun; DU, Fangfang; Zhao, Qiannan; Jin, Jian; Ma, Xin; Li, Huazhong

2015-06-01

Colon cancer has a high incidence in individuals >60-years-old. The commonly used chemotherapeutic agent, 5-fluorouracil (5-FU), has gradually lost its potency in treating colorectal cancer following the acquisition of resistance. Drug resistance is usually associated with epithelial-mesenchymal transitions (EMTs) in cancer cells. In the present study, the EMT phenotypes of two colon cancer cell lines, wild-type (HCT-8/WT) and 5-FU-resistant (HCT-8/5-FU), were characterized following the analysis of cellular migration, proliferation, morphology and molecular changes. In order to further clarify the mechanism of EMT in HCT-8/5-FU cells, the effect of EMT pathway inhibitors upon drug sensitivity was investigated. The results revealed that the Hedgehog signaling pathway inhibitor, GDC0449, reversed drug resistance. Therefore, inhibition of the Hedgehog pathway may provide a novel chemotherapeutic strategy for the treatment of patients with 5-FU-resistant colon cancer.

Augmented Indian hedgehog signaling in cranial neural crest cells leads to craniofacial abnormalities and dysplastic temporomandibular joint in mice.

Science.gov (United States)

Yang, Ling; Gu, Shuping; Ye, Wenduo; Song, Yingnan; Chen, YiPing

2016-04-01

Extensive studies have pinpointed the crucial role of Indian hedgehog (Ihh) signaling in the development of the appendicular skeleton and the essential function of Ihh in the formation of the temporomandibular joint (TMJ). In this study, we have investigated the effect of augmented Ihh signaling in TMJ development. We took a transgenic gain-of-function approach by overexpressing Ihh in the cranial neural crest (CNC) cells using a conditional Ihh transgenic allele and the Wnt1-Cre allele. We found that Wnt1-Cre-mediated tissue-specific overexpression of Ihh in the CNC lineage caused severe craniofacial abnormalities, including cleft lip/palate, encephalocele, anophthalmos, micrognathia, and defective TMJ development. In the mutant TMJ, the glenoid fossa was completely absent, whereas the condyle and the articular disc appeared relatively normal with slightly delayed chondrocyte differentiation. Our findings thus demonstrate that augmented Ihh signaling is detrimental to craniofacial development, and that finely tuned Ihh signaling is critical for TMJ formation. Our results also provide additional evidence that the development of the condyle and articular disc is independent of the glenoid fossa.

Generalidades de la señalización molecular durante el desarrollo embrionario: El caso del Sonic Hedgehog

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David Arias

2016-12-01

Full Text Available Histogenesis and organogenesis of the vertebrates –including humans– involves the interaction of an epithelium (derived from the ectoderm and endoderm and the underlying mesenchyme (derived from the intraembryonic mesoderm. This interaction is regulated by a paracrine signaling network that includes several ligands and their respective receptors, in addition to a series of transcription factors that control the whole system. Among these factors are fibroblast growth factors (Fgf, Hedgehog family (Hh, Wingless family (Wnt and beta-fibroblast growth factor superfamily (Tgf-β, which act to organize the morphogenetic pattern of a tissue, an organ, an apparatus and a morphofunctional system. One of the most studied factors is Sonic hedgehog (Shh, which is essential for regulating the formation of morphogenetic fields in specific places of the embryo’s body schema through cell proliferation, differentiation, migration and cell survival processes –in development or in the adult–. Therefore, the purpose of this literature review is to describe the role of Shh in the embryonic development of the neural tube, the limbs and the teeth.

Sonic hedgehog stimulates the proliferation of rat gastric mucosal cells through ERK activation by elevating intracellular calcium concentration

International Nuclear Information System (INIS)

Osawa, Hiroyuki; Ohnishi, Hirohide; Takano, Koji; Noguti, Takasi; Mashima, Hirosato; Hoshino, Hiroko; Kita, Hiroto; Sato, Kiichi; Matsui, Hirofumi; Sugano, Kentaro

2006-01-01

Sonic Hedgehog (Shh), a member of hedgehog peptides family, is expressed in gastric gland epithelium. To elucidate Shh function to gastric mucosal cells, we examined the effect of Shh on the proliferation of a rat normal gastric mucosal cell line, RGM-1. RGM-1 cells express essential components of Shh receptor system, patched-1, and smoothened. Shh enhanced DNA synthesis in RGM-1 cells and elevated intracellular calcium concentration ([Ca 2+ ] i ). In addition, Shh as well as calcium ionophore A32187 rapidly activated ERK. However, Shh failed to activate ERK under calcium-free culture condition. Pretreatment of cells with PD98059 attenuated the DNA synthesis promoted by Shh. Moreover, when cells were pretreated with cyclopamine, Shh could not elevate [Ca 2+ ] i , activate ERK or promote DNA synthesis. On the other hand, although Shh induced Gli-1 nuclear accumulation in RGM-1 cells, Shh activated ERK even in cells pretreated with actinomycin D. These results indicate that Shh promotes the proliferation of RGM-1 cells through an intracellular calcium- and ERK-dependent but transcription-independent pathway via Patched/Smoothened receptor system

The role of the Hedgehog signaling pathway in cancer: A comprehensive review

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Ana Marija Skoda

2018-02-01

Full Text Available The Hedgehog (Hh signaling pathway was first identified in the common fruit fly. It is a highly conserved evolutionary pathway of signal transmission from the cell membrane to the nucleus. The Hh signaling pathway plays an important role in the embryonic development. It exerts its biological effects through a signaling cascade that culminates in a change of balance between activator and repressor forms of glioma-associated oncogene (Gli transcription factors. The components of the Hh signaling pathway involved in the signaling transfer to the Gli transcription factors include Hedgehog ligands (Sonic Hh [SHh], Indian Hh [IHh], and Desert Hh [DHh], Patched receptor (Ptch1, Ptch2, Smoothened receptor (Smo, Suppressor of fused homolog (Sufu, kinesin protein Kif7, protein kinase A (PKA, and cyclic adenosine monophosphate (cAMP. The activator form of Gli travels to the nucleus and stimulates the transcription of the target genes by binding to their promoters. The main target genes of the Hh signaling pathway are PTCH1, PTCH2, and GLI1. Deregulation of the Hh signaling pathway is associated with developmental anomalies and cancer, including Gorlin syndrome, and sporadic cancers, such as basal cell carcinoma, medulloblastoma, pancreatic, breast, colon, ovarian, and small-cell lung carcinomas. The aberrant activation of the Hh signaling pathway is caused by mutations in the related genes (ligand-independent signaling or by the excessive expression of the Hh signaling molecules (ligand-dependent signaling – autocrine or paracrine. Several Hh signaling pathway inhibitors, such as vismodegib and sonidegib, have been developed for cancer treatment. These drugs are regarded as promising cancer therapies, especially for patients with refractory/advanced cancers.

Co-ordinate induction of hepatic mitochondrial and peroxisomal carnitine acyltransferase synthesis by diet and drugs.

Science.gov (United States)

Brady, P S; Marine, K A; Brady, L J; Ramsay, R R

1989-01-01

The present studies examined the effect of agents that induce peroxisomal and mitochondrial beta-oxidation on hepatic mitochondrial carnitine palmitoyltransferase (CPT) and peroxisomal carnitine acyltransferase [CPTs of Ramsay (1988) Biochem. J. 249, 239-245; COT of Farrell & Bieber (1983) Arch. Biochem. Biophys. 222, 123-132 and Miyazawa, Ozasa, Osumi & Hashimoto (1983) J. Biochem. 94, 529-542]. In the first studies, high fat diets containing corn oil or fish oil were used to induce peroxisomal and mitochondrial enzymes. Rats were fed one of three diets for 4 weeks: (1) low fat, with corn oil as 11% of energy (kJ); (2) high fat, with corn oil as 45% of kJ; (3) high fat, with fish oil as 45% of kJ. At the end of 4 weeks, both mitochondrial CPT and peroxisomal CPTs exhibited increases in activity, immunoreactive protein, mRNA levels and transcription rates in livers of rats fed either high-fat diet compared to the low fat diet. Riboflavin deficiency or starvation for 48 h also increased the peroxisomal CPTs mRNA. A second set of studies used the plasticizer 2-(diethylhexyl)phthalate (DEHP), 0.5% clofibrate or 1% acetylsalicylic acid (fed for 3 weeks) to alter peroxisomal and mitochondrial fatty acid oxidation. With DEHP, the mitochondrial CPT and peroxisomal CPTs activity, immunoreactive protein, mRNA levels and and transcription rate were all increased by 3-5-fold. The peroxisomal CPTs activity, immunoreactive protein, mRNA levels and transcription rate were increased 2-3-fold by clofibrate and acetylsalicylic acid, again similar to mitochondrial CPT. The results of the combined studies using both diet and drugs to cause enzyme induction suggest that the synthesis of the carnitine acyltransferases (mitochondrial CPT and peroxisomal CPTs) may be co-ordinated with each other; however, the co-ordinate regulatory factors have not yet been identified. Images Fig. 1. Fig. 2. Fig. 3. Fig. 4. Fig. 5. PMID:2775196

Identification and Characterization of KCASH2 and KCASH3, 2 Novel Cullin3 Adaptors Suppressing Histone Deacetylase and Hedgehog Activity in Medulloblastoma

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Enrico De Smaele

2011-04-01

Full Text Available Medulloblastoma is the most common pediatric malignant brain tumor, arising from aberrant cerebellar precursors' development, a process mainly controlled by Hedgehog (Hh signaling pathway. Histone deacetylase HDAC1 has been recently shown to modulate Hh signaling, deacetylating its effectors Gli1/2 and enhancing their transcriptional activity. Therefore, HDAC may represent a potential therapeutic target for Hh-dependent tumors, but still little information is available on the physiological mechanisms of HDAC regulation. The putative tumor suppressor RENKCTD11 acts through ubiquitination-dependent degradation of HDAC1, thereby affecting Hh activity and medulloblastoma growth. We identify and characterize here two RENKCTD11 homologues, defining a new family of proteins named KCASH, as “KCTD containing, Cullin3 adaptor, suppressor of Hedgehog.” Indeed, the novel genes (KCASH2KCTD21 and KCASH3KCTD6 share with RENKCTD11 a number of features, such as a BTB domain required for the formation of a Cullin3 ubiquitin ligase complex and HDAC1 ubiquitination and degradation capability, suppressing the acetylation-dependent Hh/Gli signaling. Expression of KCASH2 and -3 is observed in cerebellum, whereas epigenetic silencing and allelic deletion are observed in human medulloblastoma. Rescuing KCASHs expression reduces the Hedgehog-dependent medulloblastoma growth, suggesting that loss of members of this novel family of native HDAC inhibitors is crucial in sustaining Hh pathway-mediated tumorigenesis. Accordingly, they might represent a promising class of endogenous “agents” through which this pathway may be targeted.

Identification and Characterization of Diacylglycerol Acyltransferase from Oleaginous Fungus Mucor circinelloides.

Science.gov (United States)

Zhang, Luning; Zhang, Huaiyuan; Song, Yuanda

2018-01-24

Acyl-CoA:diacylglycerol acyltransferase (DGAT) is a pivotal regulator of triacylglycerol (TAG) synthesis. The oleaginous fungus Mucor circinelloides has four putative DGATs: McDGAT1A, McDGAT1B, McDGAT2A, and McDGAT2B, classified into the DGAT1 and DGAT2 subfamilies, respectively. To identify and characterize DGATs in M. circinelloides, these four genes were expressed in Saccharomyces cerevisiae H1246 (TAG-deficient quadruple mutant), individually. TAG biosynthesis was restored only by the expression of McDGAT2B, and TAG content was significantly higher in the mutants with McDGAT2B expression than in a S. cerevisiae mutant with endogenous DGA1 expression. McDGAT2B prefers saturated fatty acids to monounsaturated fatty acids and has an obvious preference for C18:3 (ω-6) according to the results of substrate preference experiments. Furthermore, only the mRNA expression pattern of McDGAT2B correlated with TAG biosynthesis during a fermentation process. Our experiments strongly indicate that McDGAT2B is crucial for TAG accumulation, suggesting that it may be an essential target for metabolic engineering aimed at increasing lipid content of M. circinelloides.

Hedgehog signaling: endocrine gland development and function.

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Cohen, M Michael

2010-01-01

The role of hedgehog signaling is analyzed in relation to the developing endocrine glands: pituitary, ovary, testis, adrenal cortex, pancreas, prostate, and epiphyseal growth. Experimental and pathological correlates of these organs are also discussed. The second section addresses a number of topics. First, the pituitary gland, no matter how hypoplastic, is present in most cases of human holoprosencephaly, unlike animals in which it is always said to be absent. The difference appears to be that animal mutations and teratogenic models involve both copies of the gene in question, whereas in humans the condition is most commonly heterozygous. Second, tests of endocrine function are not reported with great frequency, and an early demise in severe cases of holoprosencephaly accounts for this trend. Reported tests of endocrine function are reviewed. Third, diabetes insipidus has been recorded in a number of cases of holoprosencephaly. Its frequency is unknown because it could be masked by adrenal insufficiency in some cases and may not be recognized in others. Because of the abnormal hypothalamic-infundibular region in holoprosencephaly, diabetes insipidus could be caused by a defect in the supra-optic or paraventricular hypothalamic nuclei or in release of ADH via the infundibulum and posterior pituitary.

Regulator of G-protein signaling - 5 (RGS5 is a novel repressor of hedgehog signaling.

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William M Mahoney

Full Text Available Hedgehog (Hh signaling plays fundamental roles in morphogenesis, tissue repair, and human disease. Initiation of Hh signaling is controlled by the interaction of two multipass membrane proteins, patched (Ptc and smoothened (Smo. Recent studies identify Smo as a G-protein coupled receptor (GPCR-like protein that signals through large G-protein complexes which contain the Gαi subunit. We hypothesize Regulator of G-Protein Signaling (RGS proteins, and specifically RGS5, are endogenous repressors of Hh signaling via their ability to act as GTPase activating proteins (GAPs for GTP-bound Gαi, downstream of Smo. In support of this hypothesis, we demonstrate that RGS5 over-expression inhibits sonic hedgehog (Shh-mediated signaling and osteogenesis in C3H10T1/2 cells. Conversely, signaling is potentiated by siRNA-mediated knock-down of RGS5 expression, but not RGS4 expression. Furthermore, using immuohistochemical analysis and co-immunoprecipitation (Co-IP, we demonstrate that RGS5 is present with Smo in primary cilia. This organelle is required for canonical Hh signaling in mammalian cells, and RGS5 is found in a physical complex with Smo in these cells. We therefore conclude that RGS5 is an endogenous regulator of Hh-mediated signaling and that RGS proteins are potential targets for novel therapeutics in Hh-mediated diseases.

Phylogenetic analysis of glycerol 3-phosphate acyltransferases in opisthokonts reveals unexpected ancestral complexity and novel modern biosynthetic components.

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Heather C Smart

Full Text Available Glycerolipid synthesis represents a central metabolic process of all forms of life. In the last decade multiple genes coding for enzymes responsible for the first step of the pathway, catalyzed by glycerol 3-phosphate acyltransferase (GPAT, have been described, and characterized primarily in model organisms like Saccharomyces cerevisiae and mice. Notoriously, the fungal enzymes share low sequence identity with their known animal counterparts, and the nature of their homology is unclear. Furthermore, two mitochondrial GPAT isoforms have been described in animal cells, while no such enzymes have been identified in Fungi. In order to determine if the yeast and mammalian GPATs are representative of the set of enzymes present in their respective groups, and to test the hypothesis that metazoan orthologues are indeed absent from the fungal clade, a comparative genomic and phylogenetic analysis was performed including organisms spanning the breadth of the Opisthokonta supergroup. Surprisingly, our study unveiled the presence of 'fungal' orthologs in the basal taxa of the holozoa and 'animal' orthologues in the basal holomycetes. This includes a novel clade of fungal homologues, with putative peroxisomal targeting signals, of the mitochondrial/peroxisomal acyltransferases in Metazoa, thus potentially representing an undescribed metabolic capacity in the Fungi. The overall distribution of GPAT homologues is suggestive of high relative complexity in the ancestors of the opisthokont clade, followed by loss and sculpting of the complement in the descendent lineages. Divergence from a general versatile metabolic model, present in ancestrally deduced GPAT complements, points to distinctive contributions of each GPAT isoform to lipid metabolism and homeostasis in contemporary organisms like humans and their fungal pathogens.

Subcellular Localization of Patched and Smoothened, the Receptors for Sonic Hedgehog Signaling, in the Hippocampal Neuron

OpenAIRE

Petralia, Ronald S.; Schwartz, Catherine M.; Wang, Ya-Xian; Mattson, Mark P.; Yao, Pamela J.

2011-01-01

Cumulative evidence suggests that, aside from patterning the embryonic neural tube, Sonic hedgehog (Shh) signaling plays important roles in the mature nervous system. In this study, we investigate the expression and localization of the Shh signaling receptors, Patched (Ptch) and Smoothened (Smo), in the hippocampal neurons of young and mature rats. Reverse transcriptase-polymerase chain reaction and immunoblotting analyses show that the expression of Ptch and Smo remains at a moderate level i...

Sonic hedgehog signaling inhibition provides opportunities for targeted therapy by sulforaphane in regulating pancreatic cancer stem cell self-renewal.

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Mariana Rodova

Full Text Available Dysregulation of the sonic hedgehog (Shh signaling pathway has been associated with cancer stem cells (CSC and implicated in the initiation of pancreatic cancer. Pancreatic CSCs are rare tumor cells characterized by their ability to self-renew, and are responsible for tumor recurrence accompanied by resistance to current therapies. The lethality of these incurable, aggressive and invasive pancreatic tumors remains a daunting clinical challenge. Thus, the objective of this study was to investigate the role of Shh pathway in pancreatic cancer and to examine the molecular mechanisms by which sulforaphane (SFN, an active compound in cruciferous vegetables, inhibits self-renewal capacity of human pancreatic CSCs. Interestingly, we demonstrate here that Shh pathway is highly activated in pancreatic CSCs and plays important role in maintaining stemness by regulating the expression of stemness genes. Given the requirement for Hedgehog in pancreatic cancer, we investigated whether hedgehog blockade by SFN could target the stem cell population in pancreatic cancer. In an in vitro model, human pancreatic CSCs derived spheres were significantly inhibited on treatment with SFN, suggesting the clonogenic depletion of the CSCs. Interestingly, SFN inhibited the components of Shh pathway and Gli transcriptional activity. Interference of Shh-Gli signaling significantly blocked SFN-induced inhibitory effects demonstrating the requirement of an active pathway for the growth of pancreatic CSCs. SFN also inhibited downstream targets of Gli transcription by suppressing the expression of pluripotency maintaining factors (Nanog and Oct-4 as well as PDGFRα and Cyclin D1. Furthermore, SFN induced apoptosis by inhibition of BCL-2 and activation of caspases. Our data reveal the essential role of Shh-Gli signaling in controlling the characteristics of pancreatic CSCs. We propose that pancreatic cancer preventative effects of SFN may result from inhibition of the Shh pathway

Hedgehog signaling activation induces stem cell proliferation and hormone release in the adult pituitary gland

OpenAIRE

Joanna Pyczek; Rolf Buslei; David Schult; Annett Hölsken; Michael Buchfelder; Ina Heß; Heidi Hahn; Anja Uhmann

2016-01-01

Hedgehog (HH) signaling is known to be essential during the embryonal development of the pituitary gland but the knowledge about its role in the adult pituitary and in associated tumors is sparse. In this report we investigated the effect of excess Hh signaling activation in murine pituitary explants and analyzed the HH signaling status of human adenopituitary lobes and a large cohort of pituitary adenomas. Our data show that excess Hh signaling led to increased proliferation of Sox2(+) and S...

[Effect of hedgehog hydnum on the delay of fatigue in mice].

Science.gov (United States)

Lu, Y H; Xin, C L; Zhou, Y F; Liu, X W; Chi, J W; Chang, X

1996-02-01

Two groups of mice were fed with either hedgehog hydnum powder or extract for sixty days. For the assay of fatigue, the activity of serum lactate dehydrogenase, the serum urea nitrogen content, blood lactic acid, hepatic and muscular glycogen, and the physical stamina of the mice were determined. The activity of serum lactate dehydrogenase and the hepatic and muscular glycogen content in the experimental mice were evidently higher than that in the control mice (P increase in blood lactic acid and serum urea nitrogen in the experimental mice was significantly lower than that in the control mice (P stamina swimming, the experimental mice drowned after a longer period of time than the control mice (P stamina and delaying fatigue in mice.

Evolutionary genomics and adaptive evolution of the hedgehog gene family (Shh, Ihh and Dhh) in vertebrates

DEFF Research Database (Denmark)

Pereira, Joana; Johnson, Warren E.; O'Brien, Stephen J.

2014-01-01

The Hedgehog (Hh) gene family codes for a class of secreted proteins composed of two active domains that act as signalling molecules during embryo development, namely for the development of the nervous and skeletal systems and the formation of the testis cord. While only one Hh gene is found typi...

Sonic Hedgehog Signaling in Thyroid Cancer

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Xiulong Xu

2017-10-01

Full Text Available Thyroid cancer is the most common malignancy of the endocrine system. The initiation of thyroid cancer is often triggered by a genetic mutation in the phosphortidylinositol-3 kinase (PI3K or mitogen-activated protein kinase (MAPK pathway, such as RAS and BRAF, or by the rearrangement of growth factor receptor tyrosine kinase genes such as RET/PTC. The sonic hedgehog (Shh pathway is evolutionarily conserved and plays an important role in the embryonic development of normal tissues and organs. Gene mutations in the Shh pathway are involved in basal cell carcinomas (BCC. Activation of the Shh pathway due to overexpression of the genes encoding the components of this pathway stimulates the growth and spread of a wide range of cancer types. The Shh pathway also plays an important role in cancer stem cell (CSC self-renewal. GDC-0449 and LDE-225, two inhibitors of this pathway, have been approved for treating BCC and are being tested as a single agent or in combination with other drugs for treating various other cancers. Here, we review the recent findings on activation of the Shh pathway in thyroid cancer and its role in maintaining thyroid CSC self-renewal. We also summarize the recent developments on crosstalk of the Shh pathway with the MAPK and PI3K oncogenic pathways, and its implications for combination therapy.

Sonic Hedgehog Signaling in Thyroid Cancer

Science.gov (United States)

Xu, Xiulong; Lu, Yurong; Li, Yi; Prinz, Richard A.

2017-01-01

Thyroid cancer is the most common malignancy of the endocrine system. The initiation of thyroid cancer is often triggered by a genetic mutation in the phosphortidylinositol-3 kinase (PI3K) or mitogen-activated protein kinase (MAPK) pathway, such as RAS and BRAF, or by the rearrangement of growth factor receptor tyrosine kinase genes such as RET/PTC. The sonic hedgehog (Shh) pathway is evolutionarily conserved and plays an important role in the embryonic development of normal tissues and organs. Gene mutations in the Shh pathway are involved in basal cell carcinomas (BCC). Activation of the Shh pathway due to overexpression of the genes encoding the components of this pathway stimulates the growth and spread of a wide range of cancer types. The Shh pathway also plays an important role in cancer stem cell (CSC) self-renewal. GDC-0449 and LDE-225, two inhibitors of this pathway, have been approved for treating BCC and are being tested as a single agent or in combination with other drugs for treating various other cancers. Here, we review the recent findings on activation of the Shh pathway in thyroid cancer and its role in maintaining thyroid CSC self-renewal. We also summarize the recent developments on crosstalk of the Shh pathway with the MAPK and PI3K oncogenic pathways, and its implications for combination therapy. PMID:29163356

Aberrant expression of sonic hedgehog pathway in colon cancer and melanosis coli.

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Wang, Zhong Chuan; Gao, Jun; Zi, Shu Ming; Yang, Ming; Du, Peng; Cui, Long

2013-08-01

To determine the hedgehog (Hh) signaling pathway correlated with the development of colon cancer and melanosis coli. Protein and mRNA levels of Hh signaling pathway components (sonic hedgehog [Shh], protein patched homolog 1 [Ptch 1], GLI family zinc finger 1 [Gli 1] and suppressor of fused homolog [Drosophila] [Sufu]) in 127 patients with colon cancer, 36 with melanosis coli and 20 adjacent normal mucosal tissues taken from surgical specimens were evaluated using antibody staining and quantitative real-time polymerase chain reaction. In adjacent normal tissue Shh and Ptch1, but not Gli1 or Sufu, were weakly expressed and mainly in the lining epithelium of the colonic mucosa. In cancerous tissues Shh and Gli1 were uniformly strong while Ptch1 was patchy and weak, and Sufu uniformly weak, which paralleled their levels of corresponding mRNA. Elevated protein levels of Shh and Ptch were significantly associated with mucinous colonic tissues. Elevated Sufu protein levels were positively correlated with the diameter and invasion of the tumor. In patients with melanosis coli, mRNA levels of Shh, Ptch1, Gli1 and Sufu were very low, which was similar to those of adjacent normal tissues; but protein levels of Shh, Ptch1 and Gli1, but not Sufu, were high, which was similar to those of cancerous tissues. The mRNA and protein levels of Hh pathway components are aberrantly elevated in colon cancer, which may be the potential molecular classification markers. Further studies are required to determine the role of melanosis coli in the colon tumorigenesis. © 2013 The Authors. Journal of Digestive Diseases © 2013 Wiley Publishing Asia Pty Ltd and Chinese Medical Association Shanghai Branch, Chinese Society of Gastroenterology, Renji Hospital Affiliated to Shanghai Jiaotong University School of Medicine.

Celiac Disease Histopathology Recapitulates Hedgehog Downregulation, Consistent with Wound Healing Processes Activation.

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Stefania Senger

Full Text Available In celiac disease (CD, intestinal epithelium damage occurs secondary to an immune insult and is characterized by blunting of the villi and crypt hyperplasia. Similarities between Hedgehog (Hh/BMP4 downregulation, as reported in a mouse model, and CD histopathology, suggest mechanistic involvement of Hh/BMP4/WNT pathways in proliferation and differentiation of immature epithelial cells in the context of human intestinal homeostasis and regeneration after damage. Herein we examined the nature of intestinal crypt hyperplasia and involvement of Hh/BMP4 in CD histopathology.Immunohistochemistry, qPCR and in situ hybridization were used to study a cohort of 24 healthy controls (HC and 24 patients with diagnosed acute celiac disease (A-CD intestinal biopsies. In A-CD we observed an increase in cells positive for Leucin-rich repeat-containing G protein-coupled receptor 5 (LGR5, an epithelial stem cell specific marker and expansion of WNT responding compartment. Further, we observed alteration in number and distribution of mesenchymal cells, predicted to be part of the intestinal stem cells niche. At the molecular level we found downregulation of indian hedgehog (IHH and other components of the Hh pathway, but we did not observe a concurrent downregulation of BMP4. However, we observed upregulation of BMPs antagonists, gremlin 1 and gremlin 2.Our data suggest that acute CD histopathology partially recapitulates the phenotype reported in Hh knockdown models. Specifically, Hh/BMP4 paradigm appears to be decoupled in CD, as the expansion of the immature cell population does not occur consequent to downregulation of BMP4. Instead, we provide evidence that upregulation of BMP antagonists play a key role in intestinal crypt hyperplasia. This study sheds light on the molecular mechanisms underlying CD histopathology and the limitations in the use of mouse models for celiac disease.

Overlapping activities of TGF-β and Hedgehog signaling in cancer: therapeutic targets for cancer treatment.

Science.gov (United States)

Perrot, Carole Y; Javelaud, Delphine; Mauviel, Alain

2013-02-01

Recent advances in the field of cancer therapeutics come from the development of drugs that specifically recognize validated oncogenic or pro-metastatic targets. The latter may be mutated proteins with altered function, such as kinases that become constitutively active, or critical components of growth factor signaling pathways, whose deregulation leads to aberrant malignant cell proliferation and dissemination to metastatic sites. We herein focus on the description of the overlapping activities of two important developmental pathways often exacerbated in cancer, namely Transforming Growth Factor-β (TGF-β) and Hedgehog (HH) signaling, with a special emphasis on the unifying oncogenic role played by GLI1/2 transcription factors. The latter are the main effectors of the canonical HH pathway, yet are direct target genes of TGF-β/SMAD signal transduction. While tumor-suppressor in healthy and pre-malignant tissues, TGF-β is often expressed at high levels in tumors and contributes to tumor growth, escape from immune surveillance, invasion and metastasis. HH signaling regulates cell proliferation, differentiation and apoptosis, and aberrant HH signaling is found in a variety of cancers. We discuss the current knowledge on HH and TGF-β implication in cancer including cancer stem cell biology, as well as the current state, both successes and failures, of targeted therapeutics aimed at blocking either of these pathways in the pre-clinical and clinical settings. Copyright © 2012 Elsevier Inc. All rights reserved.

Neuronal plasticity in the hedgehog supraoptic nucleus during hibernation.

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Sanchez-Toscano, F; Caminero, A A; Machin, C; Abella, G

1989-01-01

The purpose of the present study was to identify processes of plasticity in the receptive field of neurosecretory neurons of the supraoptic nucleus during hibernation in the hedgehog, in order to correlate them with the increased neurosecretory activity observed in this nucleus during this annual period. Using the Rapid Golgi method, a quantitative study was conducted in the receptive field of bipolar and multipolar neurons (the main components of the nucleus). Results indicate a generalized increase in the following characteristics: (1) number of dendritic spines per millimeter along the dendritic shafts; (2) degree of branching in the dendritic field; and (3) dendritic density around the neuronal soma. These data demonstrate modification of the dendritic field in the supraoptic nucleus during hibernation, a change undoubtedly related to functional conditions. Since the observed changes affect structures such as dendritic spines which are directly related to the arrival of neural afferences, the discussion is centered on the types of stimuli which may be responsible for the observed processes.

Osteocalcin expressing cells from tendon sheaths in mice contribute to tendon repair by activating Hedgehog signaling

OpenAIRE

Wang, Yi; Zhang, Xu; Huang, Huihui; Xia, Yin; Yao, YiFei; Mak, Arthur Fuk-Tat; Yung, Patrick Shu-Hang; Chan, Kai-Ming; Wang, Li; Zhang, Chenglin; Huang, Yu; Mak, Kingston King-Lun

2017-01-01

Both extrinsic and intrinsic tissues contribute to tendon repair, but the origin and molecular functions of extrinsic tissues in tendon repair are not fully understood. Here we show that tendon sheath cells harbor stem/progenitor cell properties and contribute to tendon repair by activating Hedgehog signaling. We found that Osteocalcin (Bglap) can be used as an adult tendon-sheath-specific marker in mice. Lineage tracing experiments show that Bglap-expressing cells in adult sheath tissues pos...

Lysophosphatidic acid acyltransferase beta regulates mTOR signaling.

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Michelle A Blaskovich

Full Text Available Lysophosphatidic acid acyltransferase (LPAAT-β is a phosphatidic acid (PA generating enzyme that plays an essential role in triglyceride synthesis. However, LPAAT-β is now being studied as an important regulator of cell growth and differentiation and as a potential therapeutic target in cancer since PA is necessary for the activity of key proteins such as Raf, PKC-ζ and mTOR. In this report we determine the effect of LPAAT-β silencing with siRNA in pancreatic adenocarcinoma cell lines. We show for the first time that LPAAT-β knockdown inhibits proliferation and anchorage-independent growth of pancreatic cancer cells. This is associated with inhibition of signaling by mTOR as determined by levels of mTORC1- and mTORC2-specific phosphorylation sites on 4E-BP1, S6K and Akt. Since PA regulates the activity of mTOR by modulating its binding to FKBP38, we explored the possibility that LPAAT-β might regulate mTOR by affecting its association with FKBP38. Coimmunoprecipitation studies of FKBP38 with mTOR show increased levels of FKBP38 associated with mTOR when LPAAT-β protein levels are knocked down. Furthermore, depletion of LPAAT-β results in increased Lipin 1 nuclear localization which is associated with increased nuclear eccentricity, a nuclear shape change that is dependent on mTOR, further confirming the ability of LPAAT-β to regulate mTOR function. Our results provide support for the hypothesis that PA generated by LPAAT-β regulates mTOR signaling. We discuss the implications of these findings for using LPAAT-β as a therapeutic target.

Instability of the hedgehog shape for the octet baryon in the chiral quark soliton model

OpenAIRE

Akiyama, Satoru; Futami, Yasuhiko

2003-01-01

In this paper the stability of the hedgehog shape of the chiral soliton is studied for the octet baryon with the SU(3) chiral quark soliton model. The strangeness degrees of freedom are treated by a simplified bound-state approach, which omits the locality of the kaon wave function. The mean field approximation for the flavor rotation is applied to the model. The classical soliton changes shape according to the strangeness. The baryon appears as a rotational band of the combined system of the...

Neocortical layers I and II of the hedgehog (Erinaceus europaeus). I. Intrinsic organization.

Science.gov (United States)

Valverde, F; Facal-Valverde, M V

1986-01-01

The intrinsic organization and interlaminar connections in neocortical layers I and II have been studied in adult hedgehogs (Erinaceus europaeus) using the Golgi method. Layer I contains a dense plexus of horizontal fibers, the terminal dendritic bouquets of pyramidal cells of layer II and of underlying layers, and varieties of intrinsic neurons. Four main types of cells were found in layer I. Small horizontal cells represent most probably persisting foetal horizontal cells described for other mammals. Large horizontal cells, tufted cells, and spinous horizontal cells were also found in this layer. Layer II contains primitive pyramidal cells representing the most outstanding feature of the neocortex of the hedgehog. Most pyramidal cells in layer II have two, three or more apical dendrites, richly covered by spines predominating over the basal dendrites. These cells resemble pyramidal cells found in the piriform cortex, hippocampus and other olfactory areas. It is suggested that the presence of these neurons reflects the retention of a primitive character in neocortical evolution. Cells with intrinsic axons were found among pyramidal cells in layer II. These have smooth dendrites penetrating layer I and local axons forming extremely complex terminal arborizations around the bodies and proximal dendritic portions of pyramidal cells. They most probably effect numerous axo-somatic contacts resembling basket cells. The similarity of some axonal terminals with the chandelier type of axonal arborization is discussed. Other varieties of cells located in deep cortical layers and having ascending axons for layers I and II were also studied. It is concluded that the two first neocortical layers represent a level of important integration in this primitive mammal.

Correlation between hedgehog (hh) protein family and brain-derived neurotrophic factor (bdnf) in autism spectrum disorder (asd)

International Nuclear Information System (INIS)

Halepoto, D.M.; Bashir, S.

2015-01-01

To determine the correlation of Sonic Hedgehog (SHH), Indian Hedgehog (IHH), and Brain-Derived Neurotrophic Factor (BDNF) in children with Autism Spectrum Disorder (ASD). Study Design: An observational, comparative study. Place and Duration of Study: Autism Research and Treatment Center, Al-Amodi Autism Research Chair, Department of Physiology, Faculty of Medicine, King Khalid University Hospital, King Saud University, Riyadh, Saudi Arabia, from October 2011 to May 2012. Methodology: Serum levels of SHH, IHH and BDNF were determined in recently diagnosed autistic patients and age matched healthy children (n=25), using the Enzyme-Linked Immunosorbent Assay (ELISA). Childhood Autism Rating Scale (CARS) was used for the assessment of autistic severity. Spearman correlation co-efficient-r was determined. Results: The serum levels of IHH and SHH were significantly higher in autistic subjects than those of control subjects. There was significant correlation between age and IHH (r = 0.176, p = 0.03), BDNF and severe IHH (r = 0.1763, p = 0.003), and severe BDNF and severe SHH (r = 0.143, p < 0.001). However, there were no significant relationships among the serum levels of SHH, IHH and BDNF and the CARS score, age or gender. Conclusion: The findings support a correlation between SHH, IHH and BDNF in autistic children, suggesting their pathological role in autism. (author)

Relevance of hair and spines of the European hedgehog (Erinaceus europaeus) as biomonitoring tissues for arsenic and metals in relation to blood

NARCIS (Netherlands)

Vermeulen, F.; Havé, D' H.; Mubiana, V.K.; Brink, van den N.W.; Blust, R.; Bervoets, L.; Coen, De W.

2009-01-01

Hair has been proven to be suitable for non-destructive and non-invasive exposure assessments in human and mammal populations. A previous study with European hedgehog (Erinaceus europaeus) showed that, for some metals, hair and spine metal concentrations were positively correlated to levels in

Disparate effects of oxidation on plasma acyltransferase activities: inhibition of cholesterol esterification but stimulation of transesterification of oxidized phospholipids.

Science.gov (United States)

Subbaiah, P V; Liu, M

1996-05-31

Oxidation of lipoproteins results in the formation of several polar phospholipids with pro-inflammatory and pro-atherogenic properties. To examine the possible role of lecithin/cholesterol acyltransferase (LCAT) in the metabolism of these oxidized phospholipids, we oxidized whole plasma with either Cu(2+) or a free-radical generator, and determined the various activities of LCAT. Oxidation caused a reduction in plasma phosphatidylcholine (PC), an increase in a short-chain polar PC (SCP-PC), and an inhibition of the transfer of long-chain acyl groups to cholesterol (LCAT activity) or to lyso PC (lysolecithin acyltransferase (LAT) I activity). However, the transfer of short-chain acyl groups from SCP-PC to lyso PCLAT II activity) was stimulated several fold, in direct correlation with the degree of oxidation. LAT II activity was not stimulated by oxidation in LCAT-deficient plasma, showing that it is carried out by LCAT. Oxidized normal plasma exhibited low LCAT activity even in the presence of exogenous proteoliposome substrate, indicating that the depletion of substrate PC was not responsible for the loss of activity. Oxidation of isolated LDL or HDL abolished their ability to support LCAT and LAT I activities of exogenous enzyme, but promoted the LAT II activity. Purified LCAT lost its LCAT and LAT I functions, but not its LAT II function, when oxidized in vitro. These results show that while oxidation of plasma causes a loss of LCAT's ability to transfer long-chain acyl groups, its ability to transfer short-chain acyl groups, from SCP-PC is retained, and even stimulated, suggesting that LCAT may have a physiological role in the metabolism of oxidized PC in plasma.

Non-destructive pollution exposure assessment in the European hedgehog (Erinaceus europaeus): IV hair versus soil analysis in exposure and risk assessment of organochlorine compounds

NARCIS (Netherlands)

Havé, D' H.; Scheirs, J.; Covaci, A.; Brink, van den N.W.; Verhagen, R.; Coen, De W.

2007-01-01

Few ecotoxicological studies on mammals use non-destructive methodologies, despite the growing ethical concern over the use of destructive sampling methods. In the present study we assessed exposure of hedgehogs (Erinaceus europaeus) to polychlorinated biphenyls (PCBs),

Lysophosphatidylcholine acyltransferase1 overexpression promotes oral squamous cell carcinoma progression via enhanced biosynthesis of platelet-activating factor.

Science.gov (United States)

Shida-Sakazume, Tomomi; Endo-Sakamoto, Yosuke; Unozawa, Motoharu; Fukumoto, Chonji; Shimada, Ken; Kasamatsu, Atsushi; Ogawara, Katsunori; Yokoe, Hidetaka; Shiiba, Masashi; Tanzawa, Hideki; Uzawa, Katsuhiro

2015-01-01

The relevance of lysophosphatidylcholine acyltransferase1 (LPCAT1), a cytosolic enzyme in the remodeling pathway of phosphatidylcholine metabolism, in oral squamous cell carcinoma (OSCC) is unknown. We investigated LPCAT1 expression and its functional mechanism in OSCCs. We analyzed LPCAT1 mRNA and protein expression levels in OSCC-derived cell lines. Immunohistochemistry was performed to identify correlations between LPCAT1 expression levels and primary OSCCs clinicopathological status. We established LPCAT1 knockdown models of the OSCC-derived cell lines (SAS, Ca9-22) for functional analysis and examined the association between LPCAT1 expression and the platelet-activating factor (PAF) concentration and PAF-receptor (PAFR) expression. LPCAT1 mRNA and protein were up-regulated significantly (poral keratinocytes. Immunohistochemistry showed significantly (poral cancer.

Atherogenic Impact of Lecithin-Cholesterol Acyltransferase and Its Relation to Cholesterol Esterification Rate in HDL (FERHDL) and AIP [log(TG/HDL-C)] Biomarkers: The Butterfly Effect?

Czech Academy of Sciences Publication Activity Database

Dobiášová, Milada

2017-01-01

Roč. 66, č. 2 (2017), s. 193-203 ISSN 0862-8408 Institutional support: RVO:67985823 Keywords : lecithin-cholesterol acyltransferase (LCAT) * atherosclerosis * FERHDL (fractional esterification rate in HDL) * AIP (atherogenic index of plasma, log(TG/HDL-C) * biomarkers of cardiometabolic risk * lipoprotein particle size Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery OBOR OECD: Endocrinology and metabolism (including diabetes, hormones) Impact factor: 1.461, year: 2016

Cloning and expression of a novel lysophospholipase which structurally resembles lecithin cholesterol acyltransferase.

Science.gov (United States)

Taniyama, Y; Shibata, S; Kita, S; Horikoshi, K; Fuse, H; Shirafuji, H; Sumino, Y; Fujino, M

1999-04-02

Lecithin cholesterol acyltransferase (LCAT) is the key enzyme in the esterification of plasma cholesterol and in the reverse cholesterol transport on high-density lipoprotein (HDL). We have found a novel LCAT-related gene among differentially expressed cDNA fragments between two types of foam cells derived from THP-1 cells, which are different in cholesterol efflux ability, using a subtractive PCR technique. The deduced 412-amino-acid sequence has 49% amino acid sequence similarity with human LCAT. In contrast to the liver-specific expression of LCAT, mRNA expression of the gene was observed mainly in peripheral tissues including kidney, placenta, pancreas, testis, spleen, heart, and skeletal muscle. The protein exists in human plasma and is probably associated with HDL. Moreover, we discovered that the recombinant protein hydrolyzed lysophosphatidylcholine (lysoPC), a proatherogenic lipid, to glycerophosphorylcholine and a free fatty acid. We have therefore named this novel enzyme LCAT-like lysophospholipase (LLPL), through which a new catabolic pathway for lysoPC on lipoproteins could be elucidated. Copyright 1999 Academic Press.

Inhibition of ghrelin o-acyltransferase attenuated lipotoxicity by inducing autophagy via AMPK–mTOR pathway

Directory of Open Access Journals (Sweden)

Zhang S

2018-04-01

Full Text Available Shaoren Zhang, Yuqing Mao, Xiaoming Fan Department of Gastroenterology and Hepatology, Jinshan Hospital of Fudan University, Shanghai, China Background: Nonalcoholic fatty liver disease (NAFLD has been considered the most commonly occurring chronic hepatopathy in the world. Ghrelin o-acyltransferase (GOAT is an acylation enzyme which has an acylated position 3 serine on ghrelin. Recent investigation revealed that activated autophagy could attenuate liver steatosis. The aim of this study was to explore therapeutic roles that inhibit GOAT exerted in NAFLD, and its potential association with autophagy.Materials and methods: Human LO2 cells were pretreated with siRNA-GOAT to induce liver steatosis using free fatty acids (FFAs. A chronic NAFLD model was established by feeding male mice C57bl/6 with high-fat diet (HFD for 56 days with GO-CoA-Tat administrated subcutaneously. Lipid droplets were identified by Oil Red O stains. Body weight (BW of mice was measured every week. Autophagy, tumor necrosis factor-α (TNF-α, interleukin-6 (IL-6, serum biochemical indicators (glucose [Glu], total cholesterol [TC], triglyceride [TG], aspartate aminotransferase [AST], alanine aminotransferase [ALT] and signaling pathway proteins of phosphorylated AMPK–mTOR were measured.Results: The TG contents of the FFA and HFD groups were decreased by the inhibition of GOAT. Among mice treated with GO-CoA-Tat and siRNA-GOAT, IL-6 and TNF-α concentrations were remarkably decreased. Indicators of liver injury such as ALT and AST were also remarkably decreased among mice treated with GO-CoA-Tat. Likewise, GO-CoA-Tat significantly reduced the BW of mice and serum TG, TC and Glu. Autophagy was induced along with reduced lipids in the cells of the FFA and HFD groups. The inhibition of GOAT upregulated autophagy via AMPK–mTOR restoration.Conclusion: These results indicate that the inhibition of GOAT attenuates lipotoxicity by autophagy stimulation via AMPK–mTOR restoration

Thyroid Hormone Regulates the Expression of the Sonic Hedgehog Signaling Pathway in the Embryonic and Adult Mammalian Brain

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Desouza, Lynette A.; Sathanoori, Malini; Kapoor, Richa; Rajadhyaksha, Neha; Gonzalez, Luis E.; Kottmann, Andreas H.; Tole, Shubha; Vaidya, Vidita A.

2011-01-01

Thyroid hormone is important for development and plasticity in the immature and adult mammalian brain. Several thyroid hormone-responsive genes are regulated during specific developmental time windows, with relatively few influenced across the lifespan. We provide novel evidence that thyroid hormone regulates expression of the key developmental morphogen sonic hedgehog (Shh), and its coreceptors patched (Ptc) and smoothened (Smo), in the early embryonic and adult forebrain. Maternal hypo- and...

Resveratrol Enhances Neurite Outgrowth and Synaptogenesis Via Sonic Hedgehog Signaling Following Oxygen-Glucose Deprivation/Reoxygenation Injury

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Fanren Tang

2017-09-01

Full Text Available Background/Aims: Neurite outgrowth and synaptogenesis are critical steps for functional recovery after stroke. Resveratrol promotes neurite outgrowth and synaptogenesis, but the underlying mechanism is not well understood, although the Sonic hedgehog (Shh signaling pathway may be involved. Given that resveratrol activates sirtuin (Sirt1, the present study examined whether this is mediated by Shh signaling. Methods: Primary cortical neuron cultures were pretreated with drugs before oxygen-glucose deprivation/reoxygenation (OGD/R. Cell viability and apoptosis were evaluated with Cell Counting Kit 8 and by terminal deoxynucleotidyl transferase dUTP nick end labeling, respectively. Neurite outgrowth and synaptogenesis were assessed by immunocytochemistry and western blotting, which was also used to examine the expression of Sirt1 and Shh signaling proteins. Results: Resveratrol and the Smoothened (Smo agonist purmophamine, which activates Shh signaling, increased viability, reduced apoptosis, and stimulated neurite outgrowth after OGD/R injury. Moreover, the expression of growth-associated protein(GAP-43, synaptophysin, Shh, Patched (Ptc-1, Smo, glioma-associated oncogene homolog (Gli-1, and Sirt1 were upregulated under these conditions. These effects were reversed by treatment with the Smo inhibitor cyclopamine, whereas the Sirt1 inhibitor sirtinol reduced the levels of Shh, Ptc-1, Smo, and Gli-1. Conclusions: Resveratrol reduces neuronal injury following OGD/R injury and enhances neurite outgrowth and synaptogenesis by activating Shh signaling, which in turn induces Sirt1.

A mechanism for vertebrate Hedgehog signaling: recruitment to cilia and dissociation of SuFu–Gli protein complexes

OpenAIRE

Tukachinsky, Hanna; Lopez, Lyle V.; Salic, Adrian

2010-01-01

In vertebrates, Hedgehog (Hh) signaling initiated in primary cilia activates the membrane protein Smoothened (Smo) and leads to activation of Gli proteins, the transcriptional effectors of the pathway. In the absence of signaling, Gli proteins are inhibited by the cytoplasmic protein Suppressor of Fused (SuFu). It is unclear how Hh activates Gli and whether it directly regulates SuFu. We find that Hh stimulation quickly recruits endogenous SuFu–Gli complexes to cilia, suggesting a model in wh...

Identification of a pair of phospholipid:diacylglycerol acyltransferases from developing flax (Linum usitatissimum L.) seed catalyzing the selective production of trilinolenin.

Science.gov (United States)

Pan, Xue; Siloto, Rodrigo M P; Wickramarathna, Aruna D; Mietkiewska, Elzbieta; Weselake, Randall J

2013-08-16

The oil from flax (Linum usitatissimum L.) has high amounts of α-linolenic acid (ALA; 18:3(cis)(Δ9,12,15)) and is one of the richest sources of omega-3 polyunsaturated fatty acids (ω-3-PUFAs). To produce ∼57% ALA in triacylglycerol (TAG), it is likely that flax contains enzymes that can efficiently transfer ALA to TAG. To test this hypothesis, we conducted a systematic characterization of TAG-synthesizing enzymes from flax. We identified several genes encoding acyl-CoA:diacylglycerol acyltransferases (DGATs) and phospholipid:diacylglycerol acyltransferases (PDATs) from the flax genome database. Due to recent genome duplication, duplicated gene pairs have been identified for all genes except DGAT2-2. Analysis of gene expression indicated that two DGAT1, two DGAT2, and four PDAT genes were preferentially expressed in flax embryos. Yeast functional analysis showed that DGAT1, DGAT2, and two PDAT enzymes restored TAG synthesis when produced recombinantly in yeast H1246 strain. The activity of particular PDAT enzymes (LuPDAT1 and LuPDAT2) was stimulated by the presence of ALA. Further seed-specific expression of flax genes in Arabidopsis thaliana indicated that DGAT1, PDAT1, and PDAT2 had significant effects on seed oil phenotype. Overall, this study indicated the existence of unique PDAT enzymes from flax that are able to preferentially catalyze the synthesis of TAG containing ALA acyl moieties. The identified LuPDATs may have practical applications for increasing the accumulation of ALA and other polyunsaturated fatty acids in oilseeds for food and industrial applications.

Identification of a Pair of Phospholipid:Diacylglycerol Acyltransferases from Developing Flax (Linum usitatissimum L.) Seed Catalyzing the Selective Production of Trilinolenin*

Science.gov (United States)

Pan, Xue; Siloto, Rodrigo M. P.; Wickramarathna, Aruna D.; Mietkiewska, Elzbieta; Weselake, Randall J.

2013-01-01

The oil from flax (Linum usitatissimum L.) has high amounts of α-linolenic acid (ALA; 18:3cisΔ9,12,15) and is one of the richest sources of omega-3 polyunsaturated fatty acids (ω-3-PUFAs). To produce ∼57% ALA in triacylglycerol (TAG), it is likely that flax contains enzymes that can efficiently transfer ALA to TAG. To test this hypothesis, we conducted a systematic characterization of TAG-synthesizing enzymes from flax. We identified several genes encoding acyl-CoA:diacylglycerol acyltransferases (DGATs) and phospholipid:diacylglycerol acyltransferases (PDATs) from the flax genome database. Due to recent genome duplication, duplicated gene pairs have been identified for all genes except DGAT2-2. Analysis of gene expression indicated that two DGAT1, two DGAT2, and four PDAT genes were preferentially expressed in flax embryos. Yeast functional analysis showed that DGAT1, DGAT2, and two PDAT enzymes restored TAG synthesis when produced recombinantly in yeast H1246 strain. The activity of particular PDAT enzymes (LuPDAT1 and LuPDAT2) was stimulated by the presence of ALA. Further seed-specific expression of flax genes in Arabidopsis thaliana indicated that DGAT1, PDAT1, and PDAT2 had significant effects on seed oil phenotype. Overall, this study indicated the existence of unique PDAT enzymes from flax that are able to preferentially catalyze the synthesis of TAG containing ALA acyl moieties. The identified LuPDATs may have practical applications for increasing the accumulation of ALA and other polyunsaturated fatty acids in oilseeds for food and industrial applications. PMID:23824186

Molecular Characterization of the Elaeis guineensis Medium-Chain Fatty Acid Diacylglycerol Acyltransferase DGAT1-1 by Heterologous Expression in Yarrowia lipolytica.

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Laure Aymé

Full Text Available Diacylglycerol acyltransferases (DGAT are involved in the acylation of sn-1,2-diacylglycerol. Palm kernel oil, extracted from Elaeis guineensis (oil palm seeds, has a high content of medium-chain fatty acids mainly lauric acid (C12:0. A putative E. guineensis diacylglycerol acyltransferase gene (EgDGAT1-1 is expressed at the onset of lauric acid accumulation in the seed endosperm suggesting that it is a determinant of medium-chain triacylglycerol storage. To test this hypothesis, we thoroughly characterized EgDGAT1-1 activity through functional complementation of a Yarrowia lipolytica mutant strain devoid of neutral lipids. EgDGAT1-1 expression is sufficient to restore triacylglycerol accumulation in neosynthesized lipid droplets. A comparative functional study with Arabidopsis thaliana DGAT1 highlighted contrasting substrate specificities when the recombinant yeast was cultured in lauric acid supplemented medium. The EgDGAT1-1 expressing strain preferentially accumulated medium-chain triacylglycerols whereas AtDGAT1 expression induced long-chain triacylglycerol storage in Y. lipolytica. EgDGAT1-1 localized to the endoplasmic reticulum where TAG biosynthesis takes place. Reestablishing neutral lipid accumulation in the Y. lipolytica mutant strain did not induce major reorganization of the yeast microsomal proteome. Overall, our findings demonstrate that EgDGAT1-1 is an endoplasmic reticulum DGAT with preference for medium-chain fatty acid substrates, in line with its physiological role in palm kernel. The characterized EgDGAT1-1 could be used to promote medium-chain triacylglycerol accumulation in microbial-produced oil for industrial chemicals and cosmetics.

Association of expression of the hedgehog signal with Merkel cell polyomavirus infection and prognosis of Merkel cell carcinoma.

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Kuromi, Teruyuki; Matsushita, Michiko; Iwasaki, Takeshi; Nonaka, Daisuke; Kuwamoto, Satoshi; Nagata, Keiko; Kato, Masako; Akizuki, Gen; Kitamura, Yukisato; Hayashi, Kazuhiko

2017-11-01

Merkel cell carcinoma (MCC) is an aggressive neuroendocrine skin cancer that mostly occurs in the elderly. Merkel cell polyomavirus (MCPyV) is detected in approximately 80% of MCCs and is associated with carcinogenesis. Hedgehog signaling pathway plays a role in human embryogenesis and organogenesis. In addition, reactivation of this pathway later in life can cause tumors. Twenty-nineMCPyV-positive and 21 MCPyV-negative MCCs were immunohistochemically stained with primary antibodies for hedgehog signaling (SHH, IHH, PTCH1, SMO, GLI1, GLI2, and GLI3) and evaluated using H-score. Polymerase chain reaction and sequence analysis for SHH and GLI1 exons were also performed. Expression of SHH was higher in MCPyV-positive MCCs than in MCPyV-negative MCCs (PA. Only 2 mutations with amino acid changes were detected in MCPyV-negative MCCs only: 1 missense mutation in GLI1 exon 4 and 1 nonsense mutation in SHH-3B. Expression of SHH and GLI1 may be useful prognostic markers of MCC because increased expression was associated with better prognosis. The high rate of c.576G>A silent mutation in GLI1 exon 5 was a feature of MCC. Copyright © 2017 Elsevier Inc. All rights reserved.

Sonic hedgehog signaling in spinal cord contributes to morphine-induced hyperalgesia and tolerance through upregulating brain-derived neurotrophic factor expression

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Liu S

2018-04-01

signaling. In naïve mice, exogenous activation of Shh signaling caused a rapid increase of BDNF expression, as well as thermal hyperalgesia. Inhibiting BDNF significantly suppressed smoothened agonist-induced hyperalgesia. Conclusion: These findings suggest that Shh signaling may be a critical mediator for MIH and tolerance by regulating BDNF expression. Inhibiting Shh signaling, especially during the early phase, may effectively delay or suppress MIH and tolerance. Keywords: sonic hedgehog, tolerance, hyperalgesia, brain-derived neurotrophic factor, spinal cord

The Potential Role of Hedgehog Signaling in the Luminal/Basal Phenotype of Breast Epithelia and in Breast Cancer Invasion and Metastasis

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Flemban, Arwa [Department of Biological, Biomedical and Analytical Sciences, Faculty of Health and Applied Sciences, University of West of England, Bristol BS16 1QY (United Kingdom); Department of Pathology, Faculty of Medicine, Umm Al-Qura University, Makkah 24382 (Saudi Arabia); Qualtrough, David, E-mail: david.qualtrough@uwe.ac.uk [Department of Biological, Biomedical and Analytical Sciences, Faculty of Health and Applied Sciences, University of West of England, Bristol BS16 1QY (United Kingdom)

2015-09-16

The epithelium of the lactiferous ducts in the breast is comprised of luminal epithelial cells and underlying basal myoepithelial cells. The regulation of cell fate and transit of cells between these two cell types remains poorly understood. This relationship becomes of greater importance when studying the subtypes of epithelial breast carcinoma, which are categorized according to their expression of luminal or basal markers. The epithelial mesenchymal transition (EMT) is a pivotal event in tumor invasion. It is important to understand mechanisms that regulate this process, which bears relation to the normal dynamic of epithelial/basal phenotype regulation in the mammary gland. Understanding this process could provide answers for the regulation of EMT in breast cancer, and thereby identify potential targets for therapy. Evidence points towards a role for hedgehog signaling in breast tissue homeostasis and also in mammary neoplasia. This review examines our current understanding of role of the hedgehog-signaling (Hh) pathway in breast epithelial cells both during breast development and homeostasis and to assess the potential misappropriation of Hh signals in breast neoplasia, cancer stem cells and tumor metastasis via EMT.

The Potential Role of Hedgehog Signaling in the Luminal/Basal Phenotype of Breast Epithelia and in Breast Cancer Invasion and Metastasis

International Nuclear Information System (INIS)

Flemban, Arwa; Qualtrough, David

2015-01-01

The epithelium of the lactiferous ducts in the breast is comprised of luminal epithelial cells and underlying basal myoepithelial cells. The regulation of cell fate and transit of cells between these two cell types remains poorly understood. This relationship becomes of greater importance when studying the subtypes of epithelial breast carcinoma, which are categorized according to their expression of luminal or basal markers. The epithelial mesenchymal transition (EMT) is a pivotal event in tumor invasion. It is important to understand mechanisms that regulate this process, which bears relation to the normal dynamic of epithelial/basal phenotype regulation in the mammary gland. Understanding this process could provide answers for the regulation of EMT in breast cancer, and thereby identify potential targets for therapy. Evidence points towards a role for hedgehog signaling in breast tissue homeostasis and also in mammary neoplasia. This review examines our current understanding of role of the hedgehog-signaling (Hh) pathway in breast epithelial cells both during breast development and homeostasis and to assess the potential misappropriation of Hh signals in breast neoplasia, cancer stem cells and tumor metastasis via EMT

Endogenous Sonic Hedgehog limits inflammation and angiogenesis in the ischaemic skeletal muscle of mice.

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Caradu, Caroline; Guy, Alexandre; James, Chloé; Reynaud, Annabel; Gadeau, Alain-Pierre; Renault, Marie-Ange

2018-04-01

Hedgehog (Hh) signalling has been shown to be re-activated in ischaemic tissues and participate in ischaemia-induced angiogenesis. Sonic Hedgehog (Shh) is upregulated by more than 80-fold in the ischaemic skeletal muscle, however its specific role in ischaemia-induced angiogenesis has not yet been fully investigated. The purpose of the present study was to investigate the role of endogenous Shh in ischaemia-induced angiogenesis. To this aim, we used inducible Shh knock-out (KO) mice and unexpectedly found that capillary density was significantly increased in re-generating muscle of Shh deficient mice 5 days after hind limb ischaemia was induced, demonstrating that endogenous Shh does not promote angiogenesis but more likely limits it. Myosin and MyoD expression were equivalent in Shh deficient mice and control mice, indicating that endogenous Shh is not required for ischaemia-induced myogenesis. Additionally, we observed a significant increase in macrophage infiltration in the ischaemic muscle of Shh deficient mice. Our data indicate that this was due to an increase in chemokine expression by myoblasts in the setting of impaired Hh signalling, using tissue specific Smoothened conditional KO mice. The increased macrophage infiltration in mice deficient for Hh signalling in myocytes was associated with increased VEGFA expression and a transiently increased angiogenesis, demonstrating that Shh limits inflammation and angiogenesis indirectly by signalling to myocytes. Although ectopic administration of Shh has previously been shown to promote ischaemia-induced angiogenesis, the present study reveals that endogenous Shh does not promote ischaemia-induced angiogenesis. On the contrary, the absence of Shh leads to aberrant ischaemic tissue inflammation and a transiently increased angiogenesis.

PM2.5 promotes human bronchial smooth muscle cell migration via the sonic hedgehog signaling pathway.

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Ye, Xiuqin; Hong, Wei; Hao, Binwei; Peng, Gongyong; Huang, Lingmei; Zhao, Zhuxiang; Zhou, Yumin; Zheng, Mengning; Li, Chenglong; Liang, Chunxiao; Yi, Erkang; Pu, Jinding; Li, Bing; Ran, Pixin

2018-03-02

The contribution of airway remodeling in chronic obstructive pulmonary disease (COPD) has been well documented, with airway smooth muscle cell proliferation and migration playing a role in the remodeling process. Here, we aimed to verify the effects of fine particulate matter (PM2.5) on human bronchial smooth muscle cell (HBSMC) migration and to explore the underlying signaling pathways. HBSMC apoptosis, proliferation and migration were measured using flow cytometry, cell counting and transwell migration assays, respectively. The role of the hedgehog pathway in cell migration was assessed by western blotting to measure the expression of Sonic hedgehog (Shh), Gli1 and Snail. Furthermore, siRNA was used to knock down Gli1 or Snail expression. PM2.5 induced HBSMC apoptosis in a dose-dependent manner, although certain concentrations of PM2.5 did not induce HBSMC proliferation or apoptosis. Interestingly, cell migration was stimulated by PM2.5 doses far below those that induced apoptosis. Additional experiments revealed that these PM2.5 doses enhanced the expression of Shh, Gli1 and Snail in HBSMCs. Furthermore, PM2.5-induced cell migration and protein expression were enhanced by recombinant Shh and attenuated by cyclopamine. Similar results were obtained by knocking down Gli1 or Snail. These findings suggest that PM2.5, which may exert its effects through the Shh signaling pathway, is necessary for the migration of HBSMCs. These data define a novel role for PM2.5 in airway remodeling in COPD.

Epithelial trafficking of Sonic hedgehog by megalin.

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Morales, Carlos R; Zeng, Jibin; El Alfy, Mohamed; Barth, Jeremy L; Chintalapudi, Mastan Rao; McCarthy, Robert A; Incardona, John P; Argraves, W Scott

2006-10-01

We present here evidence of in vivo epithelial endocytosis and trafficking of non-lipid-modified Sonic hedgehog (ShhN) when infused into rat efferent ducts via microinjection. Initially, exogenous ShhN is detected in endocytic vesicles and early endosomes located near the apical plasma membrane of non-ciliated cells. Within 30-60 min following infusion, ShhN can be detected in lysosomes and at basolateral regions of non-ciliated cells. Basolaterally, ShhN was observed along the extracellular surfaces of interdigitated plasma membranes of adjacent cells and in the extracellular compartment underlying the efferent duct epithelium. Uptake and subcellular trafficking of infused ShhN by non-ciliated cells could be blocked by either anti-megalin IgG or the megalin antagonist, RAP. Ciliated cells, which do not express megalin, displayed little if any apical internalization of ShhN even though they were found to express Patched-1. However, ShhN was found in coated pits of lateral plasma membranes of ciliated cells as well as in underlying endocytic vesicles. We conclude that megalin-mediated endocytosis of ShhN can occur in megalin-expressing epithelia in vivo, and that the internalized ShhN can be targeted to the lysosome or transcytosed in the plane of the epithelium or across the epithelium. These findings highlight the multiple mechanisms by which megalin may influence Shh morphogen gradients in vivo.

Hedgehog signaling is required for formation of the notochord sheath and patterning of nuclei pulposi within the intervertebral discs

OpenAIRE

Choi, Kyung-Suk; Harfe, Brian D.

2011-01-01

The vertebrae notochord is a transient rod-like structure that produces secreted factors that are responsible for patterning surrounding tissues. During later mouse embryogenesis, the notochord gives rise to the middle part of the intervertebral disc, called the nucleus pulposus. Currently, very little is known about the molecular mechanisms responsible for forming the intervertebral discs. Here we demonstrate that hedgehog signaling is required for formation of the intervertebral discs. Remo...

GLI1, a crucial mediator of sonic hedgehog signaling in prostate cancer, functions as a negative modulator for androgen receptor

International Nuclear Information System (INIS)

Chen, Guangchun; Goto, Yutaka; Sakamoto, Ryuichi; Tanaka, Kimitaka; Matsubara, Eri; Nakamura, Masafumi; Zheng, Hong; Lu, Jian; Takayanagi, Ryoichi; Nomura, Masatoshi

2011-01-01

Research highlights: → GLI1, which play a central role in sonic hedgehog signaling in prostate cancer, can act as a co-repressor to substantially block androgen receptor-mediated transactivation. → GLI1 directly interacts with AR. → SHH-GLI pathway might be one of determinants governing the transition of prostate cancer from an androgen-dependent to an androgen-independent state. -- Abstract: Sonic hedgehog (SHH) signaling, acting in a combinatorial manner with androgen signaling, is essential for prostate patterning and development. Recently, elevated activation of SHH signaling has been shown to play important roles in proliferation, progression and metastasis of prostate cancer. In this report, we demonstrate for the first time, that GLI1, which has been shown to play a central role in SHH signaling in prostate cancer, can act as a co-repressor to substantially block androgen receptor (AR)-mediated transactivation, at least in part, by directly interacting with AR. Our observations suggest that the SHH-GLI pathway might be one of determinants governing the transition of prostate cancer from an androgen-dependent to an androgen-independent state by compensating, or even superseding androgen signaling.

Overactivation of Hedgehog Signaling Alters Development of the Ovarian Vasculature in Mice1

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Ren, Yi; Cowan, Robert G.; Migone, Fernando F.; Quirk, Susan M.

2012-01-01

ABSTRACT The hedgehog (HH) signaling pathway is critical for ovarian function in Drosophila, but its role in the mammalian ovary has not been defined. Previously, expression of a dominant active allele of the HH signal transducer protein smoothened (SMO) in Amhr2cre/+SmoM2 mice caused anovulation in association with a lack of smooth muscle in the theca of developing follicles. The current study examined events during the first 2 wk of life in Amhr2cre/+SmoM2 mice to gain insight into the cause of anovulation. Expression of transcriptional targets of HH signaling, Gli1, Ptch1, and Hhip, which are used as measures of pathway activity, were elevated during the first several days of life in Amhr2cre/+SmoM2 mice compared to controls but were similar to controls in older mice. Microarray analysis showed that genes with increased expression in 2-day-old mutants compared to controls were enriched for the processes of vascular and tube development and steroidogenesis. The density of platelet endothelial cell adhesion molecule (PECAM)-labeled endothelial tubes was increased in the cortex of newborn ovaries of mutant mice. Costaining of preovulatory follicles for PECAM and smooth muscle actin showed that muscle-type vascular support cells are deficient in theca of mutant mice. Expression of genes for steroidogenic enzymes that are normally expressed in the fetal adrenal gland were elevated in newborn ovaries of mutant mice. In summary, overactivation of HH signaling during early life alters gene expression and vascular development and this is associated with the lifelong development of anovulatory follicles in which the thecal vasculature fails to mature appropriately. PMID:22402963

Analysis of triglyceride synthesis unveils a green algal soluble diacylglycerol acyltransferase and provides clues to potential enzymatic components of the chloroplast pathway.

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Bagnato, Carolina; Prados, María B; Franchini, Gisela R; Scaglia, Natalia; Miranda, Silvia E; Beligni, María V

2017-03-09

Microalgal triglyceride (TAG) synthesis has attracted considerable attention. Particular emphasis has been put towards characterizing the algal homologs of the canonical rate-limiting enzymes, diacylglycerol acyltransferase (DGAT) and phospholipid:diacylglycerol acyltransferase (PDAT). Less work has been done to analyze homologs from a phylogenetic perspective. In this work, we used HMMER iterative profiling and phylogenetic and functional analyses to determine the number and sequence characteristics of algal DGAT and PDAT, as well as related sequences that constitute their corresponding superfamilies. We included most algae with available genomes, as well as representative eukaryotic and prokaryotic species. Amongst our main findings, we identified a novel clade of DGAT1-like proteins exclusive to red algae and glaucophyta and a previously uncharacterized subclade of DGAT2 proteins with an unusual number of transmembrane segments. Our analysis also revealed the existence of a novel DGAT exclusive to green algae with moderate similarity to plant soluble DGAT3. The DGAT3 clade shares a most recent ancestor with a group of uncharacterized proteins from cyanobacteria. Subcellular targeting prediction suggests that most green algal DGAT3 proteins are imported to the chloroplast, evidencing that the green algal chloroplast might have a soluble pathway for the de novo synthesis of TAGs. Heterologous expression of C. reinhardtii DGAT3 produces an increase in the accumulation of TAG, as evidenced by thin layer chromatography. Our analysis contributes to advance in the knowledge of complex superfamilies involved in lipid metabolism and provides clues to possible enzymatic players of chloroplast TAG synthesis.

The Role of Diacylglycerol Acyltransferase (DGAT) 1 and 2 in Cardiac Metabolism and Function.

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Roe, Nathan D; Handzlik, Michal K; Li, Tao; Tian, Rong

2018-03-21

It is increasingly recognized that synthesis and turnover of cardiac triglyceride (TG) play a pivotal role in the regulation of lipid metabolism and function of the heart. The last step in TG synthesis is catalyzed by diacylglycerol:acyltransferase (DGAT) which esterifies the diacylglycerol with a fatty acid. Mammalian heart has two DGAT isoforms, DGAT1 and DGAT2, yet their roles in cardiac metabolism and function remain poorly defined. Here, we show that inactivation of DGAT1 or DGAT2 in adult mouse heart results in a moderate suppression of TG synthesis and turnover. Partial inhibition of DGAT activity increases cardiac fatty acid oxidation without affecting PPARα signaling, myocardial energetics or contractile function. Moreover, coinhibition of DGAT1/2 in the heart abrogates TG turnover and protects the heart against high fat diet-induced lipid accumulation with no adverse effects on basal or dobutamine-stimulated cardiac function. Thus, the two DGAT isoforms in the heart have partially redundant function, and pharmacological inhibition of one DGAT isoform is well tolerated in adult hearts.

Test and evaluation report for Westinghouse Hanford Company's Hedgehog Shielded Container, Docket 94-39-7A, Type A container

International Nuclear Information System (INIS)

Kelly, D.L.

1995-01-01

This report documents the US Department of Transportation Specification 7A Type A (DOT-7A) compliance test results of the Westinghouse Hanford Company Hedgehog Shielded Container. The Hedgehog packaging configurations provide primary and secondary containment. The packaging configurations tested consisted of an internal bottle, varying in size. Testing showed that the bottles are not required for the packaging to pass Type A requirements, with the exception of the 1-liter version, in which the polyvinyl chloride (PVC)-coated glass bottle used in testing is considered a part of the containment system. The packaging configurations were evaluated and tested in February 1995. The packaging configurations described in this report are designed to ship Type A quantities of radioactive materials, normal form. Contents may be in solid or liquid form. Liquids may have a specific gravity ≤2. The solid versions would allow the shipment of normal or special form solids. The solid materials would be limited in weight--to include packaging--to the gross weight of the as-tested liquids and bottles. The packaging configurations described in this document may be transported by air, and they meet the applicable International Air Transport Association/International Civil Aviation Organization (IATA/ICAO) Dangerous Goods Regulations in addition to the DOT-7A requirements

Hedgehog Signals Mediate Anti-Cancer Drug Resistance in Three-Dimensional Primary Colorectal Cancer Organoid Culture

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Tatsuya Usui

2018-04-01

Full Text Available Colorectal cancer is one of the most common causes of cancer death worldwide. In patients with metastatic colorectal cancer, combination treatment with several anti-cancer drugs is employed and improves overall survival in some patients. Nevertheless, most patients with metastatic disease are not cured owing to the drug resistance. Cancer stem cells are known to regulate resistance to chemotherapy. In the previous study, we established a novel three-dimensional organoid culture model from tumor colorectal tissues of human patients using an air–liquid interface (ALI method, which contained numerous cancer stem cells and showed resistance to 5-fluorouracil (5-FU and Irinotecan. Here, we investigate which inhibitor for stem cell-related signal improves the sensitivity for anti-cancer drug treatment in tumor ALI organoids. Treatment with Hedgehog signal inhibitors (AY9944, GANT61 decreases the cell viability of organoids compared with Notch (YO-01027, DAPT and Wnt (WAV939, Wnt-C59 signal inhibitors. Combination treatment of AY9944 or GANT61 with 5-FU, Irinotecan or Oxaliplatin decreases the cell viability of tumor organoids compared with each anti-cancer drug alone treatment. Treatment with AY9944 or GANT61 inhibits expression of stem cell markers c-Myc, CD44 and Nanog, likely through the decrease of their transcription factor, GLI-1 expression. Combination treatment of AY9944 or GANT61 with 5-FU or Irinotecan also prevents colony formation of colorectal cancer cell lines HCT116 and SW480. These findings suggest that Hedgehog signals mediate anti-cancer drug resistance in colorectal tumor patient-derived ALI organoids and that the inhibitors are useful as a combinational therapeutic strategy against colorectal cancer.

Complete mitochondrial genome sequence of the hedgehog seahorse Hippocampus spinosissimus Weber, 1933 (Gasterosteiformes:Syngnathidae).

Science.gov (United States)

Liu, Shuaishuai; Zhang, Yanhong; Wang, Changming; Lin, Qiang

2016-07-01

The complete mitochondrial genome sequence of the hedgehog seahorse Hippocampus spinosissimus was first determined in this article. The total length of H. spinosissimus mitogenome is 16 527 bp and consists of 13 protein-coding genes, 2 rRNA genes, 22 tRNA genes and 1 control region. The gene order and composition of H. spinosissimus were similar to those of most other vertebrates. The overall base composition of H. spinosissimus is 32.1% A, 30.3% T, 14.9% G and 22.7% C, with a slight A + T-rich feature (62.4%). Phylogenetic analyses based on complete mitochondrial genome sequence showed that H. spinosissimus has a close genetic relationship to H. ingens and H. kuda.

Pitchfork and Gprasp2 Target Smoothened to the Primary Cilium for Hedgehog Pathway Activation.

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Bomi Jung

Full Text Available The seven-transmembrane receptor Smoothened (Smo activates all Hedgehog (Hh signaling by translocation into the primary cilia (PC, but how this is regulated is not well understood. Here we show that Pitchfork (Pifo and the G protein-coupled receptor associated sorting protein 2 (Gprasp2 are essential components of an Hh induced ciliary targeting complex able to regulate Smo translocation to the PC. Depletion of Pifo or Gprasp2 leads to failure of Smo translocation to the PC and lack of Hh target gene activation. Together, our results identify a novel protein complex that is regulated by Hh signaling and required for Smo ciliary trafficking and Hh pathway activation.

Insulin-induced activation of glycerol-3-phosphate acyltransferase by a chiro-inositol-containing insulin mediator is defective in adipocytes of insulin-resistant, type II diabetic, Goto-Kakizaki rats.

OpenAIRE

Farese, R V; Standaert, M L; Yamada, K; Huang, L C; Zhang, C; Cooper, D R; Wang, Z; Yang, Y; Suzuki, S; Toyota, T

1994-01-01

Type II diabetic Goto-Kakizaki (GK) rats were insulin-resistant in euglycemic-hyperinsulinemic clamp studies. We therefore examined insulin signaling systems in control Wistar and diabetic GK rats. Glycerol-3-phosphate acyltransferase (G3PAT), which is activated by headgroup mediators released from glycosyl-phosphatidylinositol (GPI), was activated by insulin in intact and cell-free adipocyte preparations of control, but not diabetic, rats. A specific chiro-inositol-containing inositol phosph...

Novel Sonic Hedgehog Mutation in a Couple with Variable Expression of Holoprosencephaly

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M. Aguinaga

2011-01-01

Full Text Available Holoprosencephaly (HPE is the most common developmental defect of the forebrain and midface in humans. sporadic and inherited mutations in the human sonic hedgehog (SHH gene cause 37% of familial HPE. A couple was referred to our unit with a family history of two spontaneous first trimester miscarriages and a daughter with HPE who presented early neonatal death. The father had a repaired median cleft lip, absence of central incisors, facial medial hypoplasia, and cleft palate. Intelligence and a brain CT scan were normal. Direct paternal sequencing analysis showed a novel nonsense mutation (W127X. Facial characteristics are considered as HPE microforms, and the pedigree suggested autosomal dominant inheritance with a variable expression of the phenotype. This study reinforces the importance of an exhaustive evaluation of couples with a history of miscarriages and neonatal deaths with structural defects.

Mesencephalic basolateral domain specification is dependent on Sonic Hedgehog

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Jesus E. Martinez-Lopez

2015-02-01

Full Text Available In the study of central nervous system morphogenesis, the identification of new molecular markers allows us to identify domains along the antero-posterior and dorso-ventral axes. In the past years, the alar and basal plates of the midbrain have been divided into different domains. The precise location of the alar-basal boundary is still under discussion. We have identified Barhl1, Nhlh1 and Six3 as appropriate molecular markers to the adjacent domains of this transition. The description of their expression patterns and the contribution to the different mesencephalic populations corroborated their role in the specification of these domains. We studied the influence of Sonic Hedgehog on these markers and therefore on the specification of these territories. The lack of this morphogen produced severe alterations in the expression pattern of Barhl1 and Nhlh1 with consequent misspecification of the basolateral domain. Six3 expression was apparently unaffected, however its distribution changed leading to altered basal domains. In this study we confirmed the localization of the alar-basal boundary dorsal to the basolateral domain and demonstrated that the development of the basolateral domain highly depends on Shh.

Mesencephalic basolateral domain specification is dependent on Sonic Hedgehog

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Martinez-Lopez, Jesus E.; Moreno-Bravo, Juan A.; Madrigal, M. Pilar; Martinez, Salvador; Puelles, Eduardo

2015-01-01

In the study of central nervous system morphogenesis, the identification of new molecular markers allows us to identify domains along the antero-posterior and dorso-ventral (DV) axes. In the past years, the alar and basal plates of the midbrain have been divided into different domains. The precise location of the alar-basal boundary is still under discussion. We have identified Barhl1, Nhlh1 and Six3 as appropriate molecular markers to the adjacent domains of this transition. The description of their expression patterns and the contribution to the different mesencephalic populations corroborated their role in the specification of these domains. We studied the influence of Sonic Hedgehog on these markers and therefore on the specification of these territories. The lack of this morphogen produced severe alterations in the expression pattern of Barhl1 and Nhlh1 with consequent misspecification of the basolateral (BL) domain. Six3 expression was apparently unaffected, however its distribution changed leading to altered basal domains. In this study we confirmed the localization of the alar-basal boundary dorsal to the BL domain and demonstrated that the development of the BL domain highly depends on Shh. PMID:25741244

Antagonism between Hedgehog and Wnt signaling pathways regulates tumorigenicity.

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Ding, Mei; Wang, Xin

2017-12-01

The crosstalk of multiple cellular signaling pathways is crucial in animal development and tissue homeostasis, and its dysregulation may result in tumor formation and metastasis. The Hedgehog (Hh) and Wnt signaling pathways are both considered to be essential regulators of cell proliferation, differentiation and oncogenesis. Recent studies have indicated that the Hh and Wnt signaling pathways are closely associated and involved in regulating embryogenesis and cellular differentiation. Hh signaling acts upstream of the Wnt signaling pathway, and negative regulates Wnt activity via secreted frizzled-related protein 1 (SFRP1), and the Wnt/β-catenin pathway downregulates Hh activity through glioma-associated oncogene homolog 3 transcriptional regulation. This evidence suggests that the imbalance of Hh and Wnt regulation serves a crucial role in cancer-associated processes. The activation of SFRP1, which inhibits Wnt, has been demonstrated to be an important cross-point between the two signaling pathways. The present study reviews the complex interaction between the Hh and Wnt signaling pathways in embryogenesis and tumorigenicity, and the role of SFRP1 as an important mediator associated with the dysregulation of the Hh and Wnt signaling pathways.

A Joint Less Ordinary: Intriguing Roles for Hedgehog Signalling in the Development of the Temporomandibular Synovial Joint

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Malgorzata Kubiak

2016-08-01

Full Text Available This review highlights the essential role of Hedgehog (Hh signalling in the developmental steps of temporomandibular joint (TMJ formation. We review evidence for intra- and potentially inter-tissue Hh signaling as well as Glioma-Associated Oncogene Homolog (GLI dependent and independent functions. Morphogenesis and maturation of the TMJ’s individual components and the general landscape of Hh signalling is also covered. Comparison of the appendicular knee and axial TMJ also reveals interesting differences and similarities in their mechanisms of development, chondrogenesis and reliance on Hh signalling.

A Joint Less Ordinary: Intriguing Roles for Hedgehog Signalling in the Development of the Temporomandibular Synovial Joint

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Kubiak, Malgorzata; Ditzel, Mark

2016-01-01

This review highlights the essential role of Hedgehog (Hh) signalling in the developmental steps of temporomandibular joint (TMJ) formation. We review evidence for intra- and potentially inter-tissue Hh signaling as well as Glioma-Associated Oncogene Homolog (GLI) dependent and independent functions. Morphogenesis and maturation of the TMJ’s individual components and the general landscape of Hh signalling is also covered. Comparison of the appendicular knee and axial TMJ also reveals interesting differences and similarities in their mechanisms of development, chondrogenesis and reliance on Hh signalling. PMID:29615589

Synergism between Hedgehog-GLI and EGFR signaling in Hedgehog-responsive human medulloblastoma cells induces downregulation of canonical Hedgehog-target genes and stabilized expression of GLI1.

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Frank Götschel

Full Text Available Aberrant activation of Hedgehog (HH signaling has been identified as a key etiologic factor in many human malignancies. Signal strength, target gene specificity, and oncogenic activity of HH signaling depend profoundly on interactions with other pathways, such as epidermal growth factor receptor-mediated signaling, which has been shown to cooperate with HH/GLI in basal cell carcinoma and pancreatic cancer. Our experimental data demonstrated that the Daoy human medulloblastoma cell line possesses a fully inducible endogenous HH pathway. Treatment of Daoy cells with Sonic HH or Smoothened agonist induced expression of GLI1 protein and simultaneously prevented the processing of GLI3 to its repressor form. To study interactions between HH- and EGF-induced signaling in greater detail, time-resolved measurements were carried out and analyzed at the transcriptomic and proteomic levels. The Daoy cells responded to the HH/EGF co-treatment by downregulating GLI1, PTCH, and HHIP at the transcript level; this was also observed when Amphiregulin (AREG was used instead of EGF. We identified a novel crosstalk mechanism whereby EGFR signaling silences proteins acting as negative regulators of HH signaling, as AKT- and ERK-signaling independent process. EGFR/HH signaling maintained high GLI1 protein levels which contrasted the GLI1 downregulation on the transcript level. Conversely, a high-level synergism was also observed, due to a strong and significant upregulation of numerous canonical EGF-targets with putative tumor-promoting properties such as MMP7, VEGFA, and IL-8. In conclusion, synergistic effects between EGFR and HH signaling can selectively induce a switch from a canonical HH/GLI profile to a modulated specific target gene profile. This suggests that there are more wide-spread, yet context-dependent interactions, between HH/GLI and growth factor receptor signaling in human malignancies.

Hedgehog regulates Norrie disease protein to drive neural progenitor self-renewal.

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McNeill, Brian; Mazerolle, Chantal; Bassett, Erin A; Mears, Alan J; Ringuette, Randy; Lagali, Pamela; Picketts, David J; Paes, Kim; Rice, Dennis; Wallace, Valerie A

2013-03-01

Norrie disease (ND) is a congenital disorder characterized by retinal hypovascularization and cognitive delay. ND has been linked to mutations in 'Norrie Disease Protein' (Ndp), which encodes the secreted protein Norrin. Norrin functions as a secreted angiogenic factor, although its role in neural development has not been assessed. Here, we show that Ndp expression is initiated in retinal progenitors in response to Hedgehog (Hh) signaling, which induces Gli2 binding to the Ndp promoter. Using a combination of genetic epistasis and acute RNAi-knockdown approaches, we show that Ndp is required downstream of Hh activation to induce retinal progenitor proliferation in the retina. Strikingly, Ndp regulates the rate of cell-cycle re-entry and not cell-cycle kinetics, thereby uncoupling the self-renewal and cell-cycle progression functions of Hh. Taken together, we have uncovered a cell autonomous function for Ndp in retinal progenitor proliferation that is independent of its function in the retinal vasculature, which could explain the neural defects associated with ND.

Brachydactyly type A1 associated with unusual radiological findings and a novel Arg158Cys mutation in the Indian hedgehog (IHH) gene.

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Stattin, Eva-Lena; Lindén, Bjarne; Lönnerholm, Torsten; Schuster, Jens; Dahl, Niklas

2009-01-01

Brachydactyly type A1 (BDA1; MIM 112500) is characterized by shortness or absence of the middle phalanx of the hands and feet. The condition is caused by heterozygous mutations in the Indian hedgehog (IHH) gene or a yet unidentified gene on chromosome 5p13. We investigated six affected members of a large Swedish family segregating autosomal dominant brachymesophalangia. Affected individuals show hypoplasia of the ulnar styloid processes, ulna minus, osteoarthritis, normal length of all distal phalanges and shortening or absence of the middle phalanges. Stationary ossicles or sesamoid bones were observed at the metacarpal heads in all patients. Genetic analysis of the family showed that the IHH-gene was linked to the disease (Z(max) 3.42 at theta 0.00) and sequence analysis of IHH revealed a novel c.472C > T transition in all affected family members. The mutation results in a p.158Arg > Cys substitution located in the highly conserved amino-terminal domain of IHH. This domain is of importance for the interaction between IHH and the Patched receptor. Our combined findings add radiological findings to the BDA1 phenotype and confirm a critical functional domain of IHH.

SDCCAG8 Interacts with RAB Effector Proteins RABEP2 and ERC1 and Is Required for Hedgehog Signaling.

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Rannar Airik

Full Text Available Recessive mutations in the SDCCAG8 gene cause a nephronophthisis-related ciliopathy with Bardet-Biedl syndrome-like features in humans. Our previous characterization of the orthologous Sdccag8gt/gt mouse model recapitulated the retinal-renal disease phenotypes and identified impaired DNA damage response signaling as an underlying disease mechanism in the kidney. However, several other phenotypic and mechanistic features of Sdccag8gt/gt mice remained unexplored. Here we show that Sdccag8gt/gt mice exhibit developmental and structural abnormalities of the skeleton and limbs, suggesting impaired Hedgehog (Hh signaling. Indeed, cell culture studies demonstrate the requirement of SDCCAG8 for ciliogenesis and Hh signaling. Using an affinity proteomics approach, we demonstrate that SDCCAG8 interacts with proteins of the centriolar satellites (OFD1, AZI1, of the endosomal sorting complex (RABEP2, ERC1, and with non-muscle myosin motor proteins (MYH9, MYH10, MYH14 at the centrosome. Furthermore, we show that RABEP2 localization at the centrosome is regulated by SDCCAG8. siRNA mediated RABEP2 knockdown in hTERT-RPE1 cells leads to defective ciliogenesis, indicating a critical role for RABEP2 in this process. Together, this study identifies several centrosome-associated proteins as novel SDCCAG8 interaction partners, and provides new insights into the function of SDCCAG8 at this structure.

Sonic hedgehog signaling in the development of the mouse hypothalamus

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Sandra eBlaess

2015-01-01

Full Text Available The expression pattern of Sonic Hedgehog (Shh in the developing hypothalamus changes over time. Shh is initially expressed in the prechordal mesoderm and later in the hypothalamic neuroepithelium-- first medially, and then in two off-medial domains. This dynamic expression suggests that Shh might regulate several aspects of hypothalamic development. To gain insight into them, lineage tracing, (conditional gene inactivation in mouse, in ovo loss- and gain-of-function approaches in chick and analysis of Shh expression regulation have been employed. We will focus on mouse studies and refer to chick and fish when appropriate to clarify. These studies show that Shh-expressing neuroepithelial cells serve as a signaling center for neighboring precursors, and give rise to most of the basal hypothalamus (tuberal and mammillary regions. Shh signaling is initially essential for hypothalamic induction. Later, Shh signaling from the neuroepithelium controls specification of the lateral hypothalamic area and growth-patterning coordination in the basal hypothalamus. To further elucidate the role of Shh in hypothalamic development, it will be essential to understand how Shh regulates the downstream Gli transcription factors.

Genome-Wide Identification of BAHD Acyltransferases and In vivo Characterization of HQT-like Enzymes Involved in Caffeoylquinic Acid Synthesis in Globe Artichoke

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Moglia, Andrea; Acquadro, Alberto; Eljounaidi, Kaouthar; Milani, Anna M.; Cagliero, Cecilia; Rubiolo, Patrizia; Genre, Andrea; Cankar, Katarina; Beekwilder, Jules; Comino, Cinzia

2016-01-01

Globe artichoke (Cynara cardunculus L. var. scolymus) is a rich source of compounds promoting human health (phytonutrients), among them caffeoylquinic acids (CQAs), mainly represented by chlorogenic acid (CGA), and dicaffeoylquinic acids (diCQAs). The enzymes involved in their biosynthesis belong to the large family of BAHD acyltransferases. Following a survey of the globe artichoke genome, we identified 69 BAHD proteins carrying the catalytic site (HXXXD). Their phylogenetic analysis together with another 43 proteins, from 21 species, representative of the BAHD family, highlighted their grouping in seven major clades. Nine globe artichoke acyltransferases clustered in a sub-group of Clade V, with 3 belonging to hydroxycinnamoyl-CoA:quinate hydroxycinnamoyl transferase (HQT) and 2 to hydroxycinnamoyl-CoA:shikimate/quinate hydroxycinnamoyl transferase (HCT) like proteins. We focused our attention on the former, HQT1, HQT2, and HQT3, as they are known to play a key role in CGA biosynthesis. The expression of genes coding for the three HQTs and correlation of expression with the CQA content is reported for different globe artichoke tissues. For the first time in the globe artichoke, we developed and applied the virus-induced gene silencing approach with the goal of assessing in vivo the effect of HQT1 silencing, which resulted in a marked reduction of both CGA and diCQAs. On the other hand, when the role of the three HQTs was assessed in leaves of Nicotiana benthamiana through their transient overexpression, significant increases in mono- and diCQAs content were observed. Using transient GFP fusion proteins expressed in N. benthamiana leaves we also established the sub-cellular localization of these three enzymes. PMID:27721818

Sonic hedgehog promotes stem-cell potential of Mueller glia in the mammalian retina

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Wan Jin; Zheng Hua; Xiao Honglei; She Zhenjue; Zhou Guomin

2007-01-01

Mueller glia have been demonstrated to display stem-cell properties after retinal damage. Here, we report this potential can be regulated by Sonic hedgehog (Shh) signaling. Shh can stimulate proliferation of Mueller glia through its receptor and target gene expressed on them, furthermore, Shh-treated Mueller glia are induced to dedifferentiate by expressing progenitor-specific markers, and then adopt cell fate of rod photoreceptor. Inhibition of signaling by cyclopamine inhibits proliferation and dedifferentiation. Intraocular injection of Shh promotes Mueller glia activation in the photoreceptor-damaged retina, Shh also enhances neurogenic potential by producing more rhodopsin-positive photoreceptors from Mueller glia-derived cells. Together, these results provide evidences that Mueller glia act as potential stem cells in mammalian retina, Shh may have therapeutic effects on these cells for promoting the regeneration of retinal neurons

Sonic hedgehog promotes stem-cell potential of Mueller glia in the mammalian retina

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Jin, Wan; Hua, Zheng; Honglei, Xiao; Zhenjue, She [Department of Anatomy, Histology and Embryology, Shanghai Medical School, Fudan University, 200032 Shanghai (China); Zhou Guomin [Department of Anatomy, Histology and Embryology, Shanghai Medical School, Fudan University, 200032 Shanghai (China)], E-mail: gmzhou185@yahoo.com.cn

2007-11-16

Mueller glia have been demonstrated to display stem-cell properties after retinal damage. Here, we report this potential can be regulated by Sonic hedgehog (Shh) signaling. Shh can stimulate proliferation of Mueller glia through its receptor and target gene expressed on them, furthermore, Shh-treated Mueller glia are induced to dedifferentiate by expressing progenitor-specific markers, and then adopt cell fate of rod photoreceptor. Inhibition of signaling by cyclopamine inhibits proliferation and dedifferentiation. Intraocular injection of Shh promotes Mueller glia activation in the photoreceptor-damaged retina, Shh also enhances neurogenic potential by producing more rhodopsin-positive photoreceptors from Mueller glia-derived cells. Together, these results provide evidences that Mueller glia act as potential stem cells in mammalian retina, Shh may have therapeutic effects on these cells for promoting the regeneration of retinal neurons.

A five-gene hedgehog signature developed as a patient preselection tool for hedgehog inhibitor therapy in medulloblastoma.

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Shou, Yaping; Robinson, Douglas M; Amakye, Dereck D; Rose, Kristine L; Cho, Yoon-Jae; Ligon, Keith L; Sharp, Thad; Haider, Asifa S; Bandaru, Raj; Ando, Yuichi; Geoerger, Birgit; Doz, François; Ashley, David M; Hargrave, Darren R; Casanova, Michela; Tawbi, Hussein A; Rodon, Jordi; Thomas, Anne L; Mita, Alain C; MacDonald, Tobey J; Kieran, Mark W

2015-02-01

Distinct molecular subgroups of medulloblastoma, including hedgehog (Hh) pathway-activated disease, have been reported. We identified and clinically validated a five-gene Hh signature assay that can be used to preselect patients with Hh pathway-activated medulloblastoma. Gene characteristics of the Hh medulloblastoma subgroup were identified through published bioinformatic analyses. Thirty-two genes shown to be differentially expressed in fresh-frozen and formalin-fixed paraffin-embedded tumor samples and reproducibly analyzed by RT-PCR were measured in matched samples. These data formed the basis for building a multi-gene logistic regression model derived through elastic net methods from which the five-gene Hh signature emerged after multiple iterations. On the basis of signature gene expression levels, the model computed a propensity score to determine Hh activation using a threshold set a priori. The association between Hh activation status and tumor response to the Hh pathway inhibitor sonidegib (LDE225) was analyzed. Five differentially expressed genes in medulloblastoma (GLI1, SPHK1, SHROOM2, PDLIM3, and OTX2) were found to associate with Hh pathway activation status. In an independent validation study, Hh activation status of 25 medulloblastoma samples showed 100% concordance between the five-gene signature and Affymetrix profiling. Further, in medulloblastoma samples from 50 patients treated with sonidegib, all 6 patients who responded were found to have Hh-activated tumors. Three patients with Hh-activated tumors had stable or progressive disease. No patients with Hh-nonactivated tumors responded. This five-gene Hh signature can robustly identify Hh-activated medulloblastoma and may be used to preselect patients who might benefit from sonidegib treatment. ©2014 American Association for Cancer Research.

Map-based cloning and characterization of Zea mays male sterility33 (ZmMs33) gene, encoding a glycerol-3-phosphate acyltransferase.

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Xie, Ke; Wu, Suowei; Li, Ziwen; Zhou, Yan; Zhang, Danfeng; Dong, Zhenying; An, Xueli; Zhu, Taotao; Zhang, Simiao; Liu, Shuangshuang; Li, Jinping; Wan, Xiangyuan

2018-06-01

Map-based cloning of maize ms33 gene showed that ZmMs33 encodes a sn-2 glycerol-3-phosphate acyltransferase, the ortholog of rice OsGPAT3, and it is essential for male fertility in maize. Genetic male sterility has been widely studied for its biological significance and commercial value in hybrid seed production. Although many male-sterile mutants have been identified in maize (Zea mays L.), it is likely that most genes that cause male sterility are unknown. Here, we report a recessive genetic male-sterile mutant, male sterility33 (ms33), which displays small, pale yellow anthers, and complete male sterility. Using a map-based cloning approach, maize GRMZM2G070304 was identified as the ms33 gene (ZmMs33). ZmMs33 encodes a novel sn-2 glycerol-3-phosphate acyltransferase (GPAT) in maize. A functional complementation experiment showed that GRMZM2G070304 can rescue the male-sterile phenotype of the ms33-6029 mutant. GRMZM2G070304 was further confirmed to be the ms33 gene via targeted knockouts induced by the clustered regularly interspersed short palindromic repeats (CRISPR)/Cas9 system. ZmMs33 is preferentially expressed in the immature anther from the quartet to early-vacuolate microspore stages and in root tissues at the fifth leaf growth stage. Phylogenetic analysis indicated that ZmMs33 and OsGPAT3 are evolutionarily conserved for anther and pollen development in monocot species. This study reveals that the monocot-specific GPAT3 protein plays an important role in male fertility in maize, and ZmMs33 and mutants in this gene may have value in maize male-sterile line breeding and hybrid seed production.

Essential oil of Pinus koraiensis leaves exerts antihyperlipidemic effects via up-regulation of low-density lipoprotein receptor and inhibition of acyl-coenzyme A: cholesterol acyltransferase.

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Kim, Ji-Hyun; Lee, Hyo-Jung; Jeong, Soo-Jin; Lee, Min-Ho; Kim, Sung-Hoon

2012-09-01

Hyperlipidemia is an important factor to induce metabolic syndrome such as obesity, diabetes and cardiovascular diseases. Recently, some antihyperlipidemic agents from herbal medicines have been in the spotlight in the medical science field. Thus, the present study evaluated the antihyperlipidemic activities of the essential oil from the leaves of Pinus koraiensis SIEB (EOPK) that has been used as a folk remedy for heart disease. The reverse transcription polymerase chain reaction (RT-PCR) revealed that EOPK up-regulated low density lipoprotein receptor (LDLR) at the mRNA level as well as negatively suppressed the expression of sterol regulatory element-binding protein (SREBP)-1c, SREBP-2, 3-hydroxy-3-methyl-glutaryl-CoA reductase (HMGCR), fatty acid synthase (FAS) and glycerol-3-phosphate acyltransferase (GPAT) involved in lipid metabolism in HepG2 cells. Also, western blotting showed that EOPK activated LDLR and attenuated the expression of FAS at the protein level in the cells. Consistently, EOPK significantly inhibited the level of human acylcoenzyme A: cholesterol acyltransferase (hACAT)1 and 2 and reduced the low-density lipoprotein (LDL) oxidation activity. Furthermore, chromatography-mass spectrometry (GC-MS) analysis showed that EOPK, an essential oil mixture, contained camphene (21.11%), d-limonene (21.01%), α-pinene (16.74%) and borneol (11.52%). Overall, the findings suggest that EOPK can be a potent pharmaceutical agent for the prevention and treatment of hyperlipidemia. Copyright © 2012 John Wiley & Sons, Ltd.

Glycerol-3-phosphate Acyltransferase 1 Promotes Tumor Cell Migration and Poor Survival in Ovarian Carcinoma.

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Marchan, Rosemarie; Büttner, Bettina; Lambert, Jörg; Edlund, Karolina; Glaeser, Iris; Blaszkewicz, Meinolf; Leonhardt, Gregor; Marienhoff, Lisa; Kaszta, Darius; Anft, Moritz; Watzl, Carsten; Madjar, Katrin; Grinberg, Marianna; Rempel, Eugen; Hergenröder, Roland; Selinski, Silvia; Rahnenführer, Jörg; Lesjak, Michaela S; Stewart, Joanna D; Cadenas, Cristina; Hengstler, Jan G

2017-09-01

Glycerophosphodiesterase EDI3 (GPCPD1; GDE5; GDPD6) has been suggested to promote cell migration, adhesion, and spreading, but its mechanisms of action remain uncertain. In this study, we targeted the glycerol-3-phosphate acyltransferase GPAM along with choline kinase-α (CHKA), the enzymes that catabolize the products of EDI3 to determine which downstream pathway is relevant for migration. Our results clearly showed that GPAM influenced cell migration via the signaling lipid lysophosphatidic acid (LPA), linking it with GPAM to cell migration. Analysis of GPAM expression in different cancer types revealed a significant association between high GPAM expression and reduced overall survival in ovarian cancer. Silencing GPAM in ovarian cancer cells decreased cell migration and reduced the growth of tumor xenografts. In contrast to these observations, manipulating CHKA did not influence cell migration in the same set of cell lines. Overall, our findings show how GPAM influences intracellular LPA levels to promote cell migration and tumor growth. Cancer Res; 77(17); 4589-601. ©2017 AACR . ©2017 American Association for Cancer Research.

Gdf5 progenitors give rise to fibrocartilage cells that mineralize via hedgehog signaling to form the zonal enthesis.

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Dyment, Nathaniel A; Breidenbach, Andrew P; Schwartz, Andrea G; Russell, Ryan P; Aschbacher-Smith, Lindsey; Liu, Han; Hagiwara, Yusuke; Jiang, Rulang; Thomopoulos, Stavros; Butler, David L; Rowe, David W

2015-09-01

The sequence of events that leads to the formation of a functionally graded enthesis is not clearly defined. The current study demonstrates that clonal expansion of Gdf5 progenitors contributes to linear growth of the enthesis. Prior to mineralization, Col1+ cells in the enthesis appose Col2+ cells of the underlying primary cartilage. At the onset of enthesis mineralization, cells at the base of the enthesis express alkaline phosphatase, Indian hedgehog, and ColX as they mineralize. The mineralization front then extends towards the tendon midsubstance as cells above the front become encapsulated in mineralized fibrocartilage over time. The hedgehog (Hh) pathway regulates this process, as Hh-responsive Gli1+ cells within the developing enthesis mature from unmineralized to mineralized fibrochondrocytes in response to activated signaling. Hh signaling is required for mineralization, as tissue-specific deletion of its obligate transducer Smoothened in the developing tendon and enthesis cells leads to significant reductions in the apposition of mineralized fibrocartilage. Together, these findings provide a spatiotemporal map of events - from expansion of the embryonic progenitor pool to synthesis of the collagen template and finally mineralization of this template - that leads to the formation of the mature zonal enthesis. These results can inform future tendon-to-bone repair strategies to create a mechanically functional enthesis in which tendon collagen fibers are anchored to bone through mineralized fibrocartilage. Copyright © 2015 Elsevier Inc. All rights reserved.

Megalin functions as an endocytic sonic hedgehog receptor.

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McCarthy, Robert A; Barth, Jeremy L; Chintalapudi, Mastan R; Knaak, Christian; Argraves, W Scott

2002-07-12

Embryos deficient in the morphogen Sonic hedgehog (Shh) or the endocytic receptor megalin exhibit common neurodevelopmental abnormalities. Therefore, we have investigated the possibility that a functional relationship exists between the two proteins. During embryonic development, megalin was found to be expressed along the apical surfaces of neuroepithelial cells and was coexpressed with Shh in the ventral floor plate of the neural tube. Using enzyme-linked immunosorbent assay, homologous ligand displacement, and surface plasmon resonance techniques, it was found that the amino-terminal fragment of Shh (N-Shh) bound to megalin with high affinity. Megalin-expressing cells internalized N-Shh through a mechanism that was inhibited by antagonists of megalin, viz. anti-receptor-associated protein and anti-megalin antibodies. Heparin also inhibited N-Shh endocytosis, implicating proteoglycans in the internalization process, as has been described for other megalin ligands. Use of chloroquine to inhibit lysosomal proteinase activity showed that N-Shh endocytosed via megalin was not efficiently targeted to the lysosomes for degradation. The ability of megalin-internalized N-Shh to bypass lysosomes may relate to the finding that the interaction between N-Shh and megalin was resistant to dissociation with low pH. Together, these findings show that megalin is an efficient endocytic receptor for N-Shh. Furthermore, they implicate megalin as a new regulatory component of the Shh signaling pathway.

Genetic Analysis of Hedgehog Signaling in Ventral Body Wall Development and the Onset of Omphalocele Formation

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Matsumaru, Daisuke; Haraguchi, Ryuma; Miyagawa, Shinichi; Motoyama, Jun; Nakagata, Naomi; Meijlink, Frits; Yamada, Gen

2011-01-01

Background An omphalocele is one of the major ventral body wall malformations and is characterized by abnormally herniated viscera from the body trunk. It has been frequently found to be associated with other structural malformations, such as genitourinary malformations and digit abnormalities. In spite of its clinical importance, the etiology of omphalocele formation is still controversial. Hedgehog (Hh) signaling is one of the essential growth factor signaling pathways involved in the formation of the limbs and urogenital system. However, the relationship between Hh signaling and ventral body wall formation remains unclear. Methodology/Principal Findings To gain insight into the roles of Hh signaling in ventral body wall formation and its malformation, we analyzed phenotypes of mouse mutants of Sonic hedgehog (Shh), GLI-Kruppel family member 3 (Gli3) and Aristaless-like homeobox 4 (Alx4). Introduction of additional Alx4Lst mutations into the Gli3Xt/Xt background resulted in various degrees of severe omphalocele and pubic diastasis. In addition, loss of a single Shh allele restored the omphalocele and pubic symphysis of Gli3Xt/+; Alx4Lst/Lst embryos. We also observed ectopic Hh activity in the ventral body wall region of Gli3Xt/Xt embryos. Moreover, tamoxifen-inducible gain-of-function experiments to induce ectopic Hh signaling revealed Hh signal dose-dependent formation of omphaloceles. Conclusions/Significance We suggest that one of the possible causes of omphalocele and pubic diastasis is ectopically-induced Hh signaling. To our knowledge, this would be the first demonstration of the involvement of Hh signaling in ventral body wall malformation and the genetic rescue of omphalocele phenotypes. PMID:21283718

Genetic analysis of Hedgehog signaling in ventral body wall development and the onset of omphalocele formation.

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Daisuke Matsumaru

2011-01-01

Full Text Available An omphalocele is one of the major ventral body wall malformations and is characterized by abnormally herniated viscera from the body trunk. It has been frequently found to be associated with other structural malformations, such as genitourinary malformations and digit abnormalities. In spite of its clinical importance, the etiology of omphalocele formation is still controversial. Hedgehog (Hh signaling is one of the essential growth factor signaling pathways involved in the formation of the limbs and urogenital system. However, the relationship between Hh signaling and ventral body wall formation remains unclear.To gain insight into the roles of Hh signaling in ventral body wall formation and its malformation, we analyzed phenotypes of mouse mutants of Sonic hedgehog (Shh, GLI-Kruppel family member 3 (Gli3 and Aristaless-like homeobox 4 (Alx4. Introduction of additional Alx4(Lst mutations into the Gli3(Xt/Xt background resulted in various degrees of severe omphalocele and pubic diastasis. In addition, loss of a single Shh allele restored the omphalocele and pubic symphysis of Gli3(Xt/+; Alx4(Lst/Lst embryos. We also observed ectopic Hh activity in the ventral body wall region of Gli3(Xt/Xt embryos. Moreover, tamoxifen-inducible gain-of-function experiments to induce ectopic Hh signaling revealed Hh signal dose-dependent formation of omphaloceles.We suggest that one of the possible causes of omphalocele and pubic diastasis is ectopically-induced Hh signaling. To our knowledge, this would be the first demonstration of the involvement of Hh signaling in ventral body wall malformation and the genetic rescue of omphalocele phenotypes.

Indian Hedgehog Signaling Regulates Transcription and Expression of Collagen Type X via Runx2/Smads Interactions*

Science.gov (United States)

Amano, Katsuhiko; Densmore, Michael; Nishimura, Riko; Lanske, Beate

2014-01-01

Indian hedgehog (Ihh) is essential for chondrocyte differentiation and endochondral ossification and acts with parathyroid hormone-related peptide in a negative feedback loop to regulate early chondrocyte differentiation and entry to hypertrophic differentiation. Independent of this function, we and others recently reported independent Ihh functions to promote chondrocyte hypertrophy and matrix mineralization in vivo and in vitro. However, the molecular mechanisms for these actions and their functional significance are still unknown. We recently discovered that Ihh overexpression in chondrocytes stimulated the expression of late chondrocyte differentiation markers and induced matrix mineralization. Focusing on collagen type X (Col10α1) expression and transcription, we observed that hedgehog downstream transcription factors GLI-Krüppel family members (Gli) 1/2 increased COL10A1 promoter activity and identified a novel Gli1/2 response element in the 250-bp basic promoter. In addition, we found that Ihh induced Runx2 expression in chondrocytes without up-regulating other modulators of chondrocyte maturation such as Mef2c, Foxa2, and Foxa3. Runx2 promoted Col10α1 expression in cooperation with Ihh. Further analyses using promoter assays, immunofluorescence, and binding assays showed the interaction of Gli1/2 in a complex with Runx2/Smads induces chondrocyte differentiation. Finally, we could demonstrate that Ihh promotes in vitro matrix mineralization using similar molecular mechanisms. Our data provide an in vitro mechanism for Ihh signaling to positively regulate Col10α1 transcription. Thus, Ihh signaling could be an important player for not only early chondrocyte differentiation but maturation and calcification of chondrocytes. PMID:25028519

Knockdown of Indian hedgehog protein induces an inhibition of cell growth and differentiation in osteoblast MC3T3-E1 cells

OpenAIRE

Deng, Ang; Zhang, Hongqi; Hu, Minyu; Liu, Shaohua; Gao, Qile; Wang, Yuxiang; Guo, Chaofeng

2017-01-01

Indian hedgehog protein (Ihh) is evolutionarily conserved and serves important roles in controlling the differentiation of progenitor cells into osteoblasts. Ihh null mutant mice exhibit a failure of osteoblast development in endochondral bone. Although studies have demonstrated that Ihh signaling is a potent local factor that regulates osteoblast differentiation, the specific transcription factors that determine osteoblast differentiation remain unclear. Further studies are required to deter...

Identification of Alpha and Beta Coronavirus in Wildlife Species in France: Bats, Rodents, Rabbits, and Hedgehogs

Directory of Open Access Journals (Sweden)

Elodie Monchatre-Leroy

2017-11-01

Full Text Available Coronaviruses are closely monitored in the context of emerging diseases and, as illustrated with Severe Acute Respiratory Syndrome coronavirus (SARS-CoV and Middle East Respiratory Syndrome-coronavirus (MERS-CoV, are known to cross the species barrier and eventually to move from wildlife to humans. Knowledge of the diversity of coronaviruses in wildlife is therefore essential to better understand and prevent emergence events. This study explored the presence of coronaviruses in four wild mammal orders in France: Bats, rodents, lagomorphs, and hedgehogs. Betacoronavirus and Alphacoronavirus genera were identified. The results obtained suggest the circulation of potentially evolving virus strains, with the potential to cross the species barrier.

Ablating hedgehog signaling in tenocytes during development impairs biomechanics and matrix organization of the adult murine patellar tendon enthesis.

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Breidenbach, Andrew P; Aschbacher-Smith, Lindsey; Lu, Yinhui; Dyment, Nathaniel A; Liu, Chia-Feng; Liu, Han; Wylie, Chris; Rao, Marepalli; Shearn, Jason T; Rowe, David W; Kadler, Karl E; Jiang, Rulang; Butler, David L

2015-08-01

Restoring the native structure of the tendon enthesis, where collagen fibers of the midsubstance are integrated within a fibrocartilaginous structure, is problematic following injury. As current surgical methods fail to restore this region adequately, engineers, biologists, and clinicians are working to understand how this structure forms as a prerequisite to improving repair outcomes. We recently reported on the role of Indian hedgehog (Ihh), a novel enthesis marker, in regulating early postnatal enthesis formation. Here, we investigate how inactivating the Hh pathway in tendon cells affects adult (12-week) murine patellar tendon (PT) enthesis mechanics, fibrocartilage morphology, and collagen fiber organization. We show that ablating Hh signaling resulted in greater than 100% increased failure insertion strain (0.10 v. 0.05 mm/mm, p<0.01) as well as sub-failure biomechanical deficiencies. Although collagen fiber orientation appears overtly normal in the midsubstance, ablating Hh signaling reduces mineralized fibrocartilage by 32%, leading to less collagen embedded within mineralized tissue. Ablating Hh signaling also caused collagen fibers to coalesce at the insertion, which may explain in part the increased strains. These results indicate that Ihh signaling plays a critical role in the mineralization process of fibrocartilaginous entheses and may be a novel therapeutic to promote tendon-to-bone healing. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

Evaluation of WO2014207069 A1: Multitarget Hedgehog pathway inhibitors and uses thereof.

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Manetti, Fabrizio; Petricci, Elena

2016-01-01

In recent years, the involvement of the Hedgehog (Hh) signaling pathway in various human diseases and dysfunctions has been clearly demonstrated. Smoothened (Smo), one of the upstream signal transducers, has been the most druggable target of the Hh pathway. However, the emergence of resistance to Smo inhibitors and the identification of Smo-independent activation of the Hh pathway led to the need to find new chemical entities able to interfere with downstream components, such as Gli. For this purpose, two different computational approaches have been applied to a small-sized library of natural compounds. As a result, an isoflavone derivative that showed ability to inhibit both Smo and Gli1 has been identified; namely, Glabrescione B. A new synthetic approach has been planned for this compound and its derivatives. Biological evaluation demonstrated the mechanism of action and showed a promising preclinical profile.

Intricacies of hedgehog signaling pathways: A perspective in tumorigenesis

International Nuclear Information System (INIS)

Kar, Swayamsiddha; Deb, Moonmoon; Sengupta, Dipta; Shilpi, Arunima; Bhutia, Sujit Kumar; Patra, Samir Kumar

2012-01-01

The hedgehog (HH) signaling pathway is a crucial negotiator of developmental proceedings in the embryo governing a diverse array of processes including cell proliferation, differentiation, and tissue patterning. The overall activity of the pathway is significantly curtailed after embryogenesis as well as in adults, yet it retains many of its functional capacities. However, aberration in HH signaling mediates the initiation, proliferation and continued sustenance of malignancy in different tissues to varying degrees through different mechanisms. In this review, we provide an overview of the role of constitutively active aberrant HH signaling pathway in different types of human cancer and the underlying molecular and genetic mechanisms that drive tumorigenesis in that particular tissue. An insight into the various modes of anomalous HH signaling in different organs will provide a comprehensive knowledge of the pathway in these tissues and open a window for individually tailored, tissue-specific therapeutic interventions. The synergistic cross talking of HH pathway with many other regulatory molecules and developmentally inclined signaling pathways may offer many avenues for pharmacological advances. Understanding the molecular basis of abnormal HH signaling in cancer will provide an opportunity to inhibit the deregulated pathway in many aggressive and therapeutically challenging cancers where promising options are not available.

Intricacies of hedgehog signaling pathways: A perspective in tumorigenesis

Energy Technology Data Exchange (ETDEWEB)

Kar, Swayamsiddha; Deb, Moonmoon; Sengupta, Dipta; Shilpi, Arunima; Bhutia, Sujit Kumar [Epigenetics and Cancer Research Laboratory, Biochemistry and Molecular Biology Group, Department of Life Science, National Institute of Technology, Rourkela, Odisha 769008 (India); Patra, Samir Kumar, E-mail: samirp@nitrkl.ac.in [Epigenetics and Cancer Research Laboratory, Biochemistry and Molecular Biology Group, Department of Life Science, National Institute of Technology, Rourkela, Odisha 769008 (India)

2012-10-01

The hedgehog (HH) signaling pathway is a crucial negotiator of developmental proceedings in the embryo governing a diverse array of processes including cell proliferation, differentiation, and tissue patterning. The overall activity of the pathway is significantly curtailed after embryogenesis as well as in adults, yet it retains many of its functional capacities. However, aberration in HH signaling mediates the initiation, proliferation and continued sustenance of malignancy in different tissues to varying degrees through different mechanisms. In this review, we provide an overview of the role of constitutively active aberrant HH signaling pathway in different types of human cancer and the underlying molecular and genetic mechanisms that drive tumorigenesis in that particular tissue. An insight into the various modes of anomalous HH signaling in different organs will provide a comprehensive knowledge of the pathway in these tissues and open a window for individually tailored, tissue-specific therapeutic interventions. The synergistic cross talking of HH pathway with many other regulatory molecules and developmentally inclined signaling pathways may offer many avenues for pharmacological advances. Understanding the molecular basis of abnormal HH signaling in cancer will provide an opportunity to inhibit the deregulated pathway in many aggressive and therapeutically challenging cancers where promising options are not available.

Hedgehog pathway blockade with the cancer drug LDE225 disrupts taste organs and taste sensation.

Science.gov (United States)

Kumari, Archana; Ermilov, Alexandre N; Allen, Benjamin L; Bradley, Robert M; Dlugosz, Andrzej A; Mistretta, Charlotte M

2015-02-01

Taste sensation on the anterior tongue requires chorda tympani nerve function and connections with continuously renewing taste receptor cells. However, it is unclear which signaling pathways regulate the receptor cells to maintain chorda tympani sensation. Hedgehog (HH) signaling controls cell proliferation and differentiation in numerous tissues and is active in taste papillae and taste buds. In contrast, uncontrolled HH signaling drives tumorigenesis, including the common skin cancer, basal cell carcinoma. Systemic HH pathway inhibitors (HPIs) lead to basal cell carcinoma regression, but these drugs cause severe taste disturbances. We tested the hypothesis that taste disruption by HPIs reflects a direct requirement for HH signaling in maintaining taste organs and gustatory sensation. In mice treated with the HPI LDE225 up to 28 days, HH-responding cells were lost in fungiform papilla epithelium, and papillae acquired a conical apex. Taste buds were either absent or severely reduced in size in more than 90% of aberrant papillae. Taste bud remnants expressed the taste cell marker keratin 8, and papillae retained expression of nerve markers, neurofilament and P2X3. Chorda tympani nerve responses to taste stimuli were markedly reduced or absent in LDE225-treated mice. Responses to touch were retained, however, whereas cold responses were retained after 16 days of treatment but lost after 28 days. These data identify a critical, modality-specific requirement for HH signaling in maintaining taste papillae, taste buds and neurophysiological taste function, supporting the proposition that taste disturbances in HPI-treated patients are an on-target response to HH pathway blockade in taste organs. Copyright © 2015 the American Physiological Society.

Monoacylglycerol O-acyltransferase 1 is regulated by peroxisome proliferator-activated receptor γ in human hepatocytes and increases lipid accumulation

International Nuclear Information System (INIS)

Yu, Jung Hwan; Lee, Yoo Jeong; Kim, Hyo Jung; Choi, Hyeonjin; Choi, Yoonjeong; Seok, Jo Woon; Kim, Jae-woo

2015-01-01

Monoacylglycerol O-acyltransferase (MGAT) is an enzyme that is involved in triglyceride synthesis by catalyzing the formation of diacylglycerol from monoacylglycerol and fatty acyl CoAs. Recently, we reported that MGAT1 has a critical role in hepatic TG accumulation and that its suppression ameliorates hepatic steatosis in a mouse model. However, the function of MGAT enzymes in hepatic lipid accumulation has not been investigated in humans. Unlike in rodents, MGAT3 as well as MGAT1 and MGAT2 are present in humans. In this study, we evaluated the differences between MGAT subtypes and their association with peroxisome proliferator-activated receptor γ (PPARγ), a regulator of mouse MGAT1 expression. In human primary hepatocytes, basal expression of MGAT1 was lower than that of MGAT2 or MGAT3, but was strongly induced by PPARγ overexpression. A luciferase assay as well as an electromobility shift assay revealed that human MGAT1 promoter activity is driven by PPARγ by direct binding to at least two regions of the promoter in 293T and HepG2 cells. Moreover, siRNA-mediated suppression of MGAT1 expression significantly attenuated lipid accumulation by PPARγ overexpression in HepG2 cells, as evidenced by oil-red-O staining. These results suggest that human MGAT1 has an important role in fatty liver formation as a target gene of PPARγ, and blocking MGAT1 activity could be an efficient therapeutic way to reduce nonalcoholic fatty liver diseases in humans. - Highlights: • PPARγ promotes MGAT1 expression in human primary hepatocytes. • PPARγ directly regulates MGAT1 promoter activity. • Human MGAT1 promoter has at least two PPARγ-binding elements. • Inhibition of MGAT1 expression attenuates hepatic lipid accumulation in humans

Monoacylglycerol O-acyltransferase 1 is regulated by peroxisome proliferator-activated receptor γ in human hepatocytes and increases lipid accumulation

Energy Technology Data Exchange (ETDEWEB)

Yu, Jung Hwan [Department of Biochemistry and Molecular Biology, Integrated Genomic Research Center for Metabolic Regulation, Institute of Genetic Science, Yonsei University College of Medicine, Seoul 120-752 (Korea, Republic of); Brain Korea 21 PLUS Project for Medical Science, Yonsei University, Seoul 120-752 (Korea, Republic of); Lee, Yoo Jeong [Division of Metabolic Disease, Center for Biomedical Sciences, National Institutes of Health, Cheongwon-gun, Chungbuk 363-951 (Korea, Republic of); Kim, Hyo Jung; Choi, Hyeonjin [Department of Biochemistry and Molecular Biology, Integrated Genomic Research Center for Metabolic Regulation, Institute of Genetic Science, Yonsei University College of Medicine, Seoul 120-752 (Korea, Republic of); Choi, Yoonjeong; Seok, Jo Woon [Department of Biochemistry and Molecular Biology, Integrated Genomic Research Center for Metabolic Regulation, Institute of Genetic Science, Yonsei University College of Medicine, Seoul 120-752 (Korea, Republic of); Brain Korea 21 PLUS Project for Medical Science, Yonsei University, Seoul 120-752 (Korea, Republic of); Kim, Jae-woo, E-mail: japol13@yuhs.ac [Department of Biochemistry and Molecular Biology, Integrated Genomic Research Center for Metabolic Regulation, Institute of Genetic Science, Yonsei University College of Medicine, Seoul 120-752 (Korea, Republic of); Brain Korea 21 PLUS Project for Medical Science, Yonsei University, Seoul 120-752 (Korea, Republic of); Severance Biomedical Science Institute, Yonsei University College of Medicine, Seoul 120-752 (Korea, Republic of)

2015-05-08

Monoacylglycerol O-acyltransferase (MGAT) is an enzyme that is involved in triglyceride synthesis by catalyzing the formation of diacylglycerol from monoacylglycerol and fatty acyl CoAs. Recently, we reported that MGAT1 has a critical role in hepatic TG accumulation and that its suppression ameliorates hepatic steatosis in a mouse model. However, the function of MGAT enzymes in hepatic lipid accumulation has not been investigated in humans. Unlike in rodents, MGAT3 as well as MGAT1 and MGAT2 are present in humans. In this study, we evaluated the differences between MGAT subtypes and their association with peroxisome proliferator-activated receptor γ (PPARγ), a regulator of mouse MGAT1 expression. In human primary hepatocytes, basal expression of MGAT1 was lower than that of MGAT2 or MGAT3, but was strongly induced by PPARγ overexpression. A luciferase assay as well as an electromobility shift assay revealed that human MGAT1 promoter activity is driven by PPARγ by direct binding to at least two regions of the promoter in 293T and HepG2 cells. Moreover, siRNA-mediated suppression of MGAT1 expression significantly attenuated lipid accumulation by PPARγ overexpression in HepG2 cells, as evidenced by oil-red-O staining. These results suggest that human MGAT1 has an important role in fatty liver formation as a target gene of PPARγ, and blocking MGAT1 activity could be an efficient therapeutic way to reduce nonalcoholic fatty liver diseases in humans. - Highlights: • PPARγ promotes MGAT1 expression in human primary hepatocytes. • PPARγ directly regulates MGAT1 promoter activity. • Human MGAT1 promoter has at least two PPARγ-binding elements. • Inhibition of MGAT1 expression attenuates hepatic lipid accumulation in humans.

Structural insights into human Kif7, a kinesin involved in Hedgehog signalling

Energy Technology Data Exchange (ETDEWEB)

Klejnot, Marta, E-mail: m.klejnot@beatson.gla.ac.uk; Kozielski, Frank, E-mail: m.klejnot@beatson.gla.ac.uk [The Beatson Institute for Cancer Research, Garscube Estate, Switchback Road, Glasgow G61 1BD, Scotland (United Kingdom)

2012-02-01

The human Kif7 motor domain structure provides insights into a kinesin of medical significance. Kif7, a member of the kinesin 4 superfamily, is implicated in a variety of diseases including Joubert, hydrolethalus and acrocallosal syndromes. It is also involved in primary cilium formation and the Hedgehog signalling pathway and may play a role in cancer. Its activity is crucial for embryonic development. Kif7 and Kif27, a closely related kinesin in the same subfamily, are orthologues of the Drosophila melano@@gaster kinesin-like protein Costal-2 (Cos2). In vertebrates, they work together to fulfil the role of the single Cos2 gene in Drosophila. Here, the high-resolution structure of the human Kif7 motor domain is reported and is compared with that of conventional kinesin, the founding member of the kinesin superfamily. These data are a first step towards structural characterization of a kinesin-4 family member and of this interesting molecular motor of medical significance.

Tongue and Taste Organ Biology and Function: Homeostasis Maintained by Hedgehog Signaling.

Science.gov (United States)

Mistretta, Charlotte M; Kumari, Archana

2017-02-10

The tongue is an elaborate complex of heterogeneous tissues with taste organs of diverse embryonic origins. The lingual taste organs are papillae, composed of an epithelium that includes specialized taste buds, the basal lamina, and a lamina propria core with matrix molecules, fibroblasts, nerves, and vessels. Because taste organs are dynamic in cell biology and sensory function, homeostasis requires tight regulation in specific compartments or niches. Recently, the Hedgehog (Hh) pathway has emerged as an essential regulator that maintains lingual taste papillae, taste bud and progenitor cell proliferation and differentiation, and neurophysiological function. Activating or suppressing Hh signaling, with genetic models or pharmacological agents used in cancer treatments, disrupts taste papilla and taste bud integrity and can eliminate responses from taste nerves to chemical stimuli but not to touch or temperature. Understanding Hh regulation of taste organ homeostasis contributes knowledge about the basic biology underlying taste disruptions in patients treated with Hh pathway inhibitors.

Cholesterol activates the G-protein coupled receptor Smoothened to promote Hedgehog signaling

Science.gov (United States)

Luchetti, Giovanni; Sircar, Ria; Kong, Jennifer H; Nachtergaele, Sigrid; Sagner, Andreas; Byrne, Eamon FX; Covey, Douglas F; Siebold, Christian; Rohatgi, Rajat

2016-01-01

Cholesterol is necessary for the function of many G-protein coupled receptors (GPCRs). We find that cholesterol is not just necessary but also sufficient to activate signaling by the Hedgehog (Hh) pathway, a prominent cell-cell communication system in development. Cholesterol influences Hh signaling by directly activating Smoothened (SMO), an orphan GPCR that transmits the Hh signal across the membrane in all animals. Unlike many GPCRs, which are regulated by cholesterol through their heptahelical transmembrane domains, SMO is activated by cholesterol through its extracellular cysteine-rich domain (CRD). Residues shown to mediate cholesterol binding to the CRD in a recent structural analysis also dictate SMO activation, both in response to cholesterol and to native Hh ligands. Our results show that cholesterol can initiate signaling from the cell surface by engaging the extracellular domain of a GPCR and suggest that SMO activity may be regulated by local changes in cholesterol abundance or accessibility. DOI: http://dx.doi.org/10.7554/eLife.20304.001 PMID:27705744

The Role of Hedgehog Signaling in Tumor Induced Bone Disease

Directory of Open Access Journals (Sweden)

Shellese A. Cannonier

2015-08-01

Full Text Available Despite significant progress in cancer treatments, tumor induced bone disease continues to cause significant morbidities. While tumors show distinct mutations and clinical characteristics, they behave similarly once they establish in bone. Tumors can metastasize to bone from distant sites (breast, prostate, lung, directly invade into bone (head and neck or originate from the bone (melanoma, chondrosarcoma where they cause pain, fractures, hypercalcemia, and ultimately, poor prognoses and outcomes. Tumors in bone secrete factors (interleukins and parathyroid hormone-related protein that induce RANKL expression from osteoblasts, causing an increase in osteoclast mediated bone resorption. While the mechanisms involved varies slightly between tumor types, many tumors display an increase in Hedgehog signaling components that lead to increased tumor growth, therapy failure, and metastasis. The work of multiple laboratories has detailed Hh signaling in several tumor types and revealed that tumor establishment in bone can be controlled by both canonical and non-canonical Hh signaling in a cell type specific manner. This review will explore the role of Hh signaling in the modulation of tumor induced bone disease, and will shed insight into possible therapeutic interventions for blocking Hh signaling in these tumors.

The Role of Hedgehog Signaling in Tumor Induced Bone Disease

Energy Technology Data Exchange (ETDEWEB)

Cannonier, Shellese A.; Sterling, Julie A., E-mail: Julie.sterling@vanderbilt.edu [Department of Veterans Affairs, Tennessee Valley Healthcare System, Nashville, TN 37235 (United States); Vanderbilt Center for Bone Biology, Department of Medicine, Division of Clinical Pharmacology Vanderbilt University, Nashville, TN 372335 (United States); Department of Cancer Biology, Vanderbilt University, Nashville, TN 37235 (United States)

2015-08-26

Despite significant progress in cancer treatments, tumor induced bone disease continues to cause significant morbidities. While tumors show distinct mutations and clinical characteristics, they behave similarly once they establish in bone. Tumors can metastasize to bone from distant sites (breast, prostate, lung), directly invade into bone (head and neck) or originate from the bone (melanoma, chondrosarcoma) where they cause pain, fractures, hypercalcemia, and ultimately, poor prognoses and outcomes. Tumors in bone secrete factors (interleukins and parathyroid hormone-related protein) that induce RANKL expression from osteoblasts, causing an increase in osteoclast mediated bone resorption. While the mechanisms involved varies slightly between tumor types, many tumors display an increase in Hedgehog signaling components that lead to increased tumor growth, therapy failure, and metastasis. The work of multiple laboratories has detailed Hh signaling in several tumor types and revealed that tumor establishment in bone can be controlled by both canonical and non-canonical Hh signaling in a cell type specific manner. This review will explore the role of Hh signaling in the modulation of tumor induced bone disease, and will shed insight into possible therapeutic interventions for blocking Hh signaling in these tumors.

The Role of Hedgehog Signaling in Tumor Induced Bone Disease

International Nuclear Information System (INIS)

Cannonier, Shellese A.; Sterling, Julie A.

2015-01-01

Despite significant progress in cancer treatments, tumor induced bone disease continues to cause significant morbidities. While tumors show distinct mutations and clinical characteristics, they behave similarly once they establish in bone. Tumors can metastasize to bone from distant sites (breast, prostate, lung), directly invade into bone (head and neck) or originate from the bone (melanoma, chondrosarcoma) where they cause pain, fractures, hypercalcemia, and ultimately, poor prognoses and outcomes. Tumors in bone secrete factors (interleukins and parathyroid hormone-related protein) that induce RANKL expression from osteoblasts, causing an increase in osteoclast mediated bone resorption. While the mechanisms involved varies slightly between tumor types, many tumors display an increase in Hedgehog signaling components that lead to increased tumor growth, therapy failure, and metastasis. The work of multiple laboratories has detailed Hh signaling in several tumor types and revealed that tumor establishment in bone can be controlled by both canonical and non-canonical Hh signaling in a cell type specific manner. This review will explore the role of Hh signaling in the modulation of tumor induced bone disease, and will shed insight into possible therapeutic interventions for blocking Hh signaling in these tumors

Processing and turnover of the Hedgehog protein in the endoplasmic reticulum.

Science.gov (United States)

Chen, Xin; Tukachinsky, Hanna; Huang, Chih-Hsiang; Jao, Cindy; Chu, Yue-Ru; Tang, Hsiang-Yun; Mueller, Britta; Schulman, Sol; Rapoport, Tom A; Salic, Adrian

2011-03-07

The Hedgehog (Hh) signaling pathway has important functions during metazoan development. The Hh ligand is generated from a precursor by self-cleavage, which requires a free cysteine in the C-terminal part of the protein and results in the production of the cholesterol-modified ligand and a C-terminal fragment. In this paper, we demonstrate that these reactions occur in the endoplasmic reticulum (ER). The catalytic cysteine needs to form a disulfide bridge with a conserved cysteine, which is subsequently reduced by protein disulfide isomerase. Generation of the C-terminal fragment is followed by its ER-associated degradation (ERAD), providing the first example of an endogenous luminal ERAD substrate that is constitutively degraded. This process requires the ubiquitin ligase Hrd1, its partner Sel1, the cytosolic adenosine triphosphatase p97, and degradation by the proteasome. Processing-defective mutants of Hh are degraded by the same ERAD components. Thus, processing of the Hh precursor competes with its rapid degradation, explaining the impaired Hh signaling of processing-defective mutants, such as those causing human holoprosencephaly.

Role of GSK-3β in the osteogenic differentiation of palatal mesenchyme.

Directory of Open Access Journals (Sweden)

Emily R Nelson

Full Text Available INTRODUCTION: The function of Glycogen Synthase Kinases 3β (GSK-3β has previously been shown to be necessary for normal secondary palate development. Using GSK-3ß null mouse embryos, we examine the potential coordinate roles of Wnt and Hedgehog signaling on palatal ossification. METHODS: Palates were harvested from GSK-3β, embryonic days 15.0-18.5 (e15.0-e18.5, and e15.5 Indian Hedgehog (Ihh null embryos, and their wild-type littermates. The phenotype of GSK-3β null embryos was analyzed with skeletal whole mount and pentachrome stains. Spatiotemporal regulation of osteogenic gene expression, in addition to Wnt and Hedgehog signaling activity, were examined in vivo on GSK-3β and Ihh +/+ and -/- e15.5 embryos using in situ hybridization and immunohistochemistry. To corroborate these results, expression of the same molecular targets were assessed by qRT-PCR of e15.5 palates, or e13.5 palate cultures treated with both Wnt and Hedgehog agonists and anatagonists. RESULTS: GSK-3β null embryos displayed a 48 percent decrease (*p<0.05 in palatine bone formation compared to wild-type littermates. GSK-3β null embryos also exhibited decreased osteogenic gene expression that was associated with increased Wnt and decreased Hedgehog signaling. e13.5 palate culture studies demonstrated that Wnt signaling negatively regulates both osteogenic gene expression and Hedgehog signaling activity, while inhibition of Wnt signaling augments both osteogenic gene expression and Hedgehog signaling activity. In addition, no differences in Wnt signaling activity were noted in Ihh null embryos, suggesting that canonical Wnt may be upstream of Hedgehog in secondary palate development. Lastly, we found that GSK-3β -/- palate cultures were "rescued" with the Wnt inhibitor, Dkk-1. CONCLUSIONS: Here, we identify a critical role for GSK-3β in palatogenesis through its direct regulation of canonical Wnt signaling. These findings shed light on critical developmental pathways

Identification and Validation of Novel Hedgehog-Responsive Enhancers Predicted by Computational Analysis of Ci/Gli Binding Site Density

Science.gov (United States)

Richards, Neil; Parker, David S.; Johnson, Lisa A.; Allen, Benjamin L.; Barolo, Scott; Gumucio, Deborah L.

2015-01-01

The Hedgehog (Hh) signaling pathway directs a multitude of cellular responses during embryogenesis and adult tissue homeostasis. Stimulation of the pathway results in activation of Hh target genes by the transcription factor Ci/Gli, which binds to specific motifs in genomic enhancers. In Drosophila, only a few enhancers (patched, decapentaplegic, wingless, stripe, knot, hairy, orthodenticle) have been shown by in vivo functional assays to depend on direct Ci/Gli regulation. All but one (orthodenticle) contain more than one Ci/Gli site, prompting us to directly test whether homotypic clustering of Ci/Gli binding sites is sufficient to define a Hh-regulated enhancer. We therefore developed a computational algorithm to identify Ci/Gli clusters that are enriched over random expectation, within a given region of the genome. Candidate genomic regions containing Ci/Gli clusters were functionally tested in chicken neural tube electroporation assays and in transgenic flies. Of the 22 Ci/Gli clusters tested, seven novel enhancers (and the previously known patched enhancer) were identified as Hh-responsive and Ci/Gli-dependent in one or both of these assays, including: Cuticular protein 100A (Cpr100A); invected (inv), which encodes an engrailed-related transcription factor expressed at the anterior/posterior wing disc boundary; roadkill (rdx), the fly homolog of vertebrate Spop; the segment polarity gene gooseberry (gsb); and two previously untested regions of the Hh receptor-encoding patched (ptc) gene. We conclude that homotypic Ci/Gli clustering is not sufficient information to ensure Hh-responsiveness; however, it can provide a clue for enhancer recognition within putative Hedgehog target gene loci. PMID:26710299

Expression of tung tree diacylglycerol acyltransferase 1 in E. coli

Directory of Open Access Journals (Sweden)

Klasson K Thomas

2011-07-01

Full Text Available Abstract Background Diacylglycerol acyltransferases (DGATs catalyze the final and rate-limiting step of triacylglycerol (TAG biosynthesis in eukaryotic organisms. Database search has identified at least 59 DGAT1 sequences from 48 organisms, but the expression of any DGAT1 as a full-length protein in E. coli had not been reported because DGAT1s are integral membrane proteins and difficult to express and purify. The objective of this study was to establish a procedure for expressing full-length DGAT1 in E. coli. Results An expression plasmid containing the open reading frame for tung tree (Vernicia fordii DGAT1 fused to maltose binding protein and poly-histidine affinity tags was constructed and expressed in E. coli BL21(DE3. Immunoblotting showed that the recombinant DGAT1 (rDGAT1 was expressed, but mostly targeted to the membranes and insoluble fractions. Extensive degradation also occurred. Nonetheless, the fusion protein was partially purified from the soluble fraction by Ni-NTA and amylose resin affinity chromatography. Multiple proteins co-purified with DGAT1 fusion protein. These fractions appeared yellow in color and contained fatty acids. The rDGAT1 was solubilized from the insoluble fraction by seven detergents and urea, with SDS and Triton X-100 being the most effective detergents. The solubilized rDGAT1 was partially purified by Ni-NTA affinity chromatography. PreScission protease digestion confirmed the identity of rDGAT1 and showed extensive precipitation following Ni-NTA affinity purification. Conclusions This study reports the first procedure for expressing full-length DGAT1 from any species using a bacterial expression system. The results suggest that recombinant DGAT1 is degraded extensively from the carboxyl terminus and associated with other proteins, lipids, and membranes.

Concerted elevation of acyl-coenzyme A:diacylglycerol acyltransferase (DGAT) activity through independent stimulation of mRNA expression of DGAT1 and DGAT2 by carbohydrate and insulin.

Science.gov (United States)

Meegalla, Rupalie L; Billheimer, Jeffrey T; Cheng, Dong

2002-11-01

Glucose and insulin are anabolic signals which upregulate the transcriptions of a series of lipogenic enzymes to convert excess carbohydrate into triglycerides for efficient energy storage. These enzymes include ATP-citrate lyase (ACL), acetyl-coenzyme A carboxylase (ACC), fatty acid synthase (FAS), and glycerol-3-phosphate acyltransferase (G3PA). Acyl-coenzyme A:diacylglycerol acyltransferase (DGAT) is important to synthesize fatty acids into triglycerides. Two DGATs from different gene families have recently been identified. In the current study, we report that glucose preferentially enhances DGAT1 mRNA expression, whereas insulin specifically increases the level of DGAT2 mRNA. Treatment of adipocytes with glucose and insulin together results in higher DGAT activity in the membrane than cells treated with either of the agents alone, indicating that glucose and insulin have additive effect on DGAT activation. In mice treated with fast/refeeding protocol, DGAT2 mRNA decreased upon fasting and was replenished upon refeeding in adipose tissue and liver. This pattern of change was not observed for DGAT1. Inasmuch as DGAT1 mRNA is less abundant in liver, we suggest that DGAT1 is more involved in fat absorption in the intestine and in basal level triglyceride synthesis in adipose tissue where it is more highly expressed. In contrast, DGAT2 is more likely to play important roles in assembly of de novo synthesized fatty acids into VLDL particles in the liver.

[Development of Holistic Cancer Treatment Centering Cancer Patients - From the Standpoint of Hypoxia and Hedgehog Signaling].

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Onishi, Hideya; Ogino, Toshitatsu; Morisaki, Takashi; Katano, Mitsuo

2017-11-01

Recently, hypoxia that is one of cancer microenvironments, takes much attention. Because circumstance that we usually perform experiment is 20% O2 condition, it is likely that different signaling pathways may be activated in vivo cancer. We focused Hedgehog(Hh)signaling as one of activated pathways under hypoxia. It has been shown that Hh signaling is activated under hypoxia, followed by inducing malignant phenotypes in pancreatic cancer. Therefore, Hh signaling inhibitor should elicit anti-tumor effect. However, if we consider "whole-person therapy" we should confirm how Hh signaling affects the function of immune cells. In the present study, we describe hypoxia/Hh signaling/functions of cancer cells and immune cells focusing our previous results.

Pituitary Adenylate Cyclase Activating Polypeptide (PACAP) Pathway Is Induced by Mechanical Load and Reduces the Activity of Hedgehog Signaling in Chondrogenic Micromass Cell Cultures

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Juhász, Tamás; Szentléleky, Eszter; Szűcs Somogyi, Csilla; Takács, Roland; Dobrosi, Nóra; Engler, Máté; Tamás, Andrea; Reglődi, Dóra; Zákány, Róza

2015-01-01

Pituitary adenylate cyclase activating polypeptide (PACAP) is a neurohormone exerting protective function during various stress conditions either in mature or developing tissues. Previously we proved the presence of PACAP signaling elements in chicken limb bud-derived chondrogenic cells in micromass cell cultures. Since no data can be found if PACAP signaling is playing any role during mechanical stress in any tissues, we aimed to investigate its contribution in mechanotransduction during chondrogenesis. Expressions of the mRNAs of PACAP and its major receptor, PAC1 increased, while that of other receptors, VPAC1, VPAC2 decreased upon mechanical stimulus. Mechanical load enhanced the expression of collagen type X, a marker of hypertrophic differentiation of chondrocytes and PACAP addition attenuated this elevation. Moreover, exogenous PACAP also prevented the mechanical load evoked activation of hedgehog signaling: protein levels of Sonic and Indian Hedgehogs and Gli1 transcription factor were lowered while expressions of Gli2 and Gli3 were elevated by PACAP application during mechanical load. Our results suggest that mechanical load activates PACAP signaling and exogenous PACAP acts against the hypertrophy inducing effect of mechanical load. PMID:26230691

Pituitary Adenylate Cyclase Activating Polypeptide (PACAP Pathway Is Induced by Mechanical Load and Reduces the Activity of Hedgehog Signaling in Chondrogenic Micromass Cell Cultures

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Tamás Juhász

2015-07-01

Full Text Available Pituitary adenylate cyclase activating polypeptide (PACAP is a neurohormone exerting protective function during various stress conditions either in mature or developing tissues. Previously we proved the presence of PACAP signaling elements in chicken limb bud-derived chondrogenic cells in micromass cell cultures. Since no data can be found if PACAP signaling is playing any role during mechanical stress in any tissues, we aimed to investigate its contribution in mechanotransduction during chondrogenesis. Expressions of the mRNAs of PACAP and its major receptor, PAC1 increased, while that of other receptors, VPAC1, VPAC2 decreased upon mechanical stimulus. Mechanical load enhanced the expression of collagen type X, a marker of hypertrophic differentiation of chondrocytes and PACAP addition attenuated this elevation. Moreover, exogenous PACAP also prevented the mechanical load evoked activation of hedgehog signaling: protein levels of Sonic and Indian Hedgehogs and Gli1 transcription factor were lowered while expressions of Gli2 and Gli3 were elevated by PACAP application during mechanical load. Our results suggest that mechanical load activates PACAP signaling and exogenous PACAP acts against the hypertrophy inducing effect of mechanical load.

The enzyme lecithin-cholesterol acyltransferase esterifies cerebrosterol and limits the toxic effect of this oxysterol on SH-SY5Y cells.

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La Marca, Valeria; Spagnuolo, Maria Stefania; Cigliano, Luisa; Marasco, Daniela; Abrescia, Paolo

2014-07-01

Cholesterol is mostly removed from the CNS by its conversion to cerebrosterol (24(S)-hydroxycholesterol, 24(S)OH-C), which is transported to the circulation for bile formation in liver. A neurotoxic role of this oxysterol was previously demonstrated in cell culture. Here, we provide evidence that the enzyme lecithin-cholesterol acyltransferase, long known to esterify cholesterol, also produces monoesters of 24(S)OH-C. Proteoliposomes containing apolipoprotein A-I or apolipoprotein E were used to stimulate the enzyme activity and entrap the formed esters. Proteoliposomes with apolipoprotein A-I were found to be more active than those with apolipoprotein E in stimulating the production of oxysteryl esters. Cholesterol and 24(S)OH-C were found to compete for enzyme activity. High levels of haptoglobin, as those circulating during the acute inflammatory phase, inhibited 24(S)OH-C esterification. When highly neurotoxic 24(S)OH-C was treated with enzyme and proteoliposomes before incubation with differentiated SH-SY5Y cells, the neuron survival improved. The esters of 24(S)OH-C, embedded into proteoliposomes by the enzyme and isolated from unesterified 24(S)OH-C by gel filtration chromatography, did not enter the neurons in culture. These results suggest that the enzyme, in the presence of the apolipoproteins, converts 24(S)OH-C into esters restricted to the extracellular environment, thus preventing or limiting oxysterol-induced neurotoxic injuries to neurons in culture. 24-hydroxycholesterol (24(S)OH-C) is neurotoxic. The enzyme lecithin-cholesterol acyltransferase (LCAT) synthesizes monoesters of 24(S)OH-C in reaction mixtures with proteoliposomes containing phospholipids and apolipoprotein A-I or apolipoprotein E. The esters, also produced by incubation of cerebrospinal fluid only with tritiated 24(S)OH-C, are embedded into lipoproteins that do not enter neurons in culture. The enzyme activity limits the toxicity of 24-hydroxycholesterol in neuron culture. © 2014

Temporomandibular joint formation requires two distinct hedgehog-dependent steps.

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Purcell, Patricia; Joo, Brian W; Hu, Jimmy K; Tran, Pamela V; Calicchio, Monica L; O'Connell, Daniel J; Maas, Richard L; Tabin, Clifford J

2009-10-27

We conducted a genetic analysis of the developing temporo-mandibular or temporomandi-bular joint (TMJ), a highly specialized synovial joint that permits movement and function of the mammalian jaw. First, we used laser capture microdissection to perform a genome-wide expression analysis of each of its developing components. The expression patterns of genes identified in this screen were examined in the TMJ and compared with those of other synovial joints, including the shoulder and the hip joints. Striking differences were noted, indicating that the TMJ forms via a distinct molecular program. Several components of the hedgehog (Hh) signaling pathway are among the genes identified in the screen, including Gli2, which is expressed specifically in the condyle and in the disk of the developing TMJ. We found that mice deficient in Gli2 display aberrant TMJ development such that the condyle loses its growth-plate-like cellular organization and no disk is formed. In addition, we used a conditional strategy to remove Smo, a positive effector of the Hh signaling pathway, from chondrocyte progenitors. This cell autonomous loss of Hh signaling allows for disk formation, but the resulting structure fails to separate from the condyle. Thus, these experiments establish that Hh signaling acts at two distinct steps in disk morphogenesis, condyle initiation, and disk-condyle separation and provide a molecular framework for future studies of the TMJ.

Hedgehog pathway activity in the LADY prostate tumor model

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Kasper Susan

2007-03-01

Full Text Available Abstract Background Robust Hedgehog (Hh signaling has been implicated as a common feature of human prostate cancer and an important stimulus of tumor growth. The role of Hh signaling has been studied in several xenograft tumor models, however, the role of Hh in tumor development in a transgenic prostate cancer model has never been examined. Results We analyzed expression of Hh pathway components and conserved Hh target genes along with progenitor cell markers and selected markers of epithelial differentiation during tumor development in the LADY transgenic mouse model. Tumor development was associated with a selective increase in Ihh expression. In contrast Shh expression was decreased. Expression of the Hh target Patched (Ptc was significantly decreased while Gli1 expression was not significantly altered. A survey of other relevant genes revealed significant increases in expression of Notch-1 and Nestin together with decreased expression of HNF3a/FoxA1, NPDC-1 and probasin. Conclusion Our study shows no evidence for a generalized increase in Hh signaling during tumor development in the LADY mouse. It does reveal a selective increase in Ihh expression that is associated with increased expression of progenitor cell markers and decreased expression of terminal differentiation markers. These data suggest that Ihh expression may be a feature of a progenitor cell population that is involved in tumor development.

Foretinib is effective therapy for metastatic sonic hedgehog medulloblastoma.

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Faria, Claudia C; Golbourn, Brian J; Dubuc, Adrian M; Remke, Marc; Diaz, Roberto J; Agnihotri, Sameer; Luck, Amanda; Sabha, Nesrin; Olsen, Samantha; Wu, Xiaochong; Garzia, Livia; Ramaswamy, Vijay; Mack, Stephen C; Wang, Xin; Leadley, Michael; Reynaud, Denis; Ermini, Leonardo; Post, Martin; Northcott, Paul A; Pfister, Stefan M; Croul, Sidney E; Kool, Marcel; Korshunov, Andrey; Smith, Christian A; Taylor, Michael D; Rutka, James T

2015-01-01

Medulloblastoma is the most common malignant pediatric brain tumor, with metastases present at diagnosis conferring a poor prognosis. Mechanisms of dissemination are poorly understood and metastatic lesions are genetically divergent from the matched primary tumor. Effective and less toxic therapies that target both compartments have yet to be identified. Here, we report that the analysis of several large nonoverlapping cohorts of patients with medulloblastoma reveals MET kinase as a marker of sonic hedgehog (SHH)-driven medulloblastoma. Immunohistochemical analysis of phosphorylated, active MET kinase in an independent patient cohort confirmed its correlation with increased tumor relapse and poor survival, suggesting that patients with SHH medulloblastoma may benefit from MET-targeted therapy. In support of this hypothesis, we found that the approved MET inhibitor foretinib could suppress MET activation, decrease tumor cell proliferation, and induce apoptosis in SHH medulloblastomas in vitro and in vivo. Foretinib penetrated the blood-brain barrier and was effective in both the primary and metastatic tumor compartments. In established mouse xenograft or transgenic models of metastatic SHH medulloblastoma, foretinib administration reduced the growth of the primary tumor, decreased the incidence of metastases, and increased host survival. Taken together, our results provide a strong rationale to clinically evaluate foretinib as an effective therapy for patients with SHH-driven medulloblastoma. ©2014 American Association for Cancer Research.

Indian Hedgehog signaling pathway members are associated with magnetic resonance imaging manifestations and pathological scores in lumbar facet joint osteoarthritis

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Shuang, Feng; Zhou, Ying; Hou, Shu-Xun; Zhu, Jia-Liang; Liu, Yan; Zhang, Chun-Li; Tang, Jia-Guang

2015-05-01

Indian Hedgehog (HH) has been shown to be involved in osteoarthritis (OA) in articular joints, where there is evidence that Indian HH blockade could ameliorate OA. It seems to play a prominent role in development of the intervertebral disc (IVD) and in postnatal maintenance. There is little work on IHH in the IVD. Hence the aim of the current study was to investigate the role of Indian Hedgehog in the pathology of facet joint (FJ) OA. 24 patients diagnosed with lumbar intervertebral disk herniation or degenerative spinal stenosis were included. Preoperative magnetic resonance imaging (MRI) and Osteoarthritis Research Society International (OARSI) histopathology grading system was correlated to the mRNA levels of GLI1, PTCH1, and HHIP in the FJs. The Weishaupt grading and OARSI scores showed high positive correlation (r = 0.894) (P < 0.01). MRI Weishaupt grades showed positive correlation with GLI1 (r = 0.491), PTCH1 (r = 0.444), and HHIP (r = 0.654) mRNA levels (P < 0.05 in each case). OARSI scores were also positively correlated with GLI1 (r = 0. 646), PTCH1 (r = 0. 518), and HHIP (r = 0.762) mRNA levels (P < 0.01 in each case). Cumulatively our findings indicate that Indian HH signaling is increased in OA and is perhaps a key component in OA pathogenesis and progression.

Effect of deregulation of Sonic Hedgehog pathway on responses to DNA damage and cancer predisposition

International Nuclear Information System (INIS)

Charazac, Aurelie

2015-01-01

The Gorlin syndrome is a rare genetic disorder characterized by several developmental abnormalities. Due to mutations in PTCH1, a key player of the sonic hedgehog signaling pathway, clinical manifestations also includes hyper-radiosensitivity and an increased predisposition to the development of basal cell carcinomas. Given the implication of DNA repair system defects in hyper-radiosensitivity pathologies, we decided to study the effect of PTCH1 mutations on the DNA damage response in order to better understand the cellular and molecular mechanisms leading to Gorlin's phenotype.This study demonstrate a global failure of the DNA damage repair systems in Gorlin fibroblasts with respect to controls. It highlights in particular the collapse of the base excision repair pathway (BER) responsible for the repair of oxidative DNA damage. (author) [fr

Hedgehog pathway as a potential treatment target in human cholangiocarcinoma.

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Riedlinger, Dorothee; Bahra, Marcus; Boas-Knoop, Sabine; Lippert, Steffen; Bradtmöller, Maren; Guse, Katrin; Seehofer, Daniel; Bova, Roberta; Sauer, Igor M; Neuhaus, Peter; Koch, Arend; Kamphues, Carsten

2014-08-01

Innovative treatment concepts targeting essential signaling pathways may offer new chances for patients suffering from cholangiocarcinoma (CCC). For that, we performed a systematic molecular genetic analysis concerning the Hedgehog activity in human CCC samples and analyzed the effect of Hh inhibition on CCC cells in vitro and in vivo. Activation of the Hh pathway was analyzed in 50 human CCC samples using quantitative polymerase chain reaction (qPCR). The efficacy of Hh inhibition using cyclopamine and BMS-833923 was evaluated in vitro. In addition, the effect of BMS-833923, alone or in combination with gemcitabine, was analyzed in vivo in a murine subcutaneous xenograft model. Expression analysis revealed a significant activation of the Hh-signaling pathway in nearly 50% of CCCs. Hh inhibition resulted in a significant decrease in cell proliferation of CCC cells. Moreover, a distinct inhibition of tumor growth could be seen as a result of a combined therapy with BMS-833923 and gemcitabine in CCC xenografts. The results of our study suggest that the Hh pathway plays a relevant role at least in a subset of human CCC. Inhibition of this pathway may represent a possible treatment option for CCC patients in which the Hh pathway is activated. © 2014 Japanese Society of Hepato-Biliary-Pancreatic Surgery.

Microscale High-Throughput Experimentation as an Enabling Technology in Drug Discovery: Application in the Discovery of (Piperidinyl)pyridinyl-1H-benzimidazole Diacylglycerol Acyltransferase 1 Inhibitors.

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Cernak, Tim; Gesmundo, Nathan J; Dykstra, Kevin; Yu, Yang; Wu, Zhicai; Shi, Zhi-Cai; Vachal, Petr; Sperbeck, Donald; He, Shuwen; Murphy, Beth Ann; Sonatore, Lisa; Williams, Steven; Madeira, Maria; Verras, Andreas; Reiter, Maud; Lee, Claire Heechoon; Cuff, James; Sherer, Edward C; Kuethe, Jeffrey; Goble, Stephen; Perrotto, Nicholas; Pinto, Shirly; Shen, Dong-Ming; Nargund, Ravi; Balkovec, James; DeVita, Robert J; Dreher, Spencer D

2017-05-11

Miniaturization and parallel processing play an important role in the evolution of many technologies. We demonstrate the application of miniaturized high-throughput experimentation methods to resolve synthetic chemistry challenges on the frontlines of a lead optimization effort to develop diacylglycerol acyltransferase (DGAT1) inhibitors. Reactions were performed on ∼1 mg scale using glass microvials providing a miniaturized high-throughput experimentation capability that was used to study a challenging S N Ar reaction. The availability of robust synthetic chemistry conditions discovered in these miniaturized investigations enabled the development of structure-activity relationships that ultimately led to the discovery of soluble, selective, and potent inhibitors of DGAT1.

FGFR3 Deficiency Causes Multiple Chondroma-like Lesions by Upregulating Hedgehog Signaling.

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Siru Zhou

2015-06-01

Full Text Available Most cartilaginous tumors are formed during skeletal development in locations adjacent to growth plates, suggesting that they arise from disordered endochondral bone growth. Fibroblast growth factor receptor (FGFR3 signaling plays essential roles in this process; however, the role of FGFR3 in cartilaginous tumorigenesis is not known. In this study, we found that postnatal chondrocyte-specific Fgfr3 deletion induced multiple chondroma-like lesions, including enchondromas and osteochondromas, adjacent to disordered growth plates. The lesions showed decreased extracellular signal-regulated kinase (ERK activity and increased Indian hedgehog (IHH expression. The same was observed in Fgfr3-deficient primary chondrocytes, in which treatment with a mitogen-activated protein kinase (MEK inhibitor increased Ihh expression. Importantly, treatment with an inhibitor of IHH signaling reduced the occurrence of chondroma-like lesions in Fgfr3-deficient mice. This is the first study reporting that the loss of Fgfr3 function leads to the formation of chondroma-like lesions via downregulation of MEK/ERK signaling and upregulation of IHH, suggesting that FGFR3 has a tumor suppressor-like function in chondrogenesis.

Sonic Hedgehog Initiates Cochlear Hair Cell Regeneration through Downregulation of Retinoblastoma Protein

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Lu, Na; Chen, Yan; Wang, Zhengmin; Chen, Guoling; Lin, Qin; Chen, Zheng-Yi; Li, Huawei

2013-01-01

Cell cycle re-entry by cochlear supporting cells and/or hair cells is considered one of the best approaches for restoring hearing loss as a result of hair cell damage. To identify mechanisms that can be modulated to initiate cell cycle re-entry and hair cell regeneration, we studied the effect of activating the sonic hedgehog (Shh) pathway. We show that Shh signaling in postnatal rat cochleae damaged by neomycin leads to renewed proliferation of supporting cells and hair cells. Further, proliferating supporting cells are likely to transdifferentiate into hair cells. Shh treatment leads to inhibition of retinoblastoma protein (pRb) by increasing phosphorylated pRb and reducing retinoblastoma gene transcription. This results in upregulation of cyclins B1, D2, and D3, and CDK1. These results suggest that Shh signaling induces cell cycle re-entry in cochlear sensory epithelium and the production of new hair cells, in part by attenuating pRb function. This study provides an additional route to modulate pRb function with important implications in mammalian hair cell regeneration. PMID:23211596

N-docosahexaenoylethanolamine regulates Hedgehog signaling and promotes growth of cortical axons

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Giorgi Kharebava

2015-12-01

Full Text Available Axonogenesis, a process for the establishment of neuron connectivity, is central to brain function. The role of metabolites derived from docosahexaenoic acid (DHA, 22:6n-3 that is specifically enriched in the brain, has not been addressed in axon development. In this study, we tested if synaptamide (N-docosahexaenoylethanolamine, an endogenous metabolite of DHA, affects axon growth in cultured cortical neurons. We found that synaptamide increased the average axon length, inhibited GLI family zinc finger 1 (GLI1 transcription and sonic hedgehog (Shh target gene expression while inducing cAMP elevation. Similar effects were produced by cyclopamine, a regulator of the Shh pathway. Conversely, Shh antagonized elevation of cAMP and blocked synaptamide-mediated increase in axon length. Activation of Shh pathway by a smoothened (SMO agonist (SAG or overexpression of SMO did not inhibit axon growth mediated by synaptamide or cyclopamine. Instead, adenylate cyclase inhibitor SQ22536 abolished synaptamide-mediated axon growth indicating requirement of cAMP elevation for this process. Our findings establish that synaptamide promotes axon growth while Shh antagonizes synaptamide-mediated cAMP elevation and axon growth by a SMO-independent, non-canonical pathway.

Growth of Limb Muscle is Dependent on Skeletal-Derived Indian Hedgehog

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Bren-Mattison, Yvette; Hausburg, Melissa; Olwin, Bradley B.

2011-01-01

During embryogenesis, muscle and bone develop in close temporal and spatial proximity. We show that Indian Hedgehog, a bone-derived signaling molecule, participates in growth of skeletal muscle. In Ihh−/− embryos, skeletal muscle development appears abnormal at embryonic day 14.5 and at later ages through embryonic day 20.5, dramatic losses of hindlimb muscle occur. To further examine the role of Ihh in myogenesis, we manipulated Ihh expression in the developing chick hindlimb. Reduction of Ihh in chicken embryo hindlimbs reduced skeletal muscle mass similar to that seen in Ihh−/− mouse embryos. The reduction in muscle mass appears to be a direct effect of Ihh since ectopic expression of Ihh by RCAS retroviral infection of chicken embryo hindlimbs restores muscle mass. These effects are independent of bone length, and occur when Shh is not expressed, suggesting Ihh acts directly on fetal myoblasts to regulate secondary myogenesis. Loss of muscle mass in Ihh null mouse embryos is accompanied by a dramatic increase in myoblast apoptosis accompanied by a loss of p21 protein. Our data suggest that Ihh promotes fetal myoblast survival during their differentiation into secondary myofibers by maintaining p21 protein levels. PMID:21683695

Lecithin-cholesterol acyltransferase in brain: Does oxidative stress influence the 24-hydroxycholesterol esterification?

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La Marca, Valeria; Maresca, Bernardetta; Spagnuolo, Maria Stefania; Cigliano, Luisa; Dal Piaz, Fabrizio; Di Iorio, Giuseppe; Abrescia, Paolo

2016-04-01

24-Hydroxycholesterol (24OH-C) is esterified by the enzyme lecithin-cholesterol acyltransferase (LCAT) in the cerebrospinal fluid (CSF). We report here that the level of 24OH-C esters was lower in CSF of patients with amyotrophic lateral sclerosis than in healthy subjects (54% vs 68% of total 24OH-C, p=0.0005; n=8). Similarly, the level of 24OH-C esters in plasma was lower in patients than in controls (62% vs 77% of total 24OH-C; p=0.0076). The enzyme amount in CSF, as measured by densitometry of the protein band revealed by immunoblotting, was about 4-fold higher in patients than in controls (p=0.0085). As differences in the concentration of the LCAT stimulator Apolipoprotein E were not found, we hypothesized that the reduced 24OH-C esterification in CSF of patients might depend on oxidative stress. We actually found that oxidative stress reduced LCAT activity in vitro, and 24OH-C effectively stimulated the enzyme secretion from astrocytoma cells in culture. Enhanced LCAT secretion from astrocytes might represent an adaptive response to the increase of non-esterified 24OH-C percentage, aimed to avoid the accumulation of this neurotoxic compound. The low degree of 24OH-C esterification in CSF or plasma might reflect reduced activity of LCAT during neurodegeneration. Copyright © 2015 Elsevier Ireland Ltd and the Japan Neuroscience Society. All rights reserved.

Histone acetyltransferase PCAF is required for Hedgehog-Gli-dependent transcription and cancer cell proliferation

DEFF Research Database (Denmark)

Malatesta, Martina; Steinhauer, Cornelia; Mohammad, Faizaan

2013-01-01

The Hedgehog (Hh) signaling pathway plays an important role in embryonic patterning and development of many tissues and organs as well as in maintaining and repairing mature tissues in adults. Uncontrolled activation of the Hh-Gli pathway has been implicated in developmental abnormalities as well...... that the histone acetyltransferase PCAF/KAT2B is an important factor of the Hh pathway. Specifically, we show that PCAF depletion impairs Hh activity and reduces expression of Hh target genes. Consequently, PCAF downregulation in medulloblastoma and glioblastoma cells leads to decreased proliferation and increased...... apoptosis. In addition, we found that PCAF interacts with GLI1, the downstream effector in the Hh-Gli pathway, and that PCAF or GLI1 loss reduces the levels of H3K9 acetylation on Hh target gene promoters. Finally, we observed that PCAF silencing reduces the tumor-forming potential of neural stem cells...

A Class of Diacylglycerol Acyltransferase 1 Inhibitors Identified by a Combination of Phenotypic High-throughput Screening, Genomics, and Genetics

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Kirsten Tschapalda

2016-06-01

Full Text Available Excess lipid storage is an epidemic problem in human populations. Thus, the identification of small molecules to treat or prevent lipid storage-related metabolic complications is of great interest. Here we screened >320.000 compounds for their ability to prevent a cellular lipid accumulation phenotype. We used fly cells because the multifarious tools available for this organism should facilitate unraveling the mechanism-of-action of active small molecules. Of the several hundred lipid storage inhibitors identified in the primary screen we concentrated on three structurally diverse and potent compound classes active in cells of multiple species (including human and negligible cytotoxicity. Together with Drosophila in vivo epistasis experiments, RNA-Seq expression profiles suggested that the target of one of the small molecules was diacylglycerol acyltransferase 1 (DGAT1, a key enzyme in the production of triacylglycerols and prominent human drug target. We confirmed this prediction by biochemical and enzymatic activity tests.

Beta2-adrenergic activity modulates vascular tone regulation in lecithin:cholesterol acyltransferase knockout mice

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Manzini, S.; Pinna, C.; Busnelli, M.; Cinquanta, P.; Rigamonti, E.; Ganzetti, G.S.; Dellera, F.; Sala, A.; Calabresi, L.; Franceschini, G.; Parolini, C.; Chiesa, G.

2015-01-01

Lecithin:cholesterol acyltransferase (LCAT) deficiency is associated with hypoalphalipoproteinemia, generally a predisposing factor for premature coronary heart disease. The evidence of accelerated atherosclerosis in LCAT-deficient subjects is however controversial. In this study, the effect of LCAT deficiency on vascular tone and endothelial function was investigated in LCAT knockout mice, which reproduce the human lipoprotein phenotype. Aortas from wild-type (Lcatwt) and LCAT knockout (LcatKO) mice exposed to noradrenaline showed reduced contractility in LcatKO mice (P < 0.005), whereas acetylcholine exposure showed a lower NO-dependent relaxation in LcatKO mice (P < 0.05). Quantitative PCR and Western blotting analyses suggested an adequate eNOS expression in LcatKO mouse aortas. Real-time PCR analysis indicated increased expression of β2-adrenergic receptors vs wild-type mice. Aorta stimulation with noradrenaline in the presence of propranolol, to abolish the β-mediated relaxation, showed the same contractile response in the two mouse lines. Furthermore, propranolol pretreatment of mouse aortas exposed to L-NAME prevented the difference in responses between Lcatwt and LcatKO mice. The results indicate that LCAT deficiency leads to increased β2-adrenergic relaxation and to a consequently decreased NO-mediated vasodilation that can be reversed to guarantee a correct vascular tone. The present study suggests that LCAT deficiency is not associated with an impaired vascular reactivity. PMID:26254103

Beta2-adrenergic activity modulates vascular tone regulation in lecithin:cholesterol acyltransferase knockout mice.

Science.gov (United States)

Manzini, S; Pinna, C; Busnelli, M; Cinquanta, P; Rigamonti, E; Ganzetti, G S; Dellera, F; Sala, A; Calabresi, L; Franceschini, G; Parolini, C; Chiesa, G

2015-11-01

Lecithin:cholesterol acyltransferase (LCAT) deficiency is associated with hypoalphalipoproteinemia, generally a predisposing factor for premature coronary heart disease. The evidence of accelerated atherosclerosis in LCAT-deficient subjects is however controversial. In this study, the effect of LCAT deficiency on vascular tone and endothelial function was investigated in LCAT knockout mice, which reproduce the human lipoprotein phenotype. Aortas from wild-type (Lcat(wt)) and LCAT knockout (Lcat(KO)) mice exposed to noradrenaline showed reduced contractility in Lcat(KO) mice (P<0.005), whereas acetylcholine exposure showed a lower NO-dependent relaxation in Lcat(KO) mice (P<0.05). Quantitative PCR and Western blotting analyses suggested an adequate eNOS expression in Lcat(KO) mouse aortas. Real-time PCR analysis indicated increased expression of β2-adrenergic receptors vs wild-type mice. Aorta stimulation with noradrenaline in the presence of propranolol, to abolish the β-mediated relaxation, showed the same contractile response in the two mouse lines. Furthermore, propranolol pretreatment of mouse aortas exposed to L-NAME prevented the difference in responses between Lcat(wt) and Lcat(KO) mice. The results indicate that LCAT deficiency leads to increased β2-adrenergic relaxation and to a consequently decreased NO-mediated vasodilation that can be reversed to guarantee a correct vascular tone. The present study suggests that LCAT deficiency is not associated with an impaired vascular reactivity. Copyright © 2015. Published by Elsevier Inc.

Endogenous ghrelin-O-acyltransferase (GOAT) acylates local ghrelin in the hippocampus.

Science.gov (United States)

Murtuza, Mohammad I; Isokawa, Masako

2018-01-01

Ghrelin is an appetite-stimulating peptide. Serine 3 on ghrelin must be acylated by octanoate via the enzyme ghrelin-O-acyltransferase (GOAT) for the peptide to bind and activate the cognate receptor, growth hormone secretagogue receptor type 1a (GHSR1a). Interest in GHSR1a increased dramatically when GHSR1a mRNA was demonstrated to be widespread in the brain, including the cortex and hippocampus, indicating that it has multifaceted functions beyond the regulation of metabolism. However, the source of octanoylated ghrelin for GHSR1a in the brain, outside of the hypothalamus, is not well understood. Here, we report the presence of GOAT and its ability to acylate non-octanoylated ghrelin in the hippocampus. GOAT immunoreactivity is aggregated at the base of the dentate granule cell layer in the rat and wild-type mouse. This immunoreactivity was not affected by the pharmacological inhibition of GHSR1a or the metabolic state-dependent fluctuation of systemic ghrelin levels. However, it was absent in the GHSR1a knockout mouse hippocampus, pointing the possibility that the expression of GHSR1a may be a prerequisite for the production of GOAT. Application of fluorescein isothiocyanate (FITC)-conjugated non-octanoylated ghrelin in live hippocampal slice culture (but not in fixed culture or in the presence of GOAT inhibitors) mimicked the binding profile of FITC-conjugated octanoylated ghrelin, suggesting that extracellularly applied non-octanoylated ghrelin was acylated by endogenous GOAT in the live hippocampus while GOAT being mobilized out of neurons. Our results will advance the understanding for the role of endogenous GOAT in the hippocampus and facilitate the search for the source of ghrelin that is intrinsic to the brain. © 2017 International Society for Neurochemistry.

Simplified procedure for the in vitro assay of the initial linear rate of the reaction of lecithin-cholesterol acyltransferase in human serum

International Nuclear Information System (INIS)

Mahadevan, V.; Soloff, L.A.

1985-01-01

A simple sensitive method for the determination of the initial rate of the reaction of lecithin-cholesterol acyltransferase by equilibrating [ 3 H]cholesterol with unesterified cholesterol of human serum is described. The resulting serum is incubated for various time periods at 37 degrees C and the increase of the label in the cholesterol ester fraction is measured. The labeling is effected by a fids at 37 degrees C and the increase of the label in the cholesterol ester fraction is measured. The labeling is effected by a filter paper method in which a paper strip containing the labeled cholesterol is placed in serum at 4 degrees C, thereby preventing the formation of labeled cholesterol esters by the action of the enzyme. The rate of the reaction was linear up to 30 min

Ontogenetic expression of Sonic Hedgehog in the chicken subpallium

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Sylvia M Bardet

2010-07-01

Full Text Available Sonic hedgehog (SHH is a secreted signaling factor that is implicated in the molecular patterning of the central nervous system (CNS, somites and limbs in vertebrates. SHH has a crucial role in the generation of ventral cell types along the entire rostrocaudal axis of the neural tube. It is secreted early in development by the axial mesoderm (prechordal plate and notochord and the overlying ventral neural tube. Recent studies clarified the impact of SHH signaling mechanisms on dorsoventral patterning of the spinal cord, but the corresponding phenomena in the rostral forebrain are slightly different and more complex. This notably involves separate Shh expression in the preoptic part of the forebrain alar plate, as well as in the hypothalamic floor and basal plates. The present work includes a detailed spatio-temporal description of the singular alar Shh expression pattern in the rostral preoptic forebrain of chick embryos, comparing it with FoxG1, Dlx5, Nkx2.1 and Nkx2.2 mRNA expression at diverse stages of development. As a result of this mapping, we report a subdivision of the preoptic region in dorsal and ventral zones; only the dorsal part shows Shh expression. The positive area impinges as well upon a median septocommissural preoptic domain. Our study strongly suggests tangential migration of Shh positive cells from the preoptic region into other subpallial domains, particularly into the pallidal mantle and the intermediate septum.

The subrhinal paleocortex in the hedgehog tenrec: a multiarchitectonic characterization and an analysis of its connections with the olfactory bulb.

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Künzle, H; Radtke-Schuller, S

2000-12-01

In the Madagascan hedgehog tenrec, Echinops telfairi, the entire paleocortical region (PCx) subjacent to the rhinal indentation is composed of three layers and occupies up to two thirds of the lateral hemisphere. A clear differentiation of PCx into its presumed constituents, the piriform cortex and the entorhinal cortex, as seen in other mammals, has not been obtained so far. To gain insight into location and intrinsic organization of these areas in a basal placental mammal we investigated the tenrec's PCx using cyto-, myelo- and chemoarchitectural criteria (zinc, acetylcholinesterase, NADPh-diaphorase, Wisteria floribunda agglutinin, parvalbumin, calbindin, calretinin) and analysed its connections with the olfactory bulb. The layers 2 and 3 of the tenrec's PCx differed from the corresponding layers in the rat. The layer 2 showed a complex distribution of corticobulbar cells but could not be subdivided, in contrast to layer 3. Additional cell groups in the depth of PCx were tentatively compared with subdivisions of the endopiriform region. The architectural and connectional features varied clearly along the rostrocaudal and dorso-ventral extents of PCx and gave hints for the presence of different paleocortical subdivisions. With the possible exception of an area located at the most caudal tip of the dorsomedial hemisphere, however, no conclusive evidence was obtained for the presence of a multilayered, entorhinal region. The bulbar projections to the PCx were very extensive and almost exclusively ipsilateral. The laterality of the projection is similar to that in higher mammals, but differs from that in the erinaceous hedgehog.

The role of the sonic hedgehog signalling pathway in patients with midline defects and congenital hypopituitarism.

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Gregory, L C; Gaston-Massuet, C; Andoniadou, C L; Carreno, G; Webb, E A; Kelberman, D; McCabe, M J; Panagiotakopoulos, L; Saldanha, J W; Spoudeas, H A; Torpiano, J; Rossi, M; Raine, J; Canham, N; Martinez-Barbera, J P; Dattani, M T

2015-05-01

The Gli family of zinc finger (GLI) transcription factors mediates the sonic hedgehog signalling pathway (HH) essential for CNS, early pituitary and ventral forebrain development in mice. Human mutations in this pathway have been described in patients with holoprosencephaly (HPE), isolated congenital hypopituitarism (CH) and cranial/midline facial abnormalities. Mutations in Sonic hedgehog (SHH) have been associated with HPE but not CH, despite murine studies indicating involvement in pituitary development. We aimed to establish the role of the HH pathway in the aetiology of hypothalamo-pituitary disorders by screening our cohort of patients with midline defects and/or CH for mutations in SHH, GLI2, Shh brain enhancer 2 (SBE2) and growth-arrest specific 1 (GAS1). Two variants and a deletion of GLI2 were identified in three patients. A novel variant at a highly conserved residue in the zinc finger DNA-binding domain, c.1552G > A [pE518K], was identified in a patient with growth hormone deficiency and low normal free T4. A nonsynonymous variant, c.2159G > A [p.R720H], was identified in a patient with a short neck, cleft palate and hypogonadotrophic hypogonadism. A 26·6 Mb deletion, 2q12·3-q21·3, encompassing GLI2 and 77 other genes, was identified in a patient with short stature and impaired growth. Human embryonic expression studies and molecular characterisation of the GLI2 mutant p.E518K support the potential pathogenicity of GLI2 mutations. No mutations were identified in GAS1 or SBE2. A novel SHH variant, c.1295T>A [p.I432N], was identified in two siblings with variable midline defects but normal pituitary function. Our data suggest that mutations in SHH, GAS1 and SBE2 are not associated with hypopituitarism, although GLI2 is an important candidate for CH. © 2014 John Wiley & Sons Ltd.

Stromal progesterone receptors mediate induction of Indian Hedgehog (IHH) in uterine epithelium and its downstream targets in uterine stroma.

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Simon, Liz; Spiewak, Kerry A; Ekman, Gail C; Kim, Jaeyeon; Lydon, John P; Bagchi, Milan K; Bagchi, Indrani C; DeMayo, Francesco J; Cooke, Paul S

2009-08-01

Uterine receptivity to embryo implantation depends on appropriate progesterone (P4) and estrogen stimulation. P4 rapidly stimulates production of the morphogen Indian hedgehog (IHH) in murine uterine epithelium as well as downstream molecules in the hedgehog pathway such as Patched homolog 1 (PTCH1) and nuclear receptor subfamily 2, group F, member 2 (NR2F2) in uterine stroma. Studies using IHH-null mice indicate that IHH is obligatory for the normal P4 response in the uterus. To determine whether IHH induction in uterine epithelium is mediated through P4 receptor (PR) in epithelium (E) and/or stroma (S), we produced tissue recombinants using uteri from neonatal PR knockout (ko) mice and wild-type (wt) mice containing PR in S and/or E or lacking PR altogether using a tissue recombinant methodology and assessed their response to P4. In tissue recombinants containing wt-S (wt-S + wt-E and wt-S + ko-E), P4 induced Ihh mRNA expression at 6 h that was 6-fold greater than in oil-treated controls (P Ihh mRNA expression was unaffected by P4 in ko-S + ko-E and ko-S + wt-E grafts despite epithelial PR expression in the latter. Nr2f2 and Ptch1 mRNA expression was similar in that it was stimulated by P4 only in recombinants containing stromal PR. These results indicate that stromal PR is both necessary and sufficient for P4 stimulation of epithelial IHH as well as downstream events such as PTCH1 and NR2F2 increases in stroma.

Hedgehog signaling in tumor cells facilitates osteoblast-enhanced osteolytic metastases.

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Shamik Das

Full Text Available The remodeling process in bone yields numerous cytokines and chemokines that mediate crosstalk between osteoblasts and osteoclasts and also serve to attract and support metastatic tumor cells. The metastatic tumor cells disturb the equilibrium in bone that manifests as skeletal complications. The Hedgehog (Hh pathway plays an important role in skeletogenesis. We hypothesized that the Hh pathway mediates an interaction between tumor cells and osteoblasts and influences osteoblast differentiation in response to tumor cells. We have determined that breast tumor cells have an activated Hh pathway characterized by upregulation of the ligand, IHH and transcription factor GLI1. Breast cancer cells interact with osteoblasts and cause an enhanced differentiation of pre-osteoblasts to osteoblasts that express increased levels of the osteoclastogenesis factors, RANKL and PTHrP. There is sustained expression of osteoclast-promoting factors, RANKL and PTHrP, even after the osteoblast differentiation ceases and apoptosis sets in. Moreover, tumor cells that are deficient in Hh signaling are compromised in their ability to induce osteoblast differentiation and consequently are inefficient in causing osteolysis. The stimulation of osteoblast differentiation sets the stage for osteoclast differentiation and overall promotes osteolysis. Thus, in the process of developing newer therapeutic strategies against breast cancer metastasis to bone it would worthwhile to keep in mind the role of the Hh pathway in osteoblast differentiation in an otherwise predominant osteolytic phenomenon.

The Impact of Hedgehog Signaling Pathway on DNA Repair Mechanisms in Human Cancer

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Meng, Erhong; Hanna, Ann; Samant, Rajeev S.; Shevde, Lalita A.

2015-01-01

Defined cellular mechanisms have evolved that recognize and repair DNA to protect the integrity of its structure and sequence when encountering assaults from endogenous and exogenous sources. There are five major DNA repair pathways: mismatch repair, nucleotide excision repair, direct repair, base excision repair and DNA double strand break repair (including non-homologous end joining and homologous recombination repair). Aberrant activation of the Hedgehog (Hh) signaling pathway is a feature of many cancer types. The Hh pathway has been documented to be indispensable for epithelial-mesenchymal transition, invasion and metastasis, cancer stemness, and chemoresistance. The functional transcription activators of the Hh pathway include the GLI proteins. Inhibition of the activity of GLI can interfere with almost all DNA repair types in human cancer, indicating that Hh/GLI functions may play an important role in enabling tumor cells to survive lethal types of DNA damage induced by chemotherapy and radiotherapy. Thus, Hh signaling presents an important therapeutic target to overcome DNA repair-enabled multi-drug resistance and consequently increase chemotherapeutic response in the treatment of cancer

The Impact of Hedgehog Signaling Pathway on DNA Repair Mechanisms in Human Cancer

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Meng, Erhong; Hanna, Ann; Samant, Rajeev S.; Shevde, Lalita A., E-mail: lsamant@uab.edu [Department of Pathology, Comprehensive Cancer Center, University of Alabama at Birmingham, WTI320D, 1824 6th Avenue South, Birmingham, AL 35233 (United States)

2015-07-21

Defined cellular mechanisms have evolved that recognize and repair DNA to protect the integrity of its structure and sequence when encountering assaults from endogenous and exogenous sources. There are five major DNA repair pathways: mismatch repair, nucleotide excision repair, direct repair, base excision repair and DNA double strand break repair (including non-homologous end joining and homologous recombination repair). Aberrant activation of the Hedgehog (Hh) signaling pathway is a feature of many cancer types. The Hh pathway has been documented to be indispensable for epithelial-mesenchymal transition, invasion and metastasis, cancer stemness, and chemoresistance. The functional transcription activators of the Hh pathway include the GLI proteins. Inhibition of the activity of GLI can interfere with almost all DNA repair types in human cancer, indicating that Hh/GLI functions may play an important role in enabling tumor cells to survive lethal types of DNA damage induced by chemotherapy and radiotherapy. Thus, Hh signaling presents an important therapeutic target to overcome DNA repair-enabled multi-drug resistance and consequently increase chemotherapeutic response in the treatment of cancer.

The Ketogenic Diet Does Not Affect Growth of Hedgehog Pathway Medulloblastoma in Mice

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Dang, Mai T.; Wehrli, Suzanne; Dang, Chi V.; Curran, Tom

2015-01-01

The altered metabolism of cancer cells has long been viewed as a potential target for therapeutic intervention. In particular, brain tumors often display heightened glycolysis, even in the presence of oxygen. A subset of medulloblastoma, the most prevalent malignant brain tumor in children, arises as a consequence of activating mutations in the Hedgehog (HH) pathway, which has been shown to promote aerobic glycolysis. Therefore, we hypothesized that a low carbohydrate, high fat ketogenic diet would suppress tumor growth in a genetically engineered mouse model of medulloblastoma. However, we found that the ketogenic diet did not slow the growth of spontaneous tumors or allograft flank tumors, and it did not exhibit synergy with a small molecule inhibitor of Smoothened. Serum insulin was significantly reduced in mice fed the ketogenic diet, but no alteration in PI3 kinase activity was observed. These findings indicate that while the ketogenic diet may be effective in inhibiting growth of other tumor types, it does not slow the growth of HH-medulloblastoma in mice. PMID:26192445

The Ketogenic Diet Does Not Affect Growth of Hedgehog Pathway Medulloblastoma in Mice.

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Mai T Dang

Full Text Available The altered metabolism of cancer cells has long been viewed as a potential target for therapeutic intervention. In particular, brain tumors often display heightened glycolysis, even in the presence of oxygen. A subset of medulloblastoma, the most prevalent malignant brain tumor in children, arises as a consequence of activating mutations in the Hedgehog (HH pathway, which has been shown to promote aerobic glycolysis. Therefore, we hypothesized that a low carbohydrate, high fat ketogenic diet would suppress tumor growth in a genetically engineered mouse model of medulloblastoma. However, we found that the ketogenic diet did not slow the growth of spontaneous tumors or allograft flank tumors, and it did not exhibit synergy with a small molecule inhibitor of Smoothened. Serum insulin was significantly reduced in mice fed the ketogenic diet, but no alteration in PI3 kinase activity was observed. These findings indicate that while the ketogenic diet may be effective in inhibiting growth of other tumor types, it does not slow the growth of HH-medulloblastoma in mice.

Hedgehog Signaling Regulates Epithelial-Mesenchymal Transition in Pancreatic Cancer Stem-Like Cells

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Wang, Feng; Ma, Ling; Zhang, Zhengkui; Liu, Xiaoran; Gao, Hongqiao; Zhuang, Yan; Yang, Pei; Kornmann, Marko; Tian, Xiaodong; Yang, Yinmo

2016-01-01

Hedgehog (Hh) signaling is crucially involved in tumorigenesis. This study aimed to assess the role of Hh signaling in the regulation of epithelial-mesenchymal transition (EMT), stemness properties and chemoresistance of human pancreatic Panc-1 cancer stem cells (CSCs). Panc-1 cells were transfected with recombinant lentiviral vectors to silence SMO and serum-free floating-culture system was used to isolate Panc-1 tumorspheres. The expression of CSC and EMT markers was detected by flow cytometry, real-time RT-PCR and Western blot analysis. Malignant behaviors of Panc-1 CSC were evaluated by tumorigenicity assays and nude mouse lung metastasis model. We found that tumorspheres derived from pancreatic cancer cell line Panc-1 possessed self-renewal, differentiation and stemness properties. Hh pathway and EMT were active in Panc-1 tumorspheres. Inhibition of Hh signaling by SMO knockdown inhibited self-renewal, EMT, invasion, chemoresistance, pulmonary metastasis, tumorigenesis of pancreatic CSCs. In conclusion, Hh signaling contributes to the maintenance of stem-like properties and chemoresistance of pancreatic CSC and promotes the tumorigenesis and metastasis of pancreatic cancer. Hh pathway is a potential molecular target for the development of therapeutic strategies for pancreatic CSCs. PMID:26918054

The role of lecithin cholesterol acyltransferase and organic substances from coal in the etiology of Balkan endemic nephropathy: A new hypothesis

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Pavlovic, N.M.; Orem, W.H.; Tatu, C.A.; Lerch, H.E.; Bunnell, J.E.; Feder, G.L.; Kostic, E.N.; Ordodi, V.L.

2008-01-01

Balkan endemic nephropathy (BEN) occurs in Serbia, Bulgaria, Romania, Bosnia and Herzegovina, and Croatia. BEN has been characterized as a chronic, slowly progressive renal disease of unknown etiology. In this study, we examined the influence of soluble organic compounds in drinking water leached from Pliocene lignite from BEN-endemic areas on plasma lecithin-cholesterol acyltransferase (LCAT) activity. We found that changes for all samples were the most prominent for the dilution category containing 90% plasma and 10% of diluting media. Water samples from BEN villages from Serbia and Romania showed higher LCAT inhibiting activity (p = 0.02) and (p = 0.003), respectively, compared to deionised water and non-endemic water. A secondary LCAT deficiency could result from this inhibitory effect of the organic compounds found in endemic water supplies and provide an ethiopathogenic basis for the development of BEN in the susceptible population. ?? 2007 Elsevier Ltd. All rights reserved.

Discovery of a potent and orally available acyl-CoA: cholesterol acyltransferase inhibitor as an anti-atherosclerotic agent: (4-phenylcoumarin)acetanilide derivatives.

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Ogino, Masaki; Fukui, Seiji; Nakada, Yoshihisa; Tokunoh, Ryosuke; Itokawa, Shigekazu; Kakoi, Yuichi; Nishimura, Satoshi; Sanada, Tsukasa; Fuse, Hiromitsu; Kubo, Kazuki; Wada, Takeo; Marui, Shogo

2011-01-01

Acyl-CoA: cholesterol acyltransferase (ACAT) is an intracellular enzyme that catalyzes cholesterol esterification. ACAT inhibitors are expected to be potent therapeutic agents for the treatment of atherosclerosis. A series of potent ACAT inhibitors based on an (4-phenylcoumarin)acetanilide scaffold was identified. Evaluation of the structure-activity relationships of a substituent on this scaffold, with an emphasis on improving the pharmacokinetic profile led to the discovery of 2-[7-chloro-4-(3-chlorophenyl)-6-methyl-2-oxo-2H-chromen-3-yl]-N-[4-chloro-2-(trifluoromethyl)phenyl]acetamide (23), which exhibited potent ACAT inhibitory activity (IC50=12 nM) and good pharmacokinetic profile in mice. Compound 23 also showed regressive effects on atherosclerotic plaques in apolipoprotein (apo)E knock out (KO) mice at a dose of 0.3 mg/kg per os (p.o.).

The regulation of tooth morphogenesis is associated with epithelial cell proliferation and the expression of Sonic hedgehog through epithelial-mesenchymal interactions

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Ishida, Kentaro; Murofushi, Mayumi; Nakao, Kazuhisa; Morita, Ritsuko; Ogawa, Miho; Tsuji, Takashi

2011-01-01

Research highlights: → Bioengineered teeth regulated the contact area of epithelium and mesenchyme. → The crown width is regulated by the contact area of the epithelium and mesenchyme. → This regulation is associated with cell proliferation and Sonic hedgehog expression. → The cusp number is correlated with the crown width of the bioengineered tooth. → Cell proliferation and Shh expression areas regulate the tooth morphogenesis. -- Abstract: Ectodermal organs, such as the tooth, salivary gland, hair, and mammary gland, develop through reciprocal epithelial-mesenchymal interactions. Tooth morphologies are defined by the crown width and tooth length (macro-morphologies), and by the number and locations of the cusp and roots (micro-morphologies). In our current study, we report that the crown width of a bioengineered molar tooth, which was reconstructed using dissociated epithelial and mesenchymal cells via an organ germ method, can be regulated by the contact area between epithelial and mesenchymal cell layers. We further show that this is associated with cell proliferation and Sonic hedgehog (Shh) expression in the inner enamel epithelium after the germ stage has formed a secondary enamel knot. We also demonstrate that the cusp number is significantly correlated with the crown width of the bioengineered tooth. These findings suggest that the tooth micro-morphology, i.e. the cusp formation, is regulated after the tooth width, or macro-morphology, is determined. These findings also suggest that the spatiotemporal patterning of cell proliferation and the Shh expression areas in the epithelium regulate the crown width and cusp formation of the developing tooth.

Exome sequencing identifies three novel candidate genes implicated in intellectual disability.

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Zehra Agha

Full Text Available Intellectual disability (ID is a major health problem mostly with an unknown etiology. Recently exome sequencing of individuals with ID identified novel genes implicated in the disease. Therefore the purpose of the present study was to identify the genetic cause of ID in one syndromic and two non-syndromic Pakistani families. Whole exome of three ID probands was sequenced. Missense variations in two plausible novel genes implicated in autosomal recessive ID were identified: lysine (K-specific methyltransferase 2B (KMT2B, zinc finger protein 589 (ZNF589, as well as hedgehog acyltransferase (HHAT with a de novo mutation with autosomal dominant mode of inheritance. The KMT2B recessive variant is the first report of recessive Kleefstra syndrome-like phenotype. Identification of plausible causative mutations for two recessive and a dominant type of ID, in genes not previously implicated in disease, underscores the large genetic heterogeneity of ID. These results also support the viewpoint that large number of ID genes converge on limited number of common networks i.e. ZNF589 belongs to KRAB-domain zinc-finger proteins previously implicated in ID, HHAT is predicted to affect sonic hedgehog, which is involved in several disorders with ID, KMT2B associated with syndromic ID fits the epigenetic module underlying the Kleefstra syndromic spectrum. The association of these novel genes in three different Pakistani ID families highlights the importance of screening these genes in more families with similar phenotypes from different populations to confirm the involvement of these genes in pathogenesis of ID.

Acute sterol o-acyltransferase 2 (SOAT2 knockdown rapidly mobilizes hepatic cholesterol for fecal excretion.

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Stephanie M Marshall

Full Text Available The primary risk factor for atherosclerotic cardiovascular disease is LDL cholesterol, which can be reduced by increasing cholesterol excretion from the body. Fecal cholesterol excretion can be driven by a hepatobiliary as well as a non-biliary pathway known as transintestinal cholesterol efflux (TICE. We previously showed that chronic knockdown of the hepatic cholesterol esterifying enzyme sterol O-acyltransferase 2 (SOAT2 increased fecal cholesterol loss via TICE. To elucidate the initial events that stimulate TICE, C57Bl/6 mice were fed a high cholesterol diet to induce hepatic cholesterol accumulation and were then treated for 1 or 2 weeks with an antisense oligonucleotide targeting SOAT2. Within 2 weeks of hepatic SOAT2 knockdown (SOAT2HKD, the concentration of cholesteryl ester in the liver was reduced by 70% without a reciprocal increase in hepatic free cholesterol. The rapid mobilization of hepatic cholesterol stores resulted in a ∼ 2-fold increase in fecal neutral sterol loss but no change in biliary cholesterol concentration. Acute SOAT2HKD increased plasma cholesterol carried primarily in lipoproteins enriched in apoB and apoE. Collectively, our data suggest that acutely reducing SOAT2 causes hepatic cholesterol to be swiftly mobilized and packaged onto nascent lipoproteins that feed cholesterol into the TICE pathway for fecal excretion.

The Hedgehog Signalling Pathway in Cell Migration and Guidance: What We Have Learned from Drosophila melanogaster

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Sofia J. Araújo

2015-10-01

Full Text Available Cell migration and guidance are complex processes required for morphogenesis, the formation of tumor metastases, and the progression of human cancer. During migration, guidance molecules induce cell directionality and movement through complex intracellular mechanisms. Expression of these molecules has to be tightly regulated and their signals properly interpreted by the receiving cells so as to ensure correct navigation. This molecular control is fundamental for both normal morphogenesis and human disease. The Hedgehog (Hh signaling pathway is evolutionarily conserved and known to be crucial for normal cellular growth and differentiation throughout the animal kingdom. The relevance of Hh signaling for human disease is emphasized by its activation in many cancers. Here, I review the current knowledge regarding the involvement of the Hh pathway in cell migration and guidance during Drosophila development and discuss its implications for human cancer origin and progression.

Analysis of testosterone effects on sonic hedgehog signaling in juvenile, adolescent and adult sprague dawley rat penis.

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Bond, Christopher W; Angeloni, Nicholas L; Podlasek, Carol A

2010-03-01

Smooth muscle apoptosis is a major contributing factor to erectile dysfunction (ED) development in prostatectomy and diabetic patients and animal models. A critical regulator of penile smooth muscle and apoptosis is Sonic hedgehog (SHH). The SHH protein is decreased in ED models and SHH treatment of cavernous nerve (CN) injured rats prevents smooth muscle apoptosis. A close association between androgen deficiency and ED has been suggested in the literature, but few studies have examined the molecular effects on penile smooth muscle and on known signaling mechanisms that regulate morphology. Aim. Examine testosterone and SHH interaction in eugonadal adult, adolescent and juvenile rats by performing castration studies and treatment with supraphysiological testosterone. The eugonadal adult Sprague Dawley rats were either treated with testosterone for 7 or 14 days (N = 14) or were castrated for 4 or 7 days (N = 12). The juvenile rats were treated with testosterone for 8 days (N = 7). The adolescent rats were castrated and sacrificed at P88 (N = 8). The control rats had empty vehicle (N = 22) or sham surgery (N = 20). The active form of SHH protein and mRNA were quantified by semi-quantitative immunohistochemical analysis and real-time reverse transcriptase polymerase chain reaction (RT-PCR). Testosterone treatment did not alter SHH signaling in juvenile rats. Shh mRNA increased 3.2-fold and SHH protein increased 1.2-fold in rats castrated during puberty. In adult rats, castration decreased Shh mRNA 3.2-fold but did not alter SHH protein. Testosterone supplement in adult rats increased Shh mRNA 2.3-fold and decreased SHH protein 1.3-fold. SHH signaling is independent of testosterone in normal juvenile rats and is sensitive to testosterone during adolescence, while testosterone supplement in the adult adversely impacts SHH signaling in a very similar manner to that observed with CN injury.

Lysophosphatidic acid acyltransferase β (LPAATβ promotes the tumor growth of human osteosarcoma.

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Farbod Rastegar

2010-12-01

Full Text Available Osteosarcoma is the most common primary malignancy of bone with poorly characterized molecular pathways important in its pathogenesis. Increasing evidence indicates that elevated lipid biosynthesis is a characteristic feature of cancer. We sought to investigate the role of lysophosphatidic acid acyltransferase β (LPAATβ, aka, AGPAT2 in regulating the proliferation and growth of human osteosarcoma cells. LPAATβ can generate phosphatidic acid, which plays a key role in lipid biosynthesis as well as in cell proliferation and survival. Although elevated expression of LPAATβ has been reported in several types of human tumors, the role of LPAATβ in osteosarcoma progression has yet to be elucidated.Endogenous expression of LPAATβ in osteosarcoma cell lines is analyzed by using semi-quantitative PCR and immunohistochemical staining. Adenovirus-mediated overexpression of LPAATβ and silencing LPAATβ expression is employed to determine the effect of LPAATβ on osteosarcoma cell proliferation and migration in vitro and osteosarcoma tumor growth in vivo. We have found that expression of LPAATβ is readily detected in 8 of the 10 analyzed human osteosarcoma lines. Exogenous expression of LPAATβ promotes osteosarcoma cell proliferation and migration, while silencing LPAATβ expression inhibits these cellular characteristics. We further demonstrate that exogenous expression of LPAATβ effectively promotes tumor growth, while knockdown of LPAATβ expression inhibits tumor growth in an orthotopic xenograft model of human osteosarcoma.Our results strongly suggest that LPAATβ expression may be associated with the aggressive phenotypes of human osteosarcoma and that LPAATβ may play an important role in regulating osteosarcoma cell proliferation and tumor growth. Thus, targeting LPAATβ may be exploited as a novel therapeutic strategy for the clinical management of osteosarcoma. This is especially attractive given the availability of selective

Sonic hedgehog signaling in spinal cord contributes to morphine-induced hyperalgesia and tolerance through upregulating brain-derived neurotrophic factor expression

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Song, Zhi-Jing; Miao, Shuai; Zhao, Ye; Wang, Xiu-Li; Liu, Yue-Peng

2018-01-01

Purpose Preventing opioid-induced hyperalgesia and tolerance continues to be a major clinical challenge, and the underlying mechanisms of hyperalgesia and tolerance remain elusive. Here, we investigated the role of sonic hedgehog (Shh) signaling in opioid-induced hyperalgesia and tolerance. Methods Shh signaling expression, behavioral changes, and neurochemical alterations induced by morphine were analyzed in male adult CD-1 mice with repeated administration of morphine. To investigate the contribution of Shh to morphine-induced hyperalgesia (MIH) and tolerance, Shh signaling inhibitor cyclopamine and Shh small interfering RNA (siRNA) were used. To explore the mechanisms of Shh signaling in MIH and tolerance, brain-derived neurotrophic factor (BDNF) inhibitor K252 and anti-BDNF antibody were used. Results Repeated administration of morphine produced obvious hyperalgesia and tolerance. The behavioral changes were correlated with the upregulation and activation of morphine treatment-induced Shh signaling. Pharmacologic and genetic inhibition of Shh signaling significantly delayed the generation of MIH and tolerance and associated neurochemical changes. Chronic morphine administration also induced upregulation of BDNF. Inhibiting BDNF effectively delayed the generation of MIH and tolerance. The upregulation of BDNF induced by morphine was significantly suppressed by inhibiting Shh signaling. In naïve mice, exogenous activation of Shh signaling caused a rapid increase of BDNF expression, as well as thermal hyperalgesia. Inhibiting BDNF significantly suppressed smoothened agonist-induced hyperalgesia. Conclusion These findings suggest that Shh signaling may be a critical mediator for MIH and tolerance by regulating BDNF expression. Inhibiting Shh signaling, especially during the early phase, may effectively delay or suppress MIH and tolerance. PMID:29662325

Sonic hedgehog signaling regulates actin cytoskeleton via Tiam1-Rac1 cascade during spine formation.

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Sasaki, Nobunari; Kurisu, Junko; Kengaku, Mineko

2010-12-01

The sonic hedgehog (Shh) pathway has essential roles in several processes during development of the vertebrate central nervous system (CNS). Here, we report that Shh regulates dendritic spine formation in hippocampal pyramidal neurons via a novel pathway that directly regulates the actin cytoskeleton. Shh signaling molecules Patched (Ptc) and Smoothened (Smo) are expressed in several types of postmitotic neurons, including cerebellar Purkinje cells and hippocampal pyramidal neurons. Knockdown of Smo induces dendritic spine formation in cultured hippocampal neurons independently of Gli-mediated transcriptional activity. Smo interacts with Tiam1, a guanine nucleotide exchange factor for Rac1, via its cytoplasmic C-terminal region. Inhibition of Tiam1 or Rac1 activity suppresses spine induction by Smo knockdown. Shh induces remodeling of the actin cytoskeleton independently of transcriptional activation in mouse embryonic fibroblasts. These findings demonstrate a novel Shh pathway that regulates the actin cytoskeleton via Tiam1-Rac1 activation. Copyright © 2010 Elsevier Inc. All rights reserved.

Gene expression analysis uncovers novel Hedgehog interacting protein (HHIP) effects in human bronchial epithelial cells

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Zhou, Xiaobo; Qiu, Weiliang; Sathirapongsasuti, J. Fah.; Cho, Michael H.; Mancini, John D.; Lao, Taotao; Thibault, Derek M.; Litonjua, Gus; Bakke, Per S.; Gulsvik, Amund; Lomas, David A.; Beaty, Terri H.; Hersh, Craig P.; Anderson, Christopher; Geigenmuller, Ute; Raby, Benjamin A.; Rennard, Stephen I.; Perrella, Mark A.; Choi, Augustine M.K.; Quackenbush, John; Silverman, Edwin K.

2013-01-01

Hedgehog Interacting Protein (HHIP) was implicated in chronic obstructive pulmonary disease (COPD) by genome-wide association studies (GWAS). However, it remains unclear how HHIP contributes to COPD pathogenesis. To identify genes regulated by HHIP, we performed gene expression microarray analysis in a human bronchial epithelial cell line (Beas-2B) stably infected with HHIP shRNAs. HHIP silencing led to differential expression of 296 genes; enrichment for variants nominally associated with COPD was found. Eighteen of the differentially expressed genes were validated by real-time PCR in Beas-2B cells. Seven of 11 validated genes tested in human COPD and control lung tissues demonstrated significant gene expression differences. Functional annotation indicated enrichment for extracellular matrix and cell growth genes. Network modeling demonstrated that the extracellular matrix and cell proliferation genes influenced by HHIP tended to be interconnected. Thus, we identified potential HHIP targets in human bronchial epithelial cells that may contribute to COPD pathogenesis. PMID:23459001

Accumulation of the Vitamin D Precursor Cholecalciferol Antagonizes Hedgehog Signaling to Impair Hemogenic Endothelium Formation

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Mauricio Cortes

2015-10-01

Full Text Available Hematopoietic stem and progenitor cells (HSPCs are born from hemogenic endothelium in the dorsal aorta. Specification of this hematopoietic niche is regulated by a signaling axis using Hedgehog (Hh and Notch, which culminates in expression of Runx1 in the ventral wall of the artery. Here, we demonstrate that the vitamin D precursor cholecalciferol (D3 modulates HSPC production by impairing hemogenic vascular niche formation. Accumulation of D3 through exogenous treatment or inhibition of Cyp2r1, the enzyme required for D3 25-hydroxylation, results in Hh pathway antagonism marked by loss of Gli-reporter activation, defects in vascular niche identity, and reduced HSPCs. Mechanistic studies indicated the effect was specific to D3, and not active 1,25-dihydroxy vitamin D3, acting on the extracellular sterol-binding domain of Smoothened. These findings highlight a direct impact of inefficient vitamin D synthesis on cell fate commitment and maturation in Hh-regulated tissues, which may have implications beyond hemogenic endothelium specification.

Composition and dosage of a multipartite enhancer cluster control developmental expression of Ihh (Indian hedgehog).

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Will, Anja J; Cova, Giulia; Osterwalder, Marco; Chan, Wing-Lee; Wittler, Lars; Brieske, Norbert; Heinrich, Verena; de Villartay, Jean-Pierre; Vingron, Martin; Klopocki, Eva; Visel, Axel; Lupiáñez, Darío G; Mundlos, Stefan

2017-10-01

Copy number variations (CNVs) often include noncoding sequences and putative enhancers, but how these rearrangements induce disease is poorly understood. Here we investigate CNVs involving the regulatory landscape of IHH (encoding Indian hedgehog), which cause multiple, highly localized phenotypes including craniosynostosis and synpolydactyly. We show through transgenic reporter and genome-editing studies in mice that Ihh is regulated by a constellation of at least nine enhancers with individual tissue specificities in the digit anlagen, growth plates, skull sutures and fingertips. Consecutive deletions, resulting in growth defects of the skull and long bones, showed that these enhancers function in an additive manner. Duplications, in contrast, caused not only dose-dependent upregulation but also misexpression of Ihh, leading to abnormal phalanges, fusion of sutures and syndactyly. Thus, precise spatiotemporal control of developmental gene expression is achieved by complex multipartite enhancer ensembles. Alterations in the composition of such clusters can result in gene misexpression and disease.

LECITHIN: CHOLESTEROL ACYLTRANSFERASE ACTIVITY IS DECREASED IN TYPE 2 DIABETES MELLITUS

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A. Ghanei

2007-09-01

Full Text Available Lecithin cholesterol acyltransferase (LCAT plays a major role in the removal of free cholesterol from tissues via assisting HDL-C maturation, and its activity has been proposed as the main indicator of HDL-C function. The aim of the study was to measure LCAT activity in type 2 diabetic patients and to elucidate whether LCAT is associated with metabolic control, and insulin resistance. A case-control study was conducted in Imam Khomeini Hospital during 2006, recruiting 45 type 2 diabetes mellitus patients and 45 healthy subjects. Cases and controls were matched regarding gender, age and body mass index (BMI. FBS, lipid profile, LCAT activity, HbA1C, insulin were measured and insulin resistance (HOMA-IRwas calculated for both patients and controls. The studied variables were then compared between the two groups, and the association of LCAT activity with any of the variables was examined. Twenty-five subjects were female and 20 male both among patients and controls. Mean age of diabetics was 49.9 yrs (range, 40-64, and of controls 51.1 yrs (range, 39-64. FBS, HbA1C, HOMA-IR and TG in patients were significantly higher than controls, and HDL-C in controls was significantly higher than patients. LCAT activity of patients (73 9.1 µmol/L/h was significantly lower than that in controls (88 4.5 µmol/L/h (p<0.001. LCAT activity had significant inverse correlations with HbA1C and duration of diabetes. After multilinear regression analysis in patients, LCAT activity was only correlated with HbA1C level (ß= -0.9, p<0.001. LCAT activity had no significant association with HDL-C and HOMA-IR in any of the groups."nLCAT activity is significantly decreased in patients with type 2 diabetes compared with healthy controls, and has an inverse correlation with the magnitude of hyperglycemia.

Molecular Cloning and Characterization of a Novel Human Glycine-N-acyltransferase Gene GLYATL1, Which Activates Transcriptional Activity of HSE Pathway

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Long Yu

2007-05-01

Full Text Available The glycine-N-acyltransferase (GLYAT is well known to be involved in thedetoxification of endogenous and exogenous xenobiotic acyl-CoA's in mammals.Unfortunately, the knowledge about the gene encoding GLYAT is very limited. Here wereport a novel gene encoding a GLYAT member, designated as GLYATL1, which was1546 base pairs in length and contained an open reading frame (ORF encoding apolypeptide of 302 amino acids. GLYATL1 was a split gene that was consisted of 7 exonsand 6 introns and mapped to chromosome 11q12.1. The expression of GLYATL1 could befound in liver, kidney, pancreas, testis, ovary and stomach among 18 human tissues by RT-PCR analysis. Subcellular localization of myc-tagged GLYATL1 fusion protein revealedthat GLYATL1 was distributed primarily in the cytoplasm of COS-7 cells. Furthermore,through the pathway profiling assay, the GLYATL1 protein was found to activate HSEsignaling pathway in a dose-dependent manner when overexpressed in HEK293T cells.

Induction of 1-acylglycerophosphocholine acyltransferase genes by fibrates in the liver of rats.

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Yamazaki, Tohru; Wakabayashi, Michiko; Ikeda, Erika; Tanaka, Shizuyo; Sakamoto, Takeshi; Mitsumoto, Atsushi; Kudo, Naomi; Kawashima, Yoichi

2012-01-01

The effect of fibrates (clofibric acid, bezafibrate and fenofibrate) on the gene expression and activity of 1-acylglycerophosphocholine acyltransferase (LPCAT) was investigated. The administration of 0.1% (w/w) clofibric acid, bezafibrate or fenofibrate in diet for 14 d to rats induced LPCAT activity in hepatic microsomes in the following order: fenofibrate>bezafibrate>clofibric acid. The LPCAT induced by fenofibrate preferred to arachidonoyl-CoA and linoleoyl-CoA to a greater extent than did LPCAT in control microsomes. The treatment with the fibrates resulted in upregulation of the relative expression of mRNAs encoding LPCAT3 and LPCAT4 in the following order: fenofibrate>bezafibrate>clofibric acid. The administration of fibrates did not change the expression of genes encoding either LPCAT1 or LPCAT2. The treatment with fibrates elevated relative levels of both mRNAs encoding Δ6 desaturase (Fads2) and Δ5 desaturase (Fads1) in the order of fenofibrate>bezafibrate>clofibric acid, and the extent of the increase in the level of Δ6 desaturase mRNA was greater than that of Δ5 desaturase. Fatty acid profile in hepatic phosphatidylcholine (PC) was significantly changed by the treatments with fibrates. These results suggest (i) that fibrates induce LPCAT activity in hepatic microsomes by elevating the expression of genes encoding LPCAT3 and LPCAT4, (ii) that the changes in fatty acid profile of hepatic PC are, in part, due to the elevated expression of two isoforms, LPCAT3 and LPCAT4, and (iii) that the ability of fibrates to induce these changes are in the order of fenofibrate>bezafibrate>clofibric acid.

Agonistic Human Antibodies Binding to Lecithin-Cholesterol Acyltransferase Modulate High Density Lipoprotein Metabolism*

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Gunawardane, Ruwanthi N.; Fordstrom, Preston; Piper, Derek E.; Masterman, Stephanie; Siu, Sophia; Liu, Dongming; Brown, Mike; Lu, Mei; Tang, Jie; Zhang, Richard; Cheng, Janet; Gates, Andrew; Meininger, David; Chan, Joyce; Carlson, Tim; Walker, Nigel; Schwarz, Margrit; Delaney, John; Zhou, Mingyue

2016-01-01

Drug discovery opportunities where loss-of-function alleles of a target gene link to a disease-relevant phenotype often require an agonism approach to up-regulate or re-establish the activity of the target gene. Antibody therapy is increasingly recognized as a favored drug modality due to multiple desirable pharmacological properties. However, agonistic antibodies that enhance the activities of the target enzymes are rarely developed because the discovery of agonistic antibodies remains elusive. Here we report an innovative scheme of discovery and characterization of human antibodies capable of binding to and agonizing a circulating enzyme lecithin cholesterol acyltransferase (LCAT). Utilizing a modified human LCAT protein with enhanced enzymatic activity as an immunogen, we generated fully human monoclonal antibodies using the XenoMouseTM platform. One of the resultant agonistic antibodies, 27C3, binds to and substantially enhances the activity of LCAT from humans and cynomolgus macaques. X-ray crystallographic analysis of the 2.45 Å LCAT-27C3 complex shows that 27C3 binding does not induce notable structural changes in LCAT. A single administration of 27C3 to cynomolgus monkeys led to a rapid increase of plasma LCAT enzymatic activity and a 35% increase of the high density lipoprotein cholesterol that was observed up to 32 days after 27C3 administration. Thus, this novel scheme of immunization in conjunction with high throughput screening may represent an effective strategy for discovering agonistic antibodies against other enzyme targets. 27C3 and other agonistic human anti-human LCAT monoclonal antibodies described herein hold potential for therapeutic development for the treatment of dyslipidemia and cardiovascular disease. PMID:26644477

In silico characterization of 1,2-diacylglycerol cholinephosphotransferase and lysophospha-tidylcholine acyltransferase genes in Glycine max L. Merrill.

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Sousa, C S; Barros, B A; Barh, D; Ghosh, P; Azevedo, V; Barros, E G; Moreira, M A

2016-08-26

The enzymes 1,2-diacylglycerol cholinephosphotrans-ferase (CPT) and lysophosphatidylcholine acyltransferase (LPCAT) are important in lipid metabolism in soybean seeds. Thus, understand-ing the genes that encode these enzymes may enable their modification and aid the improvement of soybean oil quality. In soybean, the genes encoding these enzymes have not been completely described; there-fore, this study aimed to identify, characterize, and analyze the in silico expression of these genes in soybean. We identified two gene models encoding CPT and two gene models encoding LPCAT, one of which presented an alternative transcript. The sequences were positioned on the physical map of soybean and the promoter regions were analyzed. Cis-elements responsible for seed-specific expression and responses to biotic and abiotic stresses were identified. Virtual expression analysis of the gene models for CPT and LPCAT indicated that these genes are expressed under different stress conditions, in somatic embryos during differentiation, in immature seeds, root tissues, and calli. Putative ami-no acid sequences revealed the presence of transmembrane domains, and analysis of the cellular localization of these enzymes revealed they are located in the endoplasmic reticulum.

Target of rapamycin (TOR) plays a critical role in triacylglycerol accumulation in microalgae.

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Imamura, Sousuke; Kawase, Yasuko; Kobayashi, Ikki; Sone, Toshiyuki; Era, Atsuko; Miyagishima, Shin-Ya; Shimojima, Mie; Ohta, Hiroyuki; Tanaka, Kan

2015-10-01

Most microalgae produce triacylglycerol (TAG) under stress conditions such as nitrogen depletion, but the underlying molecular mechanism remains unclear. In this study, we focused on the role of target of rapamycin (TOR) in TAG accumulation. TOR is a serine/threonine protein kinase that is highly conserved and plays pivotal roles in nitrogen and other signaling pathways in eukaryotes. We previously constructed a rapamycin-susceptible Cyanidioschyzon merolae, a unicellular red alga, by expressing yeast FKBP12 protein to evaluate the results of TOR inhibition (Imamura et al. in Biochem Biophys Res Commun 439:264-269, 2013). By using this strain, we here report that rapamycin-induced TOR inhibition results in accumulation of cytoplasmic lipid droplets containing TAG. Transcripts for TAG synthesis-related genes, such as glycerol-3-phosphate acyltransferase and acyl-CoA:diacylglycerol acyltransferase (DGAT), were increased by rapamycin treatment. We also found that fatty acid synthase-dependent de novo fatty acid synthesis was required for the accumulation of lipid droplets. Induction of TAG and up-regulation of DGAT gene expression by rapamycin were similarly observed in the unicellular green alga, Chlamydomonas reinhardtii. These results suggest the general involvement of TOR signaling in TAG accumulation in divergent microalgae.

Reprogramming Medulloblastoma-Propagating Cells by a Combined Antagonism of Sonic Hedgehog and CXCR4.

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Ward, Stacey A; Warrington, Nicole M; Taylor, Sara; Kfoury, Najla; Luo, Jingqin; Rubin, Joshua B

2017-03-15

The CXCR4 chemokine and Sonic Hedgehog (SHH) morphogen pathways are well-validated therapeutic targets in cancer, including medulloblastoma. However, single-agent treatments with SHH or CXCR4 antagonists have not proven efficacious in clinical trials to date. Here, we discovered that dual inhibition of the SHH and CXCR4 pathways in a murine model of SHH-subtype medulloblastoma exerts potent antitumor effects. This therapeutic synergy resulted in the suppression of tumor-propagating cell function and correlated with increased histone H3 lysine 27 trimethylation within the promoters of stem cell genes, resulting in their decreased expression. These results demonstrate that CXCR4 contributes to the epigenetic regulation of a tumor-propagating cell phenotype. Moreover, they provide a mechanistic rationale to evaluate the combination of SHH and CXCR4 inhibitors in clinical trials for the treatment of medulloblastoma, as well as other cancers driven by SHH that coexpress high levels of CXCR4. Cancer Res; 77(6); 1416-26. ©2016 AACR . ©2016 American Association for Cancer Research.

Injury-stimulated Sonic hedgehog expression in microglia contributes to neuroinflammatory response in the MPTP model of Parkinson's disease

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Lee, Jeong Hwi; Chung, Young Cheul; Bok, Eugene; Lee, Hankyu; Huh, Sue Hee; Lee, Ji Eun; Jin, Byung Kwan; Ko, Hyuk Wan

2017-01-01

Parkinson's disease (PD) is a progressive neurodegenerative disorder in which dopamine (DA) neurons in the substantia nigra pars compacta (SNpc) region are selectively destroyed. Sonic hedgehog (Shh) has been well known to play a key role in a variety of processes such as embryogenesis, cell proliferation and protection, and tissue repair during inflammation. However, the evidences for the innate role of Shh in adult brain injury are presently lacking and studies have been needed to unveil the importance of Shh in the process of neurodegeneration. Here, we investigated the role of Shh in the pathologic progress of Parkinson's disease in MPTP-induced animal model system. Interestingly, we observed that Shh expression was gradually increased in MPTP affected SNpc region. Activated microglia exclusively expressed SHH in vivo and we could recapitulate Shh induction in activated cultured primary microglia cells. Using the SHH responsive Cre-loxP binary genetic reporter transgenic mouse system, we also found that most of the cell types except for oligodendrocyte in the SNpc region reacted to the SHH by MPTP injection. Taken together, activated microglia induced Shh expression and most neural cells except oligodendrocyte responded to microglia-derived SHH in MPTP-treated SN. These results suggest that SHH in activated microglia by MPTP-injection might be involved in the innate processes of recovery from neurotoxin induced injury in the PD animal model system. - Highlights: • Sonic hedgehog (Shh) was induced by MPTP neurotoxin at the Substantia Nigra (SN) in vivo. • Activated microglia are major cell type for SHH expression in vivo and in vitro. • Different types of cells in the brain, except oligodendrocyte, respond to microglia-derived SHH in SN region.

The Hedgehog Signal Induced Modulation of Bone Morphogenetic Protein Signaling: An Essential Signaling Relay for Urinary Tract Morphogenesis

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Nakagata, Naomi; Miyagawa, Shinichi; Suzuki, Kentaro; Kitazawa, Sohei; Yamada, Gen

2012-01-01

Background Congenital diseases of the urinary tract are frequently observed in infants. Such diseases present a number of developmental anomalies such as hydroureter and hydronephrosis. Although some genetically-modified mouse models of growth factor signaling genes reproduce urinary phenotypes, the pathogenic mechanisms remain obscure. Previous studies suggest that a portion of the cells in the external genitalia and bladder are derived from peri-cloacal mesenchymal cells that receive Hedgehog (Hh) signaling in the early developmental stages. We hypothesized that defects in such progenitor cells, which give rise to urinary tract tissues, may be a cause of such diseases. Methodology/Principal Findings To elucidate the pathogenic mechanisms of upper urinary tract malformations, we analyzed a series of Sonic hedgehog (Shh) deficient mice. Shh−/− displayed hydroureter and hydronephrosis phenotypes and reduced expression of several developmental markers. In addition, we suggested that Shh modulation at an early embryonic stage is responsible for such phenotypes by analyzing the Shh conditional mutants. Tissue contribution assays of Hh-responsive cells revealed that peri-cloacal mesenchymal cells, which received Hh signal secreted from cloacal epithelium, could contribute to the ureteral mesenchyme. Gain- and loss-of-functional mutants for Hh signaling revealed a correlation between Hh signaling and Bone morphogenetic protein (Bmp) signaling. Finally, a conditional ablation of Bmp receptor type IA (BmprIA) gene was examined in Hh-responsive cell lineages. This system thus made it possible to analyze the primary functions of the growth factor signaling relay. The defective Hh-to-Bmp signaling relay resulted in severe urinary tract phenotypes with a decrease in the number of Hh-responsive cells. Conclusions/Significance This study identified the essential embryonic stages for the pathogenesis of urinary tract phenotypes. These results suggested that Hh

Aberrant Hedgehog ligands induce progressive pancreatic fibrosis by paracrine activation of myofibroblasts and ductular cells in transgenic zebrafish.

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In Hye Jung

Full Text Available Hedgehog (Hh signaling is frequently up-regulated in fibrogenic pancreatic diseases including chronic pancreatitis and pancreatic cancer. Although recent series suggest exclusive paracrine activation of stromal cells by Hh ligands from epithelial components, debates still exist on how Hh signaling works in pathologic conditions. To explore how Hh signaling affects the pancreas, we investigated transgenic phenotypes in zebrafish that over-express either Indian Hh or Sonic Hh along with green fluorescence protein (GFP to enable real-time observation, or GFP alone as control, at the ptf1a domain. Transgenic embryos and zebrafish were serially followed for transgenic phenotypes, and investigated using quantitative reverse transcription-polymerase chain reaction (qRT-PCR, in situ hybridization, and immunohistochemistry. Over-expression of Ihh or Shh reveals virtually identical phenotypes. Hh induces morphologic changes in a developing pancreas without derangement in acinar differentiation. In older zebrafish, Hh induces progressive pancreatic fibrosis intermingled with proliferating ductular structures, which is accompanied by the destruction of the acinar structures. Both myofibroblasts and ductular are activated and proliferated by paracrine Hh signaling, showing restricted expression of Hh downstream components including Patched1 (Ptc1, Smoothened (Smo, and Gli1/2 in those Hh-responsive cells. Hh ligands induce matrix metalloproteinases (MMPs, especially MMP9 in all Hh-responsive cells, and transform growth factor-ß1 (TGFß1 only in ductular cells. Aberrant Hh over-expression, however, does not induce pancreatic tumors. On treatment with inhibitors, embryonic phenotypes are reversed by either cyclopamine or Hedgehog Primary Inhibitor-4 (HPI-4. Pancreatic fibrosis is only prevented by HPI-4. Our study provides strong evidence of Hh signaling which induces pancreatic fibrosis through paracrine activation of Hh-responsive cells in vivo. Induction of

Stromal cells expressing hedgehog-interacting protein regulate the proliferation of myeloid neoplasms

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Kobune, M; Iyama, S; Kikuchi, S; Horiguchi, H; Sato, T; Murase, K; Kawano, Y; Takada, K; Ono, K; Kamihara, Y; Hayashi, T; Miyanishi, K; Sato, Y; Takimoto, R; Kato, J

2012-01-01

Aberrant reactivation of hedgehog (Hh) signaling has been described in a wide variety of human cancers including cancer stem cells. However, involvement of the Hh-signaling system in the bone marrow (BM) microenvironment during the development of myeloid neoplasms is unknown. In this study, we assessed the expression of Hh-related genes in primary human CD34 + cells, CD34 + blastic cells and BM stromal cells. Both Indian Hh (Ihh) and its signal transducer, smoothened (SMO), were expressed in CD34 + acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS)-derived cells. However, Ihh expression was relatively low in BM stromal cells. Remarkably, expression of the intrinsic Hh-signaling inhibitor, human Hh-interacting protein (HHIP) in AML/MDS-derived stromal cells was markedly lower than in healthy donor-derived stromal cells. Moreover, HHIP expression levels in BM stromal cells highly correlated with their supporting activity for SMO + leukemic cells. Knockdown of HHIP gene in stromal cells increased their supporting activity although control cells marginally supported SMO + leukemic cell proliferation. The demethylating agent, 5-aza-2′-deoxycytidine rescued HHIP expression via demethylation of HHIP gene and reduced the leukemic cell-supporting activity of AML/MDS-derived stromal cells. This indicates that suppression of stromal HHIP could be associated with the proliferation of AML/MDS cells

Genotypic and phenotypic analysis of 396 individuals with mutations in Sonic Hedgehog.

Science.gov (United States)

Solomon, Benjamin D; Bear, Kelly A; Wyllie, Adrian; Keaton, Amelia A; Dubourg, Christele; David, Veronique; Mercier, Sandra; Odent, Sylvie; Hehr, Ute; Paulussen, Aimee; Clegg, Nancy J; Delgado, Mauricio R; Bale, Sherri J; Lacbawan, Felicitas; Ardinger, Holly H; Aylsworth, Arthur S; Bhengu, Ntombenhle Louisa; Braddock, Stephen; Brookhyser, Karen; Burton, Barbara; Gaspar, Harald; Grix, Art; Horovitz, Dafne; Kanetzke, Erin; Kayserili, Hulya; Lev, Dorit; Nikkel, Sarah M; Norton, Mary; Roberts, Richard; Saal, Howard; Schaefer, G B; Schneider, Adele; Smith, Erika K; Sowry, Ellen; Spence, M Anne; Shalev, Stavit A; Steiner, Carlos E; Thompson, Elizabeth M; Winder, Thomas L; Balog, Joan Z; Hadley, Donald W; Zhou, Nan; Pineda-Alvarez, Daniel E; Roessler, Erich; Muenke, Maximilian

2012-07-01

Holoprosencephaly (HPE), the most common malformation of the human forebrain, may result from mutations in over 12 genes. Sonic Hedgehog (SHH) was the first such gene discovered; mutations in SHH remain the most common cause of non-chromosomal HPE. The severity spectrum is wide, ranging from incompatibility with extrauterine life to isolated midline facial differences. To characterise genetic and clinical findings in individuals with SHH mutations. Through the National Institutes of Health and collaborating centres, DNA from approximately 2000 individuals with HPE spectrum disorders were analysed for SHH variations. Clinical details were examined and combined with published cases. This study describes 396 individuals, representing 157 unrelated kindreds, with SHH mutations; 141 (36%) have not been previously reported. SHH mutations more commonly resulted in non-HPE (64%) than frank HPE (36%), and non-HPE was significantly more common in patients with SHH than in those with mutations in the other common HPE related genes (pC-terminus (including accounting for the relative size of the coding regions, p=0.00010), no specific genotype-phenotype correlations could be established regarding mutation location. SHH mutations overall result in milder disease than mutations in other common HPE related genes. HPE is more frequent in individuals with truncating mutations, but clinical predictions at the individual level remain elusive.

Regulation of hedgehog signaling by Myc-interacting zinc finger protein 1, Miz1.

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Jiuyi Lu

Full Text Available Smoothened (Smo mediated Hedgehog (Hh signaling plays an essential role in regulating embryonic development and postnatal tissue homeostasis. Aberrant activation of the Hh pathway contributes to the formation and progression of various cancers. In vertebrates, however, key regulatory mechanisms responsible for transducing signals from Smo to the nucleus remain to be delineated. Here, we report the identification of Myc-interacting Zinc finger protein 1 (Miz1 as a Smo and Gli2 binding protein that positively regulates Hh signaling. Overexpression of Miz1 increases Gli luciferase reporter activity, whereas knockdown of endogenous Miz1 has the opposite effect. Activation of Smo induces translocation of Miz1 to the primary cilia together with Smo and Gli2. Furthermore, Miz1 is localized to the nucleus upon Hh activation in a Smo-dependent manner, and loss of Miz1 prevents the nuclear translocation of Gli2. More importantly, silencing Miz1 expression inhibits cell proliferation in vitro and the growth of Hh-driven medulloblastoma tumors allografted in SCID mice. Taken together, these results identify Miz1 as a novel regulator in the Hh pathway that plays an important role in mediating Smo-dependent oncogenic signaling.

Deletion of Indian hedgehog gene causes dominant semi-lethal Creeper trait in chicken

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Jin, Sihua; Zhu, Feng; Wang, Yanyun; Yi, Guoqiang; Li, Junying; Lian, Ling; Zheng, Jiangxia; Xu, Guiyun; Jiao, Rengang; Gong, Yu; Hou, Zhuocheng; Yang, Ning

2016-01-01

The Creeper trait, a classical monogenic phenotype of chicken, is controlled by a dominant semi-lethal gene. This trait has been widely cited in the genetics and molecular biology textbooks for illustrating autosomal dominant semi-lethal inheritance over decades. However, the genetic basis of the Creeper trait remains unknown. Here we have utilized ultra-deep sequencing and extensive analysis for targeting causative mutation controlling the Creeper trait. Our results indicated that the deletion of Indian hedgehog (IHH) gene was only found in the whole-genome sequencing data of lethal embryos and Creeper chickens. Large scale segregation analysis demonstrated that the deletion of IHH was fully linked with early embryonic death and the Creeper trait. Expression analysis showed a much lower expression of IHH in Creeper than wild-type chickens. We therefore suggest the deletion of IHH to be the causative mutation for the Creeper trait in chicken. Our findings unravel the genetic basis of the longstanding Creeper phenotype mystery in chicken as the same gene also underlies bone dysplasia in human and mouse, and thus highlight the significance of IHH in animal development and human haploinsufficiency disorders. PMID:27439785

Mangiferin treatment inhibits hepatic expression of acyl-coenzyme A:diacylglycerol acyltransferase-2 in fructose-fed spontaneously hypertensive rats: a link to amelioration of fatty liver

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Xing, Xiaomang; Li, Danyang; Chen, Dilong; Zhou, Liang [Faculty of Basic Medical Sciences, Chongqing Medical University, Chongqing 400016 China (China); Chonan, Ritsu [Koei Kogyo Co., Ltd., Tokyo, 101-0063 Japan (Japan); Yamahara, Johji [Pharmafood Institute, Kyoto, 602-8136 Japan (Japan); Wang, Jianwei, E-mail: wangjianwei1968@gmail.com [Department of Traditional Chinese Medicine, Chongqing Medical University, Chongqing 400016 China (China); Li, Yuhao, E-mail: yuhao@sitcm.edu.au [Endocrinology and Metabolism Group, Sydney Institute of Health Sciences/Sydney Institute of Traditional Chinese Medicine, NSW 2000 Australia (Australia)

2014-10-15

Mangiferin, a xanthone glucoside, and its associated traditional herbs have been demonstrated to improve abnormalities of lipid metabolism. However, its underlying mechanisms remain largely unclear. This study investigated the anti-steatotic effect of mangiferin in fructose-fed spontaneously hypertensive rat (SHR)s that have a mutation in sterol regulatory element binding protein (SREBP)-1. The results showed that co-administration of mangiferin (15 mg/kg, once daily, by oral gavage) over 7 weeks dramatically diminished fructose-induced increases in hepatic triglyceride content and Oil Red O-stained area in SHRs. However, blood pressure, fructose and chow intakes, white adipose tissue weight and metabolic parameters (plasma concentrations of glucose, insulin, triglyceride, total cholesterol and non-esterified fatty acids) were unaffected by mangiferin treatment. Mechanistically, mangiferin treatment suppressed acyl-coenzyme A:diacylglycerol acyltransferase (DGAT)-2 expression at the mRNA and protein levels in the liver. In contrast, mangiferin treatment was without effect on hepatic mRNA and/or protein expression of SREBP-1/1c, carbohydrate response element binding protein, liver pyruvate kinase, fatty acid synthase, acetyl-CoA carboxylase-1, stearoyl-CoA desaturase-1, DGAT-1, monoacyglycerol acyltransferase-2, microsomal triglyceride transfer protein, peroxisome proliferator-activated receptor-alpha, carnitine palmitoyltransferase-1 and acyl-CoA oxidase. Collectively, our results suggest that mangiferin treatment ameliorates fatty liver in fructose-fed SHRs by inhibiting hepatic DGAT-2 that catalyzes the final step in triglyceride biosynthesis. The anti-steatotic effect of mangiferin may occur independently of the hepatic signals associated with de novo fatty acid synthesis and oxidation. - Highlights: • We investigated the anti-steatotic effect of mangiferin (MA) in fructose-fed SHR. • MA (15 mg/kg/day for 7 weeks) ameliorated fructose-induced fatty liver in

Mangiferin treatment inhibits hepatic expression of acyl-coenzyme A:diacylglycerol acyltransferase-2 in fructose-fed spontaneously hypertensive rats: a link to amelioration of fatty liver

International Nuclear Information System (INIS)

Xing, Xiaomang; Li, Danyang; Chen, Dilong; Zhou, Liang; Chonan, Ritsu; Yamahara, Johji; Wang, Jianwei; Li, Yuhao

2014-01-01

Mangiferin, a xanthone glucoside, and its associated traditional herbs have been demonstrated to improve abnormalities of lipid metabolism. However, its underlying mechanisms remain largely unclear. This study investigated the anti-steatotic effect of mangiferin in fructose-fed spontaneously hypertensive rat (SHR)s that have a mutation in sterol regulatory element binding protein (SREBP)-1. The results showed that co-administration of mangiferin (15 mg/kg, once daily, by oral gavage) over 7 weeks dramatically diminished fructose-induced increases in hepatic triglyceride content and Oil Red O-stained area in SHRs. However, blood pressure, fructose and chow intakes, white adipose tissue weight and metabolic parameters (plasma concentrations of glucose, insulin, triglyceride, total cholesterol and non-esterified fatty acids) were unaffected by mangiferin treatment. Mechanistically, mangiferin treatment suppressed acyl-coenzyme A:diacylglycerol acyltransferase (DGAT)-2 expression at the mRNA and protein levels in the liver. In contrast, mangiferin treatment was without effect on hepatic mRNA and/or protein expression of SREBP-1/1c, carbohydrate response element binding protein, liver pyruvate kinase, fatty acid synthase, acetyl-CoA carboxylase-1, stearoyl-CoA desaturase-1, DGAT-1, monoacyglycerol acyltransferase-2, microsomal triglyceride transfer protein, peroxisome proliferator-activated receptor-alpha, carnitine palmitoyltransferase-1 and acyl-CoA oxidase. Collectively, our results suggest that mangiferin treatment ameliorates fatty liver in fructose-fed SHRs by inhibiting hepatic DGAT-2 that catalyzes the final step in triglyceride biosynthesis. The anti-steatotic effect of mangiferin may occur independently of the hepatic signals associated with de novo fatty acid synthesis and oxidation. - Highlights: • We investigated the anti-steatotic effect of mangiferin (MA) in fructose-fed SHR. • MA (15 mg/kg/day for 7 weeks) ameliorated fructose-induced fatty liver in

Reduction of dietary saturated fatty acids correlates with increased plasma lecithin cholesterol acyltransferase activity in humans.

Science.gov (United States)

Bérard, A M; Dabadie, H; Palos-Pinto, A; Dumon, M-F; Darmon, M

2004-06-01

Increased HDL-cholesterol (HDL-C) concentrations have been associated with lower coronary heart disease risk. On the other hand, dietary fats are known to influence the fatty acid profile of plasma lipids, including phospholipids that are substrates of lecithin cholesterol acyltransferase (LCAT), an important enzyme in HDL metabolism. The purpose of this study was to examine the association between the saturated fatty acid (SFA) intake and LCAT activity. An interventional study was performed in a monk community of 25 men. A French monk community, South West of France. The basal diet of the study cohort contained SFA in a proportion of 13.5% of their total energy intake (TEI). They were submitted to two experimental isocaloric diets containing either 8.4% of the TEI in SFA (diet A) or 11% (diet B), each lasting 5 weeks. The elevation of SFA in diet B was mainly obtained by decreasing carbohydrates. The only significant difference among total fats between diets A and B was the myristic acid content (0.6 and 1.2% of TEI, respectively). The elevation in SFA in diet B resulted in a significant increase of HDL-C (P<0.04), while plasma apo A-I concentration and LCAT activity both decreased (P<0.02). Altogether, these results are consistent with a negative effect of SFA on reverse cholesterol transport.

NCBI nr-aa BLAST: CBRC-CBRI-05-0288 [SEVENS

Lifescience Database Archive (English)

Full Text Available CBRC-CBRI-05-0288 ref|YP_512974.1| Acyltransferase [Francisella tularensis subsp. h...olarctica] ref|YP_762841.1| acyltransferase [Francisella tularensis subsp. holarctica OSU18] ref|YP_001427626.1| acyltransferase [Fra...ncisella tularensis subsp. holarctica FTA] emb|CAJ78620.1| Acyltransferase [Francis...ella tularensis subsp. holarctica LVS] gb|ABI82204.1| acyltransferase [Francisell...a tularensis subsp. holarctica OSU18] gb|EBA51928.1| acyltransferase [Francisella tularensis subsp. holarcti

TRAIL, Wnt, Sonic Hedgehog, TGFβ, and miRNA Signalings Are Potential Targets for Oral Cancer Therapy.

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Farooqi, Ammad Ahmad; Shu, Chih-Wen; Huang, Hurng-Wern; Wang, Hui-Ru; Chang, Yung-Ting; Fayyaz, Sundas; Yuan, Shyng-Shiou F; Tang, Jen-Yang; Chang, Hsueh-Wei

2017-07-14

Clinical studies and cancer cell models emphasize the importance of targeting therapies for oral cancer. The tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is highly expressed in cancer, and is a selective killing ligand for oral cancer. Signaling proteins in the wingless-type mouse mammary tumor virus (MMTV) integration site family (Wnt), Sonic hedgehog (SHH), and transforming growth factor β (TGFβ) pathways may regulate cell proliferation, migration, and apoptosis. Accordingly, the genes encoding these signaling proteins are potential targets for oral cancer therapy. In this review, we focus on recent advances in targeting therapies for oral cancer and discuss the gene targets within TRAIL, Wnt, SHH, and TGFβ signaling for oral cancer therapies. Oncogenic microRNAs (miRNAs) and tumor suppressor miRNAs targeting the genes encoding these signaling proteins are summarized, and the interactions between Wnt, SHH, TGFβ, and miRNAs are interpreted. With suitable combination treatments, synergistic effects are expected to improve targeting therapies for oral cancer.

TRAIL, Wnt, Sonic Hedgehog, TGFβ, and miRNA Signalings Are Potential Targets for Oral Cancer Therapy

Science.gov (United States)

Farooqi, Ammad Ahmad; Shu, Chih-Wen; Huang, Hurng-Wern; Wang, Hui-Ru; Chang, Yung-Ting; Fayyaz, Sundas; Yuan, Shyng-Shiou F.; Tang, Jen-Yang

2017-01-01

Clinical studies and cancer cell models emphasize the importance of targeting therapies for oral cancer. The tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is highly expressed in cancer, and is a selective killing ligand for oral cancer. Signaling proteins in the wingless-type mouse mammary tumor virus (MMTV) integration site family (Wnt), Sonic hedgehog (SHH), and transforming growth factor β (TGFβ) pathways may regulate cell proliferation, migration, and apoptosis. Accordingly, the genes encoding these signaling proteins are potential targets for oral cancer therapy. In this review, we focus on recent advances in targeting therapies for oral cancer and discuss the gene targets within TRAIL, Wnt, SHH, and TGFβ signaling for oral cancer therapies. Oncogenic microRNAs (miRNAs) and tumor suppressor miRNAs targeting the genes encoding these signaling proteins are summarized, and the interactions between Wnt, SHH, TGFβ, and miRNAs are interpreted. With suitable combination treatments, synergistic effects are expected to improve targeting therapies for oral cancer. PMID:28708091

Formation of the sacrum requires down-regulation of sonic hedgehog signaling in the sacral intervertebral discs.

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Bonavita, Raffaella; Vincent, Kathleen; Pinelli, Robert; Dahia, Chitra Lekha

2018-05-21

In humans, the sacrum forms an important component of the pelvic arch, and it transfers the weight of the body to the lower limbs. The sacrum is formed by collapse of the intervertebral discs (IVDs) between the five sacral vertebrae during childhood, and their fusion to form a single bone. We show that collapse of the sacral discs in the mouse is associated with the down-regulation of sonic hedgehog (SHH) signaling in the nucleus pulposus (NP) of the disc, and many aspects of this phenotype can be reversed by experimental postnatal activation of HH signaling. We have previously shown that SHH signaling is essential for the normal postnatal growth and differentiation of intervertebral discs elsewhere in the spine, and that loss of SHH signaling leads to pathological disc degeneration, a very common disorder of aging. Thus, loss of SHH is pathological in one region of the spine but part of normal development in another. © 2018. Published by The Company of Biologists Ltd.

The hedgehog receptor patched is involved in cholesterol transport.

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Michel Bidet

Full Text Available Sonic hedgehog (Shh signaling plays a crucial role in growth and patterning during embryonic development, and also in stem cell maintenance and tissue regeneration in adults. Aberrant Shh pathway activation is involved in the development of many tumors, and one of the most affected Shh signaling steps found in these tumors is the regulation of the signaling receptor Smoothened by the Shh receptor Patched. In the present work, we investigated Patched activity and the mechanism by which Patched inhibits Smoothened.Using the well-known Shh-responding cell line of mouse fibroblasts NIH 3T3, we first observed that enhancement of the intracellular cholesterol concentration induces Smoothened enrichment in the plasma membrane, which is a crucial step for the signaling activation. We found that binding of Shh protein to its receptor Patched, which involves Patched internalization, increases the intracellular concentration of cholesterol and decreases the efflux of a fluorescent cholesterol derivative (BODIPY-cholesterol from these cells. Treatment of fibroblasts with cyclopamine, an antagonist of Shh signaling, inhibits Patched expression and reduces BODIPY-cholesterol efflux, while treatment with the Shh pathway agonist SAG enhances Patched protein expression and BODIPY-cholesterol efflux. We also show that over-expression of human Patched in the yeast S. cerevisiae results in a significant boost of BODIPY-cholesterol efflux. Furthermore, we demonstrate that purified Patched binds to cholesterol, and that the interaction of Shh with Patched inhibits the binding of Patched to cholesterol.Our results suggest that Patched may contribute to cholesterol efflux from cells, and to modulation of the intracellular cholesterol concentration. This activity is likely responsible for the inhibition of the enrichment of Smoothened in the plasma membrane, which is an important step in Shh pathway activation.

Sonic hedgehog signaling regulates amygdalar neurogenesis and extinction of fear memory.

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Hung, Hui-Chi; Hsiao, Ya-Hsin; Gean, Po-Wu

2015-10-01

It is now recognized that neurogenesis occurs throughout life predominantly in the subgranular zone (SGZ) of the hippocampus and the subventricular zone (SVZ) of the lateral ventricle. In the present study, we investigated the relationship between neurogenesis in the amygdala and extinction of fear memory. Mice received 15 tone-footshock pairings. Twenty-four hours after training, the mice were given 15 tone-alone trials (extinction training) once per day for 7 days. Two hours before extinction training, the mice were injected intraperitoneally with 5-bromo-3-deoxyuridine (BrdU). BrdU-positive and NeuN-positive cells were analyzed 52 days after the training. A group of mice that received tone-footshock pairings but no extinction training served as controls (FC+No-Ext). The number of BrdU(+)/NeuN(+) cells was significantly higher in the extinction (FC+Ext) than in the FC+No-Ext mice. Proliferation inhibitor methylazoxymethanol acetate (MAM) or DNA synthesis inhibitor cytosine arabinoside (Ara-C) reduced neurogenesis and retarded extinction. Silencing Sonic hedgehog (Shh) gene with short hairpin interfering RNA (shRNA) by means of a retrovirus expression system to knockdown Shh specifically in the mitotic neurons reduced neurogenesis and retarded extinction. By contrast, over-expression of Shh increased neurogenesis and facilitated extinction. These results suggest that amygdala neurogenesis and Shh signaling are involved in the extinction of fear memory. Copyright © 2015 Elsevier B.V. and ECNP. All rights reserved.

Absolute requirement of cholesterol binding for Hedgehog gradient formation in Drosophila

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Antoine Ducuing

2013-05-01

How morphogen gradients are shaped is a major question in developmental biology, but remains poorly understood. Hedgehog (Hh is a locally secreted ligand that reaches cells at a distance and acts as a morphogen to pattern the Drosophila wing and the vertebrate neural tube. The proper patterning of both structures relies on the precise control over the slope of Hh activity gradient. A number of hypotheses have been proposed to explain Hh movement and hence graded activity of Hh. A crux to all these models is that the covalent binding of cholesterol to Hh N-terminus is essential to achieve the correct slope of the activity gradient. Still, the behavior of cholesterol-free Hh (Hh-N remains controversial: cholesterol has been shown to either increase or restrict Hh range depending on the experimental setting. Here, in fly embryos and wing imaginal discs, we show that cholesterol-free Hh diffuses at a long-range. This unrestricted diffusion of cholesterol-free Hh leads to an absence of gradient while Hh signaling strength remains uncompromised. These data support a model where cholesterol addition restricts Hh diffusion and can transform a leveled signaling activity into a gradient. In addition, our data indicate that the receptor Patched is not able to sequester cholesterol-free Hh. We propose that a morphogen gradient does not necessarily stem from the active transfer of a poorly diffusing molecule, but can be achieved by the restriction of a highly diffusible ligand.

Contribution of hedgehog signaling to the establishment of left-right asymmetry in the sea urchin.

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Warner, Jacob F; Miranda, Esther L; McClay, David R

2016-03-15

Most bilaterians exhibit a left-right asymmetric distribution of their internal organs. The sea urchin larva is notable in this regard since most adult structures are generated from left sided embryonic structures. The gene regulatory network governing this larval asymmetry is still a work in progress but involves several conserved signaling pathways including Nodal, and BMP. Here we provide a comprehensive analysis of Hedgehog signaling and it's contribution to left-right asymmetry. We report that Hh signaling plays a conserved role to regulate late asymmetric expression of Nodal and that this regulation occurs after Nodal breaks left-right symmetry in the mesoderm. Thus, while Hh functions to maintain late Nodal expression, the molecular asymmetry of the future coelomic pouches is locked in. Furthermore we report that cilia play a role only insofar as to transduce Hh signaling and do not have an independent effect on the asymmetry of the mesoderm. From this, we are able to construct a more complete regulatory network governing the establishment of left-right asymmetry in the sea urchin. Copyright © 2016 Elsevier Inc. All rights reserved.

Complete and sustained response of adult medulloblastoma to first-line sonic hedgehog inhibition with vismodegib.

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Lou, Emil; Schomaker, Matthew; Wilson, Jon D; Ahrens, Mary; Dolan, Michelle; Nelson, Andrew C

2016-08-12

Medulloblastoma is an aggressive primitive neuroectodermal tumor of the cerebellum that is rare in adults. Medulloblastomas fall into 4 prognostically significant molecular subgroups that are best defined by experimental gene expression profiles: the WNT pathway, sonic hedgehog (SHH) pathway, and subgroups 3 and 4 (non-SHH/WNT). Medulloblastoma of adults belong primarily to the SHH category. Vismodegib, an SHH-pathway inhibitor FDA-approved in 2012 for treatment of basal cell carcinoma, has been used successfully in the setting of chemorefractory medulloblastoma, but not as a first-line therapy. In this report, we describe a sustained response of an unresectable multifocal form of adult medulloblastoma to vismodegib. Molecular analysis in this case revealed mutations in TP53 and a cytogenetic abnormality, i17q, that is prevalent and most often associated with subgroup 4 rather than the SHH-activated form of medulloblastoma. Our findings indicate that vismodegib may also block alternate, non-canonical forms of downstream SHH pathway activation. These findings provide strong impetus for further investigation of vismodegib in clinical trials in the first-line setting for pediatric and adult forms of medulloblastoma.

SDCCAG8 Interacts with RAB Effector Proteins RABEP2 and ERC1 and Is Required for Hedgehog Signaling

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Airik, Rannar; Schueler, Markus; Airik, Merlin

2016-01-01

Recessive mutations in the SDCCAG8 gene cause a nephronophthisis-related ciliopathy with Bardet-Biedl syndrome-like features in humans. Our previous characterization of the orthologous Sdccag8gt/gt mouse model recapitulated the retinal-renal disease phenotypes and identified impaired DNA damage...... response signaling as an underlying disease mechanism in the kidney. However, several other phenotypic and mechanistic features of Sdccag8gt/gt mice remained unexplored. Here we show that Sdccag8gt/gt mice exhibit developmental and structural abnormalities of the skeleton and limbs, suggesting impaired...... Hedgehog (Hh) signaling. Indeed, cell culture studies demonstrate the requirement of SDCCAG8 for ciliogenesis and Hh signaling. Using an affinity proteomics approach, we demonstrate that SDCCAG8 interacts with proteins of the centriolar satellites (OFD1, AZI1), of the endosomal sorting complex (RABEP2, ERC...

The Mitochondrial Cardiolipin Remodeling Enzyme Lysocardiolipin Acyltransferase Is a Novel Target in Pulmonary Fibrosis

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Huang, Long Shuang; Mathew, Biji; Zhao, Yutong; Noth, Imre; Reddy, Sekhar P.; Harijith, Anantha; Usatyuk, Peter V.; Berdyshev, Evgeny V.; Kaminski, Naftali; Zhou, Tong; Zhang, Wei; Zhang, Yanmin; Rehman, Jalees; Kotha, Sainath R.; Gurney, Travis O.; Parinandi, Narasimham L.; Lussier, Yves A.; Garcia, Joe G. N.

2014-01-01

Rationale: Lysocardiolipin acyltransferase (LYCAT), a cardiolipin-remodeling enzyme regulating the 18:2 linoleic acid pattern of mammalian mitochondrial cardiolipin, is necessary for maintaining normal mitochondrial function and vascular development. We hypothesized that modulation of LYCAT expression in lung epithelium regulates development of pulmonary fibrosis. Objectives: To define a role for LYCAT in human and murine models of pulmonary fibrosis. Methods: We analyzed the correlation of LYCAT expression in peripheral blood mononuclear cells (PBMCs) with the outcomes of pulmonary functions and overall survival, and used the murine models to establish the role of LYCAT in fibrogenesis. We studied the LYCAT action on cardiolipin remodeling, mitochondrial reactive oxygen species generation, and apoptosis of alveolar epithelial cells under bleomycin challenge. Measurements and Main Results: LYCAT expression was significantly altered in PBMCs and lung tissues from patients with idiopathic pulmonary fibrosis (IPF), which was confirmed in two preclinical murine models of IPF, bleomycin- and radiation-induced pulmonary fibrosis. LYCAT mRNA expression in PBMCs directly and significantly correlated with carbon monoxide diffusion capacity, pulmonary function outcomes, and overall survival. In both bleomycin- and radiation-induced pulmonary fibrosis murine models, hLYCAT overexpression reduced several indices of lung fibrosis, whereas down-regulation of native LYCAT expression by siRNA accentuated fibrogenesis. In vitro studies demonstrated that LYCAT modulated bleomycin-induced cardiolipin remodeling, mitochondrial membrane potential, reactive oxygen species generation, and apoptosis of alveolar epithelial cells, potential mechanisms of LYCAT-mediated lung protection. Conclusions: This study is the first to identify modulation of LYCAT expression in fibrotic lungs and offers a novel therapeutic approach for ameliorating lung inflammation and pulmonary fibrosis. PMID

Functional group and stereochemical requirements for substrate binding by ghrelin O-acyltransferase revealed by unnatural amino acid incorporation.

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Cleverdon, Elizabeth R; Davis, Tasha R; Hougland, James L

2018-04-21

Ghrelin is a small peptide hormone that undergoes a unique posttranslational modification, serine octanoylation, to play its physiological roles in processes including hunger signaling and glucose metabolism. Ghrelin O-acyltransferase (GOAT) catalyzes this posttranslational modification, which is essential for ghrelin to bind and activate its cognate GHS-R1a receptor. Inhibition of GOAT offers a potential avenue for modulating ghrelin signaling for therapeutic effect. Defining the molecular characteristics of ghrelin that lead to binding and recognition by GOAT will facilitate the development and optimization of GOAT inhibitors. We show that small peptide mimics of ghrelin substituted with 2,3-diaminopropanoic acid in place of the serine at the site of octanoylation act as submicromolar inhibitors of GOAT. Using these chemically modified analogs of desacyl ghrelin, we define key functional groups within the N-terminal sequence of ghrelin essential for binding to GOAT and determine GOAT's tolerance to backbone methylations and altered amino acid stereochemistry within ghrelin. Our study provides a structure-activity analysis of ghrelin binding to GOAT that expands upon activity-based investigations of ghrelin recognition and establishes a new class of potent substrate-mimetic GOAT inhibitors for further investigation and therapeutic interventions targeting ghrelin signaling. Copyright © 2018 Elsevier Inc. All rights reserved.

Indian hedgehog signaling triggers Nkx3.2 protein degradation during chondrocyte maturation

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Choi, Seung-Won; Jeong, Da-Un; Kim, Jeong-Ah; Lee, Boyoung; Joeng, Kyu Sang; Long, Fanxin; Kim, Dae-Won

2015-01-01

The Indian hedgehog (Ihh) pathway plays an essential role in facilitating chondrocyte hypertrophy and bone formation during skeletal development. Nkx3.2 is initially induced in chondrocyte precursor cells, maintained in early-stage chondrocytes, and down-regulated in terminal-stage chondrocytes. Consistent with these expression patterns, Nkx3.2 has been shown to enhance chondrocyte differentiation and cell survival, while inhibiting chondrocyte hypertrophy and apoptosis. Thus, in this work, we investigate whether Nkx3.2, an early stage chondrogenic factor, can be regulated by Ihh, a key regulator for chondrocyte hypertrophy. Here, we show that Ihh signaling can induce proteasomal degradation of Nkx3.2. In addition, we found that Ihh can suppress levels of Lrp (Wnt co-receptor) and Sfrp (Wnt antagonist) expression, which, in turn, may selectively enhance Lrp-independent non-canonical Wnt pathways in chondrocyte. In agreement with these findings, Ihh-induced Nkx3.2 degradation requires Wnt5a, which is capable of triggering Nkx3.2 degradation. Finally, we found that Nkx3.2 protein levels in chondrocytes are remarkably elevated in mice defective in Ihh signaling by deletion of either Ihh or Smoothened. Thus, these results suggest that Ihh/Wnt5a signaling may play a role in negative regulation of Nkx3.2 for appropriate progression of chondrocyte hypertrophy during chondrogenesis. PMID:22507129

Sonic hedgehog initiates cochlear hair cell regeneration through downregulation of retinoblastoma protein

International Nuclear Information System (INIS)

Lu, Na; Chen, Yan; Wang, Zhengmin; Chen, Guoling; Lin, Qin; Chen, Zheng-Yi; Li, Huawei

2013-01-01

Highlights: ► Shh activation in neonatal cochleae enhances sensory cell proliferation. ► Proliferating supporting cells can transdifferentiate into hair cells. ► Shh promotes proliferation by transiently modulating pRb activity. ► Shh inhibits pRb by inhibiting transcription and increasing phosphorylation of pRb. -- Abstract: Cell cycle re-entry by cochlear supporting cells and/or hair cells is considered one of the best approaches for restoring hearing loss as a result of hair cell damage. To identify mechanisms that can be modulated to initiate cell cycle re-entry and hair cell regeneration, we studied the effect of activating the sonic hedgehog (Shh) pathway. We show that Shh signaling in postnatal rat cochleae damaged by neomycin leads to renewed proliferation of supporting cells and hair cells. Further, proliferating supporting cells are likely to transdifferentiate into hair cells. Shh treatment leads to inhibition of retinoblastoma protein (pRb) by increasing phosphorylated pRb and reducing retinoblastoma gene transcription. This results in upregulation of cyclins B1, D2, and D3, and CDK1. These results suggest that Shh signaling induces cell cycle re-entry in cochlear sensory epithelium and the production of new hair cells, in part by attenuating pRb function. This study provides an additional route to modulate pRb function with important implications in mammalian hair cell regeneration.

A genome-wide RNAi screen identifies regulators of cholesterol-modified hedgehog secretion in Drosophila.

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Reid Aikin

Full Text Available Hedgehog (Hh proteins are secreted molecules that function as organizers in animal development. In addition to being palmitoylated, Hh is the only metazoan protein known to possess a covalently-linked cholesterol moiety. The absence of either modification severely disrupts the organization of numerous tissues during development. It is currently not known how lipid-modified Hh is secreted and released from producing cells. We have performed a genome-wide RNAi screen in Drosophila melanogaster cells to identify regulators of Hh secretion. We found that cholesterol-modified Hh secretion is strongly dependent on coat protein complex I (COPI but not COPII vesicles, suggesting that cholesterol modification alters the movement of Hh through the early secretory pathway. We provide evidence that both proteolysis and cholesterol modification are necessary for the efficient trafficking of Hh through the ER and Golgi. Finally, we identified several putative regulators of protein secretion and demonstrate a role for some of these genes in Hh and Wingless (Wg morphogen secretion in vivo. These data open new perspectives for studying how morphogen secretion is regulated, as well as provide insight into regulation of lipid-modified protein secretion.

Differential Cellular Responses to Hedgehog Signalling in Vertebrates—What is the Role of Competence?

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Kiecker, Clemens; Graham, Anthony; Logan, Malcolm

2016-01-01

A surprisingly small number of signalling pathways generate a plethora of cellular responses ranging from the acquisition of multiple cell fates to proliferation, differentiation, morphogenesis and cell death. These diverse responses may be due to the dose-dependent activities of signalling factors, or to intrinsic differences in the response of cells to a given signal—a phenomenon called differential cellular competence. In this review, we focus on temporal and spatial differences in competence for Hedgehog (HH) signalling, a signalling pathway that is reiteratively employed in embryos and adult organisms. We discuss the upstream signals and mechanisms that may establish differential competence for HHs in a range of different tissues. We argue that the changing competence for HH signalling provides a four-dimensional framework for the interpretation of the signal that is essential for the emergence of functional anatomy. A number of diseases—including several types of cancer—are caused by malfunctions of the HH pathway. A better understanding of what provides differential competence for this signal may reveal HH-related disease mechanisms and equip us with more specific tools to manipulate HH signalling in the clinic. PMID:29615599

Differential Cellular Responses to Hedgehog Signalling in Vertebrates—What is the Role of Competence?

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Clemens Kiecker

2016-12-01

Full Text Available A surprisingly small number of signalling pathways generate a plethora of cellular responses ranging from the acquisition of multiple cell fates to proliferation, differentiation, morphogenesis and cell death. These diverse responses may be due to the dose-dependent activities of signalling factors, or to intrinsic differences in the response of cells to a given signal—a phenomenon called differential cellular competence. In this review, we focus on temporal and spatial differences in competence for Hedgehog (HH signalling, a signalling pathway that is reiteratively employed in embryos and adult organisms. We discuss the upstream signals and mechanisms that may establish differential competence for HHs in a range of different tissues. We argue that the changing competence for HH signalling provides a four-dimensional framework for the interpretation of the signal that is essential for the emergence of functional anatomy. A number of diseases—including several types of cancer—are caused by malfunctions of the HH pathway. A better understanding of what provides differential competence for this signal may reveal HH-related disease mechanisms and equip us with more specific tools to manipulate HH signalling in the clinic.

Glycerol-3-phosphate acyltransferase 2 expression modulates cell roughness and membrane permeability: An atomic force microscopy study.

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Elizabeth R Cattaneo

Full Text Available In mammalian cells, de novo glycerolipid synthesis begins with the acylation of glycerol-3-phosphate, catalyzed by glycerol-3-phosphate acyltransferases (GPAT. GPAT2 is a mitochondrial isoform primarily expressed in testis under physiological conditions, and overexpressed in several types of cancers and cancer-derived human cell lines where its expression contributes to the tumor phenotype. Using gene silencing and atomic force microscopy, we studied the correlation between GPAT2 expression and cell surface topography, roughness and membrane permeability in MDA-MB-231 cells. In addition, we analyzed the glycerolipid composition by gas-liquid chromatography. GPAT2 expression altered the arachidonic acid content in glycerolipids, and the lack of GPAT2 seems to be partially compensated by the overexpression of another arachidonic-acid-metabolizing enzyme, AGPAT11. GPAT2 expressing cells exhibited a rougher topography and less membrane damage than GPAT2 silenced cells. Pore-like structures were present only in GPAT2 subexpressing cells, correlating with higher membrane damage evidenced by lactate dehydrogenase release. These GPAT2-induced changes are consistent with its proposed function as a tumor-promoting gene, and might be used as a phenotypic differentiation marker. AFM provides the basis for the identification and quantification of those changes, and demonstrates the utility of this technique in the study of cancer cell biology.

Plant Acyl-CoA:Lysophosphatidylcholine Acyltransferases (LPCATs) Have Different Specificities in Their Forward and Reverse Reactions*

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Lager, Ida; Yilmaz, Jenny Lindberg; Zhou, Xue-Rong; Jasieniecka, Katarzyna; Kazachkov, Michael; Wang, Peng; Zou, Jitao; Weselake, Randall; Smith, Mark A.; Bayon, Shen; Dyer, John M.; Shockey, Jay M.; Heinz, Ernst; Green, Allan; Banas, Antoni; Stymne, Sten

2013-01-01

Acyl-CoA:lysophosphatidylcholine acyltransferase (LPCAT) enzymes have central roles in acyl editing of phosphatidylcholine (PC). Plant LPCAT genes were expressed in yeast and characterized biochemically in microsomal preparations of the cells. Specificities for different acyl-CoAs were similar for seven LPCATs from five different species, including species accumulating hydroxylated acyl groups in their seed oil, with a preference for C18-unsaturated acyl-CoA and low activity with palmitoyl-CoA and ricinoleoyl (12-hydroxyoctadec-9-enoyl)-CoA. We showed that Arabidopsis LPCAT1 and LPCAT2 enzymes catalyzed the acylation and de-acylation of both sn positions of PC, with a preference for the sn-2 position. When acyl specificities of the Arabidopsis LPCATs were measured in the reverse reaction, sn-2-bound oleoyl, linoleoyl, and linolenoyl groups from PC were transferred to acyl-CoA to a similar extent. However, a ricinoleoyl group at the sn-2-position of PC was removed 4–6-fold faster than an oleoyl group in the reverse reaction, despite poor utilization in the forward reaction. The data presented, taken together with earlier published reports on in vivo lipid metabolism, support the hypothesis that plant LPCAT enzymes play an important role in regulating the acyl-CoA composition in plant cells by transferring polyunsaturated and hydroxy fatty acids produced on PC directly to the acyl-CoA pool for further metabolism or catabolism. PMID:24189065

First report of acariasis by Caparinia tripilis in African hedgehogs, (Atelerix albiventris, in Costa Rica Primeiro relato de acariasis por Caparinia tripilis em ouriços Africanos, (Atelerix albiventris, na Costa Rica

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Andrés Moreira

2013-03-01

Full Text Available The African hedgehog is one of the newly imported exotic pets which have been observed with increasing regularity in veterinary clinics in Costa Rica. Despite their popularity, information about their diseases is scarce. Within skin diseases of hedgehogs, mange caused by Caparinia spp. is a common diagnosis in other countries. Two adult African hedgehogs, one male and one female, were brought to a private clinic in Heredia, Costa Rica, with chronic pruritic dermatitis, scabs, nearly complete loss of spines, lethargy, dehydration, and weight loss. During physical exam, deposits of dry seborrhea were taken and processed for diagnosis. Microscopic examination revealed psoroptid mites identified as Caparinia tripilis. This is the first report of the presence of Caparinia tripilis in Costa Rica and, to the authors' knowledge, the rest of Central America. O ouriço africano é um dos animais de estimação exótico, recém-importado que tem sido observado com maior regularidade nas clínicas veterinárias da Costa Rica. Apesar da sua popularidade, informações sobre suas doenças são escassas. Dentre as doenças de pele de ouriços, a sarna causada por Caparinia spp. é um diagnóstico comum nos outros países. Dois adultos ouriços africanos, um macho e uma fêmea, foram levados para uma clínica particular, em Heredia, Costa Rica, com a dermatite pruriginosa crônica, crostas, perda quase completa de espinhos, letargia, desidratação e perda de peso. Ao exame físico, os depósitos de seborreia seca foram retirados e processados para o diagnóstico. O exame microscópico revelou ácaros (psoroptidae identificados como Caparinia tripilis. Esse é o primeiro relato da presença de Caparinia tripilis na Costa Rica e, para conhecimento dos autores, o resto da América Central.

Two bifunctional enzymes from the marine protist Thraustochytrium roseum: biochemical characterization of wax ester synthase/acyl-CoA:diacylglycerol acyltransferase activity catalyzing wax ester and triacylglycerol synthesis.

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Zhang, Nannan; Mao, Zejing; Luo, Ling; Wan, Xia; Huang, Fenghong; Gong, Yangmin

2017-01-01

Triacylglycerols (TAGs) and wax esters (WEs) are important neutral lipids which serve as energy reservoir in some plants and microorganisms. In recent years, these biologically produced neutral lipids have been regarded as potential alternative energy sources for biofuel production because of the increased interest on developing renewable and environmentally benign alternatives for fossil fuels. In bacteria, the final step in TAG and WE biosynthetic pathway is catalyzed by wax ester synthase/acyl coenzyme A (acyl-CoA):diacylglycerol acyltransferase (WS/DGAT). This bifunctional WS/DGAT enzyme is also a key enzyme in biotechnological production of liquid WE via engineering of plants and microorganisms. To date, knowledge about this class of biologically and biotechnologically important enzymes is mainly from biochemical characterization of WS/DGATs from Arabidopsis, jojoba and some bacteria that can synthesize both TAGs and WEs intracellularly, whereas little is known about WS/DGATs from eukaryotic microorganisms. Here, we report the identification and characterization of two bifunctional WS/DGAT enzymes (designated TrWSD4 and TrWSD5) from the marine protist Thraustochytrium roseum . Both TrWSD4 and TrWSD5 comprise a WS-like acyl-CoA acyltransferase domain and the recombinant proteins purified from Escherichia coli Rosetta (DE3) have substantial WS and lower DGAT activity. They exhibit WS activity towards various-chain-length saturated and polyunsaturated acyl-CoAs and fatty alcohols ranging from C 10 to C 18 . TrWSD4 displays WS activity with the lowest K m value of 0.14 μM and the highest k cat / K m value of 1.46 × 10 5  M -1  s -1 for lauroyl-CoA (C 12:0 ) in the presence of 100 μM hexadecanol, while TrWSD5 exhibits WS activity with the lowest K m value of 0.96 μM and the highest k cat / K m value of 9.83 × 10 4  M -1  s -1 for decanoyl-CoA (C 10:0 ) under the same reaction condition. Both WS/DGAT enzymes have the highest WS activity at 37 and 47�

Discovery of a Novel Inhibitor of the Hedgehog Signaling Pathway through Cell-based Compound Discovery and Target Prediction.

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Kremer, Lea; Schultz-Fademrecht, Carsten; Baumann, Matthias; Habenberger, Peter; Choidas, Axel; Klebl, Bert; Kordes, Susanne; Schöler, Hans R; Sterneckert, Jared; Ziegler, Slava; Schneider, Gisbert; Waldmann, Herbert

2017-10-09

Cell-based assays enable monitoring of small-molecule bioactivity in a target-agnostic manner and help uncover new biological mechanisms. Subsequent identification and validation of the small-molecule targets, typically employing proteomics techniques, is very challenging and limited, in particular if the targets are membrane proteins. Herein, we demonstrate that the combination of cell-based bioactive-compound discovery with cheminformatic target prediction may provide an efficient approach to accelerate the process and render target identification and validation more efficient. Using a cell-based assay, we identified the pyrazolo-imidazole smoothib as a new inhibitor of hedgehog (Hh) signaling and an antagonist of the protein smoothened (SMO) with a novel chemotype. Smoothib targets the heptahelical bundle of SMO, prevents its ciliary localization, reduces the expression of Hh target genes, and suppresses the growth of Ptch +/- medulloblastoma cells. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Sonic Hedgehog switches on Wnt/planar cell polarity signaling in commissural axon growth cones by reducing levels of Shisa2

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Onishi, Keisuke

2017-01-01

Commissural axons switch on responsiveness to Wnt attraction during midline crossing and turn anteriorly only after exiting the floor plate. We report here that Sonic Hedgehog (Shh)-Smoothened signaling downregulates Shisa2, which inhibits the glycosylation and cell surface presentation of Frizzled3 in rodent commissural axon growth cones. Constitutive Shisa2 expression causes randomized turning of post-crossing commissural axons along the anterior–posterior (A–P) axis. Loss of Shisa2 led to precocious anterior turning of commissural axons before or during midline crossing. Post-crossing commissural axon turning is completely randomized along the A–P axis when Wntless, which is essential for Wnt secretion, is conditionally knocked out in the floor plate. This regulatory link between Shh and planar cell polarity (PCP) signaling may also occur in other developmental processes. PMID:28885142

Curcumin inhibits bladder cancer stem cells by suppressing Sonic Hedgehog pathway.

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Wang, Dengdian; Kong, Xiaochuan; Li, Yuan; Qian, Weiwei; Ma, Jiaxing; Wang, Daming; Yu, Dexin; Zhong, Caiyun

2017-11-04

Cancer stem cells (CSCs) is responsible for the recurrence of human cancers. Thus, targeting CSCs is considered to be a valid way for human cancer treatment. Curcumin is a major component of phytochemicals that exerts potent anticancer activities. However, the effect of curcumin on bladder cancer stem cells (BCSCs) remains to be elucidated. In this study, we investigated the mechanism of curcumin suppressing bladder cancer stem cells. In this study, UM-UC-3 and EJ cells were cultured in serum-free medium (SFM) to form cell spheres that was characterized as BCSCs. Then cell spheres were separately treated with different concentrations of curcumin and purmorphamine. Cell cycle analysis were used to determine the percentage of cells in different phases. Western blot and quantitative real-time PCR analysis were used to detect the expression of relative molecules. Immunofluorescence staining analysis were also utilized to measure the protein level of CD44. We found that CSC markers, including CD44, CD133, ALDH1-A1, OCT-4 and Nanog, were obviously highly expressed in cell spheres. Moreover, we observed that curcumin reduced the cell spheres formation, decreased the expression of CSC markers, suppressed cell proliferation and induced cell apoptosis. We also found that curcumin inhibited the activation of Shh pathway, while the inhibitory effects of curcumin on BCSCs could be weakened by upregulation of Sonic Hedgehog (Shh) pathway. Altogether, these data suggested that curcumin inhibited the activities of BCSCs through suppressing Shh pathway, which might be an effective chemopreventive agent for bladder cancer intervention. Copyright © 2017. Published by Elsevier Inc.

Sex-related difference in the inductions by perfluoro-octanoic acid of peroxisomal beta-oxidation, microsomal 1-acylglycerophosphocholine acyltransferase and cytosolic long-chain acyl-CoA hydrolase in rat liver.

Science.gov (United States)

Kawashima, Y; Uy-Yu, N; Kozuka, H

1989-01-01

Inductions by perfluoro-octanoic acid (PFOA) of hepatomegaly, peroxisomal beta-oxidation, microsomal 1-acylglycerophosphocholine acyltransferase and cytosolic long-chain acyl-CoA hydrolase were compared in liver between male and female rats. Marked inductions of these four parameters were seen concurrently in liver of male rats, whereas the inductions in liver of female rats were far less pronounced. The sex-related difference in the response of rat liver to PFOA was much more marked than that seen with p-chlorophenoxyisobutyric acid (clofibric acid) or 2,2'-(decamethylenedithio)diethanol (tiadenol). Hormonal manipulations revealed that this sex-related difference in the inductions is strongly dependent on sex hormones, namely that testosterone is necessary for the inductions, whereas oestradiol prevented the inductions by PFOA. PMID:2570571

Subcellular localization of Patched and Smoothened, the receptors for Sonic hedgehog signaling, in the hippocampal neuron.

Science.gov (United States)

Petralia, Ronald S; Schwartz, Catherine M; Wang, Ya-Xian; Mattson, Mark P; Yao, Pamela J

2011-12-15

Cumulative evidence suggests that, aside from patterning the embryonic neural tube, Sonic hedgehog (Shh) signaling plays important roles in the mature nervous system. In this study, we investigate the expression and localization of the Shh signaling receptors, Patched (Ptch) and Smoothened (Smo), in the hippocampal neurons of young and mature rats. Reverse transcriptase-polymerase chain reaction and immunoblotting analyses show that the expression of Ptch and Smo remains at a moderate level in young postnatal and adult brains. By using immunofluorescence light microscopy and immunoelectron microscopy, we examine the spatial distribution of Ptch and Smo within the hippocampal neurons. In young developing neurons, Ptch and Smo are present in the processes and are clustered at their growth cones. In mature neurons, Ptch and Smo are concentrated in dendrites, spines, and postsynaptic sites. Synaptic Ptch and Smo often co-exist with unusual structures-synaptic spinules and autophagosomes. Our results reveal the anatomical organization of the Shh receptors within both the young and the mature hippocampal neurons. Copyright © 2011 Wiley-Liss, Inc.

Chemical, computational and functional insights into the chemical stability of the Hedgehog pathway inhibitor GANT61.

Science.gov (United States)

Calcaterra, Andrea; Iovine, Valentina; Botta, Bruno; Quaglio, Deborah; D'Acquarica, Ilaria; Ciogli, Alessia; Iazzetti, Antonia; Alfonsi, Romina; Lospinoso Severini, Ludovica; Infante, Paola; Di Marcotullio, Lucia; Mori, Mattia; Ghirga, Francesca

2018-12-01

This work aims at elucidating the mechanism and kinetics of hydrolysis of GANT61, the first and most-widely used inhibitor of the Hedgehog (Hh) signalling pathway that targets Glioma-associated oncogene homologue (Gli) proteins, and at confirming the chemical nature of its bioactive form. GANT61 is poorly stable under physiological conditions and rapidly hydrolyses into an aldehyde species (GANT61-A), which is devoid of the biological activity against Hh signalling, and a diamine derivative (GANT61-D), which has shown inhibition of Gli-mediated transcription. Here, we combined chemical synthesis, NMR spectroscopy, analytical studies, molecular modelling and functional cell assays to characterise the GANT61 hydrolysis pathway. Our results show that GANT61-D is the bioactive form of GANT61 in NIH3T3 Shh-Light II cells and SuFu -/- mouse embryonic fibroblasts, and clarify the structural requirements for GANT61-D binding to Gli1. This study paves the way to the design of GANT61 derivatives with improved potency and chemical stability.

Novel function of lecithin-cholesterol acyltransferase. Hydrolysis of oxidized polar phospholipids generated during lipoprotein oxidation.

Science.gov (United States)

Goyal, J; Wang, K; Liu, M; Subbaiah, P V

1997-06-27

Although the major function of lecithin-cholesterol acyltransferase (LCAT) is cholesterol esterification, our previous studies showed that it can also hydrolyze platelet-activating factor (PAF). Because of the structural similarities between PAF and the truncated phosphatidylcholines (polar PCs) generated during lipoprotein oxidation, we investigated the possibility that LCAT may also hydrolyze polar PCs to lyso-PC during the oxidation of plasma. PAF acetylhydrolase (PAF-AH), which is known to hydrolyze polar PCs in human plasma, was completely inhibited by 0.2 mM p-aminoethyl benzenesulfonyl fluoride (Pefabloc), a new serine esterase inhibitor, which had no effect on LCAT at this concentration. On the other hand, 1 mM diisopropylfluorophosphate (DFP) completely inhibited LCAT but had no effect on PAF-AH. Polar PC accumulation during the oxidation of plasma increased by 44% in the presence of 0.2 mM Pefabloc and by 30% in the presence of 1 mM DFP. The formation of lyso-PC was concomitantly inhibited by both of the inhibitors. The combination of the two inhibitors resulted in the maximum accumulation of polar PCs, suggesting that both PAF-AH and LCAT are involved in their breakdown. Oxidation of chicken plasma, which has no PAF-AH activity, also resulted in the formation of lyso-PC from the hydrolysis of polar PC, which was inhibited by DFP. Polar PCs, either isolated from oxidized plasma or by oxidation of labeled synthetic PCs, were hydrolyzed by purified LCAT, which had no detectable PAF-AH activity. These results demonstrate a novel function for LCAT in the detoxification of polar PCs generated during lipoprotein oxidation, especially when the PAF-AH is absent or inactivated.

Sonic hedgehog initiates cochlear hair cell regeneration through downregulation of retinoblastoma protein

Energy Technology Data Exchange (ETDEWEB)

Lu, Na [Otology Skull Base Surgery Department, Hearing Research Institute, Eye and ENT Hospital of Shanghai Medical School, Fudan University, Shanghai 200031 (China); Department of Otolaryngology and Program in Neuroscience, Harvard Medical School and Eaton Peabody Laboratory, Massachusetts Eye and Ear Infirmary, Boston, MA 02114 (United States); Chen, Yan [Central Laboratory, Hearing Research Institute, Eye and ENT Hospital of Shanghai Medical School, Fudan University, Shanghai 200031 (China); Wang, Zhengmin [Otology Skull Base Surgery Department, Hearing Research Institute, Eye and ENT Hospital of Shanghai Medical School, Fudan University, Shanghai 200031 (China); Institute of Biomedical Sciences, Fudan University, Shanghai 200032 (China); Chen, Guoling [Otology Skull Base Surgery Department, Hearing Research Institute, Eye and ENT Hospital of Shanghai Medical School, Fudan University, Shanghai 200031 (China); Lin, Qin [Otology Skull Base Surgery Department, Hearing Research Institute, Eye and ENT Hospital of Shanghai Medical School, Fudan University, Shanghai 200031 (China); Department of Otolaryngology, First Affiliated Hospital of Fujian Medical University, Otolaryngology Institute of Fujian Province, Fuzhou (China); Chen, Zheng-Yi, E-mail: Zheng-yi_chen@meei.harvard.edu [Department of Otolaryngology and Program in Neuroscience, Harvard Medical School and Eaton Peabody Laboratory, Massachusetts Eye and Ear Infirmary, Boston, MA 02114 (United States); Li, Huawei, E-mail: hwli@shmu.edu.cn [Otology Skull Base Surgery Department, Hearing Research Institute, Eye and ENT Hospital of Shanghai Medical School, Fudan University, Shanghai 200031 (China); Institute of Biomedical Sciences, Fudan University, Shanghai 200032 (China)

2013-01-11

Highlights: Black-Right-Pointing-Pointer Shh activation in neonatal cochleae enhances sensory cell proliferation. Black-Right-Pointing-Pointer Proliferating supporting cells can transdifferentiate into hair cells. Black-Right-Pointing-Pointer Shh promotes proliferation by transiently modulating pRb activity. Black-Right-Pointing-Pointer Shh inhibits pRb by inhibiting transcription and increasing phosphorylation of pRb. -- Abstract: Cell cycle re-entry by cochlear supporting cells and/or hair cells is considered one of the best approaches for restoring hearing loss as a result of hair cell damage. To identify mechanisms that can be modulated to initiate cell cycle re-entry and hair cell regeneration, we studied the effect of activating the sonic hedgehog (Shh) pathway. We show that Shh signaling in postnatal rat cochleae damaged by neomycin leads to renewed proliferation of supporting cells and hair cells. Further, proliferating supporting cells are likely to transdifferentiate into hair cells. Shh treatment leads to inhibition of retinoblastoma protein (pRb) by increasing phosphorylated pRb and reducing retinoblastoma gene transcription. This results in upregulation of cyclins B1, D2, and D3, and CDK1. These results suggest that Shh signaling induces cell cycle re-entry in cochlear sensory epithelium and the production of new hair cells, in part by attenuating pRb function. This study provides an additional route to modulate pRb function with important implications in mammalian hair cell regeneration.