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Sample records for basic helix-loop-helix protein

  1. Phylogeny, Functional Annotation, and Protein Interaction Network Analyses of the Xenopus tropicalis Basic Helix-Loop-Helix Transcription Factors

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    Wuyi Liu

    2013-01-01

    Full Text Available The previous survey identified 70 basic helix-loop-helix (bHLH proteins, but it was proved to be incomplete, and the functional information and regulatory networks of frog bHLH transcription factors were not fully known. Therefore, we conducted an updated genome-wide survey in the Xenopus tropicalis genome project databases and identified 105 bHLH sequences. Among the retrieved 105 sequences, phylogenetic analyses revealed that 103 bHLH proteins belonged to 43 families or subfamilies with 46, 26, 11, 3, 15, and 4 members in the corresponding supergroups. Next, gene ontology (GO enrichment analyses showed 65 significant GO annotations of biological processes and molecular functions and KEGG pathways counted in frequency. To explore the functional pathways, regulatory gene networks, and/or related gene groups coding for Xenopus tropicalis bHLH proteins, the identified bHLH genes were put into the databases KOBAS and STRING to get the signaling information of pathways and protein interaction networks according to available public databases and known protein interactions. From the genome annotation and pathway analysis using KOBAS, we identified 16 pathways in the Xenopus tropicalis genome. From the STRING interaction analysis, 68 hub proteins were identified, and many hub proteins created a tight network or a functional module within the protein families.

  2. SREBP-2, a second basic-helix-loop-helix-leucine zipper protein that stimulates transcription by binding to a sterol regulatory element.

    OpenAIRE

    Hua, X; Yokoyama, C; Wu, J; Briggs, M R; Brown, M S; Goldstein, J L; Wang, X

    1993-01-01

    We report the cDNA cloning of SREBP-2, the second member of a family of basic-helix-loop-helix-leucine zipper (bHLH-Zip) transcription factors that recognize sterol regulatory element 1 (SRE-1). SRE-1, a conditional enhancer in the promoters for the low density lipoprotein receptor and 3-hydroxy-3-methylglutaryl-coenzyme A synthase genes, increases transcription in the absence of sterols and is inactivated when sterols accumulate. Human SREBP-2 contains 1141 amino acids and is 47% identical t...

  3. Sequence and function of basic helix-loop-helix proteins required for stomatal development in Arabidopsis are deeply conserved in land plants.

    Science.gov (United States)

    MacAlister, Cora A; Bergmann, Dominique C

    2011-01-01

    Stomata are a broadly conserved feature of land plants with a crucial role regulating transpiration and gas exchange between the plant and atmosphere. Stereotyped cell divisions within a specialized cell lineage of the epidermis generate stomata and define the pattern of their distribution. The behavior of the stomatal lineage varies in its detail among different plant groups, but general features include asymmetric cell divisions and an immediate precursor (the guard mother cell [GMC]) that divides symmetrically to form the pair of cells that will differentiate into the guard cells. In Arabidopsis, the closely related basic helix-loop-helix (bHLH) subgroup Ia transcription factors SPEECHLESS, MUTE, and FAMA promote asymmetric divisions, the acquisition of GMC identity and guard cell differentiation, respectively. Genome sequence data indicate that these key positive regulators of stomatal development are broadly conserved among land plants. While orthologies can be established among individual family members within the angiosperms, more distantly related groups contain subgroup Ia bHLHs of unclear affinity. We demonstrate group Ia members from the moss Physcomitrella patens can partially complement MUTE and FAMA and recapitulate gain of function phenotypes of group Ia genes in multiple steps in the stomatal lineage in Arabidopsis. Our data are consistent with a mechanism whereby a multifunctional transcription factor underwent duplication followed by specialization to provide the three (now nonoverlapping) functions of the angiosperm stomatal bHLHs. © 2011 Wiley Periodicals, Inc.

  4. PH4 of petunia is an R2R3-MYB protein that activates vacuolar acidification through interactions with Basic-Helix-Loop-Helix transcription factors of the anthocyanin pathway.

    NARCIS (Netherlands)

    Quattrocchio, F.M.; Verweij, C.W.; Spelt, C.E.; Mol, J.N.M.; Koes, R.E.

    2007-01-01

    The Petunia hybrids genes ANTHOCYANIN1 (AN1) and AN2 encode transcription factors with a basic-helix-loop-helix (BHLH) and a MYB domain, respectively, that are required for anthocyanin synthesis and acidification of the vacuole in petal cells. Mutation of PH4 results in a bluer flower color,

  5. A genome-wide survey on basic helix-loop-helix transcription factors in giant panda.

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    Chunwang Dang

    Full Text Available The giant panda (Ailuropoda melanoleuca is a critically endangered mammalian species. Studies on functions of regulatory proteins involved in developmental processes would facilitate understanding of specific behavior in giant panda. The basic helix-loop-helix (bHLH proteins play essential roles in a wide range of developmental processes in higher organisms. bHLH family members have been identified in over 20 organisms, including fruit fly, zebrafish, mouse and human. Our present study identified 107 bHLH family members being encoded in giant panda genome. Phylogenetic analyses revealed that they belong to 44 bHLH families with 46, 25, 15, 4, 11 and 3 members in group A, B, C, D, E and F, respectively, while the remaining 3 members were assigned into "orphan". Compared to mouse, the giant panda does not encode seven bHLH proteins namely Beta3a, Mesp2, Sclerax, S-Myc, Hes5 (or Hes6, EBF4 and Orphan 1. These results provide useful background information for future studies on structure and function of bHLH proteins in the regulation of giant panda development.

  6. A Classification of Basic Helix-Loop-Helix Transcription Factors of Soybean

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    Karen A. Hudson

    2015-01-01

    Full Text Available The complete genome sequence of soybean allows an unprecedented opportunity for the discovery of the genes controlling important traits. In particular, the potential functions of regulatory genes are a priority for analysis. The basic helix-loop-helix (bHLH family of transcription factors is known to be involved in controlling a wide range of systems critical for crop adaptation and quality, including photosynthesis, light signalling, pigment biosynthesis, and seed pod development. Using a hidden Markov model search algorithm, 319 genes with basic helix-loop-helix transcription factor domains were identified within the soybean genome sequence. These were classified with respect to their predicted DNA binding potential, intron/exon structure, and the phylogeny of the bHLH domain. Evidence is presented that the vast majority (281 of these 319 soybean bHLH genes are expressed at the mRNA level. Of these soybean bHLH genes, 67% were found to exist in two or more homeologous copies. This dataset provides a framework for future studies on bHLH gene function in soybean. The challenge for future research remains to define functions for the bHLH factors encoded in the soybean genome, which may allow greater flexibility for genetic selection of growth and environmental adaptation in this widely grown crop.

  7. Npas4, a novel helix-loop-helix PAS domain protein, is regulated in response to cerebral ischemia

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    Shamloo, Mehrdad; Soriano, Liza; von Schack, David

    2006-01-01

    Basic helix-loop-helix PAS domain proteins form a growing family of transcription factors. These proteins are involved in the process of adaptation to cellular stresses and environmental factors such as a change in oxygen concentration. We describe the identification and characterization of a rec...... lead to a decrease in the 200 kDa form and a simultaneous increase in the 100 kDa immunoreactivity. This could indicate a novel regulatory mechanism for activation and/or deactivation of this protein in response to ischemic brain injury....

  8. A single amino acid substitution in IIIf subfamily of basic helix-loop-helix transcription factor AtMYC1 leads to trichome and root hair patterning defects by abolishing its interaction with partner proteins in Arabidopsis.

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    Zhao, Hongtao; Wang, Xiaoxue; Zhu, Dandan; Cui, Sujuan; Li, Xia; Cao, Ying; Ma, Ligeng

    2012-04-20

    Plant trichomes and root hairs are powerful models for the study of cell fate determination. In Arabidopsis thaliana, trichome and root hair initiation requires a combination of three groups of proteins, including the WD40 repeat protein transparent TESTA GLABRA1 (TTG1), R2R3 repeat MYB protein GLABRA1 (GL1), or werewolf (WER) and the IIIf subfamily of basic helix-loop-helix (bHLH) protein GLABRA3 (GL3) or enhancer of GLABRA3 (EGL3). The bHLH component acts as a docking site for TTG1 and MYB proteins. Here, we isolated a mutant showing defects in trichome and root hair patterning that carried a point mutation (R173H) in AtMYC1 that encodes the fourth member of IIIf bHLH family protein. Genetic analysis revealed partial redundant yet distinct function between AtMYC1 and GL3/EGL3. GLABRA2 (GL2), an important transcription factor involved in trichome and root hair control, was down-regulated in Atmyc1 plants, suggesting the requirement of AtMYC1 for appropriate GL2 transcription. Like its homologs, AtMYC1 formed a complex with TTG1 and MYB proteins but did not dimerized. In addition, the interaction of AtMYC1 with MYB proteins and TTG1 was abrogated by the R173H substitution in Atmyc1-1. We found that this amino acid (Arg) is conserved in the AtMYC1 homologs GL3/EGL3 and that it is essential for their interaction with MYB proteins and for their proper functions. Our findings indicate that AtMYC1 is an important regulator of trichome and root hair initiation, and they reveal a novel amino acid necessary for protein-protein interactions and gene function in IIIf subfamily bHLH transcription factors.

  9. A Single Amino Acid Substitution in IIIf Subfamily of Basic Helix-Loop-Helix Transcription Factor AtMYC1 Leads to Trichome and Root Hair Patterning Defects by Abolishing Its Interaction with Partner Proteins in Arabidopsis*

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    Zhao, Hongtao; Wang, Xiaoxue; Zhu, Dandan; Cui, Sujuan; Li, Xia; Cao, Ying; Ma, Ligeng

    2012-01-01

    Plant trichomes and root hairs are powerful models for the study of cell fate determination. In Arabidopsis thaliana, trichome and root hair initiation requires a combination of three groups of proteins, including the WD40 repeat protein TRANSPARENT TESTA GLABRA1 (TTG1), R2R3 repeat MYB protein GLABRA1 (GL1), or WEREWOLF (WER) and the IIIf subfamily of basic helix-loop-helix (bHLH) protein GLABRA3 (GL3) or ENHANCER OF GLABRA3 (EGL3). The bHLH component acts as a docking site for TTG1 and MYB proteins. Here, we isolated a mutant showing defects in trichome and root hair patterning that carried a point mutation (R173H) in AtMYC1 that encodes the fourth member of IIIf bHLH family protein. Genetic analysis revealed partial redundant yet distinct function between AtMYC1 and GL3/EGL3. GLABRA2 (GL2), an important transcription factor involved in trichome and root hair control, was down-regulated in Atmyc1 plants, suggesting the requirement of AtMYC1 for appropriate GL2 transcription. Like its homologs, AtMYC1 formed a complex with TTG1 and MYB proteins but did not dimerized. In addition, the interaction of AtMYC1 with MYB proteins and TTG1 was abrogated by the R173H substitution in Atmyc1-1. We found that this amino acid (Arg) is conserved in the AtMYC1 homologs GL3/EGL3 and that it is essential for their interaction with MYB proteins and for their proper functions. Our findings indicate that AtMYC1 is an important regulator of trichome and root hair initiation, and they reveal a novel amino acid necessary for protein-protein interactions and gene function in IIIf subfamily bHLH transcription factors. PMID:22334670

  10. Basic helix-loop-helix transcription factors and epidermal cell fate determination in Arabidopsis.

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    Zhao, Hongtao; Li, Xia; Ma, Ligeng

    2012-12-01

    Cell fate determination is an important process in multicellular organisms. Plant epidermis is a readily-accessible, well-used model for the study of cell fate determination. Our knowledge of cell fate determination is growing steadily due to genetic and molecular analyses of root hairs, trichomes, and stomata, which are derived from the epidermal cells of roots and aerial tissues. Studies have shown that a large number of factors are involved in the establishment of these cell types, especially members of the basic helix-loop-helix (bHLH) superfamily, which is an important family of transcription factors. In this mini-review, we focus on the role of bHLH transcription factors in cell fate determination in Arabidopsis.

  11. A basic helix-loop-helix transcription factor DvIVS determines flower color intensity in cyanic dahlia cultivars.

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    Ohno, Sho; Deguchi, Ayumi; Hosokawa, Munetaka; Tatsuzawa, Fumi; Doi, Motoaki

    2013-08-01

    The study was aimed to identify the factors that regulate the intensity of flower color in cyanic dahlia (Dahlia variabilis), using fifteen cultivars with different color intensities in their petals. The cultivars were classified into three groups based on their flavonoid composition: ivory white cultivars with flavones; purple and pink cultivars with flavones and anthocyanins; and red cultivars with flavones, anthocyanins, and chalcones. Among the purple, pink, and ivory white cultivars, an inverse relationship was detected between lightness, which was used as an indicator for color intensity and anthocyanin content. A positive correlation was detected between anthocyanin contents and the expression of some structural genes in the anthocyanin synthesis pathway that are regulated by DvIVS, a basic helix-loop-helix transcription factor. A positive correlation between anthocyanin content and expression of DvIVS was also found. The promoter region of DvIVS was classified into three types, with cultivars carrying Type 1 promoter exhibited deep coloring, those carrying Type 2 and/or Type 3 exhibited pale coloring, and those carrying Type 1 and Type 2 and/or Type 3 exhibited medium coloring. The transcripts of the genes from these promoters encoded full-length predicted proteins. These results suggested that the genotype of the promoter region in DvIVS is one of the key factors determining the flower color intensity.

  12. Basic helix-loop-helix transcription factor TCF21 is a downstream target of the male sex determining gene SRY.

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    Ramji K Bhandari

    Full Text Available The cascade of molecular events involved in mammalian sex determination has been shown to involve the SRY gene, but specific downstream events have eluded researchers for decades. The current study identifies one of the first direct downstream targets of the male sex determining factor SRY as the basic-helix-loop-helix (bHLH transcription factor TCF21. SRY was found to bind to the Tcf21 promoter and activate gene expression. Mutagenesis of SRY/SOX9 response elements in the Tcf21 promoter eliminated the actions of SRY. SRY was found to directly associate with the Tcf21 promoter SRY/SOX9 response elements in vivo during fetal rat testis development. TCF21 was found to promote an in vitro sex reversal of embryonic ovarian cells to induce precursor Sertoli cell differentiation. TCF21 and SRY had similar effects on the in vitro sex reversal gonadal cell transcriptomes. Therefore, SRY acts directly on the Tcf21 promoter to in part initiate a cascade of events associated with Sertoli cell differentiation and embryonic testis development.

  13. Genome-wide identification of basic helix-loop-helix and NF-1 motifs underlying GR binding sites in male rat hippocampus

    DEFF Research Database (Denmark)

    Pooley, John R.; Flynn, Ben P.; Grøntved, Lars

    2017-01-01

    in hippocampal GR function. Our findings imply a dosedependent and context-independent action of GRs in the hippocampus. Alterations in the expression or activity of NF-1/basic helix-loop-helix factors may play an as yet undetermined role in glucocorticoid-related disease susceptibility and outcome by altering......Glucocorticoids regulate hippocampal function in part by modulating gene expression through the glucocorticoid receptor (GR). GR binding is highly cell type specific, directed to accessible chromatin regions established during tissue differentiation. Distinct classes of GR binding sites...... linked to structural and organizational roles, an absence of major tethering partners for GRs, and little or no evidence for binding at negative glucocorticoid response elements. A basic helix-loop-helix motif closely resembling a NeuroD1 or Olig2 binding site was found underlying a subset of GR binding...

  14. Phosphorylation of basic helix-loop-helix transcription factor Twist in development and disease.

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    Xue, Gongda; Hemmings, Brian A

    2012-02-01

    The transcription factor Twist plays vital roles during embryonic development through regulating/controlling cell migration. However, postnatally, in normal physiological settings, Twist is either not expressed or inactivated. Increasing evidence shows a strong correlation between Twist reactivation and both cancer progression and malignancy, where the transcriptional activities of Twist support cancer cells to disseminate from primary tumours and subsequently establish a secondary tumour growth in distant organs. However, it is largely unclear how this signalling programme is reactivated or what signalling pathways regulate its activity. The present review discusses recent advances in Twist regulation and activity, with a focus on phosphorylation-dependent Twist activity, potential upstream kinases and the contribution of these factors in transducing biological signals from upstream signalling complexes. The recent advances in these areas have shed new light on how phosphorylation-dependent regulation of the Twist proteins promotes or suppresses Twist activity, leading to differential regulation of Twist transcriptional targets and thereby influencing cell fate.

  15. Two basic-helix-loop-helix genes (MYC-146 and GL3) from Arabidopsis can activate anthocyanin biosynthesis in a white-flowered Matthiola incana mutant.

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    Ramsay, Nicola A; Walker, Amanda R; Mooney, Mark; Gray, John C

    2003-06-01

    Basic helix-loop-helix (bHLH) proteins, similar to mammalian Myc transcription factors, regulate the anthocyanin biosynthetic pathway in both monocots and dicots. Two Arabidopsis bHLH genes, GLABRA3 (GL3) and MYC-146, encode proteins that are similar throughout the predicted amino acid sequence to R and DELILA, which regulate anthocyanin production in maize and snapdragon, respectively. Northern blot analysis indicates that MYC-146 is most highly expressed in flower buds and flowers. Expression of a MYC-146 cDNA from the CaMV 35S promoter was unable to complement the anthocyanin deficiency in a ttg1 mutant of Arabidopsis and resulted in no obvious phenotypic change in Columbia plants. However, transient expression of GL3 and MYC-146 upon microprojectile bombardment of petals of a white-flowered mutant of Matthiola incana was able to complement anthocyanin deficiency. The lack of anthocyanin-deficient Arabidopsis mutants mapping to the locations of GL3 and MYC-146 suggests that the two bHLH proteins may be partially redundant and overlap in function.

  16. atonal- and achaete-scute-related genes in the annelid Platynereis dumerilii: insights into the evolution of neural basic-Helix-Loop-Helix genes

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    Arendt Detlev

    2008-06-01

    Full Text Available Abstract Background Functional studies in model organisms, such as vertebrates and Drosophila, have shown that basic Helix-loop-Helix (bHLH proteins have important roles in different steps of neurogenesis, from the acquisition of neural fate to the differentiation into specific neural cell types. However, these studies highlighted many differences in the expression and function of orthologous bHLH proteins during neural development between vertebrates and Drosophila. To understand how the functions of neural bHLH genes have evolved among bilaterians, we have performed a detailed study of bHLH genes during nervous system development in the polychaete annelid, Platynereis dumerilii, an organism which is evolutionary distant from both Drosophila and vertebrates. Results We have studied Platynereis orthologs of the most important vertebrate neural bHLH genes, i.e. achaete-scute, neurogenin, atonal, olig, and NeuroD genes, the latter two being genes absent of the Drosophila genome. We observed that all these genes have specific expression patterns during nervous system formation in Platynereis. Our data suggest that in Platynereis, like in vertebrates but unlike Drosophila, (i neurogenin is the main proneural gene for the formation of the trunk central nervous system, (ii achaete-scute and olig genes are involved in neural subtype specification in the central nervous system, in particular in the specification of the serotonergic phenotype. In addition, we found that the Platynereis NeuroD gene has a broad and early neuroectodermal expression, which is completely different from the neuronal expression of vertebrate NeuroD genes. Conclusion Our analysis suggests that the Platynereis bHLH genes have both proneural and neuronal specification functions, in a way more akin to the vertebrate situation than to that of Drosophila. We conclude that these features are ancestral to bilaterians and have been conserved in the vertebrates and annelids lineages, but

  17. The poplar basic helix-loop-helix transcription factor BEE3 – Like gene affects biomass production by enhancing proliferation of xylem cells in poplar

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    Noh, Seol Ah, E-mail: s6022029@korea.ac.kr; Choi, Young-Im, E-mail: yichoi99@forest.go.kr; Cho, Jin-Seong, E-mail: jinsung3932@gmail.com; Lee, Hyoshin, E-mail: hslee@forest.go.kr

    2015-06-19

    Brassinosteroids (BRs) play important roles in many aspects of plant growth and development, including regulation of vascular cambium activities and cell elongation. BR-induced BEE3 (brassinosteroid enhanced expression 3) is required for a proper BR response. Here, we identified a poplar (Populus alba × Populus glandulosa) BEE3-like gene, PagBEE3L, encoding a putative basic helix-loop-helix (bHLH)-type transcription factor. Expression of PagBEE3L was induced by brassinolide (BL). Transcripts of PagBEE3L were mainly detected in stems, with the internode having a low level of transcription and the node having a relatively higher level. The function of the PagBEE3L gene was investigated through phenotypic analyses with PagBEE3L-overexpressing (ox) transgenic lines. This work particularly focused on a potential role of PagBEE3L in stem growth and development of polar. The PagBEE3L-ox poplar showed thicker and longer stems than wild-type plants. The xylem cells from the stems of PagBEE3L-ox plants revealed remarkably enhanced proliferation, resulting in an earlier thickening growth than wild-type plants. Therefore, this work suggests that xylem development of poplar is accelerated in PagBEE3L-ox plants and PagBEE3L plays a role in stem growth by increasing the proliferation of xylem cells to promote the initial thickening growth of poplar stems. - Highlights: • We identify the BEE3-like gene form hybrid poplar (Populus alba × Populus glandulosa). • We examine effects of overexpression of PagBEE3L on growth in poplar. • We found that 35S:BEE3L transgenic plants showed more rapid growth than wild-type plants. • BEE3L protein plays an important role in the development of plant stem.

  18. The poplar basic helix-loop-helix transcription factor BEE3 – Like gene affects biomass production by enhancing proliferation of xylem cells in poplar

    International Nuclear Information System (INIS)

    Noh, Seol Ah; Choi, Young-Im; Cho, Jin-Seong; Lee, Hyoshin

    2015-01-01

    Brassinosteroids (BRs) play important roles in many aspects of plant growth and development, including regulation of vascular cambium activities and cell elongation. BR-induced BEE3 (brassinosteroid enhanced expression 3) is required for a proper BR response. Here, we identified a poplar (Populus alba × Populus glandulosa) BEE3-like gene, PagBEE3L, encoding a putative basic helix-loop-helix (bHLH)-type transcription factor. Expression of PagBEE3L was induced by brassinolide (BL). Transcripts of PagBEE3L were mainly detected in stems, with the internode having a low level of transcription and the node having a relatively higher level. The function of the PagBEE3L gene was investigated through phenotypic analyses with PagBEE3L-overexpressing (ox) transgenic lines. This work particularly focused on a potential role of PagBEE3L in stem growth and development of polar. The PagBEE3L-ox poplar showed thicker and longer stems than wild-type plants. The xylem cells from the stems of PagBEE3L-ox plants revealed remarkably enhanced proliferation, resulting in an earlier thickening growth than wild-type plants. Therefore, this work suggests that xylem development of poplar is accelerated in PagBEE3L-ox plants and PagBEE3L plays a role in stem growth by increasing the proliferation of xylem cells to promote the initial thickening growth of poplar stems. - Highlights: • We identify the BEE3-like gene form hybrid poplar (Populus alba × Populus glandulosa). • We examine effects of overexpression of PagBEE3L on growth in poplar. • We found that 35S:BEE3L transgenic plants showed more rapid growth than wild-type plants. • BEE3L protein plays an important role in the development of plant stem

  19. A genome-wide identification and analysis of the basic helix-loop-helix transcription factors in the ponerine ant, Harpegnathos saltator

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    Liu Ake

    2012-08-01

    Full Text Available Abstract Background The basic helix-loop-helix (bHLH transcription factors and their homologs form a superfamily that plays essential roles in transcriptional networks of multiple developmental processes. bHLH family members have been identified in over 20 organisms, including fruit fly, zebrafish, human and mouse. Result In this study, we conducted a genome-wide survey for bHLH sequences, and identified 57 bHLH sequences encoded in complete genome sequence of the ponerine ant, Harpegnathos saltator. Phylogenetic analysis of the bHLH domain sequences classified these genes into 38 bHLH families with 23, 14, 10, 1, 8 and 1 members in group A, B, C, D, E and F, respectively. The number of PabHLHs (ponerine ant bHLHs with introns is higher than many other insect species, and they are found to have introns with average lengths only inferior to those of pea aphid. In addition, two H. saltator bHLHs named PaCrp1 and PaSide locate on two separate contigs in the genome. Conclusions A putative full set of PabHLH genes is comparable with other insect species and genes encoding Oligo, MyoRb and Figα were not found in genomes of all insect species of which bHLH family members have been identified. Moreover, in-family phylogenetic analyses indicate that the PabHLH genes are more closely related with Apis mellifera than others. The present study will serve as a solid foundation for further investigations into the structure and function of bHLH proteins in the regulation of H. saltator development.

  20. Functional diversity of human basic helix-loop-helix transcription factor TCF4 isoforms generated by alternative 5' exon usage and splicing.

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    Mari Sepp

    Full Text Available BACKGROUND: Transcription factor 4 (TCF4 alias ITF2, E2-2, ME2 or SEF2 is a ubiquitous class A basic helix-loop-helix protein that binds to E-box DNA sequences (CANNTG. While involved in the development and functioning of many different cell types, recent studies point to important roles for TCF4 in the nervous system. Specifically, human TCF4 gene is implicated in susceptibility to schizophrenia and TCF4 haploinsufficiency is the cause of the Pitt-Hopkins mental retardation syndrome. However, the structure, expression and coding potential of the human TCF4 gene have not been described in detail. PRINCIPAL FINDINGS: In the present study we used human tissue samples to characterize human TCF4 gene structure and TCF4 expression at mRNA and protein level. We report that although widely expressed, human TCF4 mRNA expression is particularly high in the brain. We demonstrate that usage of numerous 5' exons of the human TCF4 gene potentially yields in TCF4 protein isoforms with 18 different N-termini. In addition, the diversity of isoforms is increased by alternative splicing of several internal exons. For functional characterization of TCF4 isoforms, we overexpressed individual isoforms in cultured human cells. Our analysis revealed that subcellular distribution of TCF4 isoforms is differentially regulated: Some isoforms contain a bipartite nuclear localization signal and are exclusively nuclear, whereas distribution of other isoforms relies on heterodimerization partners. Furthermore, the ability of different TCF4 isoforms to regulate E-box controlled reporter gene transcription is varied depending on whether one or both of the two TCF4 transcription activation domains are present in the protein. Both TCF4 activation domains are able to activate transcription independently, but act synergistically in combination. CONCLUSIONS: Altogether, in this study we have described the inter-tissue variability of TCF4 expression in human and provided evidence

  1. Ectopic expression of a basic helix-loop-helix gene transactivates parallel pathways of proanthocyanidin biosynthesis. structure, expression analysis, and genetic control of leucoanthocyanidin 4-reductase and anthocyanidin reductase genes in Lotus corniculatus.

    Science.gov (United States)

    Paolocci, Francesco; Robbins, Mark P; Madeo, Laura; Arcioni, Sergio; Martens, Stefan; Damiani, Francesco

    2007-01-01

    Proanthocyanidins (PAs) are plant secondary metabolites and are composed primarily of catechin and epicatechin units in higher plant species. Due to the ability of PAs to bind reversibly with plant proteins to improve digestion and reduce bloat, engineering this pathway in leaves is a major goal for forage breeders. Here, we report the cloning and expression analysis of anthocyanidin reductase (ANR) and leucoanthocyanidin 4-reductase (LAR), two genes encoding enzymes committed to epicatechin and catechin biosynthesis, respectively, in Lotus corniculatus. We show the presence of two LAR gene families (LAR1 and LAR2) and that the steady-state levels of ANR and LAR1 genes correlate with the levels of PAs in leaves of wild-type and transgenic plants. Interestingly, ANR and LAR1, but not LAR2, genes produced active proteins following heterologous expression in Escherichia coli and are affected by the same basic helix-loop-helix transcription factor that promotes PA accumulation in cells of palisade and spongy mesophyll. This study provides direct evidence that the same subclass of transcription factors can mediate the expression of the structural genes of both branches of PA biosynthesis.

  2. Reovirus FAST Proteins Drive Pore Formation and Syncytiogenesis Using a Novel Helix-Loop-Helix Fusion-Inducing Lipid Packing Sensor

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    Sarker, Muzaddid; de Antueno, Roberto; Langelaan, David N.; Parmar, Hiren B.; Shin, Kyungsoo; Rainey, Jan K.; Duncan, Roy

    2015-01-01

    Pore formation is the most energy-demanding step during virus-induced membrane fusion, where high curvature of the fusion pore rim increases the spacing between lipid headgroups, exposing the hydrophobic interior of the membrane to water. How protein fusogens breach this thermodynamic barrier to pore formation is unclear. We identified a novel fusion-inducing lipid packing sensor (FLiPS) in the cytosolic endodomain of the baboon reovirus p15 fusion-associated small transmembrane (FAST) protein that is essential for pore formation during cell-cell fusion and syncytiogenesis. NMR spectroscopy and mutational studies indicate the dependence of this FLiPS on a hydrophobic helix-loop-helix structure. Biochemical and biophysical assays reveal the p15 FLiPS preferentially partitions into membranes with high positive curvature, and this partitioning is impeded by bis-ANS, a small molecule that inserts into hydrophobic defects in membranes. Most notably, the p15 FLiPS can be functionally replaced by heterologous amphipathic lipid packing sensors (ALPS) but not by other membrane-interactive amphipathic helices. Furthermore, a previously unrecognized amphipathic helix in the cytosolic domain of the reptilian reovirus p14 FAST protein can functionally replace the p15 FLiPS, and is itself replaceable by a heterologous ALPS motif. Anchored near the cytoplasmic leaflet by the FAST protein transmembrane domain, the FLiPS is perfectly positioned to insert into hydrophobic defects that begin to appear in the highly curved rim of nascent fusion pores, thereby lowering the energy barrier to stable pore formation. PMID:26061049

  3. Reovirus FAST Proteins Drive Pore Formation and Syncytiogenesis Using a Novel Helix-Loop-Helix Fusion-Inducing Lipid Packing Sensor.

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    Jolene Read

    2015-06-01

    Full Text Available Pore formation is the most energy-demanding step during virus-induced membrane fusion, where high curvature of the fusion pore rim increases the spacing between lipid headgroups, exposing the hydrophobic interior of the membrane to water. How protein fusogens breach this thermodynamic barrier to pore formation is unclear. We identified a novel fusion-inducing lipid packing sensor (FLiPS in the cytosolic endodomain of the baboon reovirus p15 fusion-associated small transmembrane (FAST protein that is essential for pore formation during cell-cell fusion and syncytiogenesis. NMR spectroscopy and mutational studies indicate the dependence of this FLiPS on a hydrophobic helix-loop-helix structure. Biochemical and biophysical assays reveal the p15 FLiPS preferentially partitions into membranes with high positive curvature, and this partitioning is impeded by bis-ANS, a small molecule that inserts into hydrophobic defects in membranes. Most notably, the p15 FLiPS can be functionally replaced by heterologous amphipathic lipid packing sensors (ALPS but not by other membrane-interactive amphipathic helices. Furthermore, a previously unrecognized amphipathic helix in the cytosolic domain of the reptilian reovirus p14 FAST protein can functionally replace the p15 FLiPS, and is itself replaceable by a heterologous ALPS motif. Anchored near the cytoplasmic leaflet by the FAST protein transmembrane domain, the FLiPS is perfectly positioned to insert into hydrophobic defects that begin to appear in the highly curved rim of nascent fusion pores, thereby lowering the energy barrier to stable pore formation.

  4. The basic helix-loop-helix transcription factor Nex-1/Math-2 promotes neuronal survival of PC12 cells by modulating the dynamic expression of anti-apoptotic and cell cycle regulators.

    Science.gov (United States)

    Uittenbogaard, Martine; Chiaramello, Anne

    2005-02-01

    The basic helix-loop-helix transcription factor Nex1/Math-2 belongs to the NeuroD subfamily, which plays a critical role during neuronal differentiation and maintenance of the differentiated state. Previously, we demonstrated that Nex1 is a key regulatory component of the nerve growth factor (NGF) pathway. Further supporting this hypothesis, this study shows that Nex1 has survival-inducing properties similar to NGF, as Nex1-overexpressing PC12 cells survive in the absence of trophic factors. We dissected the molecular mechanism by which Nex1 confers neuroprotection upon serum removal and found that constitutive expression of Nex1 maintained the expression of specific G1 phase cyclin-dependent kinase inhibitors and concomitantly induced a dynamic expression profile of key anti-apoptotic regulators. This study provides the first evidence of the underlying mechanism by which a member of the NeuroD-subfamily promotes an active anti-apoptotic program essential to the survival of neurons. Our results suggest that the survival program may be viewed as an integral component of the intrinsic programming of the differentiated state.

  5. The Neurogenic Basic Helix-Loop-Helix Transcription Factor NeuroD6 Enhances Mitochondrial Biogenesis and Bioenergetics to Confer Tolerance of Neuronal PC12-NeuroD6 Cells to the Mitochondrial Stressor Rotenone

    Science.gov (United States)

    Baxter, Kristin Kathleen; Uittenbogaard, Martine; Chiaramello, Anne

    2012-01-01

    The fundamental question of how and which neuronal specific transcription factors tailor mitochondrial bioenergetics to the need of developing neuronal cells has remained largely unexplored. In this study, we report that the neurogenic basic helix-loop-helix transcription factor NeuroD6 possesses mitochondrial biogenic properties by amplifying the mitochondrial DNA content and TFAM expression levels, a key regulator for mitochondrial biogenesis. NeuroD6-mediated increase in mitochondrial biogenesis in the neuronal progenitor-like PC12-NEUROD6 cells is concomitant with enhanced mitochondrial bioenergetic functions, including increased expression levels of specific subunits of respiratory complexes of the electron transport chain, elevated mitochondrial membrane potential and ATP levels produced by oxidative phosphorylation. Thus, NeuroD6 augments the bioenergetic capacity of PC12-NEUROD6 cells to generate an energetic reserve, which confers tolerance to the mitochondrial stressor, rotenone. We found that NeuroD6 induces an adaptive bioenergetic response throughout rotenone treatment involving maintenance of the mitochondrial membrane potential and ATP levels in conjunction with preservation of the actin network. In conclusion, our results support the concept that NeuroD6 plays an integrative role in regulating and coordinating the onset of neuronal differentiation with acquisition of adequate mitochondrial mass and energetic capacity to ensure energy demanding events, such as cytoskeletal remodeling, plasmalemmal expansion, and growth cone formation. PMID:22814253

  6. The Neurogenic Basic Helix-Loop-Helix Transcription Factor NeuroD6 Concomitantly Increases Mitochondrial mass and Regulates Cytoskeletal Organization in the Early Stages of Neuronal Differentiation

    Directory of Open Access Journals (Sweden)

    Kristin Kathleen Baxter

    2009-08-01

    Full Text Available Mitochondria play a central role during neurogenesis by providing energy in the form of ATP for cytoskeletal remodelling, outgrowth of neuronal processes, growth cone activity and synaptic activity. However, the fundamental question of how differentiating neurons control mitochondrial biogenesis remains vastly unexplored. Since our previous studies have shown that the neurogenic bHLH (basic helix–loop–helix transcription factor NeuroD6 is sufficient to induce differentiation of the neuronal progenitor-like PC12 cells and that it triggers expression of mitochondrial-related genes, we investigated whether NeuroD6 could modulate the mitochondrial biomass using our PC12-ND6 cellular paradigm. Using a combination of flow cytometry, confocal microscopy and mitochondrial fractionation, we demonstrate that NeuroD6 stimulates maximal mitochondrial mass at the lamellipodia stage, thus preceding axonal growth. NeuroD6 triggers remodelling of the actin and microtubule networks in conjunction with increased expression of the motor protein KIF5B, thus promoting mitochondrial movement in developing neurites with accumulation in growth cones. Maintenance of the NeuroD6-induced mitochondrial mass requires an intact cytoskeletal network, as its disruption severely reduces mitochondrial mass. The present study provides the first evidence that NeuroD6 plays an integrative role in co-ordinating increase in mitochondrial mass with cytoskeletal remodelling, suggestive of a role of this transcription factor as a co-regulator of neuronal differentiation and energy metabolism.

  7. The neurogenic basic helix-loop-helix transcription factor NeuroD6 enhances mitochondrial biogenesis and bioenergetics to confer tolerance of neuronal PC12-NeuroD6 cells to the mitochondrial stressor rotenone

    Energy Technology Data Exchange (ETDEWEB)

    Baxter, Kristin Kathleen; Uittenbogaard, Martine [Department of Anatomy and Regenerative Biology, George Washington University Medical Center, Washington, DC (United States); Chiaramello, Anne, E-mail: achiaram@gwu.edu [Department of Anatomy and Regenerative Biology, George Washington University Medical Center, Washington, DC (United States)

    2012-10-15

    The fundamental question of how and which neuronal specific transcription factors tailor mitochondrial biogenesis and bioenergetics to the need of developing neuronal cells has remained largely unexplored. In this study, we report that the neurogenic basic helix-loop-helix transcription factor NeuroD6 possesses mitochondrial biogenic properties by amplifying the mitochondrial DNA content and TFAM expression levels, a key regulator for mitochondrial biogenesis. NeuroD6-mediated increase in mitochondrial biogenesis in the neuronal progenitor-like PC12-NEUROD6 cells is concomitant with enhanced mitochondrial bioenergetic functions, including increased expression levels of specific subunits of respiratory complexes of the electron transport chain, elevated mitochondrial membrane potential and ATP levels produced by oxidative phosphorylation. Thus, NeuroD6 augments the bioenergetic capacity of PC12-NEUROD6 cells to generate an energetic reserve, which confers tolerance to the mitochondrial stressor, rotenone. We found that NeuroD6 induces an adaptive bioenergetic response throughout rotenone treatment involving maintenance of the mitochondrial membrane potential and ATP levels in conjunction with preservation of the actin network. In conclusion, our results support the concept that NeuroD6 plays an integrative role in regulating and coordinating the onset of neuronal differentiation with acquisition of adequate mitochondrial mass and energetic capacity to ensure energy demanding events, such as cytoskeletal remodeling, plasmalemmal expansion, and growth cone formation. -- Highlights: Black-Right-Pointing-Pointer NeuroD6 induces mitochondrial biogenesis in neuroprogenitor-like cells. Black-Right-Pointing-Pointer NeuroD6 augments the bioenergetic reserve of the neuronal PC12-NeuroD6 cells. Black-Right-Pointing-Pointer NeuroD6 increases the mitochondrial membrane potential and ATP levels. Black-Right-Pointing-Pointer NeuroD6 confers tolerance to rotenone via an adaptive

  8. Functional characterization of a basic helix-loop-helix (bHLH) transcription factor GhDEL65 from cotton (Gossypium hirsutum).

    Science.gov (United States)

    Shangguan, Xiao-Xia; Yang, Chang-Qing; Zhang, Xiu-Fang; Wang, Ling-Jian

    2016-10-01

    Cotton fiber is proposed to share some similarity with the Arabidopsis thaliana leaf trichome, which is regulated by the MYB-bHLH-WD40 transcription complex. Although several MYB transcription factors and WD40 family proteins in cotton have been characterized, little is known about the role of bHLH family proteins in cotton. Here, we report that GhDEL65, a bHLH protein from cotton (Gossypium hirsutum), is a functional homologue of Arabidopsis GLABRA3 (GL3) and ENHANCER OF GLABRA3 (EGL3) in regulating trichome development. Transcripts of GhDEL65 were detected in 0 ∼ 1 days post-anthesis (DPA) ovules and abundant in 3-DPA fibers, implying that GhDEL65 may act in early fiber development. Ectopic expression of GhDEL65 in Arabidopsis gl3 egl3 double mutant partly rescued the trichome development, and constitutive expression of GhDEL65 in wild-type plants led to increased trichome density on rosette leaves and stems, mainly by activating the transcription of two key positive regulators of trichome development, GLABRA1 (GL1) and GLABRA2 (GL2), and suppressed the expression of a R3 single-repeat MYB factor TRIPTYCHON (TRY). GhDEL65 could interact with cotton R2R3 MYB transcription factors GhMYB2 and GhMYB3, as well as the WD40 protein GhTTG3, suggesting that the MYB-bHLH-WD40 protein complex also exists in cotton fiber cell, though its function in cotton fiber development awaits further investigation. © 2016 Scandinavian Plant Physiology Society.

  9. C-Myc Protein-Protein and Protein-DNA Interactions: Targets for Therapeutic Intervention

    National Research Council Canada - National Science Library

    Blackwell, T

    1997-01-01

    Members of the basic-helix-loop-helix (bHLH) family of transcription factors are involved in various aspects of cell growth and differentiation, and the bHLH protein c-Myc has been implicated in breast cancer...

  10. Basic helix-loop-helix proteins E2A and HEB induce immature T-cell receptor rearrangements in nonlymphoid cells

    NARCIS (Netherlands)

    A.W. Langerak (Anton); I.L. Wolvers-Tettero; E.J. van Gastel-Mol (Ellen); M.E. Oud; J.J.M. van Dongen (Jacques)

    2001-01-01

    textabstractT-cell receptor (TCR) gene rearrangements are mediated via V(D)J recombination, which is strictly regulated during lymphoid differentiation, most probably through the action of specific transcription factors. Investigated was whether cotransfection of RAG1 and

  11. Overexpression of OrbHLH001, a putative helix-loop-helix transcription factor, causes increased expression of AKT1 and maintains ionic balance under salt stress in rice.

    Science.gov (United States)

    Chen, Yuan; Li, Fei; Ma, Yan; Chong, Kang; Xu, Yunyuan

    2013-01-01

    The basic helix-loop-helix family of proteins, which function as transcription factors, have been intensively studied in plants and animals. However, the molecular mechanism of these factors contributing to stress tolerance is unknown. Here, we report on the overexpression of OrbHLH001 from Dongxiang wild rice (Oryza rufipogon) conferring salt tolerance in transgenic rice plants. The expression of OrbHLH001 was tissue specific, mainly in phloem tissues throughout the plant. Ion assay with the scanning ion-selective electrode technique showed that NaCl stress has a greater influence on Na(+) efflux and K(+) influx in OrbHLH001-overexpressed plants than the wild type. OrbHLH001 protein can induce the expression of OsAKT1 to regulate the Na(+)/K(+) ratio in OrbHLH001-overexpressed plants by specifically binding to an E-box motif in the promoter region of OsAKT1. The mechanism may have potential use in rice molecular breeding. Copyright © 2012 Elsevier GmbH. All rights reserved.

  12. A dominant-negative mutant of Max that inhibits sequence-specific DNA binding by Myc proteins

    NARCIS (Netherlands)

    Billaud, Marc; Isselbacher, Kurt J.; Bernards, R.A.

    1993-01-01

    Myc proteins are basic helix-loop-helix/ leucine-zipper proteins that bind to specific DNA sequences. In vivo, Myc proteins have been found associated with Max, another basic helix4oop-helix/leucine-zipper protein. However, it is not known to what extent the dimerization of Myc with Max is

  13. A Radish Basic Helix-Loop-Helix Transcription Factor, RsTT8 Acts a Positive Regulator for Anthocyanin Biosynthesis

    Directory of Open Access Journals (Sweden)

    Sun-Hyung Lim

    2017-11-01

    Full Text Available The MYB-bHLH-WDR (MBW complex activates anthocyanin biosynthesis through the transcriptional regulation. RsMYB1 has been identified as a key player in anthocyanin biosynthesis in red radish (Raphanus sativus L., but its partner bHLH transcription factor (TF remains to be determined. In this study, we isolated a bHLH TF gene from red radish. Phylogenetic analysis indicated that this gene belongs to the TT8 clade of the IIIF subgroup of bHLH TFs, and we thus designated this gene RsTT8. Subcellular localization analysis showed that RsTT8-sGFP was localized to the nuclei of Arabidopsis thaliana protoplasts harboring the RsTT8-sGFP construct. We evaluated anthocyanin biosynthesis and RsTT8 expression levels in three radish varieties (N, C, and D that display different red phenotypes in the leaves, root flesh, and root skins. The root flesh of the C variety and the leaves and skins of the D variety exhibit intense red pigmentation; in these tissues, RsTT8 expression showed totally positive association with the expression of RsMYB1 TF and of five of eight tested anthocyanin biosynthesis genes (i.e., RsCHS, RsCHI, RsF3H, RsDFR, and RsANS. Heterologous co-expression of both RsTT8 and RsMYB1 in tobacco leaves dramatically increased the expression of endogenous anthocyanin biosynthesis genes and anthocyanin accumulation. Furthermore, a yeast two-hybrid assay showed that RsTT8 interacts with RsMYB1 at the MYB-interacting region (MIR, and a transient transactivation assay indicated that RsTT8 activates the RsCHS and RsDFR promoters when co-expressed with RsMYB1. Complementation of the Arabidopsis tt8-1 mutant, which lacks red pigmentation in the leaves and seeds, with RsTT8 restored red pigmentation, and resulted in high anthocyanin and proanthocyanidin contents in the leaves and seeds, respectively. Together, these results show that RsTT8 functions as a regulatory partner with RsMYB1 during anthocyanin biosynthesis.

  14. Sumoylation of the basic helix-loop-helix transcription factor sharp-1 regulates recruitment of the histone methyltransferase G9a and function in myogenesis.

    Science.gov (United States)

    Wang, Yaju; Shankar, Shilpa Rani; Kher, Devaki; Ling, Belinda Mei Tze; Taneja, Reshma

    2013-06-14

    Sumoylation is an important post-translational modification that alters the activity of many transcription factors. However, the mechanisms that link sumoylation to alterations in chromatin structure, which culminate in tissue specific gene expression, are not fully understood. In this study, we demonstrate that SUMO modification of the transcription factor Sharp-1 is required for its full transcriptional repression activity and function as an inhibitor of skeletal muscle differentiation. Sharp-1 is modified by sumoylation at two conserved lysine residues 240 and 255. Mutation of these SUMO acceptor sites in Sharp-1 does not impact its subcellular localization but attenuates its ability to act as a transcriptional repressor and inhibit myogenic differentiation. Consistently, co-expression of the SUMO protease SENP1 with wild type Sharp-1 abrogates Sharp-1-dependent inhibition of myogenesis. Interestingly, sumoylation acts as a signal for recruitment of the co-repressor G9a. Thus, enrichment of G9a, and histone H3 lysine 9 dimethylation (H3K9me2), a signature of G9a activity, is dramatically reduced at muscle promoters in cells expressing sumoylation-defective Sharp-1. Our findings demonstrate how sumoylation of Sharp-1 exerts an impact on chromatin structure and transcriptional repression of muscle gene expression through recruitment of G9a.

  15. Sumoylation of the Basic Helix-Loop-Helix Transcription Factor Sharp-1 Regulates Recruitment of the Histone Methyltransferase G9a and Function in Myogenesis*

    Science.gov (United States)

    Wang, Yaju; Shankar, Shilpa Rani; Kher, Devaki; Ling, Belinda Mei Tze; Taneja, Reshma

    2013-01-01

    Sumoylation is an important post-translational modification that alters the activity of many transcription factors. However, the mechanisms that link sumoylation to alterations in chromatin structure, which culminate in tissue specific gene expression, are not fully understood. In this study, we demonstrate that SUMO modification of the transcription factor Sharp-1 is required for its full transcriptional repression activity and function as an inhibitor of skeletal muscle differentiation. Sharp-1 is modified by sumoylation at two conserved lysine residues 240 and 255. Mutation of these SUMO acceptor sites in Sharp-1 does not impact its subcellular localization but attenuates its ability to act as a transcriptional repressor and inhibit myogenic differentiation. Consistently, co-expression of the SUMO protease SENP1 with wild type Sharp-1 abrogates Sharp-1-dependent inhibition of myogenesis. Interestingly, sumoylation acts as a signal for recruitment of the co-repressor G9a. Thus, enrichment of G9a, and histone H3 lysine 9 dimethylation (H3K9me2), a signature of G9a activity, is dramatically reduced at muscle promoters in cells expressing sumoylation-defective Sharp-1. Our findings demonstrate how sumoylation of Sharp-1 exerts an impact on chromatin structure and transcriptional repression of muscle gene expression through recruitment of G9a. PMID:23637228

  16. The Drosophila homologue of vertebrate myogenic-determination genes encodes a transiently expressed nuclear protein marking primary myogenic cells.

    OpenAIRE

    Paterson, B M; Walldorf, U; Eldridge, J; Dübendorfer, A; Frasch, M; Gehring, W J

    1991-01-01

    We have isolated a cDNA clone, called Dmyd for Drosophila myogenic-determination gene, that encodes a protein with structural and functional characteristics similar to the members of the vertebrate MyoD family. Dmyd clone encodes a polypeptide of 332 amino acids with 82% identity to MyoD in the 41 amino acids of the putative helix-loop-helix region and 100% identity in the 13 amino acids of the basic domain proposed to contain the essential recognition code for muscle-specific gene activation...

  17. PH4 of petunia is an R2R3-MYB protein that activates vacuolar acidification through interactions with Basic-Helix-Loop transcription factors of the anthocyanin pathway.

    NARCIS (Netherlands)

    Quattrocchio, F.M.; Verweij, C.W.; Kroon, A.R.; Spelt, C.E.; Mol, J.N.M.; Koes, R.E.

    2006-01-01

    The Petunia hybrids genes ANTHOCYANIN1 (AN1) and AN2 encode transcription factors with a basic-helix-loop-helix (BHLH) and a MYB domain, respectively, that are required for anthocyanin synthesis and acidification of the vacuole in petal cells. Mutation of PH4 results in a bluer flower color,

  18. Marked induction of the helix-loop-helix protein Id3 promotes the gammadelta T cell fate and renders their functional maturation Notch independent

    DEFF Research Database (Denmark)

    Lauritsen, Jens Peter Holst; Wong, Gladys W; Lee, Sang-Yun

    2009-01-01

    )-inhibitor of DNA binding 3 (Id3) pathway plays a defining role in this process. In particular, Id3 expression served to regulate adoption of the gammadelta fate. Moreover, Id3 was both necessary and sufficient to enable gammadelta-lineage cells to differentiate independently of Notch signaling and become competent...

  19. SREBP-1 dimerization specificity maps to both the helix-loop-helix and leucine zipper domains: use of a dominant negative

    DEFF Research Database (Denmark)

    Rishi, Vikas; Gal, Jozsef; Krylov, Dmitry

    2004-01-01

    -HLH-ZIP proteins MAX, USF, or MITF, even at 100 molar eq. Chimeric proteins containing the HLH domain of SREBP-1 and the leucine zipper from either MAX, USF, or MITF indicate that both the HLH and leucine zipper regions of SREBP-1 contribute to its dimerization specificity. Transient co-transfection studies...

  20. Experiment list: SRX190201 [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available imers between TCF3 and tissue-specific basic helix-loop-helix (bHLH) proteins play major roles...antibody targetdescription=Heterodimers between TCF3 and tissue-specific basic helix-loop-helix (bHLH) proteins play major roles

  1. Expression of Id proteins increases in astrocytes in the hippocampus of epileptic rats

    NARCIS (Netherlands)

    Aronica, E.; Vandeputte, D. A.; van Vliet, E. A.; Lopes da Silva, F. H.; Troost, D.; Gorter, J. A.

    2001-01-01

    Reactive gliosis is a prominent morphological feature of temporal lobe epilepsy. The molecular mechanisms underlying glial cell activation remain unclear. We examined expression of Id1-3 protein, a family of helix--loop--helix proteins involved in the regulation of cell proliferation and

  2. Proteasome-dependent degradation of transcription factor activating enhancer-binding protein 4 (TFAP4) controls mitotic division

    NARCIS (Netherlands)

    D'Annibale, Sara; Kim, Jihoon; Magliozzi, Roberto; Low, Teck Yew; Mohammed, Shabaz; Heck, Albert J R; Guardavaccaro, Daniele

    2014-01-01

    TFAP4, a basic helix-loop-helix transcription factor that regulates the expression of a multitude of genes involved in the regulation of cellular proliferation, stemness, and epithelial-mesenchymal transition, is up-regulated in colorectal cancer and a number of other human malignancies. We have

  3. Type I bHLH Proteins Daughterless and Tcf4 Restrict Neurite Branching and Synapse Formation by Repressing Neurexin in Postmitotic Neurons

    Directory of Open Access Journals (Sweden)

    Mitchell D’Rozario

    2016-04-01

    Full Text Available Proneural proteins of the class I/II basic-helix-loop-helix (bHLH family are highly conserved transcription factors. Class I bHLH proteins are expressed in a broad number of tissues during development, whereas class II bHLH protein expression is more tissue restricted. Our understanding of the function of class I/II bHLH transcription factors in both invertebrate and vertebrate neurobiology is largely focused on their function as regulators of neurogenesis. Here, we show that the class I bHLH proteins Daughterless and Tcf4 are expressed in postmitotic neurons in Drosophila melanogaster and mice, respectively, where they function to restrict neurite branching and synapse formation. Our data indicate that Daughterless performs this function in part by restricting the expression of the cell adhesion molecule Neurexin. This suggests a role for these proteins outside of their established roles in neurogenesis.

  4. Breaking the silence: three bHLH proteins direct cell-fate decisions during stomatal development.

    Science.gov (United States)

    Pillitteri, Lynn Jo; Torii, Keiko U

    2007-09-01

    Stomata are microscopic pores on the surface of land plants used for gas and water vapor exchange. A pair of highly specialized guard cells surround the pore and adjust pore size. Studies in Arabidopsis have revealed that cell-cell communication is essential to coordinate the asymmetric cell divisions required for proper stomatal patterning. Initial research in this area identified signaling molecules that negatively regulate stomatal differentiation. However, genes promoting cell-fate transition leading to mature guard cells remained elusive. Now, three closely related basic helix-loop-helix (bHLH) proteins, SPEECHLESS, MUTE and FAMA have been identified as positive regulators that direct three consecutive cell-fate decisions during stomatal development. The identification of these genes opens a new direction to investigate the evolution of stomatal development and the conserved functions of bHLH proteins in cell type differentiation adopted by plants and animals.

  5. Direct Detection of Transcription Factors in Cotyledons during Seedling Development Using Sensitive Silicon-Substrate Photonic Crystal Protein Arrays1[OPEN

    Science.gov (United States)

    Jones, Sarah I.; Tan, Yafang; Shamimuzzaman, Md; George, Sherine; Cunningham, Brian T.; Vodkin, Lila

    2015-01-01

    Transcription factors control important gene networks, altering the expression of a wide variety of genes, including those of agronomic importance, despite often being expressed at low levels. Detecting transcription factor proteins is difficult, because current high-throughput methods may not be sensitive enough. One-dimensional, silicon-substrate photonic crystal (PC) arrays provide an alternative substrate for printing multiplexed protein microarrays that have greater sensitivity through an increased signal-to-noise ratio of the fluorescent signal compared with performing the same assay upon a traditional aminosilanized glass surface. As a model system to test proof of concept of the silicon-substrate PC arrays to directly detect rare proteins in crude plant extracts, we selected representatives of four different transcription factor families (zinc finger GATA, basic helix-loop-helix, BTF3/NAC [for basic transcription factor of the NAC family], and YABBY) that have increasing transcript levels during the stages of seedling cotyledon development. Antibodies to synthetic peptides representing the transcription factors were printed on both glass slides and silicon-substrate PC slides along with antibodies to abundant cotyledon proteins, seed lectin, and Kunitz trypsin inhibitor. The silicon-substrate PC arrays proved more sensitive than those performed on glass slides, detecting rare proteins that were below background on the glass slides. The zinc finger transcription factor was detected on the PC arrays in crude extracts of all stages of the seedling cotyledons, whereas YABBY seemed to be at the lower limit of their sensitivity. Interestingly, the basic helix-loop-helix and NAC proteins showed developmental profiles consistent with their transcript patterns, indicating proof of concept for detecting these low-abundance proteins in crude extracts. PMID:25635113

  6. Responses of a triple mutant defective in three iron deficiency-induced Basic Helix-Loop-Helix genes of the subgroup Ib(2 to iron deficiency and salicylic acid.

    Directory of Open Access Journals (Sweden)

    Felix Maurer

    Full Text Available Plants are sessile organisms that adapt to external stress by inducing molecular and physiological responses that serve to better cope with the adverse growth condition. Upon low supply of the micronutrient iron, plants actively increase the acquisition of soil iron into the root and its mobilization from internal stores. The subgroup Ib(2 BHLH genes function as regulators in this response, however their concrete functions are not fully understood. Here, we analyzed a triple loss of function mutant of BHLH39, BHLH100 and BHLH101 (3xbhlh mutant. We found that this mutant did not have any iron uptake phenotype if iron was provided. However, under iron deficiency the mutant displayed a more severe leaf chlorosis than the wild type. Microarray-based transcriptome analysis revealed that this mutant phenotype resulted in the mis-regulation of 198 genes, out of which only 15% were associated with iron deficiency regulation itself. A detailed analysis revealed potential targets of the bHLH transcription factors as well as genes reflecting an exaggerated iron deficiency response phenotype. Since the BHLH genes of this subgroup have been brought into the context of the plant hormone salicylic acid, we investigated whether the 3xbhlh mutant might have been affected by this plant signaling molecule. Although a very high number of genes responded to SA, also in a differential manner between mutant and wild type, we did not find any indication for an association of the BHLH gene functions in SA responses upon iron deficiency. In summary, our study indicates that the bHLH subgroup Ib(2 transcription factors do not only act in iron acquisition into roots but in other aspects of the adaptation to iron deficiency in roots and leaves.

  7. The Intellectual Disability and Schizophrenia Associated Transcription Factor TCF4 Is Regulated by Neuronal Activity and Protein Kinase A.

    Science.gov (United States)

    Sepp, Mari; Vihma, Hanna; Nurm, Kaja; Urb, Mari; Page, Stephanie Cerceo; Roots, Kaisa; Hark, Anu; Maher, Brady J; Pruunsild, Priit; Timmusk, Tõnis

    2017-10-25

    Transcription factor 4 (TCF4 also known as ITF2 or E2-2) is a basic helix-loop-helix (bHLH) protein associated with Pitt-Hopkins syndrome, intellectual disability, and schizophrenia (SCZ). Here, we show that TCF4-dependent transcription in cortical neurons cultured from embryonic rats of both sexes is induced by neuronal activity via soluble adenylyl cyclase and protein kinase A (PKA) signaling. PKA phosphorylates TCF4 directly and a PKA phosphorylation site in TCF4 is necessary for its transcriptional activity in cultured neurons and in the developing brain in vivo We also demonstrate that Gadd45g (growth arrest and DNA damage inducible gamma) is a direct target of neuronal-activity-induced, TCF4-dependent transcriptional regulation and that TCF4 missense variations identified in SCZ patients alter the transcriptional activity of TCF4 in neurons. This study identifies a new role for TCF4 as a neuronal-activity-regulated transcription factor, offering a novel perspective on the association of TCF4 with cognitive disorders. SIGNIFICANCE STATEMENT The importance of the basic helix-loop-helix transcription factor transcription factor 4 (TCF4) in the nervous system is underlined by its association with common and rare cognitive disorders. In the current study, we show that TCF4-controlled transcription in primary cortical neurons is induced by neuronal activity and protein kinase A. Our results support the hypotheses that dysregulation of neuronal-activity-dependent signaling plays a significant part in the etiology of neuropsychiatric and neurodevelopmental disorders. Copyright © 2017 the authors 0270-6474/17/3710516-12$15.00/0.

  8. Molecular properties of Zic4 and Zic5 proteins: functional diversity within Zic family

    International Nuclear Information System (INIS)

    Ishiguro, Akira; Inoue, Takashi; Mikoshiba, Katuhiko; Aruga, Jun

    2004-01-01

    The Zic-family proteins control various developmental processes. Previous studies have shown that Zic1, Zic2, and Zic3 can act as transcriptional regulators, and that their functions are repressed by I-mfa, which has been identified as a repressor for basic helix-loop-helix-type transcriptional factors. Here, we investigated the molecular properties of the Zic4 and Zic5 proteins. Zic4/Zic5 showed DNA-binding activity to the Gli-binding sequence, similar to Zic1/Zic2/Zic3 proteins. However, Zic4/Zic5 did not exhibit any significant transcriptional activation ability nor they bind to I-mfa differently from Zic1/Zic2/Zic3. The nuclear localization of Zic4/Zic5 was not affected by the presence of the I-mfa protein, whereas the Zic1/Zic2/Zic3 proteins were translocated to the cytoplasmic compartment in the presence of I-mfa. The difference may be attributable to the dissimilarity of the N-terminal region between the Zic1/Zic2/Zic3 and Zic4/Zic5 proteins, since the binding of the Zic1/Zic2/Zic3 proteins to I-mfa occurs through their N-terminal regions

  9. Ubiquitination-Related MdBT Scaffold Proteins Target a bHLH Transcription Factor for Iron Homeostasis1[OPEN

    Science.gov (United States)

    Zhao, Qiang; Wang, Qing-Jie; Wang, Xiao-Fei; You, Chun-Xiang

    2016-01-01

    Iron (Fe) homeostasis is crucial for plant growth and development. A network of basic helix-loop-helix (bHLH) transcription factors positively regulates Fe uptake during iron deficiency. However, their up-regulation or overexpression leads to Fe overload and reactive oxygen species generation, thereby damaging the plants. Here, we found that two BTB/TAZ proteins, MdBT1 and MdBT2, interact with the MbHLH104 protein in apple. In addition, the function of MdBT2 was characterized as a regulator of MdbHLH104 degradation via ubiquitination and the 26S proteasome pathway, thereby controlling the activity of plasma membrane H+-ATPases and the acquisition of iron. Furthermore, MdBT2 interacted with MdCUL3 proteins, which were required for the MdBT2-mediated ubiquitination modification of MdbHLH104 and its degradation. In sum, our findings demonstrate that MdBT proteins interact with MdCUL3 to bridge the formation of the MdBTsMdCUL3 complex, which negatively modulates the degradation of the MdbHLH104 protein in response to changes in Fe status to maintain iron homeostasis in plants. PMID:27660166

  10. Scaffold protein enigma homolog 1 overcomes the repression of myogenesis activation by inhibitor of DNA binding 2

    International Nuclear Information System (INIS)

    Nakatani, Miyuki; Ito, Jumpei; Koyama, Riko; Iijima, Masumi; Yoshimoto, Nobuo; Niimi, Tomoaki; Kuroda, Shun'ichi; Maturana, Andrés D.

    2016-01-01

    Enigma Homolog 1 (ENH1) is a scaffold protein for signaling proteins and transcription factors. Previously, we reported that ENH1 overexpression promotes the differentiation of C2C12 myoblasts. However, the molecular mechanism underlying the role of ENH1 in the C2C12 cells differentiation remains elusive. ENH1 was shown to inhibit the proliferation of neuroblastoma cells by sequestering Inhibitor of DNA binding protein 2 (Id2) in the cytosol. Id2 is a repressor of basic Helix-Loop-Helix transcription factors activity and prevents myogenesis. Here, we found that ENH1 overcome the Id2 repression of C2C12 cells myogenic differentiation and that ENH1 overexpression promotes mice satellite cells activation, the first step toward myogenic differentiation. In addition, we show that ENH1 interacted with Id2 in C2C12 cells and mice satellite cells. Collectively, our results suggest that ENH1 plays an important role in the activation of myogenesis through the repression of Id2 activity. -- Highlights: •Enigma Homolog 1 (ENH1) is a scaffold protein. •ENH1 binds to inhibitor of DNA binding 2 (Id2) in myoblasts. •ENH1 overexpression overcomes the Id2's repression of myogenesis. •The Id2-ENH1 complex play an important role in the activation of myogenesis.

  11. Scaffold protein enigma homolog 1 overcomes the repression of myogenesis activation by inhibitor of DNA binding 2

    Energy Technology Data Exchange (ETDEWEB)

    Nakatani, Miyuki [Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Nagoya, 464-8106 (Japan); Ito, Jumpei [Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Nagoya, 464-8106 (Japan); Japan Society for the Promotion of Science, Tokyo, 102-0083 (Japan); Koyama, Riko [Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Nagoya, 464-8106 (Japan); Iijima, Masumi; Yoshimoto, Nobuo [The Institute of Scientific and Industrial Research, Osaka University, 8-1 Mihogaoka, Ibaraki, Osaka, 567-0047 (Japan); Niimi, Tomoaki [Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Nagoya, 464-8106 (Japan); Kuroda, Shun' ichi [Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Nagoya, 464-8106 (Japan); The Institute of Scientific and Industrial Research, Osaka University, 8-1 Mihogaoka, Ibaraki, Osaka, 567-0047 (Japan); Maturana, Andrés D., E-mail: maturana@agr.nagoya-u.ac.jp [Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Nagoya, 464-8106 (Japan)

    2016-05-27

    Enigma Homolog 1 (ENH1) is a scaffold protein for signaling proteins and transcription factors. Previously, we reported that ENH1 overexpression promotes the differentiation of C2C12 myoblasts. However, the molecular mechanism underlying the role of ENH1 in the C2C12 cells differentiation remains elusive. ENH1 was shown to inhibit the proliferation of neuroblastoma cells by sequestering Inhibitor of DNA binding protein 2 (Id2) in the cytosol. Id2 is a repressor of basic Helix-Loop-Helix transcription factors activity and prevents myogenesis. Here, we found that ENH1 overcome the Id2 repression of C2C12 cells myogenic differentiation and that ENH1 overexpression promotes mice satellite cells activation, the first step toward myogenic differentiation. In addition, we show that ENH1 interacted with Id2 in C2C12 cells and mice satellite cells. Collectively, our results suggest that ENH1 plays an important role in the activation of myogenesis through the repression of Id2 activity. -- Highlights: •Enigma Homolog 1 (ENH1) is a scaffold protein. •ENH1 binds to inhibitor of DNA binding 2 (Id2) in myoblasts. •ENH1 overexpression overcomes the Id2's repression of myogenesis. •The Id2-ENH1 complex play an important role in the activation of myogenesis.

  12. Light-mediated Reversible Modulation of the Mitogen-activated Protein Kinase Pathway during Cell Differentiation and Xenopus Embryonic Development.

    Science.gov (United States)

    Krishnamurthy, Vishnu V; Turgeon, Aurora J; Khamo, John S; Mondal, Payel; Sharum, Savanna R; Mei, Wenyan; Yang, Jing; Zhang, Kai

    2017-06-15

    Kinase activity is crucial for a plethora of cellular functions, including cell proliferation, differentiation, migration, and apoptosis. During early embryonic development, kinase activity is highly dynamic and widespread across the embryo. Pharmacological and genetic approaches are commonly used to probe kinase activities. Unfortunately, it is challenging to achieve superior spatial and temporal resolution using these strategies. Furthermore, it is not feasible to control the kinase activity in a reversible fashion in live cells and multicellular organisms. Such a limitation remains a bottleneck for achieving a quantitative understanding of kinase activity during development and differentiation. This work presents an optogenetic strategy that takes advantage of a bicistronic system containing photoactivatable proteins Arabidopsis thaliana cryptochrome 2 (CRY2) and the N-terminal domain of cryptochrome-interacting basic-helix-loop-helix (CIBN). Reversible activation of the mitogen-activated protein kinase (MAPK) signaling pathway is achieved through light-mediated protein translocation in live cells. This approach can be applied to mammalian cell cultures and live vertebrate embryos. This bicistronic system can be generalized to control the activity of other kinases with similar activation mechanisms and can be applied to other model systems.

  13. Scaffold protein enigma homolog 1 overcomes the repression of myogenesis activation by inhibitor of DNA binding 2.

    Science.gov (United States)

    Nakatani, Miyuki; Ito, Jumpei; Koyama, Riko; Iijima, Masumi; Yoshimoto, Nobuo; Niimi, Tomoaki; Kuroda, Shun'ichi; Maturana, Andrés D

    2016-05-27

    Enigma Homolog 1 (ENH1) is a scaffold protein for signaling proteins and transcription factors. Previously, we reported that ENH1 overexpression promotes the differentiation of C2C12 myoblasts. However, the molecular mechanism underlying the role of ENH1 in the C2C12 cells differentiation remains elusive. ENH1 was shown to inhibit the proliferation of neuroblastoma cells by sequestering Inhibitor of DNA binding protein 2 (Id2) in the cytosol. Id2 is a repressor of basic Helix-Loop-Helix transcription factors activity and prevents myogenesis. Here, we found that ENH1 overcome the Id2 repression of C2C12 cells myogenic differentiation and that ENH1 overexpression promotes mice satellite cells activation, the first step toward myogenic differentiation. In addition, we show that ENH1 interacted with Id2 in C2C12 cells and mice satellite cells. Collectively, our results suggest that ENH1 plays an important role in the activation of myogenesis through the repression of Id2 activity. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Inhibitory PAS domain protein is a negative regulator of hypoxia-inducible gene expression

    Science.gov (United States)

    Makino, Yuichi; Cao, Renhai; Svensson, Kristian; Bertilsson, Göran; Asman, Mikael; Tanaka, Hirotoshi; Cao, Yihai; Berkenstam, Anders; Poellinger, Lorenz

    2001-11-01

    Alteration of gene expression is a crucial component of adaptive responses to hypoxia. These responses are mediated by hypoxia-inducible transcription factors (HIFs). Here we describe an inhibitory PAS (Per/Arnt/Sim) domain protein, IPAS, which is a basic helix-loop-helix (bHLH)/PAS protein structurally related to HIFs. IPAS contains no endogenous transactivation function but demonstrates dominant negative regulation of HIF-mediated control of gene expression. Ectopic expression of IPAS in hepatoma cells selectively impairs induction of genes involved in adaptation to a hypoxic environment, notably the vascular endothelial growth factor (VEGF) gene, and results in retarded tumour growth and tumour vascular density in vivo. In mice, IPAS was predominantly expressed in Purkinje cells of the cerebellum and in corneal epithelium of the eye. Expression of IPAS in the cornea correlates with low levels of expression of the VEGF gene under hypoxic conditions. Application of an IPAS antisense oligonucleotide to the mouse cornea induced angiogenesis under normal oxygen conditions, and demonstrated hypoxia-dependent induction of VEGF gene expression in hypoxic corneal cells. These results indicate a previously unknown mechanism for negative regulation of angiogenesis and maintenance of an avascular phenotype.

  15. MAP Kinase Cascades Regulate the Cold Response by Modulating ICE1 Protein Stability.

    Science.gov (United States)

    Zhao, Chunzhao; Wang, Pengcheng; Si, Tong; Hsu, Chuan-Chih; Wang, Lu; Zayed, Omar; Yu, Zheping; Zhu, Yingfang; Dong, Juan; Tao, W Andy; Zhu, Jian-Kang

    2017-12-04

    Mitogen-activated protein kinase cascades are important signaling modules that convert environmental stimuli into cellular responses. We show that MPK3, MPK4, and MPK6 are rapidly activated after cold treatment. The mpk3 and mpk6 mutants display increased expression of CBF genes and enhanced freezing tolerance, whereas constitutive activation of the MKK4/5-MPK3/6 cascade in plants causes reduced expression of CBF genes and hypersensitivity to freezing, suggesting that the MKK4/5-MPK3/6 cascade negatively regulates the cold response. MPK3 and MPK6 can phosphorylate ICE1, a basic-helix-loop-helix transcription factor that regulates the expression of CBF genes, and the phosphorylation promotes the degradation of ICE1. Interestingly, the MEKK1-MKK2-MPK4 pathway constitutively suppresses MPK3 and MPK6 activities and has a positive role in the cold response. Furthermore, the MAPKKK YDA and two calcium/calmodulin-regulated receptor-like kinases, CRLK1 and CRLK2, negatively modulate the cold activation of MPK3/6. Our results uncover important roles of MAPK cascades in the regulation of plant cold response. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. An effective approach for identification of in vivo protein-DNA binding sites from paired-end ChIP-Seq data

    Directory of Open Access Journals (Sweden)

    Wilson Zoe A

    2010-02-01

    Full Text Available Abstract Background ChIP-Seq, which combines chromatin immunoprecipitation (ChIP with high-throughput massively parallel sequencing, is increasingly being used for identification of protein-DNA interactions in vivo in the genome. However, to maximize the effectiveness of data analysis of such sequences requires the development of new algorithms that are able to accurately predict DNA-protein binding sites. Results Here, we present SIPeS (Site Identification from Paired-end Sequencing, a novel algorithm for precise identification of binding sites from short reads generated by paired-end solexa ChIP-Seq technology. In this paper we used ChIP-Seq data from the Arabidopsis basic helix-loop-helix transcription factor ABORTED MICROSPORES (AMS, which is expressed within the anther during pollen development, the results show that SIPeS has better resolution for binding site identification compared to two existing ChIP-Seq peak detection algorithms, Cisgenome and MACS. Conclusions When compared to Cisgenome and MACS, SIPeS shows better resolution for binding site discovery. Moreover, SIPeS is designed to calculate the mappable genome length accurately with the fragment length based on the paired-end reads. Dynamic baselines are also employed to effectively discriminate closely adjacent binding sites, for effective binding sites discovery, which is of particular value when working with high-density genomes.

  17. The clockwork orange Drosophila protein functions as both an activator and a repressor of clock gene expression.

    Science.gov (United States)

    Richier, Benjamin; Michard-Vanhée, Christine; Lamouroux, Annie; Papin, Christian; Rouyer, François

    2008-04-01

    The Drosophila clock relies on transcriptional feedback loops that generate daily oscillations of the clock gene expression at mRNA and protein levels. In the evening, the CLOCK (CLK) and CYCLE (CYC) basic helix-loop-helix (bHLH) PAS-domain transcription factors activate the expression of the period (per) and timeless (tim) genes. Posttranslational modifications delay the accumulation of PER and TIM, which inhibit CLK/CYC activity in the late night. We show here that a null mutant of the clockwork orange (cwo) gene encoding a bHLH orange-domain putative transcription factor displays long-period activity rhythms. cwo loss of function increases cwo mRNA levels but reduces mRNA peak levels of the 4 described CLK/CYC targets, inducing an almost complete loss of their cycling. In addition, the absence of CWO induces alterations of PER and CLK phosphorylation cycles. Our results indicate that, in vivo, CWO modulates clock gene expression through both repressor and activator transcriptional functions.

  18. AcEST: DK950560 [AcEST

    Lifescience Database Archive (English)

    Full Text Available A0|UVRC_SYNWW UvrABC system protein C OS=Syntrophomonas w... 36 0.28 sp|Q9NX45|SOLH2_HUMAN Spermatogenesis- and oogenesis...HUMAN Spermatogenesis- and oogenesis-specific basic helix-loop-helix-containing protein 2 OS=Homo sapiens GN

  19. NEUROD2 and NEUROD3 genes map to human chromosomes 17q12 and 5q23-q31 and mouse chromosomes 11 and 13, respectively

    Energy Technology Data Exchange (ETDEWEB)

    Tamimi, R.M.; Montgomery-Dyer, K.; Tapscott, S.J. [Fred Hutchinson Cancer Research Center, Seattle, WA (United States)] [and others

    1997-03-01

    NEUROD2 and NEUROD3 are transcription factors involved in neurogenesis that are related to the basic helix-loop-helix protein NEUROD. NEUROD2 maps to human chromosome 17q12 and mouse chromosome 11. NEUROD3 maps to human chromosome 5q23-q31 and mouse chromosome 13. 16 refs., 2 figs.

  20. MYC2, MYC3, and MYC4 function redundantly in seed storage protein accumulation in Arabidopsis.

    Science.gov (United States)

    Gao, Chenhao; Qi, Shuanghui; Liu, Kaige; Li, Dong; Jin, Changyu; Li, Zhuowei; Huang, Gengqing; Hai, Jiangbo; Zhang, Meng; Chen, Mingxun

    2016-11-01

    Basic helix-loop-helix transcription factors (TFs), namely MYC2, MYC3, and MYC4, interact with Jasmonate Zim-domain proteins and are their direct targets. These TFs have been shown to function synergistically to control Arabidopsis growth and development. Our results showed similar MYC2, MYC3, and MYC4 expression patterns during Arabidopsis seed development, which remained relatively high during seed mid-maturation. MYC2, MYC3, and MYC4 acted redundantly in seed size, weight control, and in regulating seed storage protein accumulation. Triple mutants produced the largest seeds and single and double mutants' seeds were much larger than those of wild type. The weight of triple mutants' seeds was significantly higher than that of wild-type seeds, which was accompanied by an increase in seed storage protein contents. Triple mutants' seeds presented a marked decrease in 2S amounts relative to those in wild-type seeds. Liquid chromatography tandem mass spectra sequencing results indicated that both the relative abundance and the peptide number of CRA1 and CRU3 were greatly increased in triple mutants compared to wild type. The expression of 2S1-2S5 decreased and that of CRA1 and CRU3 increased in triple mutants relative to those in wild types during seed development, which might have contributed to the low 2S and high 12S contents in triple mutants. Our results contribute to understanding the function of MYC2, MYC3, and MYC4 on seed development, and provide promising targets for genetic manipulations of protein-producing crops to improve the quantity and quality of seed storage proteins. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  1. Efficient generation of dopamine neuron-like cells from skin-derived precursors with a synthetic peptide derived from von Hippel-Lindau protein.

    Science.gov (United States)

    Kubo, Atsuhiko; Yoshida, Tetsuhiko; Kobayashi, Nahoko; Yokoyama, Takaakira; Mimura, Toshiro; Nishiguchi, Takao; Higashida, Tetsuhiro; Yamamoto, Isao; Kanno, Hiroshi

    2009-12-01

    Skin-derived precursors (SKPs) from mammalian dermis represent neural crest-related stem cells capable of differentiating into both neural and mesodermal progency. SKPs are of clinical interest because they serve as accessible autologous donor cells for neuronal repair for neuronal intractable diseases. However, little is known about the efficient generation of neurons from SKPs, and phenotypes of neurons generated from SKPs have been restricted. In addition, the neuronal repair using their generated neurons as donor cells has not been achieved. The von Hippel-Lindau protein (pVHL) is one of the proteins that play an important role during neuronal differentiation, and recently neuronal differentiation of neural progenitor cells by intracellular delivery of a synthetic VHL peptide derived from elongin BC-binding site has been demonstrated. In the present study, a synthetic VHL peptide derived from elongin BC-binding site was conjugated to the protein transduction domain (PTD) of HIV-TAT protein (TATVHL peptide) to facilitate entry into cells, and we demonstrate the efficient generation of cells with dopaminergic phenotype from SKPs with the intracellular delivery of TATVHL peptide, and characterized the generated cells. The TATVHL peptide-treated SKPs expressed neuronal marker proteins, particularly dopamine neuron markers, and also up-regulated mRNA levels of proneural basic helix-loop-helix factors. After the TATVHL peptide treatment, transplanted SKPs into Parkinson's disease (PD) model rats sufficiently differentiated into dopamine neuron-like cells in PD model rats, and partially but significantly corrected behavior of PD model rats. The generated dopamine neuron-like cells are expected to serve as donor cells for neuronal repair for PD.

  2. E(spl): genetic, developmental, and evolutionary aspects of a group of invertebrate Hes proteins with close ties to Notch signaling.

    Science.gov (United States)

    Delidakis, Christos; Monastirioti, Maria; Magadi, Srivathsa S

    2014-01-01

    Enhancer-of-split (E(spl)) was genetically characterized in Drosophila as a dominant mutation that interacts with an allele of Notch, the receptor in a multipurpose signaling pathway throughout development. Although dominant mutations are often not informative of the normal gene function, E(spl) turned out to encode a family of seven paralogous basic helix-loop-helix proteins of utmost importance in the implementation of the Notch signal in the receiving cell. They are transcriptionally induced by Notch in almost every instance where the signal is deployed, and they participate in numerous feedback circuits, where they interface with a panoply of additional more tissue-specific Notch targets to ensure the proper signaling outcome. Besides the bHLH domain, E(spl) contain a characteristic Orange domain and are classified in the Hes (hairy and enhancer-of-split) branch of the bHLH-Orange proteins. They act as DNA-binding repressors in close collaboration with the corepressor Groucho. In this review, we will focus on the regulation of E(spl) expression and on the function of E(spl) proteins. In the latter section, we will present some of the best-studied developmental events where E(spl) function has been analysed as well as the molecular mechanism of E(spl) activity that has transpired. Finally, we will review the evolution of this protein family, which, albeit of relatively recent origin, present only in insects and crustaceans, has undergone extensive diversification, including gene loss and duplication. Importantly, many of the characteristics of E(spl) proteins are more deeply rooted in the very ancient larger bHLH-O family, which seems to have forged a connection with the Notch pathway from the very beginning of multicellular animal life. © 2014 Elsevier Inc. All rights reserved.

  3. Zinc finger transcription factors displaced SREBP proteins as the major Sterol regulators during Saccharomycotina evolution.

    Directory of Open Access Journals (Sweden)

    Sarah L Maguire

    2014-01-01

    Full Text Available In most eukaryotes, including the majority of fungi, expression of sterol biosynthesis genes is regulated by Sterol-Regulatory Element Binding Proteins (SREBPs, which are basic helix-loop-helix transcription activators. However, in yeasts such as Saccharomyces cerevisiae and Candida albicans sterol synthesis is instead regulated by Upc2, an unrelated transcription factor with a Gal4-type zinc finger. The SREBPs in S. cerevisiae (Hms1 and C. albicans (Cph2 have lost a domain, are not major regulators of sterol synthesis, and instead regulate filamentous growth. We report here that rewiring of the sterol regulon, with Upc2 taking over from SREBP, likely occurred in the common ancestor of all Saccharomycotina. Yarrowia lipolytica, a deep-branching species, is the only genome known to contain intact and full-length orthologs of both SREBP (Sre1 and Upc2. Deleting YlUPC2, but not YlSRE1, confers susceptibility to azole drugs. Sterol levels are significantly reduced in the YlUPC2 deletion. RNA-seq analysis shows that hypoxic regulation of sterol synthesis genes in Y. lipolytica is predominantly mediated by Upc2. However, YlSre1 still retains a role in hypoxic regulation; growth of Y. lipolytica in hypoxic conditions is reduced in a Ylupc2 deletion and is abolished in a Ylsre1/Ylupc2 double deletion, and YlSre1 regulates sterol gene expression during hypoxia adaptation. We show that YlSRE1, and to a lesser extent YlUPC2, are required for switching from yeast to filamentous growth in hypoxia. Sre1 appears to have an ancestral role in the regulation of filamentation, which became decoupled from its role in sterol gene regulation by the arrival of Upc2 in the Saccharomycotina.

  4. The bHLH proteins BEE and BIM positively modulate the shade avoidance syndrome in Arabidopsis seedlings.

    Science.gov (United States)

    Cifuentes-Esquivel, Nicolás; Bou-Torrent, Jordi; Galstyan, Anahit; Gallemí, Marçal; Sessa, Giovanna; Salla Martret, Mercè; Roig-Villanova, Irma; Ruberti, Ida; Martínez-García, Jaime F

    2013-09-01

    The shade avoidance syndrome (SAS) refers to a set of plant responses initiated after perception by the phytochromes of light with a reduced red to far-red ratio, indicative of vegetation proximity or shade. These responses, including elongation growth, anticipate eventual shading from potential competitor vegetation by overgrowing neighboring plants or flowering to ensure production of viable seeds for the next generation. In Arabidopsis thaliana seedlings, the SAS includes dramatic changes in gene expression, such as induction of PHYTOCHROME RAPIDLY REGULATED 1 (PAR1), encoding an atypical basic helix-loop-helix (bHLH) protein that acts as a transcriptional co-factor to repress hypocotyl elongation. Indeed, PAR1 has been proposed to act fundamentally as a dominant negative antagonist of conventional bHLH transcription factors by forming heterodimers with them to prevent their binding to DNA or other transcription factors. Here we report the identification of PAR1-interacting factors, including the brassinosteroid signaling components BR-ENHANCED EXPRESSION (BEE) and BES1-INTERACTING MYC-LIKE (BIM), and characterize their role as networked positive regulators of SAS hypocotyl responses. We provide genetic evidence that these bHLH transcriptional regulators not only control plant growth and development under shade and non-shade conditions, but are also redundant in the control of plant viability. Our results suggest that SAS responses are initiated as a consequence of a new balance of transcriptional regulators within the pre-existing bHLH network triggered by plant proximity, eventually causing hypocotyls to elongate. © 2013 The Authors The Plant Journal © 2013 John Wiley & Sons Ltd.

  5. Identifying Novel Helix-Loop-Helix Genes in "Caenorhabditis elegans" through a Classroom Demonstration of Functional Genomics

    Science.gov (United States)

    Griffin, Vernetta; McMiller, Tracee; Jones, Erika; Johnson, Casonya M.

    2003-01-01

    A 14-week, undergraduate-level Genetics and Population Biology course at Morgan State University was modified to include a demonstration of functional genomics in the research laboratory. Students performed a rudimentary sequence analysis of the "Caenorhabditis elegans" genome and further characterized three sequences that were predicted to encode…

  6. The MYB182 protein down-regulates proanthocyanidin and anthocyanin biosynthesis in poplar by repressing both structural and regulatory flavonoid genes.

    Science.gov (United States)

    Yoshida, Kazuko; Ma, Dawei; Constabel, C Peter

    2015-03-01

    Trees in the genus Populus (poplar) contain phenolic secondary metabolites including the proanthocyanidins (PAs), which help to adapt these widespread trees to diverse environments. The transcriptional activation of PA biosynthesis in response to herbivory and ultraviolet light stress has been documented in poplar leaves, and a regulator of this process, the R2R3-MYB transcription factor MYB134, has been identified. MYB134-overexpressing transgenic plants show a strong high-PA phenotype. Analysis of these transgenic plants suggested the involvement of additional MYB transcription factors, including repressor-like MYB factors. Here, MYB182, a subgroup 4 MYB factor, was found to act as a negative regulator of the flavonoid pathway. Overexpression of MYB182 in hairy root culture and whole poplar plants led to reduced PA and anthocyanin levels as well as a reduction in the expression of key flavonoid genes. Similarly, a reduced accumulation of transcripts of a MYB PA activator and a basic helix-loop-helix cofactor was observed in MYB182-overexpressing hairy roots. Transient promoter activation assays in poplar cell culture demonstrated that MYB182 can disrupt transcriptional activation by MYB134 and that the basic helix-loop-helix-binding motif of MYB182 was essential for repression. Microarray analysis of transgenic plants demonstrated that down-regulated targets of MYB182 also include shikimate pathway genes. This work shows that MYB182 plays an important role in the fine-tuning of MYB134-mediated flavonoid metabolism. © 2015 American Society of Plant Biologists. All Rights Reserved.

  7. Molecular and Structural Characterization of the Tegumental 20.6-kDa Protein in Clonorchis sinensis as a Potential Druggable Target

    Directory of Open Access Journals (Sweden)

    Yu-Jung Kim

    2017-03-01

    Full Text Available The tegument, representing the membrane-bound outer surface of platyhelminth parasites, plays an important role for the regulation of the host immune response and parasite survival. A comprehensive understanding of tegumental proteins can provide drug candidates for use against helminth-associated diseases, such as clonorchiasis caused by the liver fluke Clonorchis sinensis. However, little is known regarding the physicochemical properties of C. sinensis teguments. In this study, a novel 20.6-kDa tegumental protein of the C. sinensis adult worm (CsTegu20.6 was identified and characterized by molecular and in silico methods. The complete coding sequence of 525 bp was derived from cDNA clones and encodes a protein of 175 amino acids. Homology search using BLASTX showed CsTegu20.6 identity ranging from 29% to 39% with previously-known tegumental proteins in C. sinensis. Domain analysis indicated the presence of a calcium-binding EF-hand domain containing a basic helix-loop-helix structure and a dynein light chain domain exhibiting a ferredoxin fold. We used a modified method to obtain the accurate tertiary structure of the CsTegu20.6 protein because of the unavailability of appropriate templates. The CsTegu20.6 protein sequence was split into two domains based on the disordered region, and then, the structure of each domain was modeled using I-TASSER. A final full-length structure was obtained by combining two structures and refining the whole structure. A refined CsTegu20.6 structure was used to identify a potential CsTegu20.6 inhibitor based on protein structure-compound interaction analysis. The recombinant proteins were expressed in Escherichia coli and purified by nickel-nitrilotriacetic acid affinity chromatography. In C. sinensis, CsTegu20.6 mRNAs were abundant in adult and metacercariae, but not in the egg. Immunohistochemistry revealed that CsTegu20.6 localized to the surface of the tegument in the adult fluke. Collectively, our results

  8. Molecular and Structural Characterization of the Tegumental 20.6-kDa Protein in Clonorchis sinensis as a Potential Druggable Target.

    Science.gov (United States)

    Kim, Yu-Jung; Yoo, Won Gi; Lee, Myoung-Ro; Kang, Jung-Mi; Na, Byoung-Kuk; Cho, Shin-Hyeong; Park, Mi-Yeoun; Ju, Jung-Won

    2017-03-04

    The tegument, representing the membrane-bound outer surface of platyhelminth parasites, plays an important role for the regulation of the host immune response and parasite survival. A comprehensive understanding of tegumental proteins can provide drug candidates for use against helminth-associated diseases, such as clonorchiasis caused by the liver fluke Clonorchis sinensis . However, little is known regarding the physicochemical properties of C. sinensis teguments. In this study, a novel 20.6-kDa tegumental protein of the C. sinensis adult worm (CsTegu20.6) was identified and characterized by molecular and in silico methods. The complete coding sequence of 525 bp was derived from cDNA clones and encodes a protein of 175 amino acids. Homology search using BLASTX showed CsTegu20.6 identity ranging from 29% to 39% with previously-known tegumental proteins in C. sinensis . Domain analysis indicated the presence of a calcium-binding EF-hand domain containing a basic helix-loop-helix structure and a dynein light chain domain exhibiting a ferredoxin fold. We used a modified method to obtain the accurate tertiary structure of the CsTegu20.6 protein because of the unavailability of appropriate templates. The CsTegu20.6 protein sequence was split into two domains based on the disordered region, and then, the structure of each domain was modeled using I-TASSER. A final full-length structure was obtained by combining two structures and refining the whole structure. A refined CsTegu20.6 structure was used to identify a potential CsTegu20.6 inhibitor based on protein structure-compound interaction analysis. The recombinant proteins were expressed in Escherichia coli and purified by nickel-nitrilotriacetic acid affinity chromatography. In C. sinensis , CsTegu20.6 mRNAs were abundant in adult and metacercariae, but not in the egg. Immunohistochemistry revealed that CsTegu20.6 localized to the surface of the tegument in the adult fluke. Collectively, our results contribute to a

  9. Impairment of different protein domains causes variable clinical presentation within Pitt-Hopkins syndrome and suggests intragenic molecular syndromology of TCF4.

    Science.gov (United States)

    Bedeschi, Maria Francesca; Marangi, Giuseppe; Calvello, Maria Rosaria; Ricciardi, Stefania; Leone, Francesca Pia Chiara; Baccarin, Marco; Guerneri, Silvana; Orteschi, Daniela; Murdolo, Marina; Lattante, Serena; Frangella, Silvia; Keena, Beth; Harr, Margaret H; Zackai, Elaine; Zollino, Marcella

    2017-11-01

    Pitt-Hopkins syndrome is a neurodevelopmental disorder characterized by severe intellectual disability and a distinctive facial gestalt. It is caused by haploinsufficiency of the TCF4 gene. The TCF4 protein has different functional domains, with the NLS (nuclear localization signal) domain coded by exons 7-8 and the bHLH (basic Helix-Loop-Helix) domain coded by exon 18. Several alternatively spliced TCF4 variants have been described, allowing for translation of variable protein isoforms. Typical PTHS patients have impairment of at least the bHLH domain. To which extent impairment of the remaining domains contributes to the final phenotype is not clear. There is recent evidence that certain loss-of-function variants disrupting TCF4 are associated with mild ID, but not with typical PTHS. We describe a frameshift-causing partial gene deletion encompassing exons 4-6 of TCF4 in an adult patient with mild ID and nonspecific facial dysmorphisms but without the typical features of PTHS, and a c.520C > T nonsense variant within exon 8 in a child presenting with a severe phenotype largely mimicking PTHS, but lacking the typical facial dysmorphism. Investigation on mRNA, along with literature review, led us to suggest a preliminary phenotypic map of loss-of-function variants affecting TCF4. An intragenic phenotypic map of loss-of-function variants in TCF4 is suggested here for the first time: variants within exons 1-4 and exons 4-6 give rise to a recurrent phenotype with mild ID not in the spectrum of Pitt-Hopkins syndrome (biallelic preservation of both the NLS and bHLH domains); variants within exons 7-8 cause a severe phenotype resembling PTHS but in absence of the typical facial dysmorphism (impairment limited to the NLS domain); variants within exons 9-19 cause typical Pitt-Hopkins syndrome (impairment of at least the bHLH domain). Understanding the TCF4 molecular syndromology can allow for proper nosology in the current era of whole genomic investigations. Copyright

  10. Nonenzymatic glycosylation of bovine myelin basic protein

    International Nuclear Information System (INIS)

    Hitz, J.B.

    1987-01-01

    In the CNS myelin sheath the nonenzymatic glycosylation reaction (at the early stage of the Amadori product) occurs only with the myelin basic protein and not with the other myelin proteins. This was observed in isolated bovine myelin by in vitro incubation with [ 14 C]-galactose and [ 14 C]-glucose. The respective in-vitro incorporation rates for purified bovine myelin basic protein with D-galactose, D-glucose and D-mannose were 7.2, 2.4 and 2.4 mmoles/mole myelin basic protein per day at 37 0 C. A more rapid, HPLC method was devised and characterized to specifically analyze for the Amadori product. The HPLC method was correlated to the [ 14 C]-sugar incorporation method for myelin basic protein under a set of standard reaction conditions using [ 14 C]-glucose and [ 14 C]-mannose with HPLC values at 1/6 and 1/5 of the [ 14 C]-sugar incorporation method. A novel myelin basic protein purification step has been developed that yields a relativity proteolytic free preparation that is easy to work with, being totally soluble at a neutral pH. Nine new spots appear for a trypsinized glycosylated MBP in the paper peptide map of which eight correspond to positions of the [ 3 H]-labeled Amadori product in affinity isolated peptides. These studies provide a general characterization of and a structural basis for investigations on nonenzymatically glycosylated MBP as well as identifying MBP as the only nonenzymatically glycosylated protein in the CNS myelin sheath which may accumulate during aging, diabetes, and demyelinating diseases in general

  11. Functional and structural properties of a novel protein and virulence factor (Protein sHIP) in Streptococcus pyogenes.

    Science.gov (United States)

    Wisniewska, Magdalena; Happonen, Lotta; Kahn, Fredrik; Varjosalo, Markku; Malmström, Lars; Rosenberger, George; Karlsson, Christofer; Cazzamali, Giuseppe; Pozdnyakova, Irina; Frick, Inga-Maria; Björck, Lars; Streicher, Werner; Malmström, Johan; Wikström, Mats

    2014-06-27

    Streptococcus pyogenes is a significant bacterial pathogen in the human population. The importance of virulence factors for the survival and colonization of S. pyogenes is well established, and many of these factors are exposed to the extracellular environment, enabling bacterial interactions with the host. In the present study, we quantitatively analyzed and compared S. pyogenes proteins in the growth medium of a strain that is virulent to mice with a non-virulent strain. Particularly, one of these proteins was present at significantly higher levels in stationary growth medium from the virulent strain. We determined the three-dimensional structure of the protein that showed a unique tetrameric organization composed of four helix-loop-helix motifs. Affinity pull-down mass spectrometry analysis in human plasma demonstrated that the protein interacts with histidine-rich glycoprotein (HRG), and the name sHIP (streptococcal histidine-rich glycoprotein-interacting protein) is therefore proposed. HRG has antibacterial activity, and when challenged by HRG, sHIP was found to rescue S. pyogenes bacteria. This and the finding that patients with invasive S. pyogenes infection respond with antibody production against sHIP suggest a role for the protein in S. pyogenes pathogenesis. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

  12. Functional and Structural Properties of a Novel Protein and Virulence Factor (Protein sHIP) in Streptococcus pyogenes *

    Science.gov (United States)

    Wisniewska, Magdalena; Happonen, Lotta; Kahn, Fredrik; Varjosalo, Markku; Malmström, Lars; Rosenberger, George; Karlsson, Christofer; Cazzamali, Giuseppe; Pozdnyakova, Irina; Frick, Inga-Maria; Björck, Lars; Streicher, Werner; Malmström, Johan; Wikström, Mats

    2014-01-01

    Streptococcus pyogenes is a significant bacterial pathogen in the human population. The importance of virulence factors for the survival and colonization of S. pyogenes is well established, and many of these factors are exposed to the extracellular environment, enabling bacterial interactions with the host. In the present study, we quantitatively analyzed and compared S. pyogenes proteins in the growth medium of a strain that is virulent to mice with a non-virulent strain. Particularly, one of these proteins was present at significantly higher levels in stationary growth medium from the virulent strain. We determined the three-dimensional structure of the protein that showed a unique tetrameric organization composed of four helix-loop-helix motifs. Affinity pull-down mass spectrometry analysis in human plasma demonstrated that the protein interacts with histidine-rich glycoprotein (HRG), and the name sHIP (streptococcal histidine-rich glycoprotein-interacting protein) is therefore proposed. HRG has antibacterial activity, and when challenged by HRG, sHIP was found to rescue S. pyogenes bacteria. This and the finding that patients with invasive S. pyogenes infection respond with antibody production against sHIP suggest a role for the protein in S. pyogenes pathogenesis. PMID:24825900

  13. Autonomous regulation of the insect gut by circadian genes acting downstream of juvenile hormone signaling

    Czech Academy of Sciences Publication Activity Database

    Bajgar, Adam; Jindra, Marek; Doležel, David

    2013-01-01

    Roč. 110, č. 11 (2013), s. 4416-4421 ISSN 0027-8424 R&D Projects: GA AV ČR IAA500960802; GA ČR GP204/08/P579; GA ČR GAP502/10/1612 Grant - others:Marie Curie Fellowship Award(CZ) 276569 Institutional research plan: CEZ:AV0Z50070508 Keywords : reproductive diapuase * photoperiodism * basic helix-loop-helix protein Subject RIV: ED - Physiology Impact factor: 9.809, year: 2013 http://www.pnas.org/content/110/11/4416.full.pdf+html

  14. Dose-dependent regulation of target gene expression and cell proliferation by c-Myc levels

    OpenAIRE

    Schuhmacher, Marino; Eick, Dirk

    2013-01-01

    The proto-oncogene c-myc encodes a basic helix-loop-helix leucine zipper transcription factor (c-Myc). c-Myc plays a crucial role in cell growth and proliferation. Here, we examined how expression of c-Myc target genes and cell proliferation depend on variation of c-Myc protein levels. We show that proliferation rates, the number of cells in S-phase, and cell size increased in a dose-dependent manner in response to increasing c-Myc levels. Likewise, the mRNA levels of c-Myc responsive genes s...

  15. A smallest 6 kda metalloprotease, mini-matrilysin, in living world: a revolutionary conserved zinc-dependent proteolytic domain- helix-loop-helix catalytic zinc binding domain (ZBD

    Directory of Open Access Journals (Sweden)

    Yu Wei-Hsuan

    2012-05-01

    Full Text Available Abstract Background The Aim of this study is to study the minimum zinc dependent metalloprotease catalytic folding motif, helix B Met loop-helix C, with proteolytic catalytic activities in metzincin super family. The metzincin super family share a catalytic domain consisting of a twisted five-stranded β sheet and three long α helices (A, B and C. The catalytic zinc is at the bottom of the cleft and is ligated by three His residues in the consensus sequence motif, HEXXHXXGXXH, which is located in helix B and part of the adjacent Met turn region. An interesting question is - what is the minimum portion of the enzyme that still possesses catalytic and inhibitor recognition?” Methods We have expressed a 60-residue truncated form of matrilysin which retains only the helix B-Met turn-helix C region and deletes helix A and the five-stranded β sheet which form the upper portion of the active cleft. This is only 1/4 of the full catalytic domain. The E. coli derived 6 kDa MMP-7 ZBD fragments were purified and refolded. The proteolytic activities were analyzed by Mca-Pro-Leu-Gly-Leu-Dpa-Ala-Arg-NH2 peptide assay and CM-transferrin zymography analysis. SC44463, BB94 and Phosphoramidon were computationally docked into the 3day structure of the human MMP7 ZBD and TAD and thermolysin using the docking program GOLD. Results This minimal 6 kDa matrilysin has been refolded and shown to have proteolytic activity in the Mca-Pro-Leu-Gly-Leu-Dpa-Ala-Arg-NH2 peptide assay. Triton X-100 and heparin are important factors in the refolding environment for this mini-enzyme matrilysin. This minienzyme has the proteolytic activity towards peptide substrate, but the hexamer and octamer of the mini MMP-7 complex demonstrates the CM-transferrin proteolytic activities in zymographic analysis. Peptide digestion is inhibited by SC44463, specific MMP7 inhibitors, but not phosphorimadon. Interestingly, the mini MMP-7 can be processed by autolysis and producing ~ 6 ~ 7 kDa fragments. Thus, many of the functions of the enzyme are retained indicating that the helix B-Met loop-helix C is the minimal functional “domain” found to date for the matrixin family. Conclusions The helix B-Met loop-helix C folding conserved in metalloprotease metzincin super family is able to facilitate proteolytic catalysis for specific substrate and inhibitor recognition. The autolysis processing and producing 6 kDa mini MMP-7 is the smallest metalloprotease in living world.

  16. A smallest 6 kda metalloprotease, mini-matrilysin, in living world: a revolutionary conserved zinc-dependent proteolytic domain- helix-loop-helix catalytic zinc binding domain (ZBD).

    Science.gov (United States)

    Yu, Wei-Hsuan; Huang, Po-Tsang; Lou, Kuo-Long; Yu, Shuan-Su C; Lin, Chen

    2012-05-29

    The Aim of this study is to study the minimum zinc dependent metalloprotease catalytic folding motif, helix B Met loop-helix C, with proteolytic catalytic activities in metzincin super family. The metzincin super family share a catalytic domain consisting of a twisted five-stranded β sheet and three long α helices (A, B and C). The catalytic zinc is at the bottom of the cleft and is ligated by three His residues in the consensus sequence motif, HEXXHXXGXXH, which is located in helix B and part of the adjacent Met turn region. An interesting question is - what is the minimum portion of the enzyme that still possesses catalytic and inhibitor recognition?" We have expressed a 60-residue truncated form of matrilysin which retains only the helix B-Met turn-helix C region and deletes helix A and the five-stranded β sheet which form the upper portion of the active cleft. This is only 1/4 of the full catalytic domain. The E. coli derived 6 kDa MMP-7 ZBD fragments were purified and refolded. The proteolytic activities were analyzed by Mca-Pro-Leu-Gly-Leu-Dpa-Ala-Arg-NH2 peptide assay and CM-transferrin zymography analysis. SC44463, BB94 and Phosphoramidon were computationally docked into the 3 day structure of the human MMP7 ZBD and TAD and thermolysin using the docking program GOLD. This minimal 6 kDa matrilysin has been refolded and shown to have proteolytic activity in the Mca-Pro-Leu-Gly-Leu-Dpa-Ala-Arg-NH2 peptide assay. Triton X-100 and heparin are important factors in the refolding environment for this mini-enzyme matrilysin. This minienzyme has the proteolytic activity towards peptide substrate, but the hexamer and octamer of the mini MMP-7 complex demonstrates the CM-transferrin proteolytic activities in zymographic analysis. Peptide digestion is inhibited by SC44463, specific MMP7 inhibitors, but not phosphorimadon. Interestingly, the mini MMP-7 can be processed by autolysis and producing ~ 6 ~ 7 kDa fragments. Thus, many of the functions of the enzyme are retained indicating that the helix B-Met loop-helix C is the minimal functional "domain" found to date for the matrixin family. The helix B-Met loop-helix C folding conserved in metalloprotease metzincin super family is able to facilitate proteolytic catalysis for specific substrate and inhibitor recognition. The autolysis processing and producing 6 kDa mini MMP-7 is the smallest metalloprotease in living world.

  17. A versatile polypeptide platform for integrated recognition and reporting: affinity arrays for protein-ligand interaction analysis.

    Science.gov (United States)

    Enander, Karin; Dolphin, Gunnar T; Liedberg, Bo; Lundström, Ingemar; Baltzer, Lars

    2004-05-17

    A molecular platform for protein detection and quantification is reported in which recognition has been integrated with direct monitoring of target-protein binding. The platform is based on a versatile 42-residue helix-loop-helix polypeptide that dimerizes to form four-helix bundles and allows site-selective modification with recognition and reporter elements on the side chains of individually addressable lysine residues. The well-characterized interaction between the model target-protein carbonic anhydrase and its inhibitor benzenesulfonamide was used for a proof-of-concept demonstration. An affinity array was designed where benzenesulfonamide derivatives with aliphatic or oligoglycine spacers and a fluorescent dansyl reporter group were introduced into the scaffold. The affinities of the array members for human carbonic anhydrase II (HCAII) were determined by titration with the target protein and were found to be highly affected by the properties of the spacers (dissociation constant Kd=0.02-3 microM). The affinity of HCAII for acetazolamide (Kd=4 nM) was determined in a competition experiment with one of the benzenesulfonamide array members to address the possibility of screening substance libraries for new target-protein binders. Also, successful affinity discrimination between different carbonic anhydrase isozymes highlighted the possibility of performing future isoform-expression profiling. Our platform is predicted to become a flexible tool for a variety of biosensor and protein-microarray applications within biochemistry, diagnostics and pharmaceutical chemistry.

  18. Protein Folding: Search for Basic Physical Models

    Directory of Open Access Journals (Sweden)

    Ivan Y. Torshin

    2003-01-01

    Full Text Available How a unique three-dimensional structure is rapidly formed from the linear sequence of a polypeptide is one of the important questions in contemporary science. Apart from biological context of in vivo protein folding (which has been studied only for a few proteins, the roles of the fundamental physical forces in the in vitro folding remain largely unstudied. Despite a degree of success in using descriptions based on statistical and/or thermodynamic approaches, few of the current models explicitly include more basic physical forces (such as electrostatics and Van Der Waals forces. Moreover, the present-day models rarely take into account that the protein folding is, essentially, a rapid process that produces a highly specific architecture. This review considers several physical models that may provide more direct links between sequence and tertiary structure in terms of the physical forces. In particular, elaboration of such simple models is likely to produce extremely effective computational techniques with value for modern genomics.

  19. Zn-binding AZUL domain of human ubiquitin protein ligase Ube3A

    Energy Technology Data Exchange (ETDEWEB)

    Lemak, Alexander; Yee, Adelinda [University of Toronto, and Northeast Structural Genomics Consortium, Ontario Cancer Institute, Campbell Family Cancer Research Institute and Department of Medical Biophysics (Canada); Bezsonova, Irina, E-mail: bezsonova@uchc.edu [University of Connecticut Health Center, Department of Molecular Microbial and Structural Biology (United States); Dhe-Paganon, Sirano, E-mail: sirano.dhepaganon@utoronto.ca [University of Toronto, Structural Genomics Consortium (Canada); Arrowsmith, Cheryl H., E-mail: carrow@uhnresearch.ca [University of Toronto, and Northeast Structural Genomics Consortium, Ontario Cancer Institute, Campbell Family Cancer Research Institute and Department of Medical Biophysics (Canada)

    2011-09-15

    Ube3A (also referred to as E6AP for E6 Associated Protein) is a E3 ubiquitin-protein ligase implicated in the development of Angelman syndrome by controlling degradation of synaptic protein Arc and oncogenic papilloma virus infection by controlling degradation of p53. This article describe the solution NMR structure of the conserved N-terminal domain of human Ube3A (residues 24-87) that contains two residues (Cys44 and Arg62) found to be mutated in patients with Angelman syndrome. The structure of this domain adopts a novel Zn-binding fold we called AZUL (Amino-terminal Zn-finger of Ube3a Ligase). The AZUL domain has a helix-loop-helix architecture with a Zn ion coordinated by four Cys residues arranged in Cys-X{sub 4}-Cys-X{sub 4}-Cys-X{sub 28}-Cys motif. Three of the Zn-bound residues are located in a 23-residue long and well structured loop that connects two {alpha}-helicies.

  20. Zn-binding AZUL domain of human ubiquitin protein ligase Ube3A

    International Nuclear Information System (INIS)

    Lemak, Alexander; Yee, Adelinda; Bezsonova, Irina; Dhe-Paganon, Sirano; Arrowsmith, Cheryl H.

    2011-01-01

    Ube3A (also referred to as E6AP for E6 Associated Protein) is a E3 ubiquitin-protein ligase implicated in the development of Angelman syndrome by controlling degradation of synaptic protein Arc and oncogenic papilloma virus infection by controlling degradation of p53. This article describe the solution NMR structure of the conserved N-terminal domain of human Ube3A (residues 24-87) that contains two residues (Cys44 and Arg62) found to be mutated in patients with Angelman syndrome. The structure of this domain adopts a novel Zn-binding fold we called AZUL (Amino-terminal Zn-finger of Ube3a Ligase). The AZUL domain has a helix-loop-helix architecture with a Zn ion coordinated by four Cys residues arranged in Cys-X 4 -Cys-X 4 -Cys-X 28 -Cys motif. Three of the Zn-bound residues are located in a 23-residue long and well structured loop that connects two α-helicies.

  1. E2A proteins are required for proper B cell development and initiation of immunoglobulin gene rearrangements

    NARCIS (Netherlands)

    Bain, G.; Maandag, E. C.; Izon, D. J.; Amsen, D.; Kruisbeek, A. M.; Weintraub, B. C.; Krop, I.; Schlissel, M. S.; Feeney, A. J.; van Roon, M.

    1994-01-01

    E12 and E47 are two helix-loop-helix transcription factors that arise by alternative splicing of the E2A gene. Both have been implicated in the regulation of immunoglobulin gene expression. We have now generated E2A (-/-) mice by gene targeting. E2A-null mutant mice fail to generate mature B cells.

  2. Specific interaction of central nervous system myelin basic protein with lipids effects of basic protein on glucose leakage from liposomes

    NARCIS (Netherlands)

    Gould, R.M.; London, Y.

    1972-01-01

    The leakage from liposomes preloaded with glucose was continuously monitored in a Perkin-Elmer Model 356 dual beam spectrophotometer using an enzyme-linked assay system. The central nervous system myelin basic protein (A1 protein) caused a 3–4-fold increase in the rate of leakage from liposomes

  3. Comparative aspects of basic chromatin proteins in dinoflagellates.

    Science.gov (United States)

    Rizzo, P J

    1981-01-01

    Previous work on histone-like proteins in dinoflagellates is summarized, together with some new data to give an overview of basic proteins in these algae. The first two dinoflagellates studied were both found to contain one major acid-soluble protein that migrated to the same position in acidic-urea gels. When several other genera were studied however, it became apparent that the histone-like proteins from different dinoflagellates were similar but not identical. In view of the great diversity of living dinoflagellates it is speculated that further differences in dinoflagellate basic chromatin proteins will be revealed. Electrophoretic data from the eukaryotic (endosymbiont) nucleus of Peridinium balticum showed the presence of five major components. It is speculated that two of these proteins represent an H1-like doublet and two others correspond to the highly conserved histones H3 and H4. The fifth component is a new histone that may substitute for H2A and H2B in the nucleosome. Because histones and nucleosomes are present in all higher organisms but completely lacking in procaryotes, studies on basic proteins in dinoflagellates will provides insights into the evolution of histones and eucaryotic chromatin organization.

  4. A Functional Genetic Screen Identifies TFE3 as a Gene That Confers Resistance to the Anti-proliferative Effects of the Retinoblastoma Protein and Transforming Growth Factor-β

    NARCIS (Netherlands)

    Nijman, S.M.B.; Hijmans, E.M.; Messaoudi, S. El; Dongen, M.M.; Sardet, C.; Bernards, R.A.

    2006-01-01

    The helix-loop-helix transcription factor TFE3 has been suggested to play a role in the control of cell growth by acting as a binding partner of transcriptional regulators such as E2F3, SMAD3, and LEF-1 (1–4). Furthermore, translocations/TFE3 fusions have been directly implicated in tumorigenesis

  5. Eosinophil cationic protein stimulates and major basic protein inhibits airway mucus secretion

    DEFF Research Database (Denmark)

    Lundgren, J D; Davey, R T; Lundgren, B

    1991-01-01

    . Crude extracts from isolated EO granules also stimulated RGC release, suggesting that a granular protein might be responsible. Three proteins derived from EO granules, EO-derived neurotoxin, EO cationic protein (ECP), and major basic protein (MBP) were separated by sequential sizing and affinity...

  6. SPEECHLESS integrates brassinosteroid and stomata signalling pathways.

    NARCIS (Netherlands)

    Gudesblat, G.E.; Schneider-Pizon, J.; Betti, C.; Mayerhofer, J.; Vanhoutte, I.; Dongen, van W.M.A.M.; Boeren, J.A.; Zhiponova, M.; Vries, de S.C.; Jonak, C.; Russinova, E.T.

    2012-01-01

    Stomatal formation is regulated by multiple developmental and environmental signals, but how these signals are integrated to control this process is not fully understood1. In Arabidopsis thaliana, the basic helix-loop-helix transcription factor SPEECHLESS (SPCH) regulates the entry, amplifying and

  7. Discovery of the porcine NGN3 gene and testing its endocrine function in the pig

    Science.gov (United States)

    Neurogenin 3 (NGN3) is a member of the basic helix-loop-helix transcription factor family. NGN3 is both necessary and sufficient to drive endocrine differentiation in the developing pancreas in mouse and humans. Until now, the sequence for NGN3 eluded discovery despite completion of the pig genome a...

  8. Enhancer mutations of Akv murine leukemia virus inhibit the induction of mature B-cell lymphomas and shift disease specificity towards the more differentiated plasma cell stage

    DEFF Research Database (Denmark)

    Sørensen, Karina Dalsgaard; Kunder, Sandra; Quintanilla-Martinez, Leticia

    2007-01-01

    receptor, Ets, Runx, or basic helix-loop-helix transcription factors in the proviral U3 region, however, shifted disease induction to almost exclusively PCPs, but had no major influence on tumor latency periods. Southern analysis of immunoglobulin rearrangements and ecotropic provirus integration patterns...

  9. A new role for E12/E47 in the repression of E-cadherin expression and epithelial-mesenchymal transitions

    DEFF Research Database (Denmark)

    Perez-Moreno, M A; Locascio, A; Rodrigo, I

    2001-01-01

    Down-regulation of E-cadherin expression is a determinant of tumor cell invasiveness, an event frequently associated with epithelial-mesenchymal transitions. Here we show that the mouse E12/E47 basic helix-loop-helix transcription factor (the E2A gene product) acts as a repressor of E-cadherin ex...

  10. Cardia bifida, defective heart development and abnormal neural crest migration in embryos lacking hypoxia-inducible factor-1alpha

    NARCIS (Netherlands)

    Compernolle, Veerle; Brusselmans, Koen; Franco, Diego; Moorman, Antoon; Dewerchin, Mieke; Collen, Désiré; Carmeliet, Peter

    2003-01-01

    OBJECTIVES: Previous studies have revealed the essential role of hypoxia-inducible factor-1alpha (HIF-1alpha), a basic helix-loop-helix transcription factor, in cardiovascular development. We attempted to further characterize the underlying mechanisms resulting in abnormal cardiogenesis and

  11. Molecular cloning, sequence analysis and tissue expression of ...

    African Journals Online (AJOL)

    Dama cattle breeds was conducted, as well as a molecular cloning of the gene transcript from bovine placenta. Four site-specific motifs were identified in the basic helix-loop-helix (bHLH) domain that are highly conserved in cattle, humans and ...

  12. Transcriptional targets of TWIST1 in the cranial mesoderm regulate cell-matrix interactions and mesenchyme maintenance

    NARCIS (Netherlands)

    Bildsoe, Heidi; Fan, Xiaochen; Wilkie, Emilie E.; Ashoti, Ator; Jones, Vanessa J.; Power, Melinda; Qin, Jing; Wang, Junwen; Tam, Patrick P L; Loebel, David A F

    2016-01-01

    TWIST1, a basic helix-loop-helix transcription factor is essential for the development of cranial mesoderm and cranial neural crest-derived craniofacial structures. We have previously shown that, in the absence of TWIST1, cells within the cranial mesoderm adopt an abnormal epithelial configuration

  13. Anthocyanini of petunia controls pigment synthesis, vacuolar pH, and seed coat development by genetically distinct mechanisms

    NARCIS (Netherlands)

    Spelt, C.E.; Quattrocchio, F.M.; Mol, J.N.M.; Koes, R.E.

    2002-01-01

    ANTHOCYANIN1 (AN1) of petunia is a transcription factor of the basic helix-loop-helix (bHLH) family that is required for the synthesis of anthocyanin pigments. Here, we show that AN1 controls additional aspects of cell differentiation: the acidification of vacuoles in petal cells, and the size and

  14. Translational control of TWIST1 expression in MCF-10A cell lines recapitulating breast cancer progression

    DEFF Research Database (Denmark)

    Nairismägi, Maarja-Liisa; Vislovukh, Andrii; Meng, Q

    2012-01-01

    TWIST1 is a highly conserved basic helix-loop-helix transcription factor that promotes epithelial–mesenchymal transition (EMT). Its misregulation has been observed in various types of tumors. Using the MCF-10A-series of cell lines that recapitulate the early stages of breast cancer formation...

  15. The window period of NEUROGENIN3 during human gestation

    NARCIS (Netherlands)

    R.J. Salisbury (Rachel J.); J. Blaylock (Jennifer); A.A. Berry (Andrew A.); R.E. Jennings (Rachel E.); R.R. de Krijger (Ronald); K.P. Hanley (Karen Piper); N.A. Hanley (Neil A)

    2014-01-01

    textabstractThe basic helix-loop-helix transcription factor, NEUROG3, is critical in causing endocrine commitment from a progenitor cell population in the developing pancreas. In human, NEUROG3 has been detected from 8 weeks postconception (wpc). However, the profile of its production and when it

  16. Measurement of guinea pig eosinophil major basic protein by radioimmunoassay

    International Nuclear Information System (INIS)

    Wassom, D.L.; Loegering, D.A.; Gleich, G.J.

    1979-01-01

    Guinea pig eosinophil major basic protein (MBP) was measured by radioimmunoassay (RIA) using 131 I-MBP. Two critical features of the assay were: (1) alkylation of the MBP with iodoacetamide prior to radioiodination and (2) inclusion of another basic protein, either protamine or histone, in the phosphate buffer. Freshly isolated non-alkylated MBP was immunologically deficient when compared to alkylated or reduced MBP, but its reactivity could be redtores by reduction with dithiothreitol and alkylation. Reduction and alkylation also restored the immunoreactivity of polymerized MBP. MBP levels were not elevated in sera from guinea pigs parasitized with Trichinella spiralis and having peripheral blood eosinophilia. Muscle extracts from Trichinella infected animals showed significantly higher levels of MBP activity than normal controls. MBP was measurable in extracts of untreated eosinophils, but reduction and alkylation of these extracts increased MBP activity several fold. The RIA permits detection of MBP in body fluids and tissues at levels as low as 2 ng./ml. The RIA is useful in assessing increased or decreased levels of MBP activity in samples from experimental animals when compared to samples from controls. (author)

  17. The structure of Aquifex aeolicus ribosomal protein S8 reveals a unique subdomain that contributes to an extremely tight association with 16S rRNA.

    Science.gov (United States)

    Menichelli, Elena; Edgcomb, Stephen P; Recht, Michael I; Williamson, James R

    2012-01-20

    The assembly of ribonucleoprotein complexes occurs under a broad range of conditions, but the principles that promote assembly and allow function at high temperature are poorly understood. The ribosomal protein S8 from Aquifex aeolicus (AS8) is unique in that there is a 41-residue insertion in the consensus S8 sequence. In addition, AS8 exhibits an unusually high affinity for the 16S ribosomal RNA, characterized by a picomolar dissociation constant that is approximately 26,000-fold tighter than the equivalent interaction from Escherichia coli. Deletion analysis demonstrated that binding to the minimal site on helix 21 occurred at the same nanomolar affinity found for other bacterial species. The additional affinity required the presence of a three-helix junction between helices 20, 21, and 22. The crystal structure of AS8 was solved, revealing the helix-loop-helix geometry of the unique AS8 insertion region, while the core of the molecule is conserved with known S8 structures. The AS8 structure was modeled onto the structure of the 30S ribosomal subunit from E. coli, suggesting the possibility that the unique subdomain provides additional backbone and side-chain contacts between the protein and an unpaired base within the three-way junction of helices 20, 21, and 22. Point mutations in the protein insertion subdomain resulted in a significantly reduced RNA binding affinity with respect to wild-type AS8. These results indicate that the AS8-specific subdomain provides additional interactions with the three-way junction that contribute to the extremely tight binding to ribosomal RNA. Copyright © 2011 Elsevier Ltd. All rights reserved.

  18. The Structure of Aquifex aeolicus Ribosomal Protein S8 Reveals a Unique Subdomain That Contributes to Extremely-Tight Association With 16S rRNA

    Science.gov (United States)

    Menichelli, Elena; Edgcomb, Stephen P.; Recht, Michael I.; Williamson, James R.

    2011-01-01

    The assembly of ribonucleoprotein complexes occurs in a broad range of conditions, but the principles that promote assembly and allow function at high temperature are poorly understood. The ribosomal protein S8 from the hyperthemophilic bacterium Aquifex aeolicus (AS8) is unique in that there is a 41 residue insertion in the consensus S8 sequence. In addition, AS8 exhibits an unusually-high affinity for the 16S ribosomal RNA (rRNA), characterized by a picomolar dissociation constant that is approximately 26,000 fold tighter than the equivalent interaction from Escherichia coli. Deletion analysis demonstrated that binding to the minimal helix 21 occurred at the same nanomolar affinity found for other bacterial species. The additional affinity required the presence of a three-helix junction between helices 20, 21, and 22. The crystal structure of AS8 was solved, revealing the helix-loop-helix geometry of the unique AS8 insertion region, while the core of the molecule is conserved with known S8 structures. The AS8 structure was modeled onto the structure of the 30S ribosomal subunit from E. coli, suggesting the possibility that the unique subdomain provides additional backbone and side-chain contacts between the protein and an unpaired base within the three-way junction of helices 20, 21, and 22. Point mutations in the protein insertion subdomain resulted in a significantly reduced RNA binding affinity with respect to wild-type AS8. These results indicate that the AS8-specific subdomain provides additional interactions with the three-way junction that contribute to the extremely tight binding to rRNA. PMID:22079365

  19. The calcium-modulated proteins, S100A1 and S100B, as potential regulators of the dynamics of type III intermediate filaments

    Directory of Open Access Journals (Sweden)

    M. Garbuglia

    1999-10-01

    Full Text Available The Ca2+-modulated, dimeric proteins of the EF-hand (helix-loop-helix type, S100A1 and S100B, that have been shown to inhibit microtubule (MT protein assembly and to promote MT disassembly, interact with the type III intermediate filament (IF subunits, desmin and glial fibrillary acidic protein (GFAP, with a stoichiometry of 2 mol of IF subunit/mol of S100A1 or S100B dimer and an affinity of 0.5-1.0 µM in the presence of a few micromolar concentrations of Ca2+. Binding of S100A1 and S100B results in inhibition of desmin and GFAP assemblies into IFs and stimulation of the disassembly of preformed desmin and GFAP IFs. S100A1 and S100B interact with a stretch of residues in the N-terminal (head domain of desmin and GFAP, thereby blocking the head-to-tail process of IF elongation. The C-terminal extension of S100A1 (and, likely, S100B represents a critical part of the site that recognizes desmin and GFAP. S100B is localized to IFs within cells, suggesting that it might have a role in remodeling IFs upon elevation of cytosolic Ca2+ concentration by avoiding excess IF assembly and/or promoting IF disassembly in vivo. S100A1, that is not localized to IFs, might also play a role in the regulation of IF dynamics by binding to and sequestering unassembled IF subunits. Together, these observations suggest that S100A1 and S100B may be regarded as Ca2+-dependent regulators of the state of assembly of two important elements of the cytoskeleton, IFs and MTs, and, potentially, of MT- and IF-based activities.

  20. Clockwork orange encodes a transcriptional repressor important for circadian-clock amplitude in Drosophila.

    Science.gov (United States)

    Lim, Chunghun; Chung, Brian Y; Pitman, Jena L; McGill, Jermaine J; Pradhan, Suraj; Lee, Jongbin; Keegan, Kevin P; Choe, Joonho; Allada, Ravi

    2007-06-19

    Gene transcription is a central timekeeping process in animal clocks. In Drosophila, the basic helix-loop helix (bHLH)-PAS transcription-factor heterodimer, CLOCK/CYCLE (CLK/CYC), transcriptionally activates the clock components period (per), timeless (tim), Par domain protein 1 (Pdp1), and vrille (vri), which feed back and regulate distinct features of CLK/CYC function. Microarray studies have identified numerous rhythmically expressed transcripts, some of which are potential direct CLK targets. Here we demonstrate a circadian function for one such target, a bHLH-Orange repressor, CG17100/CLOCKWORK ORANGE (CWO). cwo is rhythmically expressed, and levels are reduced in Clk mutants, suggesting that cwo is CLK activated in vivo. cwo mutants display reduced-amplitude molecular and behavioral rhythms with lengthened periods. Molecular analysis suggests that CWO acts, in part, by repressing CLK target genes. We propose that CWO acts as a transcriptional and behavioral rhythm amplifier.

  1. clockwork orange encodes a transcriptional repressor important for circadian clock amplitude in Drosophila

    Science.gov (United States)

    Lim, Chunghun; Chung, Brian Y.; Pitman, Jena L.; McGill, Jermaine J.; Pradhan, Suraj; Lee, Jongbin; Keegan, Kevin P.; Choe, Joonho; Allada, Ravi

    2007-01-01

    Summary Gene transcription is a central timekeeping process in animal clocks. In Drosophila, the basic helix-loop helix (bHLH)-PAS transcription factor heterodimer, CLOCK (CLK)/CYCLE(CYC) transcriptionally activates the clock components period (per), timeless (tim), Par domain protein 1 (Pdp1), and vrille (vri) that feedback and regulate distinct features of CLK/CYC function [1]. Microarray studies have identified numerous rhythmically expressed transcripts [2-7], some of which are potential direct CLK targets [7]. Here we demonstrate a circadian function for one such target, a bHLH-Orange repressor CG17100/CLOCKWORK ORANGE (CWO). cwo is rhythmically expressed and levels are reduced in Clk mutants, suggesting that cwo is CLK-activated in vivo. cwo mutants display reduced amplitude molecular and behavioral rhythms with lengthened periods. Molecular analysis suggests CWO acts, in part, by repressing CLK target genes. We propose that CWO acts as a transcriptional and behavioral rhythm amplifier. PMID:17555964

  2. Evolutionary aspects of variability in bHLH orthologous families: insights from the pearl oyster, Pinctada fucata.

    Science.gov (United States)

    Gyoja, Fuki; Satoh, Nori

    2013-10-01

    Basic helix-loop-helix (bHLH) transcription factors play significant roles in multiple biological processes in metazoan cells. In recent work, we showed that three orthologous HLH families, pearl, amber, and peridot, have apparently been lost in the Drosophila melanogaster, Caenorhabditis elegans, and Homo sapiens lineages. To further address the gain and loss of bHLH proteins during bilaterian evolution, we examined the genome of the pearl oyster, Pinctada fucata, which has recently been sequenced. We characterized the putative full set 65 bHLH genes and showed that genes previously categorized into the orthologous family PTFb, actually fall into two distinct orthologous families, 48-related-1 and 48-related-2. We also identified a novel orthologous family, clockwork orange. Based on these newly identified orthologous family members and on orphan bHLH factors, we propose that genes encoding bHLH factors in bilaterians are not as evolutionarily stable as previously thought.

  3. The Aryl Hydrocarbon Receptor Nuclear Translocator (ARNT/HIF-1β is Influenced by Hypoxia and Hypoxia-Mimetics

    Directory of Open Access Journals (Sweden)

    Matthias Wolff

    2013-09-01

    Full Text Available Background: The Aryl Hydrocarbon Receptor Nuclear Translocator (ARNT, HIF-1β is a member of the basic-Helix-Loop-Helix PER/ARNT/SIM (bHLH/PAS protein family and a vital transcriptional regulator regarding development and physiological adaptation processes. ARNT is discussed to be linked with cancer, and other diseases. ARNT is known to be translocated into the cell nucleus, where accumulation of the protein takes place. ARNT is a heterodimerisation partner of the xenobiotic ligand activated Aryl Hydrocarbon Receptor (AhR, the Single Minded proteins (SIM, the cardiovascular helix-loop-helix factor 1 and the Hypoxia Inducible Factor proteins (HIF-α. ARNT is obligatory for HIF-1, HIF-2 and HIF-3 binding to DNA. Whereas degradation of the HIF-α subunits is suppressed by hypoxia, ARNT is generally regarded as constitutively expressed in excess within the cell, and stabilisation is commonly thought to be oxygen-independent. However, we provide evidence that the regulation of ARNT is far more complex. The aim of our study was to reevaluate the regulation of ARNT expression. Methods: We examined cell lines of different origin like MCF-7 and T47D (human breast cancer, HeLa (human cervix carcinoma, Hep3B and HepG2 (human hepatoma, Kelly (human neuroblastoma, REPC (human kidney and Cos7 (primary primate kidney cells. We used immunoblot analysis, densitometry, RT-PCR and transient transfection. Results and Conclusion: Our results show that ARNT protein levels are influenced by hypoxia and hypoxia mimetics such as cobalt(II-chloride (CoCl2 and dimethyloxalylglycine (DMOG in a cell line specific manner. We demonstrate that this effect might be triggered by HIF-1α which plays an important role in the process of stabilizing ARNT in hypoxia.

  4. Genome-wide and comparative analysis of bHLH38, bHLH39, bHLH100 and bHLH101 genes in Arabidopsis, tomato, rice, soybean and maize: insights into iron (Fe) homeostasis.

    Science.gov (United States)

    Kurt, Fırat; Filiz, Ertugrul

    2018-03-15

    Iron (Fe) is an essential element for plant life. Its deficiency impedes growth and development and excessive iron can cause the toxic effect via the Fenton reaction. Thus, plants have developed various mechanisms to acquire, distribute and utilize Fe for the maintenance of their iron homeostasis at cellular and systemic levels. A basic helix-loop-helix (bHLH) transcription factor family plays essential roles in many regulatory and development processes in plants. In this study, we aimed to understand the roles of bHLH38, bHLH39, bHLH100 and bHLH101 genes for Fe homeostasis in Arabidopsis, tomato, rice, soybean and maize species by using bioinformatics approaches. The gene/protein sequence analyses of these genes demonstrated that all bHLH proteins comprised helix-loop-helix DNA binding domain (PF00010) with varied exon numbers between 2 and 13. The phylogenetic analysis did not reveal a clear distinction between monocot and dicot plants. A total of 61 cis-elements were found in promotor sequences, including biotic and abiotic stress responsiveness, hormone responsiveness, and tissue specific expressions. The some structural divergences were identified in predicted 3D structures of bHLH proteins with different channels numbers. The co-expression network analysis demonstrated that bHLH39 and bHLH101 played more important roles in Fe regulation in Arabidopsis. The digital expression analysis showed various expression profiles of bHLH genes which were identified in developmental stages, anatomical parts, and perturbations. Particularly, bHLH39 and bHLH101 genes were found to be more active genes in Fe homeostasis. As a result, our findings can contribute to understanding of bHLH38, bHLH39, bHLH100 and bHLH101 genes in Fe homeostasis in plants.

  5. The Antirrhinum AmDEL gene enhances flavonoids accumulation and salt and drought tolerance in transgenic Arabidopsis.

    Science.gov (United States)

    Wang, Feibing; Zhu, Hong; Kong, Weili; Peng, Rihe; Liu, Qingchang; Yao, Quanhong

    2016-07-01

    A basic helix-loop-helix (bHLH) transcription factor gene from Antirrhinum, AmDEL , increases flavonoids accumulation and enhances salt and drought tolerance via up-regulating flavonoid biosynthesis, proline biosynthesis and ROS scavenging genes in transgenic Arabidopsis. In plants, transcriptional regulation is the most important tools for increasing flavonoid biosynthesis. The AmDEL gene, as a basic helix-loop-helix transcription factor gene from Antirrhinum, has been shown to increase flavonoids accumulation in tomato. However, its role in tolerance to abiotic stresses has not yet been investigated. In this study, the codon-optimized AmDEL gene was chemically synthesized. Subcellular localization analysis in onion epidermal cells indicated that AmDEL protein was localized to the nucleus. Expression analysis in yeast showed that the full length of AmDEL exhibited transcriptional activation. Overexpression of AmDEL significantly increased flavonoids accumulation and enhanced salt and drought tolerance in transgenic Arabidopsis plants. Real-time quantitative PCR analysis showed that overexpression of AmDEL resulted in the up-regulation of genes involved in flavonoid biosynthesis, proline biosynthesis and ROS scavenging under salt and drought stresses. Meanwhile, Western blot and enzymatic analyses showed that the activities of phenylalanine ammonia lyase, chalcone isomerase, dihydroflavonol reductase, pyrroline-5-carboxylate synthase, superoxide dismutase and peroxidase were also increased. Further components analyses indicated that the significant increase of proline and relative water content and the significant reduction of H2O2 and malonaldehyde content were observed under salt and drought stresses. In addition, the rates of electrolyte leakage and water loss were reduced in transgenic plants. These findings imply functions of AmDEL in accumulation of flavonoids and tolerance to salt and drought stresses. The AmDEL gene has the potential to be used to increase

  6. BASIC

    DEFF Research Database (Denmark)

    Hansen, Pelle Guldborg; Schmidt, Karsten

    2017-01-01

    BPP. Tilgangen består dels af den overordnede proces-model BASIC og dels af et iboende framework, ABCD, der er en model for systematisk adfærdsanalyse, udvikling, test og implementering af adfærdsrettede løsningskoncepter. Den samlede model gør det muligt for forskere såvel som offentligt ansatte...

  7. Dietary proteins in humans: basic aspects and consumption in Switzerland.

    Science.gov (United States)

    Guigoz, Yves

    2011-03-01

    This introductory review gives an overview on protein metabolism, and discusses protein quality, sources, and requirements as well as the results from recent studies on Swiss spontaneous protein consumption. To assess protein quality in protein mixes and foods, the "protein digestibility-corrected amino acid score" (PDCAAS) is presented as a valuable tool in addition to the biological value (BV). Considering protein intake recommendations, the lower limit recommended has been defined according to the minimal amount needed to maintain short-term nitrogen balance in healthy people with moderate activity. Evaluation of intakes in Switzerland from food consumption data is about 90 g/day of protein per person. Two-thirds of proteins consumed in Switzerland are animal proteins with high biological value [meat and meat products (28 %), milk and dairy products (28 %), fish (3 %), and eggs (3 %)] and about 1/3 of proteins are of plant origin (25 % of cereals, 3 - 4 % of vegetables). Actual spontaneous protein consumption in Switzerland by specific groups of subjects is well within the actual recommendations (10 - 20 % of energy) with only the frail elderly being at risk of not covering their requirements for protein.

  8. Endogenous phosphorylation of basic protein in myelin of varying degrees of compaction

    International Nuclear Information System (INIS)

    Schulz, P.; Moscarello, M.A.; Cruz, T.F.

    1988-01-01

    Fractions containing myelin of varying degrees of compaction were prepared from human white matter. Protein kinase activity in these fractions was measured by using both endogenous and exogenous myelin basic protein (MBP) as substrates. In both cases, less compact myelin fractions possessed higher levels of protein kinase activity than the compact myelin fraction. In addition, the specific activity of phosphorylated basic protein was greater in the loosely compacted fractions than in compact multilamellar myelin. When basic protein in compact myelin or the myelin fractions was phosphorylated by the endogenous kinase, approximately 70% of the [ 32 P]phosphate was incorporated at a single site, identified as Ser-102. The remaining 30% was found in three other minor sites. Electron microscopy of less compact myelin showed it was composed of fewer lamellae which correlated with a relative decrease in the proportion of cationic charge isomers (microheteromers) when MBP was subjected to gel electrophoresis at alkaline pH. The shift in charge microheterogeneity of basic protein to the less cationic isomers in the less compact myelin fractions correlated with an increase in protein kinase activity and a greater specific activity of phosphorylated basic protein

  9. International Union of Basic and Clinical Pharmacology. XCIV. Adhesion G protein-coupled receptors

    DEFF Research Database (Denmark)

    Hamann, Jörg; Aust, Gabriela; Araç, Demet

    2015-01-01

    The Adhesion family forms a large branch of the pharmacologically important superfamily of G protein-coupled receptors (GPCRs). As Adhesion GPCRs increasingly receive attention from a wide spectrum of biomedical fields, the Adhesion GPCR Consortium, together with the International Union of Basic...

  10. Ox peripheral nerve myelin membrane. Purification and partial characterization of two basic proteins

    NARCIS (Netherlands)

    London, Y.

    1971-01-01

    Two basic proteins were purified from the peripheral nervous system. The isolation was achieved by (1) delipidation with chloroform-butanol mixtures, dry acetone, and dry ether, (2) acid extraction at pH 2 and then (3) dialysis against distilled water, lyophilization, and solubilization in pH-10.7

  11. Computational Methods for Protein Structure Prediction and Modeling Volume 1: Basic Characterization

    CERN Document Server

    Xu, Ying; Liang, Jie

    2007-01-01

    Volume one of this two volume sequence focuses on the basic characterization of known protein structures as well as structure prediction from protein sequence information. The 11 chapters provide an overview of the field, covering key topics in modeling, force fields, classification, computational methods, and struture prediction. Each chapter is a self contained review designed to cover (1) definition of the problem and an historical perspective, (2) mathematical or computational formulation of the problem, (3) computational methods and algorithms, (4) performance results, (5) existing software packages, and (6) strengths, pitfalls, challenges, and future research directions.

  12. Myelin basic protein induces neuron-specific toxicity by directly damaging the neuronal plasma membrane.

    Directory of Open Access Journals (Sweden)

    Jie Zhang

    Full Text Available The central nervous system (CNS insults may cause massive demyelination and lead to the release of myelin-associated proteins including its major component myelin basic protein (MBP. MBP is reported to induce glial activation but its effect on neurons is still little known. Here we found that MBP specifically bound to the extracellular surface of the neuronal plasma membrane and induced neurotoxicity in vitro. This effect of MBP on neurons was basicity-dependent because the binding was blocked by acidic lipids and competed by other basic proteins. Further studies revealed that MBP induced damage to neuronal membrane integrity and function by depolarizing the resting membrane potential, increasing the permeability to cations and other molecules, and decreasing the membrane fluidity. At last, artificial liposome vesicle assay showed that MBP directly disturbed acidic lipid bilayer and resulted in increased membrane permeability. These results revealed that MBP induces neurotoxicity through its direct interaction with acidic components on the extracellular surface of neuronal membrane, which may suggest a possible contribution of MBP to the pathogenesis in the CNS disorders with myelin damage.

  13. Mini review roles of the bZIP gene family in rice.

    Science.gov (United States)

    E, Z G; Zhang, Y P; Zhou, J H; Wang, L

    2014-04-16

    The basic leucine zipper (bZIP) genes encode transcription factors involved in the regulation of various biological processes. Similar to WRKY, basic helix-loop-helix, and several other groups of proteins, the bZIP proteins form a superfamily of transcription factors that mediate plant stress responses. In this review, we present the roles of bZIP proteins in multiple biological processes that include pathogen defense; responses to abiotic stresses; seed development and germination; senescence; and responses to salicylic, jasmonic, and abscisic acids in rice. We also examined the characteristics of the bZIP proteins and their genetic composition. To ascertain the evolutionary changes in and functions of this supergene family, we performed an exhaustive comparison among the 89 rice bZIP genes that were previously described and those more recently listed in the MSU Rice Genome Annotation Project Database using a Hidden Markov Model. We excluded 3 genes from the list, resulting in a total of 86 bZIP genes in japonica rice.

  14. Freeze-drying of proteins in glass solids formed by basic amino acids and dicarboxylic acids.

    Science.gov (United States)

    Izutsu, Ken-ichi; Kadoya, Saori; Yomota, Chikako; Kawanishi, Toru; Yonemochi, Etsuo; Terada, Katsuhide

    2009-01-01

    The purpose of this study was to produce and characterize glass-state amorphous solids containing amino acids and organic acids that protect co-lyophilized proteins. Thermal analysis of frozen solutions containing a basic amino acid (e.g., L-arginine, L-lysine, L-histidine) and a hydroxy di- or tricarboxylic acid (e.g., citric acid, L-tartaric acid, DL-malic acid) showed glass transition of maximally freeze-concentrated solute at temperatures (T'g) significantly higher than those of the individual solute solutions. Mixing of the amino acid with some dicarboxylic acids (e.g., oxalic acid) also suggested an upward shift of the transition temperature. Contrarily, combinations of the amino acid with monocarboxylic acids (e.g., acetic acid) had T'gs between those of the individual solute solutions. Co-lyophilization of the basic amino acids and citric acid or L-tartaric acid resulted in amorphous solids that have glass transition temperatures (Tg) higher than the individual components. Mid- and near-infrared analysis indicated altered environment around the functional groups of the consisting molecules. Some of the glass-state excipient combinations protected an enzyme (lactate dehydrogenase, LDH) from inactivation during freeze-drying. The glass-state excipient combinations formed by hydrogen-bonding and electrostatic interaction network would be potent alternative to stabilize therapeutic proteins in freeze-dried formulations.

  15. The bHLH Factors Extramacrochaetae and Daughterless Control Cell Cycle in Drosophila Imaginal Discs through the Transcriptional Regulation of the cdc25 Phosphatase string

    Science.gov (United States)

    Andrade-Zapata, Irene; Baonza, Antonio

    2014-01-01

    One of the major issues in developmental biology is about having a better understanding of the mechanisms that regulate organ growth. Identifying these mechanisms is essential to understand the development processes that occur both in physiological and pathological conditions, such as cancer. The E protein family of basic helix-loop helix (bHLH) transcription factors, and their inhibitors the Id proteins, regulate cell proliferation in metazoans. This notion is further supported because the activity of these factors is frequently deregulated in cancerous cells. The E protein orthologue Daughterless (Da) and the Id orthologue Extramacrochaetae (Emc) are the only members of these classes of bHLH proteins in Drosophila. Although these factors are involved in controlling proliferation, the mechanism underlying this regulatory activity is poorly understood. Through a genetic analysis, we show that during the development of epithelial cells in the imaginal discs, the G2/M transition, and hence cell proliferation, is controlled by Emc via Da. In eukaryotic cells, the main activator of this transition is the Cdc25 phosphatase, string. Our genetic analyses reveal that the ectopic expression of string in cells with reduced levels of Emc or high levels of Da is sufficient to rescue the proliferative defects seen in these mutant cells. Moreover, we present evidence demonstrating a role of Da as a transcriptional repressor of string. Taken together, these findings define a mechanism through which Emc controls cell proliferation by regulating the activity of Da, which transcriptionally represses string. PMID:24651265

  16. Characterization of a novel class II bHLH transcription factor from the black widow spider, Latrodectus hesperus, with silk-gland restricted patterns of expression.

    Science.gov (United States)

    Kohler, Kristin; Thayer, William; Le, Trang; Sembhi, Amardeep; Vasanthavada, Keshav; Moore, Anne M F; Vierra, Craig A

    2005-06-01

    Members of the basic helix-loop-helix (bHLH) family are required for a number of different developmental pathways, including lymphopoiesis, myogenesis, neurogenesis, and sex determination. Screening a cDNA library prepared from silk-producing glands of the black widow spider, we have identified a new bHLH transcription factor named SGSF. Within the bHLH region, SGSF showed considerable conservation with other HLH proteins, including Drosophila melanogaster achaete and scute, as well as three HLH proteins identified by gene prediction programs. The expression pattern of SGSF was restricted to a subset of silk-producing glands, which include the tubuliform and major ampullate glands. SGSF was capable of binding an E-box element as a heterodimer with the E protein, E47, but was unable to bind this motif as a homodimer. SGSF was demonstrated to be a nuclear transcription factor capable of attenuating the transactivation of E47 homodimers in mammalian cells. SGSF represents the first example of a silk gland-restricted bHLH protein, and its expression pattern suggests that SGSF plays a role in regulating differentiation of cells in the spider that control silk gland formation or egg case silk gene expression.

  17. Characterization of FaSPT, a SPATULA gene encoding a bHLH transcriptional factor from the non-climacteric strawberry fruit.

    Science.gov (United States)

    Tisza, Viktória; Kovács, László; Balogh, Andrea; Heszky, László; Kiss, Erzsébet

    2010-01-01

    The involvement of basic-helix-loop-helix (bHLH) transcription factors in essential physiological and developmental processes is well established. Although a lot of animal bHLH proteins were characterized functionally, much less bHLHs of plant origin have been studied so far. Using a cDNA-AFLP approach, a ripening-related SPATULA gene was identified from strawberry fruit (Fragaria × ananassa Duch.), which encodes a bHLH protein. It is an orthologue of an Arabidopsis SPATULA protein, which has an important role in carpel and fruit development. Our experiments revealed that FaSPT is repressed by auxin in green fruits, and shows different expression patterns in receptacles at various stages of fruit ripening by ethylene treatment. Moreover, we applied a reverse genetic tool to elucidate the in planta function of FaSPT in early fruit development. To our knowledge, this work is the first report for the characterization of a SPATULA gene from a non-climacteric fruit. Copyright © 2010 Elsevier Masson SAS. All rights reserved.

  18. Out of the mouths of plants: the molecular basis of the evolution and diversity of stomatal development.

    Science.gov (United States)

    Peterson, Kylee M; Rychel, Amanda L; Torii, Keiko U

    2010-02-01

    Stomata are microscopic valves on the plant epidermis that played a critical role in the evolution of land plants. Studies in the model dicot Arabidopsis thaliana have identified key transcription factors and signaling pathways controlling stomatal patterning and differentiation. Three paralogous Arabidopsis basic helix-loop-helix proteins, SPEECHLESS (SPCH), MUTE, and FAMA, mediate sequential steps of cell-state transitions together with their heterodimeric partners SCREAM (SCRM) and SCRM2. Cell-cell signaling components, including putative ligands, putative receptors, and mitogen-activated protein kinase cascades, orient asymmetric cell divisions and prevent overproduction and clustering of stomata. The recent availability of genome sequence and reverse genetics tools for model monocots and basal land plants allows for the examination of the conservation of genes important in stomatal patterning and differentiation. Studies in grasses have revealed that divergence of SPCH-MUTE-FAMA predates the evolutionary split of monocots and dicots and that these proteins show conserved and novel roles in stomatal differentiation. By contrast, specific asymmetric cell divisions in Arabidopsis and grasses require unique molecular components. Molecular phylogenetic analysis implies potential conservation of signaling pathways and prototypical functions of the transcription factors specifying stomatal differentiation.

  19. Arabidopsis RSS1 Mediates Cross-Talk Between Glucose and Light Signaling During Hypocotyl Elongation Growth.

    Science.gov (United States)

    Singh, Manjul; Gupta, Aditi; Singh, Dhriti; Khurana, Jitendra P; Laxmi, Ashverya

    2017-11-23

    Plants possess exuberant plasticity that facilitates its ability to adapt and survive under challenging environmental conditions. The developmental plasticity largely depends upon cellular elongation which is governed by a complex network of environmental and phytohormonal signals. Here, we report role of glucose (Glc) and Glc-regulated factors in controlling elongation growth and shade response in Arabidopsis. Glc controls shade induced hypocotyl elongation in a dose dependent manner. We have identified a Glc repressed factor REGULATED BY SUGAR AND SHADE1 (RSS1) encoding for an atypical basic helix-loop-helix (bHLH) protein of unknown biological function that is required for normal Glc actions. Phenotype analysis of mutant and overexpression lines suggested RSS1 to be a negative regulator of elongation growth. RSS1 affects overall auxin homeostasis. RSS1 interacts with the elongation growth-promoting proteins HOMOLOG OF BEE2 INTERACTING WITH IBH 1 (HBI1) and BR ENHANCED EXPRESSION2 (BEE2) and negatively affects the transcription of their downstream targets such as YUCs, INDOLE-3-ACETIC ACID INDUCIBLE (IAAs), LONG HYPOCOTYL IN FAR-RED1 (HFR1), HOMEOBOX PROTEIN 2 (ATHB2), XYLOGLUCAN ENDOTRANSGLUCOSYLASE/HYDROLASES (XTHs) and EXPANSINS. We propose, Glc signals might maintain optimal hypocotyl elongation under multiple signals such as light, shade and phytohormones through the central growth regulatory bHLH/HLH module.

  20. The proform of eosinophil major basic protein: a new maternal serum marker for adverse pregnancy outcome

    DEFF Research Database (Denmark)

    Pihl, Kasper; Larsen, Torben; Rasmussen, Steen

    2009-01-01

    OBJECTIVE: To establish the first trimester serum levels of the proform of eosinophil major basic protein (proMBP) in pregnancies with adverse outcome. Furthermore, to determine the screening performance using proMBP alone and in combination with other first trimester markers. METHODS: A case-control...... study was conducted in a primary hospital setting. The proMBP concentration was measured in cases with small-for-gestational age (SGA) (n = 150), spontaneous preterm delivery (n = 88), preeclampsia (n = 40), gestational hypertension (n = 10) and in controls (n = 500). Concentrations were converted...... to multiples of the median (MoM) in controls and groups were compared using Mann-Whitney U-test. Logistic regression analysis was used to determine significant factors for predicting adverse pregnancy outcome. Screening performance was assessed using receiver operating characteristic curves. RESULTS: The pro...

  1. The RCSB Protein Data Bank: views of structural biology for basic and applied research and education.

    Science.gov (United States)

    Rose, Peter W; Prlić, Andreas; Bi, Chunxiao; Bluhm, Wolfgang F; Christie, Cole H; Dutta, Shuchismita; Green, Rachel Kramer; Goodsell, David S; Westbrook, John D; Woo, Jesse; Young, Jasmine; Zardecki, Christine; Berman, Helen M; Bourne, Philip E; Burley, Stephen K

    2015-01-01

    The RCSB Protein Data Bank (RCSB PDB, http://www.rcsb.org) provides access to 3D structures of biological macromolecules and is one of the leading resources in biology and biomedicine worldwide. Our efforts over the past 2 years focused on enabling a deeper understanding of structural biology and providing new structural views of biology that support both basic and applied research and education. Herein, we describe recently introduced data annotations including integration with external biological resources, such as gene and drug databases, new visualization tools and improved support for the mobile web. We also describe access to data files, web services and open access software components to enable software developers to more effectively mine the PDB archive and related annotations. Our efforts are aimed at expanding the role of 3D structure in understanding biology and medicine. © The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.

  2. Radioimmunoassay of the myelin basic protein in biological fluids, conditions improving sensitivity and specificity

    International Nuclear Information System (INIS)

    Delassalle, A.; Jacque, C.; Raoul, M.; Legrand, J.C.; Cesselin, F.; Drouet, J.

    1980-01-01

    The radioimmunoassay (RIA) for myelin basic protein (MBP) in biological fluids was reassessed in order to improve its sensitivity and eliminate some interferences. By using the pre-incubation technique and the charcoal-dextram-horse serum mixture for the separation step, the detection limit could be lowered to 200 pg/ml for cerebrospinal fluids (CSF), amniotic fluids (AF) and nervous tissue extracts and 600 pg/ml for sera. The RIA could be used directly on CSF, AF and nervous tissue extracts. Sera, however, had to be heated in citrate buffer at 100 0 C in order to discard interfering material. The present method is 10 to 20 times more sensitive than others previously published. Moreover, it can be applied to amniotic fluid. The biological fluids had to be promptly frozen to avoid degradation of MBP

  3. Acidic and basic solutions dissolve protein plugs made of lithostathine complicating choledochal cyst/pancreaticobiliary maljunction.

    Science.gov (United States)

    Kaneko, Kenitiro; Ono, Yasuyuki; Tainaka, Takahisa; Sumida, Wataru; Ando, Hisami

    2009-07-01

    Symptoms of choledochal cysts are caused by protein plugs made of lithostathine, which block the long common channel and increase pancreaticobiliary ductal pressure. Agents that dissolve protein plugs can provide relief from or prevent symptoms. In the present study, drugs reportedly effective for pancreatic and biliary stones were used in dissolution tests. Protein plugs were obtained from choledochal cysts during surgery in two children (5- and 6-year-old girls). Plugs approximately 2 mm in diameter were immersed in citric acid, tartaric acid, dimethadione, bromhexine, dehydrocholic acid, sodium citrate, hydrochloric acid, and sodium hydroxide solutions under observation with a digital microscope. The pH of each solution was measured using a pH meter. Plugs dissolved in citric acid (5.2 mM; pH 2.64), tartaric acid (6.7 mM; pH 2.51), dimethadione (75 mM; pH 3.70), hydrochloric acid (0.5 mM; pH 3.13), and sodium hydroxide (75 mM; pH 12.75) solutions. Plugs did not dissolve in dimethadione (7.5 mM; pH 4.31), bromhexine (0.1%; pH 4.68), dehydrocholic acid (5%; pH 7.45), and sodium citrate (75 mM; pH 7.23) solutions. Protein plugs in choledochal cysts are dissolved in acidic and basic solutions, which may eliminate longitudinal electrostatic interactions of the lithostathine protofibrils.

  4. The heterologous expression of a chrysanthemum TCP-P transcription factor CmTCP14 suppresses organ size and delays senescence in Arabidopsis thaliana.

    Science.gov (United States)

    Zhang, Ting; Qu, Yixin; Wang, Haibin; Wang, Jingjing; Song, Aiping; Hu, Yueheng; Chen, Sumei; Jiang, Jiafu; Chen, Fadi

    2017-06-01

    TCP transcription factors are important for plant growth and development, but their activity in chrysanthemum (Chrysanthemum morifolium) has not been thoroughly explored. Here, a chrysanthemum TCP-P sequence, which encodes a protein harboring the conserved basic helix-loop-helix (bHLH) motif, was shown to be related phylogenetically to the Arabidopsis thaliana gene AtTCP14. A yeast-one hybrid assay showed that the encoding protein had no transcriptional activation ability, and a localization experiment indicated that it was localized in the nucleus. Transcription profiling established that the gene was most active in the stem and leaf. Its heterologous expression in A. thaliana down-regulated certain cell cycle-related genes, reduced the size of various organs and increased the chlorophyll and carotenoid contents of the leaf which led to delayed senescence and a prolonged flowering period. Moreover, by screening the cDNA library of chrysanthemum, we found that the CmTCP14 can interact with CmFTL2 and some CmDELLAs. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  5. Proliferating neuronal progenitors in the postnatal hippocampus transiently express the proneural gene Ngn2.

    Science.gov (United States)

    Ozen, Ilknur; Galichet, Christophe; Watts, Colin; Parras, Carlos; Guillemot, François; Raineteau, Olivier

    2007-05-01

    Little is known of the transcription factors expressed by adult neural progenitors produced in the hippocampal neurogenic niche. Here, we study the expression of the proneural basic helix-loop-helix (bHLH) transcription factor Neurogenin-2 (Ngn2) in the adult hippocampus. We have characterized the pattern of expression of Ngn2 in the adult hippocampus using immunostaining for Ngn2 protein and a Ngn2-green fluorescent protein (GFP) reporter mouse strain. A significant proportion of Ngn2-expressing cells were mitotically active. Ngn2-GFP expression was restricted to the subgranular zone and declined with age. Neuronal markers were used to determine the phenotype of Ngn2-expressing cells. The vast majority of Ngn2-GFP-positive cells expressed the immature neuronal markers, doublecortin (DCX) and polysialic acid-neural cell adhesion molecule (PSA-NCAM). Finally, the pattern of Ngn2 expression was studied following seizure induction. Our data show an increase in neurogenesis, detected in these animals by bromodeoxyuridine (BrdU) and DCX staining that was contemporaneous with a marked increase in Ngn2-GFP-expression. Taken together, our results show that Ngn2-GFP represents a specific marker for neurogenesis and its modulation in the adult hippocampus. Ngn2 transient expression in proliferating neuronal progenitors supports the idea that it plays a significant role in adult neurogenesis.

  6. ABA Suppresses Root Hair Growth via the OBP4 Transcriptional Regulator1[OPEN

    Science.gov (United States)

    Kawamura, Ayako; Schäfer, Sabine; Breuer, Christian; Shibata, Michitaro; Mitsuda, Nobutaka; Ohme-Takagi, Masaru; Matsui, Minami

    2017-01-01

    Plants modify organ growth and tune morphogenesis in response to various endogenous and environmental cues. At the cellular level, organ growth is often adjusted by alterations in cell growth, but the molecular mechanisms underlying this control remain poorly understood. In this study, we identify the DNA BINDING WITH ONE FINGER (DOF)-type transcription regulator OBF BINDING PROTEIN4 (OBP4) as a repressor of cell growth. Ectopic expression of OBP4 in Arabidopsis (Arabidopsis thaliana) inhibits cell growth, resulting in severe dwarfism and the repression of genes involved in the regulation of water transport, root hair development, and stress responses. Among the basic helix-loop-helix transcription factors known to control root hair growth, OBP4 binds the ROOT HAIR DEFECTIVE6-LIKE2 (RSL2) promoter to repress its expression. The accumulation of OBP4 proteins is detected in expanding root epidermal cells, and its expression level is increased by the application of abscisic acid (ABA) at concentrations sufficient to inhibit root hair growth. ABA-dependent induction of OBP4 is associated with the reduced expression of RSL2. Furthermore, ectopic expression of OBP4 or loss of RSL2 function results in ABA-insensitive root hair growth. Taken together, our results suggest that OBP4-mediated transcriptional repression of RSL2 contributes to the ABA-dependent inhibition of root hair growth in Arabidopsis. PMID:28167701

  7. RSL class I genes positively regulate root hair development in Oryza sativa.

    Science.gov (United States)

    Kim, Chul Min; Han, Chang-Deok; Dolan, Liam

    2017-01-01

    Root hairs are filamentous protuberances from superficial cells of plant roots that are critical for nutrient uptake. Genes encoding ROOT HAIR DEFECTIVE-SIX LIKE (RSL) class I basic helix-loop-helix proteins are expressed in future root hair cells (trichoblasts) of the Arabidopsis thaliana root where they positively regulate root hair cell development. We characterized the function of class I genes in Oryza sativa root development. We show that there are three RSL class I genes in O. sativa and that each is expressed in developing root hair cells. Reduction of RSL class I function results in the development of shorter root hairs than in wild-type. Ectopic overexpression results in the development of ectopic root hair cells. These data suggest that expression of individual RSL class I proteins is sufficient for root hair development in the cereal O. sativa (rice). Therefore RSL class I genes have been conserved since O. sativa and A. thaliana last shared a common ancestor. However, given that RSL class I genes are not sufficient for root hair development in A. thaliana, it suggests that there are differences in the mechanisms repressing RSL class I gene activity between members of the Poaceae and Brassicaceae. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

  8. ¹H, ¹³C, and ¹⁵N backbone and side chain resonance assignments of the C-terminal DNA binding and dimerization domain of v-Myc.

    Science.gov (United States)

    Kızılsavaş, Gönül; Saxena, Saurabh; Żerko, Szymon; Koźmiński, Wiktor; Bister, Klaus; Konrat, Robert

    2013-10-01

    The oncogenic transcription factor Myc is one of the most interesting members of the basic-helix-loop-helix-zipper (bHLHZip) protein family. Deregulation of Myc via gene amplification, chromosomal translocation or other mechanisms lead to tumorigenesis including Burkitt lymphoma, multiple myeloma, and many other malignancies. The oncogene myc is a highly potent transforming gene and capable to transform various cell types in vivo and in vitro. Its oncogenic activity initialized by deregulated expression leads to a shift of the equilibrium in the Myc/Max/Mad network towards Myc/Max complexes. The Myc/Max heterodimerization is a prerequisite for transcriptional functionality of Myc. Primarily, we are focusing on the apo-state of the C-terminal domain of v-Myc, the retroviral homolog of human c-Myc. Based on multi-dimensional NMR measurements v-Myc appears to be neither a fully structured nor a completely unstructured protein. The bHLHZip domain of v-Myc does not exist as a random coil but exhibits partially pre-formed α-helical regions in its apo-state. In order to elucidate the structural propensities of Myc in more detail, the backbone and side-chain assignments obtained here for apo-Myc are a crucial prerequisite for further NMR measurements.

  9. TWIST is Expressed in Human Gliomas, Promotes Invasion

    Directory of Open Access Journals (Sweden)

    Maria C. Elias

    2005-09-01

    Full Text Available TWIST is a basic helix-loop-helix (bHLH transcription factor that regulates mesodermal development, promotes tumor cell metastasis, and, in response to cytotoxic stress, enhances cell survival. Our screen for bHLH gene expression in rat C6 glioma revealed TWIST. To delineate a possible oncogenic role for TWIST in the human central nervous system (CNS, we analyzed TWIST message, protein expression in gliomas, normal brain. TWIST was detected in the large majority of human glioma-derived cell lines, human gliomas examined. Increased TWIST mRNA levels were associated with the highest grade gliomas, increased TWIST expression accompanied transition from low grade to high grade in vivo, suggesting a role for TWIST in promoting malignant progression. In accord, elevated TWIST mRNA abundance preceded the spontaneous malignant transformation of cultured mouse astrocytes hemizygous for p53. Overexpression of TWIST protein in a human glioma cell line significantly enhanced tumor cell invasion, a hallmark of high-grade gliomas. These findings support roles for TWIST both in early glial tumorigenesis, subsequent malignant progression. TWIST was also expressed in embryonic, fetal human brain, in neurons, but not glia, of mature brain, indicating that, in gliomas, TWIST may promote the functions also critical for CNS development or normal neuronal physiology.

  10. An upstream open reading frame represses expression of Lc, a member of the R/B family of maize transcriptional activators

    Energy Technology Data Exchange (ETDEWEB)

    Damiani, R.D. Jr.; Wessler, S.R. (Univ. of Georgia, Athens, GA (United States))

    1993-09-01

    The R/B genes of maize encode a family of basic helix-loop-helix proteins that determine where and when the anthocyanin-pigment pathway will be expressed in the plant. Previous studies showed that allelic diversity among family members reflects differences in gene expression, specifically in transcription initiation. The authors present evidence that the R gene Lc is under translational control. They demonstrate that the 235-nt transcript leader of Lc represses expression 25- to 30-fold in an in vivo assay. Repression is mediated by the presence in cis of a 38-codon upstream open reading frame. Furthermore, the coding capacity of the upstream open reading frame influences the magnitude of repression. It is proposed that translational control does not contribute to tissue specificity but prevents overexpression of the Lc protein. The diversity of promoter and 5' untranslated leader sequences among the R/B genes provides an opportunity to study the coevolution of transcriptional and translational mechanisms of gene regulation. 36 refs., 5 figs.

  11. Longitudinal changes in C-reactive protein, proform of eosinophil major basic protein, and pregnancy-associated plasma protein-A during weight changes in obese children

    DEFF Research Database (Denmark)

    Lausten-Thomsen, Ulrik; Gamborg, Michael; Bøjsøe, Christine

    2015-01-01

    been linked to increased cardiovascular susceptibility. This study investigates these biomarkers during weight loss and regain in obese children. MATERIALS AND METHODS: A longitudinal study during a 12-week weight loss program with a 28 months follow-up was conducted. Anthropometrics and plasma......BACKGROUND: Childhood obesity is associated with several complications, including cardiovascular comorbidity. Several biomarkers, such as high-sensitive C-reactive protein (hs-CRP), proform of eosinophil major basic protein (Pro-MBP) and pregnancy associated plasma protein-A (PAPP-A), have equally......), and 2.70 (girls) were included. Ninety children completed the weight loss program and 68 children entered the follow-up program. Pro-MBP and PAPP-A, but not hs-CRP, exhibited individual-specific levels (tracking) during weight loss and regain. The PAPP-A/Pro-MBP correlation was strong, whereas the hs...

  12. Autoantibodies to myelin basic protein catalyze site-specific degradation of their antigen.

    Science.gov (United States)

    Ponomarenko, Natalia A; Durova, Oxana M; Vorobiev, Ivan I; Belogurov, Alexey A; Kurkova, Inna N; Petrenko, Alexander G; Telegin, Georgy B; Suchkov, Sergey V; Kiselev, Sergey L; Lagarkova, Maria A; Govorun, Vadim M; Serebryakova, Marina V; Avalle, Bérangère; Tornatore, Pete; Karavanov, Alexander; Morse, Herbert C; Thomas, Daniel; Friboulet, Alain; Gabibov, Alexander G

    2006-01-10

    Autoantibody-mediated tissue destruction is among the main features of organ-specific autoimmunity. This report describes "an antibody enzyme" (abzyme) contribution to the site-specific degradation of a neural antigen. We detected proteolytic activity toward myelin basic protein (MBP) in the fraction of antibodies purified from the sera of humans with multiple sclerosis (MS) and mice with induced experimental allergic encephalomyelitis. Chromatography and zymography data demonstrated that the proteolytic activity of this preparation was exclusively associated with the antibodies. No activity was found in the IgG fraction of healthy donors. The human and murine abzymes efficiently cleaved MBP but not other protein substrates tested. The sites of MBP cleavage determined by mass spectrometry were localized within immunodominant regions of MBP. The abzymes could also cleave recombinant substrates containing encephalytogenic MBP(85-101) peptide. An established MS therapeutic Copaxone appeared to be a specific abzyme inhibitor. Thus, the discovered epitope-specific antibody-mediated degradation of MBP suggests a mechanistic explanation of the slow development of neurodegeneration associated with MS.

  13. Milk basic protein increases ghrelin secretion and bone mineral density in rodents.

    Science.gov (United States)

    Ishida, Yuko; Chacrabati, Rakhi; Ono-Ohmachi, Aiko; Gong, Zhi; Ikenoya, Chika; Aizawa, Sayaka; Nara, Takayuki Y; Morita, Yoshikazu; Kato, Ken; Sakai, Takafumi; Sakata, Ichiro

    Milk basic protein (MBP), a mixture of proteins isolated from bovine milk, is known to increase bone formation. Ghrelin, a stomach-derived peptide hormone, also has been reported to stimulate osteoblast formation. The aim of this study was to determine whether MBP-induced bone formation is mediated via ghrelin. MBP was chronically administered to mice in their drinking water for 3 wk, and body weight, water intake, and bone mineral density were measured. Additionally, plasma bone-specific alkaline phosphatase, tartrate-resistant acid phosphatase isoform 5b, and ghrelin concentrations were determined by enzyme-linked immunosorbent assay. To examine the direct effect of MBP on ghrelin secretion, gastric tissue culture and primary mucosal cells were stimulated by MBP. The in vivo study of young, growing mice showed that chronic MBP intake for 3 wk increased the plasma ghrelin concentration and bone mineral density of the hind limb tibia. In vitro studies using minced rat gastric mucosa tissues and primary murine isolated gastric mucosal cells revealed that MBP stimulated ghrelin release in a dose-dependent manner. Moreover, MBP-induced ghrelin secretion was partly inhibited by adrenergic blockers. These findings suggest a novel mechanism by which MBP directly acts on ghrelin secretion. Additionally, the elevated ghrelin level induced by MBP may act as a mediator for bone formation. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Charge isomers of myelin basic protein: structure and interactions with membranes, nucleotide analogues, and calmodulin.

    Directory of Open Access Journals (Sweden)

    Chaozhan Wang

    Full Text Available As an essential structural protein required for tight compaction of the central nervous system myelin sheath, myelin basic protein (MBP is one of the candidate autoantigens of the human inflammatory demyelinating disease multiple sclerosis, which is characterized by the active degradation of the myelin sheath. In this work, recombinant murine analogues of the natural C1 and C8 charge components (rmC1 and rmC8, two isoforms of the classic 18.5-kDa MBP, were used as model proteins to get insights into the structure and function of the charge isomers. Various biochemical and biophysical methods such as size exclusion chromatography, calorimetry, surface plasmon resonance, small angle X-ray and neutron scattering, Raman and fluorescence spectroscopy, and conventional as well as synchrotron radiation circular dichroism were used to investigate differences between these two isoforms, both from the structural point of view, and regarding interactions with ligands, including calmodulin (CaM, various detergents, nucleotide analogues, and lipids. Overall, our results provide further proof that rmC8 is deficient both in structure and especially in function, when compared to rmC1. While the CaM binding properties of the two forms are very similar, their interactions with membrane mimics are different. CaM can be used to remove MBP from immobilized lipid monolayers made of synthetic lipids--a phenomenon, which may be of relevance for MBP function and its regulation. Furthermore, using fluorescently labelled nucleotides, we observed binding of ATP and GTP, but not AMP, by MBP; the binding of nucleoside triphosphates was inhibited by the presence of CaM. Together, our results provide important further data on the interactions between MBP and its ligands, and on the differences in the structure and function between MBP charge isomers.

  15. Analysis of the induction of the myelin basic protein binding to the plasma membrane phospholipid monolayer

    International Nuclear Information System (INIS)

    Zhang Lei; Hao Changchun; Feng Ying; Gao Feng; Lu Xiaolong; Li Junhua; Sun Runguang

    2016-01-01

    Myelin basic protein (MBP) is an essential structure involved in the generation of central nervous system (CNS) myelin. Myelin shape has been described as liquid crystal structure of biological membrane. The interactions of MBP with monolayers of different lipid compositions are responsible for the multi-lamellar structure and stability of myelin. In this paper, we have designed MBP-incorporated model lipid monolayers and studied the phase behavior of MBP adsorbed on the plasma membrane at the air/water interface by thermodynamic method and atomic force microscopy (AFM). By analyzing the pressure–area ( π – A ) and pressure–time ( π – T ) isotherms, univariate linear regression equation was obtained. In addition, the elastic modulus, surface pressure increase, maximal insertion pressure, and synergy factor of monolayers were detected. These parameters can be used to modulate the monolayers binding of protein, and the results show that MBP has the strongest affinity for 1,2-dipalmitoyl-sn-glycero-3- phosphoserine (DPPS) monolayer, followed by DPPC/DPPS mixed and 1,2-dipalmitoyl-sn-glycero-3-phospho-choline (DPPC) monolayers via electrostatic and hydrophobic interactions. AFM images of DPPS and DPPC/DPPS mixed monolayers in the presence of MBP (5 nM) show a phase separation texture at the surface pressure of 20 mN/m and the incorporation of MBP put into the DPPC monolayers has exerted a significant effect on the domain structure. MBP is not an integral membrane protein but, due to its positive charge, interacts with the lipid head groups and stabilizes the membranes. The interaction between MBP and phospholipid membrane to determine the nervous system of the disease has a good biophysical significance and medical value. (special topic)

  16. Ha-Ras transformation of MCF10A cells leads to repression of Singleminded-2s through NOTCH and C/EBPbeta.

    Science.gov (United States)

    Gustafson, T L; Wellberg, E; Laffin, B; Schilling, L; Metz, R P; Zahnow, C A; Porter, W W

    2009-03-26

    We have previously shown that Singleminded-2s (SIM2s), a member of the basic helix-loop-helix Per-Arnt-Sim (bHLH/PAS) family of transcription factors, is downregulated in breast cancer samples and has tumor suppressor activity. However, the mechanism by which SIM2s is repressed in breast cancer cells has not been determined. In this study, we show that transformation of MCF10A cells by Harvey-Ras (Ha-Ras) induces CCAAT/enhance binding protein beta (C/EBPbeta) and activates the NOTCH signaling pathway to block SIM2s gene expression. NOTCH-mediated repression acts through a C-repeat binding factor 1 (CBF1)-independent mechanism, as introduction of CBF1 had no effect on SIM2s expression. Consistent with C/ebpbeta-dependent inhibition of SIM2s, C/ebpbeta(-/-) mouse mammary glands express high levels of SIM2s and reestablishment of C/ebpbeta isoforms decreased SIM2s mRNA levels in C/ebpbeta immortalized mammary epithelial cell lines. These studies illustrate a novel pathway of tumor suppressor gene silencing in Ha-Ras-transformed breast epithelial cells and identify SIM2s as a target of C/EBPbeta and NOTCH signaling.

  17. Virulence Factors of Geminivirus Interact with MYC2 to Subvert Plant Resistance and Promote Vector Performance[C][W

    Science.gov (United States)

    Li, Ran; Weldegergis, Berhane T.; Li, Jie; Jung, Choonkyun; Qu, Jing; Sun, Yanwei; Qian, Hongmei; Tee, ChuanSia; van Loon, Joop J.A.; Dicke, Marcel; Chua, Nam-Hai; Liu, Shu-Sheng

    2014-01-01

    A pathogen may cause infected plants to promote the performance of its transmitting vector, which accelerates the spread of the pathogen. This positive effect of a pathogen on its vector via their shared host plant is termed indirect mutualism. For example, terpene biosynthesis is suppressed in begomovirus-infected plants, leading to reduced plant resistance and enhanced performance of the whiteflies (Bemisia tabaci) that transmit these viruses. Although begomovirus-whitefly mutualism has been known, the underlying mechanism is still elusive. Here, we identified βC1 of Tomato yellow leaf curl China virus, a monopartite begomovirus, as the viral genetic factor that suppresses plant terpene biosynthesis. βC1 directly interacts with the basic helix-loop-helix transcription factor MYC2 to compromise the activation of MYC2-regulated terpene synthase genes, thereby reducing whitefly resistance. MYC2 associates with the bipartite begomoviral protein BV1, suggesting that MYC2 is an evolutionarily conserved target of begomoviruses for the suppression of terpene-based resistance and the promotion of vector performance. Our findings describe how this viral pathogen regulates host plant metabolism to establish mutualism with its insect vector. PMID:25490915

  18. Disease-related growth factor and embryonic signaling pathways modulate an enhancer of TCF21 expression at the 6q23.2 coronary heart disease locus.

    Directory of Open Access Journals (Sweden)

    Clint L Miller

    Full Text Available Coronary heart disease (CHD is the leading cause of mortality in both developed and developing countries worldwide. Genome-wide association studies (GWAS have now identified 46 independent susceptibility loci for CHD, however, the biological and disease-relevant mechanisms for these associations remain elusive. The large-scale meta-analysis of GWAS recently identified in Caucasians a CHD-associated locus at chromosome 6q23.2, a region containing the transcription factor TCF21 gene. TCF21 (Capsulin/Pod1/Epicardin is a member of the basic-helix-loop-helix (bHLH transcription factor family, and regulates cell fate decisions and differentiation in the developing coronary vasculature. Herein, we characterize a cis-regulatory mechanism by which the lead polymorphism rs12190287 disrupts an atypical activator protein 1 (AP-1 element, as demonstrated by allele-specific transcriptional regulation, transcription factor binding, and chromatin organization, leading to altered TCF21 expression. Further, this element is shown to mediate signaling through platelet-derived growth factor receptor beta (PDGFR-β and Wilms tumor 1 (WT1 pathways. A second disease allele identified in East Asians also appears to disrupt an AP-1-like element. Thus, both disease-related growth factor and embryonic signaling pathways may regulate CHD risk through two independent alleles at TCF21.

  19. Signaling pathways and late-onset gene induction associated with renal mesangial cell hypertrophy.

    Science.gov (United States)

    Goruppi, Sandro; Bonventre, Joseph V; Kyriakis, John M

    2002-10-15

    In chronic diseases such as diabetes mellitus, continuous stress stimuli trigger a persistent, self-reinforcing reprogramming of cellular function and gene expression that culminates in the pathological state. Late-onset, stable changes in gene expression hold the key to understanding the molecular basis of chronic diseases. Renal failure is a common, but poorly understood complication of diabetes. Diabetic nephropathy begins with mesangial cell hypertrophy and hyperplasia, combined with excess matrix deposition. The vasoactive peptide endothelin promotes the mesangial cell hypertophy characteristic of diabetic nephropathy. In this study, we examined the signaling pathways and changes in gene expression required for endothelin-induced mesangial cell hypertrophy. Transcriptional profiling identified seven genes induced with slow kinetics by endothelin. Of these, p8, which encodes a small basic helix-loop-helix protein, was most strongly and stably induced. p8 is also induced in diabetic kidney. Mesangial cell hypertrophy and p8 induction both require activation of the ERK, JNK/SAPK and PI-3-K pathways. Small interfering RNA (siRNA)-mediated RNA interference indicates that p8 is required for endothelin-induced hypertrophy. Thus, p8 is a novel marker for diabetic renal hypertrophy.

  20. Two R2R3-MYB genes, homologs of Petunia AN2, regulate anthocyanin biosyntheses in flower Tepals, tepal spots and leaves of asiatic hybrid lily.

    Science.gov (United States)

    Yamagishi, Masumi; Shimoyamada, Yoshihiro; Nakatsuka, Takashi; Masuda, Kiyoshi

    2010-03-01

    Anthocyanins are secondary metabolites that contribute to colors of flowers, fruits and leaves. Asiatic hybrid lily (Lilium spp.) accumulates cyanidin anthocyanins in flower tepals, tepal spots and leaves of juvenile shoots. To clarify their mechanisms of regulation of anthocyanin pigmentation, two full-length cDNAs of R2R3-MYB (LhMYB6 and LhMYB12) were isolated from the anthocyanin-accumulating tepals of cultivar 'Montreux'. Analysis of the deduced amino acid sequences indicated they have homology with petunia AN2, homologous sequences of which had not been isolated in species of monocots. Yeast two-hybrid analysis showed that LhMYB6 and LhMYB12 interacted with the Lilium hybrid basic helix-loop-helix 2 (LhbHLH2) protein. Transient expression analysis indicated that co-expression of LhMYB6 and LhbHLH2 or LhMYB12 and LhbHLH2, introduced by a microprojectile, activated the transcription of anthocyanin biosynthesis genes in lily bulbscales. Spatial and temporal transcription of LhMYB6 and LhMYB12 was analyzed. The expression of LhMYB12 corresponded well with anthocyanin pigmentation in tepals, filaments and styles, and that of LhMYB6 correlated with anthocyanin spots in tepals and light-induced pigmentation in leaves. These results indicate that LhMYB6 and LhMYB12 positively regulate anthocyanin biosynthesis and determine organ- and tissue-specific accumulation of anthocyanin.

  1. The effect of carbon monoxide integrating nitric oxide through auxin signal in Arabidopsis to modulate iron deficiency

    Directory of Open Access Journals (Sweden)

    Liming eYang

    2016-03-01

    Full Text Available Carbon monoxide (CO and nitric oxide (NO are essential modulators that regulate the plant response to iron deficiency (-Fe. Auxin is a phytohormone that plays important roles in plant growth and development. We report here that in Arabidopsis –Fe enhanced heme oxygenase-dependent CO generation and auxin transport through redistribution of PIN1 protein, which subsequently increased NO accumulation; NO signaling regulated the activity of ferric chelate reductase (FCR and the expression of Fe-uptake genes including basic helix-loop-helix transcription factor (FIT and the ferric reduction oxidase 2 (FRO2. Over-expression of HY1 encoding heme oxygenase, or treatment with CO donor enhanced basipetal auxin transport, FCR activity, and the expressions of FIT and FRO2 under –Fe. Such effects were compromised in the mutant aux1-7 impaired in auxin transport or in the mutant noa1 or nia1/nia2 defective in NO biosynthesis. -Fe failed to promote auxin transport and FCR activity in hy1 mutant; such inability was reversed in the double mutant of hy1/yucca1 with elevated auxin production, or in hy1/cue1 mutant with NO over-accumulation. Taken together, our results suggest that CO modulates NO signaling through auxin to cope with Fe deficiency in Arabidopsis.

  2. The mutational spectrum in Waardenburg syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Read, A.P.; Tassabehji, M.; Liu, X.Z. [and others

    1994-09-01

    101 individuals or families with Waardenburg syndrome (WS) or related abnormalities have been screened for mutations in the PAX3 gene. PAX3 mutations were seen in 19 of 35 individuals or families with features of Type I Waardenburg syndrome. None of the 47 Type 2 WS families showed any PAX3 mutation, nor did any of 19 individuals with other neural crest syndromes or pigmentary disturbances. PAX3 mutations included substitutions of highly conserved amino acids, splice site mutations, nonsense mutations and frameshifting deletions or insertions. One patient (with Type 1 WS, mental retardation and growth retardation) had a chromosomal deletion of 7-8 Mb encompassing the PAX3 gene. Mutations were seen in each of exons 2-6, with a concentration in the 5{prime} part of the paired box (exon 2) and the 3{prime} part of the homeobox (exon 6). There was no evident relation between the molecular change and the clinical manifestations in mutation carriers. We conclude that PAX3 dosage effects very specifically produce dystopia canthorum, the distinguishing feature of Type 1 WS, and variably produce the other features of Type 1 WS depending on genetic background or chance events. Two of the Type 2 families showed linkage to markers from 3p14, the location of the MITF gene. MITF encodes a basic helix-loop-helix-zipper protein which is the homologue of the mouse microphthalmia gene product. It is likely that mutations in MITF cause some but not all Type 2 WS.

  3. Tfe3 expression is closely associated to macrophage terminal differentiation of human hematopoietic myeloid precursors

    International Nuclear Information System (INIS)

    Zanocco-Marani, Tommaso; Vignudelli, Tatiana; Gemelli, Claudia; Pirondi, Sara; Testa, Anna; Montanari, Monica; Parenti, Sandra; Tenedini, Elena; Grande, Alexis; Ferrari, Sergio

    2006-01-01

    The MItf-Tfe family of basic helix-loop-helix leucine zipper (bHLH-Zip) transcription factors encodes four family members: MItf, Tfe3, TfeB and TfeC. In vitro, each protein of the family binds DNA in a homo- or heterodimeric form with other family members. Tfe3 is involved in chromosomal translocations recurrent in different tumors and it has been demonstrated, by in vivo studies, that it plays, redundantly with MItf, an important role in the process of osteoclast formation, in particular during the transition from mono-nucleated to multi-nucleated osteoclasts. Since mono-nucleated osteoclasts derive from macrophages we investigated whether Tfe3 might play a role upstream during hematopoietic differentiation. Here we show that Tfe3 is able to induce mono-macrophagic differentiation of U937 cells, in association with a decrease of cell proliferation and an increase of apoptosis. We also show that Tfe3 does not act physiologically during commitment of CD34+ hematopoietic stem cells (HSCs), since it is not able to direct HSCs toward a specific lineage as observed by clonogenic assay, but is a strong actor of terminal differentiation since it allows human primary myeloblasts' maturation toward the macrophage lineage

  4. Myelin basic protein determination in cerebro-spinal fluid of children with tuberculous meningitis

    International Nuclear Information System (INIS)

    Samuel, A.M.; Dhalla, A.S.; Mazarello, T.

    1986-01-01

    Myelin basic protein (MBP), an indicator of neural tissue damage in cerebro-spinal fluid, was studied in patients with tuberculous meningitis (TBM). MBP levels were elevated in 62% of the cases of TBM, the levels being 13.3+-18.8 ng/mL, compared with control levels of 1.34+-0.55 ng/mL(p<0.001). MBP level was related to certain clinical features of the disease, such as level of consciousness, neurological characteristics associated with signs of raised intracranial tension and the presence of arteritis associated with hydrocephalus. However, its greatest significance was its correlation with the progress of disease. Persistence of high levels of MBP over a period of a few weeks was associated with little or no improvement in the clinical state of the patient or a higher mortality rate. Return to normal levels of MBP indicated a more favourable outcome of disease. Hence MBP estimation gave not only an indicator of the degree of neurological damage but also an important marker to evaluate patients' progress and response to treatment. (author)

  5. PCR typing of two short tandem repeat (STR) structures upstreams of the human myelin basic protein (MBP) gene

    DEFF Research Database (Denmark)

    Nellemann, L J; Frederiksen, J; Morling, N

    1995-01-01

    We investigated two short tandem tetranucleotide (TGGA) repeat polymorphisms upstreams of the myelin basic protein (MBP) gene. The region was amplified by the polymerase chain reaction (PCR) and the two repeat systems were separated by cutting with the restriction enzyme NlaIII. The lengths...

  6. Variation in NOD2 augments Th2- and Th17 responses to myelin basic protein in multiple sclerosis

    DEFF Research Database (Denmark)

    Hedegaard, Chris Juul; Enevold, Christian; Sellebjerg, Finn

    2011-01-01

    cell proliferation elicited by human myelin basic protein (MBP) in blood mononuclear cell (MNC) cultures from 29 patients with MS. No polymorphism was observed at rs5743277. No associations with the rs2066842 polymorphism were found. Concerning rs5743291, none were homozygous for the minor allele...

  7. Uptake and presentation of myelin basic protein by normal human B cells.

    Directory of Open Access Journals (Sweden)

    Marie Klinge Brimnes

    Full Text Available B cells may play both pathogenic and protective roles in T-cell mediated autoimmune diseases such as multiple sclerosis (MS. These functions relate to the ability of B cells to bind and present antigens. Under serum-free conditions we observed that 3-4% of circulating B cells from healthy donors were capable of binding the MS-associated self-antigen myelin basic protein (MBP and of presenting the immunodominant peptide MBP85-99, as determined by staining with the mAb MK16 recognising the peptide presented by HLA-DR15-positive cells. In the presence of serum, however, the majority of B cells bound MBP in a complement-dependent manner, and almost half of the B cells became engaged in presentation of MBP85-99. Even though complement receptor 1 (CR1, CD35 and CR2 (CD21 both contributed to binding of MBP to B cells, only CR2 was important for the subsequent presentation of MBP85-99. A high proportion of MBP85-99 presenting B cells expressed CD27, and showed increased expression of CD86 compared to non-presenting B cells. MBP-pulsed B cells induced a low frequency of IL-10-producing CD4+ T cells in 3 out of 6 donors, indicating an immunoregulatory role of B cells presenting MBP-derived peptides. The mechanisms described here refute the general assumption that B-cell presentation of self-antigens requires uptake via specific B-cell receptors, and may be important for maintenance of tolerance as well as for driving T-cell responses in autoimmune diseases.

  8. Basic Concepts in G-Protein-Coupled Receptor Homo- and Heterodimerization

    Directory of Open Access Journals (Sweden)

    Rafael Franco

    2007-01-01

    Full Text Available Until recently, heptahelical G-protein-coupled receptors (GPCRs were considered to be expressed as monomers on the cell surface of neuronal and non-neuronal cells. It is now becoming evident that this view must be overtly changed since these receptors can form homodimers, heterodimers, and higher-order oligomers on the plasma membrane. Here we discuss some of the basics and some new concepts of receptor homo- and heteromerization. Dimers-oligomers modify pharmacology, trafficking, and signaling of receptors. First of all, GPCR dimers must be considered as the main molecules that are targeted by neurotransmitters or by drugs. Thus, binding data must be fitted to dimer-based models. In these models, it is considered that the conformational changes transmitted within the dimer molecule lead to cooperativity. Cooperativity must be taken into account in the binding of agonists-antagonists-drugs and also in the binding of the so-called allosteric modulators. Cooperativity results from the intramolecular cross-talk in the homodimer. As an intramolecular cross-talk in the heterodimer, the binding of one neurotransmitter to one receptor often affects the binding of the second neurotransmitter to the partner receptor. Coactivation of the two receptors in a heterodimer can change completely the signaling pathway triggered by the neurotransmitter as well as the trafficking of the receptors. Heterodimer-specific drugs or dual drugs able to activate the two receptors in the heterodimer simultaneously emerge as novel and promising drugs for a variety of central nervous system (CNS therapeutic applications.

  9. IgG reactivity against citrullinated myelin basic protein in multiple sclerosis.

    Science.gov (United States)

    de Seze, J; Dubucquoi, S; Lefranc, D; Virecoulon, F; Nuez, I; Dutoit, V; Vermersch, P; Prin, L

    2001-07-02

    An increased level of citrullinated myelin basic protein (MBP-C8) has been reported in the brains of multiple sclerosis (MS) patients. However, the involvement of the immune response to post-translational modified MBP in the pathophysiology of MS remains speculative. The aim of this study was to compare the levels of immunoglobulin G antibodies to several MBP epitopes, before and after citrullination, in the cerebrospinal fluid (CSF) and sera of MS patients using enzyme-linked immunosorbent assay (ELISA). We analyzed antibody reactivity against various MBP-peptides in the CSF and sera of 60 MS patients, and 30 patients with other neurological diseases (OND) as controls. The peptides tested were: MBP(75-98) (peptide 1), native (peptide 2) and citrullinated (peptide 3) MBP(108-126) (ARG(122)-->Cit(122)), and native (peptide 4) and citrullinated (peptide 5) MBP(151-170) (ARG(159, 170)-->Cit(159, 170)). All selected peptides could support an immune reactivity in CSF and sera of MS and OND patients. A higher reactivity against peptide 4 was found in the CSF of MS patients compared with OND patients (P<0.0001), but not against citrullinated peptides (peptides 3 and 5). However, we observed that the citrullination state of peptide 2 modified the patterns of immune reactivity more markedly in MS patients (P<0.0001) than in OND patients (P<0.02). Although some MBP epitopes could be a potential target in MS, our data did not demonstrate any difference of antibody response to MBP peptides in their citrullinated forms.

  10. The HLA-DP2 protein binds the immunodominant epitope from myelin basic protein, MBP85-99, with high affinity

    DEFF Research Database (Denmark)

    Hansen, B E; Nielsen, Claus Henrik; Madsen, H O

    2011-01-01

    Myelin basic protein (MBP) is a candidate autoantigen in multiple sclerosis (MS). The immunodominant epitope for T-cell responses is assigned to the amino acid sequence MBP84-102, which binds to human leukocyte antigen (HLA)-DR2a (DRB5*0101) and HLA-DR2b (DRB1*1501) of the HLA-DR2 haplotype...

  11. Focal cerebral ischemia induces increased myelin basic protein and growth-associated protein-43 gene transcription in peri-infarct areas in the rat brain

    DEFF Research Database (Denmark)

    Gregersen, R; Christensen, Thomas; Lehrmann, E

    2001-01-01

    Although oligodendrocytes are vulnerable to focal cerebral ischemia, remyelination of denuded or regenerating axons in the peri-infarct area has been observed in the central nervous system. We studied the expression of myelin basic protein (MBP), a major component of central nervous system myelin...

  12. LIN-32/Atonal Controls Oxygen Sensing Neuron Development in Caenorhabditis elegans

    DEFF Research Database (Denmark)

    Romanos, Teresa Rojo; Pladevall-Morera, David; Langebeck-Jensen, Kasper

    2017-01-01

    Development of complex nervous systems requires precisely controlled neurogenesis. The generation and specification of neurons occur through the transcriptional and post-Transcriptional control of complex regulatory networks. In vertebrates and invertebrates, the proneural basic-helix-loop-helix (b......HLH) family of transcription factors has multiple functions in neurogenesis. Here, we identified the LIN-32/Atonal bHLH transcription factor as a key regulator of URXL/R oxygen-sensing neuron development in Caenorhabditis elegans. When LIN-32/Atonal expression is lost, the expression of URX specification...

  13. Origins and evolution of stomatal development

    OpenAIRE

    Chater, C.; Caine, R.S.; Fleming, A.J.; Gray, J.E.

    2017-01-01

    The fossil record suggests stomata-like pores were present on the surfaces of land plants over 400 million years ago.\\ud Whether stomata arose once or whether they arose independently across newly evolving land plant lineages has long been\\ud a matter of debate. In Arabidopsis, a genetic toolbox has been identified that tightly controls stomatal development and\\ud patterning. This includes the basic helix-loop-helix (bHLH) transcription factors SPEECHLESS (SPCH), MUTE, FAMA, and\\ud ICE/SCREAM...

  14. Transcriptional regulatory networks downstream of TAL1/SCL in T-cell acute lymphoblastic leukemia

    OpenAIRE

    Palomero, Teresa; Odom, Duncan T.; O'Neil, Jennifer; Ferrando, Adolfo A.; Margolin, Adam; Neuberg, Donna S.; Winter, Stuart S.; Larson, Richard S.; Li, Wei; Liu, X. Shirley; Young, Richard A.; Look, A. Thomas

    2006-01-01

    Aberrant expression of 1 or more transcription factor oncogenes is a critical component of the molecular pathogenesis of human T-cell acute lymphoblastic leukemia (T-ALL); however, oncogenic transcriptional programs downstream of T-ALL oncogenes are mostly unknown. TAL1/SCL is a basic helix-loop-helix (bHLH) transcription factor oncogene aberrantly expressed in 60% of human T-ALLs. We used chromatin immunoprecipitation (ChIP) on chip to identify 71 direct transcriptional targets of TAL1/SCL. ...

  15. Calcium receptor expression and function in oligodendrocyte commitment and lineage progression: potential impact on reduced myelin basic protein in CaR-null mice

    DEFF Research Database (Denmark)

    Chattopadhyay, N.; Espinosa-Jeffrey, A.; Yano, S.

    2008-01-01

    cellular proliferation. We further observed that high Ca(2+) stimulates the mRNA levels of myelin basic protein in preoligodendrocytes, which is also CaR mediated. Finally, myelin basic protein levels were significantly reduced in the cerebellum of CaR-null mice during development. Our results show that Ca...

  16. Translation of myelin basic protein mRNA in oligodendrocytes is regulated by integrin activation and hnRNP-K

    DEFF Research Database (Denmark)

    Laursen, Lisbeth Schmidt; Chan, Colin W; ffrench-Constant, Charles

    2011-01-01

    Myelination in the central nervous system provides a unique example of how cells establish asymmetry. The myelinating cell, the oligodendrocyte, extends processes to and wraps multiple axons of different diameter, keeping the number of wraps proportional to the axon diameter. Local regulation...... of protein synthesis represents one mechanism used to control the different requirements for myelin sheath at each axo–glia interaction. Prior work has established that β1-integrins are involved in the axoglial interactions that initiate myelination. Here, we show that integrin activation regulates...... translation of a key sheath protein, myelin basic protein (MBP), by reversing the inhibitory effect of the mRNA 3′UTR. During oligodendrocyte differentiation and myelination α6β1-integrin interacts with hnRNP-K, an mRNA-binding protein, which binds to MBP mRNA and translocates from the nucleus to the myelin...

  17. Vaccination with DNA Encoding an Immunodominant Myelin Basic Protein Peptide Targeted to Fc of Immunoglobulin G Suppresses Experimental Autoimmune Encephalomyelitis

    OpenAIRE

    Lobell, Anna; Weissert, Robert; Storch, Maria K.; Svanholm, Cecilia; de Graaf, Katrien L.; Lassmann, Hans; Andersson, Roland; Olsson, Tomas; Wigzell, Hans

    1998-01-01

    We explore here if vaccination with DNA encoding an autoantigenic peptide can suppress autoimmune disease. For this purpose we used experimental autoimmune encephalomyelitis (EAE), which is an autoaggressive disease in the central nervous system and an animal model for multiple sclerosis. Lewis rats were vaccinated with DNA encoding an encephalitogenic T cell epitope, guinea pig myelin basic protein peptide 68–85 (MBP68–85), before induction of EAE with MBP68–85 in complete Freund's adjuvant....

  18. Degradation of structurally characterized proteins injected into HeLa cells. Basic measurements

    International Nuclear Information System (INIS)

    Rogers, S.W.; Rechsteiner, M.

    1988-01-01

    Thirty-five proteins of known x-ray structure were labeled by chloramine-T radioiodination or by reaction with 125I-Bolton-Hunter reagent and introduced into HeLa cells using red cell-mediated microinjection. Degradation rates of the injected proteins were then determined over the next 50 h by measuring the release of soluble isotope to the culture medium. Control experiments demonstrated that the measured rates were not compromised by proteolysis within RBCs, the presence of unfused RBCs, or degradation of protein released from RBCs to the medium. Degradation of some injected proteins was faster during the first 12 h after fusion than at later times, apparently a response of HeLa cells to trypsinization. However, all proteins exhibited first-order degradation rates between 24 and 48 h post injection. Except for seven proteins, stabilities measured during this interval were unaffected by the labeling procedure. Reductive methylation was used to choose among the seven discordant values, and half-lives for the 35 proteins ranged from 16 h for lysozyme to 214 h for yeast alcohol dehydrogenase. Since half-lives for six of the injected proteins closely match values obtained by in vivo measurements, we consider our estimates of the metabolic stabilities of the injected proteins to be generally accurate. Therefore, the half-lives obtained by microinjection should prove useful in the search for relationships between protein structure and intracellular stability

  19. Maid (GCIP) is involved in cell cycle control of hepatocytes

    DEFF Research Database (Denmark)

    Sonnenberg-Riethmacher, Eva; Wüstefeld, Torsten; Miehe, Michaela

    2007-01-01

    . Therefore, we studied the role of Maid during cell cycle progression after partial hepatectomy (PH). Lack of Maid expression after PH was associated with a delay in G1/S-phase progression as evidenced by delayed cyclinA expression and DNA replication in Maid-deficient mice. However, at later time points......The function of Maid (GCIP), a cyclinD-binding helix-loop-helix protein, was analyzed by targeted disruption in mice. We show that Maid function is not required for normal embryonic development. However, older Maid-deficient mice-in contrast to wild-type controls--develop hepatocellular carcinomas...

  20. Myf-6, a new member of the human gene family of myogenic determination factors: evidence for a gene cluster on chromosome 12.

    OpenAIRE

    Braun, T; Bober, E; Winter, B; Rosenthal, N; Arnold, H H

    1990-01-01

    The Myf-6 gene, a novel member of the human gene family of muscle determination factors has been detected by its highly conserved sequence coding for a putative helix-loop-helix domain. This sequence motif is a common feature of all Myf factors and other regulatory proteins. The new Myf gene is located on human chromosome 12, approximately 6.5 Kb upstream of the Myf-5 locus in a closely linked cluster of myogenic determination genes. Myf-6 cDNAs were isolated from human and mouse skeletal mus...

  1. The Impact of "Coat Protein-Mediated Virus Resistance" in Applied Plant Pathology and Basic Research.

    Science.gov (United States)

    Lindbo, John A; Falk, Bryce W

    2017-06-01

    Worldwide, plant viruses cause serious reductions in marketable crop yield and in some cases even plant death. In most cases, the most effective way to control virus diseases is through genetically controlled resistance. However, developing virus-resistant (VR) crops through traditional breeding can take many years, and in some cases is not even possible. Because of this, the demonstration of the first VR transgenic plants in 1985 generated much attention. This seminal report served as an inflection point for research in both basic and applied plant pathology, the results of which have dramatically changed both basic research and in a few cases, commercial crop production. The typical review article on this topic has focused on only basic or only applied research results stemming from this seminal discovery. This can make it difficult for the reader to appreciate the full impact of research on transgenic virus resistance, and the contributions from fundamental research that led to translational applications of this technology. In this review, we take a global view of this topic highlighting the significant changes to both basic and applied plant pathology research and commercial food production that have accumulated in the last 30 plus years. We present these milestones in the historical context of some of the scientific, economic, and environmental drivers for developing specific VR crops. The intent of this review is to provide a single document that adequately records the significant accomplishments of researchers in both basic and applied plant pathology research on this topic and how they relate to each other. We hope this review therefore serves as both an instructional tool for students new to the topic, as well as a source of conversation and discussion for how the technology of engineered virus resistance could be applied in the future.

  2. Experimental allergic encephalomyelitis in the Lewis rat: farther delineation of active sites in guinea pig and bovine myelin basic proteins.

    Science.gov (United States)

    Martenson, R E; Nomura, K; Levine, S; Sowinski, R

    1977-04-01

    Highly encephalitogenic peptide (37-88), derived from the guinea pig myelin basic protein by peptic digestion, was treated chemically to destroy its tyrosyl and histidyl residues and enzymatically to remove its C-terminal sequence Val-His-Phe. Neither of the modifications resulted in loss of activity in Lewis rats. The enccephalitogenic region within peptide (37-88) was located by examination of derivative peptides obtained by selective proteolytic cleavage. The results showed that peptide (61-88), like peptide (43-88), was fully active at the level of 0.02 nmole whereas peptides (72-88) and (72-84) were fully active at levels of 0.5 and 2.5 nmole, respectively. In contrast, peptides (43-71) and (75-88) were completely inactive. These results demonstrated that the undecapeptide Gln-Lys-Ser-Gln-Arg-Ser-Gln-Asp-Glu-Asn-Pro (residues 72-84), although not as encephalitogenic as peptides (43-88) or (61-88), does contain the elements essential for the induction of disease. At the levels tested (10.8 and 2.2 nmole) only peptides (43-88) and (61-88) were capable of inhibiting the induciton of disease by passively transferred lymph node cells; this inhibition, however, was less than that achieved by the intact guinea pig basic protein. Further studies on the encephalitogenicity of the bovine basic protein in Lewis rats demonstrated that the active site in the C-terminal half of this protein is present in its entirety within residues 89 to 115.

  3. Vipp1 is required for basic thylakoid membrane formation but not for the assembly of thylakoid protein complexes.

    Science.gov (United States)

    Aseeva, Elena; Ossenbühl, Friederich; Sippel, Claudia; Cho, Won K; Stein, Bernhard; Eichacker, Lutz A; Meurer, Jörg; Wanner, Gerhard; Westhoff, Peter; Soll, Jürgen; Vothknecht, Ute C

    2007-02-01

    Vipp1 (vesicle inducing protein in plastids 1) is found in cyanobacteria and chloroplasts where it is essential for thylakoid formation. Arabidopsis thaliana mutant plants with a reduction of Vipp1 to about 20% of wild type content become albinotic at an early stage. We propose that this drastic phenotype results from an inability of the remaining Vipp1 protein to assemble into a homo-oligomeric complex, indicating that oligomerization is a prerequisite for Vipp1 function. A Vipp1-ProteinA fusion protein, expressed in the Deltavipp1 mutant background, is able to reinstate oligomerization and restore photoautotrophic growth. Plants containing Vipp1-ProteinA in amounts comparable to Vipp1 in the wild type exhibit a wild type phenotype. However, plants with a reduced amount of Vipp1-ProteinA protein are growth-retarded and significantly paler than the wild type. This phenotype is caused by a decrease in thylakoid membrane content and a concomitant reduction in photosynthetic activity. To the extent that thylakoid membranes are made in these plants they are properly assembled with protein-pigment complexes and are photosynthetically active. This strongly supports a function of Vipp1 in basic thylakoid membrane formation and not in the functional assembly of thylakoid protein complexes. Intriguingly, electron microscopic analysis shows that chloroplasts in the mutant plants are not equally affected by the Vipp1 shortage. Indeed, a wide range of different stages of thylakoid development ranging from wild-type-like chloroplasts to plastids nearly devoid of thylakoids can be observed in organelles of one and the same cell.

  4. Nucleocapsid protein VP15 is the basic DNA binding protein of white spot syndrome virus of shrimp

    NARCIS (Netherlands)

    Witteveldt, J.; Vermeesch, A.M.G.; Langenhof, M.; Lang, de A.; Vlak, J.M.; Hulten, van M.C.W.

    2005-01-01

    White spot syndrome virus (WSSV) is type species of the genus Whispovirus of the new family Nimaviridae. Despite the elucidation of its genomic sequence, very little is known about the virus as only 6% of its ORFs show homology to known genes. One of the structural virion proteins, VP15, is part of

  5. Cyclooxygenase-2 and hypoxia-regulated proteins are modulated by basic fibroblast growth factor in acute renal failure

    Directory of Open Access Journals (Sweden)

    Sandra Villanueva

    2012-01-01

    Full Text Available Acute renal failure (ARF can be caused by injuries that induce tissue hypoxia, which in turn can trigger adaptive or inflammatory responses. We previously showed the participation of basic fibroblast growth factor (FGF-2 in renal repair. Based on this, the aim of this study was to analyze the effect of FGF-2 signaling pathway manipulation at hypoxia-induced protein levels, as well as in key proteins from the vasoactive systems of the kidney. We injected rat kidneys with FGF-2 recombinant protein (r-FGF or FGF-2 receptor antisense oligonucleotide (FGFR2-ASO after bilateral ischemia, and evaluated the presence of iNOS, EPO and HO-1, in representation of hypoxia-induced proteins, as well as COX-2, renin, kallikrein, and B2KR, in representation of the vasoactive systems of the kidney. A reduction in iNOS, HO-1, EPO, renin, kallikrein, B2KR, and in renal damage was observed in animals treated with r-FGF. The opposite effect was found with FGF-2 receptor down-regulation. In contrast, COX-2 protein levels were higher in kidneys treated with r-FGF and lower in those that received FGFR2-ASO, as compared to saline treated kidneys. These results suggest that the protective role of FGF-2 in the pathogenesis of ARF induced by I/R is a complex process, through which a differential regulation of metabolic pathways takes place.

  6. Interaction between the C-terminal region of human myelin basic protein and calmodulin: analysis of complex formation and solution structure

    Directory of Open Access Journals (Sweden)

    Hayashi Nobuhiro

    2008-02-01

    Full Text Available Abstract Background The myelin sheath is a multilamellar membrane structure wrapped around the axon, enabling the saltatory conduction of nerve impulses in vertebrates. Myelin basic protein, one of the most abundant myelin-specific proteins, is an intrinsically disordered protein that has been shown to bind calmodulin. In this study, we focus on a 19-mer synthetic peptide from the predicted calmodulin-binding segment near the C-terminus of human myelin basic protein. Results The interaction of native human myelin basic protein with calmodulin was confirmed by affinity chromatography. The binding of the myelin basic protein peptide to calmodulin was tested with isothermal titration calorimetry (ITC in different temperatures, and Kd was observed to be in the low μM range, as previously observed for full-length myelin basic protein. Surface plasmon resonance showed that the peptide bound to calmodulin, and binding was accompanied by a conformational change; furthermore, gel filtration chromatography indicated a decrease in the hydrodynamic radius of calmodulin in the presence of the peptide. NMR spectroscopy was used to map the binding area to reside mainly within the hydrophobic pocket of the C-terminal lobe of calmodulin. The solution structure obtained by small-angle X-ray scattering indicates binding of the myelin basic protein peptide into the interlobal groove of calmodulin, while calmodulin remains in an extended conformation. Conclusion Taken together, our results give a detailed structural insight into the interaction of calmodulin with a C-terminal segment of a major myelin protein, the myelin basic protein. The used 19-mer peptide interacts mainly with the C-terminal lobe of calmodulin, and a conformational change accompanies binding, suggesting a novel mode of calmodulin-target protein interaction. Calmodulin does not collapse and wrap around the peptide tightly; instead, it remains in an extended conformation in the solution structure

  7. Possible basic and specific functions of plant uncoupling proteins (pUCP)

    Czech Academy of Sciences Publication Activity Database

    Ježek, Petr; Borecký, Jiří; Žáčková, Markéta; Costa, A. D. T.; Arruda, P.

    2001-01-01

    Roč. 21, č. 2 (2001), s. 237-245 ISSN 0144-8463 R&D Projects: GA ČR GA301/98/0568; GA AV ČR IAA5011106 Institutional research plan: CEZ:AV0Z5011922 Keywords : fatty acid-induced uncoupling * plant uncoupling mitochondrial protein * plant mitochondria Subject RIV: CE - Biochemistry Impact factor: 0.921, year: 2001

  8. The location of regions in guinea pig and bovine myelin basic proteins which induce experimental allergic encephalomyelitis in Lewis rats.

    Science.gov (United States)

    Martenson, R E; Levine, S; Sowindki, R

    1975-02-01

    Myelin basic proteins and peptides derived from them by limited cleavage with pepsin were tested for their ability to induce experimental allergic encephalomyelitis (EAE) in Lewis rats. The encephalitogenicity of the weakly active bovine protein was found to be associated with both halves of the molecule, peptides (1-88) and (89-169). Of the four smaller derivates of peptide (1-88), peptides (1-36), (43-88), (1-42), and (37-88), only the last two were active. This demonstrated that the overlap region consisting of residues 37-42 (sequence Asp-Ser-Leu-Gly-Arg-Phe) constitutes an encephalitogenic determinant. Of the two smaller derivatives of peptide (89-169), peptides (111-169) and (89-152), only the last was active. This indicated that the second encephalitogenic determinant begins between residues 88 and 111 and ends before residue 153. This region contains the sequence Leu-Ser-Leu-Ser-Arg-Phe (residues 108-113), which is strikingly similar to that of the first encephalitogenic determinant. Studies involving the extremely encephalitogenic guinea pig protein demonstrated that virtually all of the activity was recovered in the peptides corresponding to bovine peptides (37-88) and (43-88). These peptides, but not those comprising the remainder of the protein, were active in inhibiting the passive transfer of EAE with lymph node cells from donors immunized with guinea pig spinal cord.

  9. High performance aptamer affinity chromatography for single-step selective extraction and screening of basic protein lysozyme.

    Science.gov (United States)

    Han, Bin; Zhao, Chao; Yin, Junfa; Wang, Hailin

    2012-08-15

    A DNA aptamer based high-performance affinity chromatography is developed for selective extraction and screening of a basic protein lysozyme. First, a poly(glycidyl methacrylate-co-ethylene dimethacrylate) monolithic column was synthesized in situ by thermally initiated radical polymerization, and then an anti-lysozyme DNA aptamer was covalently immobilized on the surface of the monolith through a 16-atom spacer arm. The target protein lysozyme but non-target proteins can be trapped by the immobilized anti-lysozyme DNA aptamer. In contrast, lysozyme cannot be trapped by the immobilized oligodeoxynucleotide that does not contain the sequence of the anti-lysozyme DNA aptamer. The study clearly demonstrates the trapping of lysozyme by the immobilized anti-lysozyme DNA aptamer is mainly due to specific recognition rather than simple electrostatic interaction of positively charged protein and the negatively charged DNA. The inter-day precision was determined as 0.8% for migration time and 4.2% for peak area, respectively. By the use of aptamer affinity monolith, a screening strategy is developed to selectively extract lysozyme from chicken egg white, showing the advantages of high efficiency, low cost and ease-of-operation. Copyright © 2012 Elsevier B.V. All rights reserved.

  10. A novel antigen-toxin chimeric protein: myelin basic protein-pseudomonas exotoxin (MBP-PE 40) for treatment of experimental autoimmune encephalomyelitis.

    Science.gov (United States)

    Brenner, T; Steinberger, I; Soffer, D; Beraud, E; Ben-Nun, A; Lorberboum-Galski, H

    1999-06-01

    Myelin basic protein (MBP), is a major component of the central nervous system (CNS) myelin. MBP can stimulate T cells that migrate into the CNS, initiating a cascade of events that result in perivascular infiltration and demyelination. EAE is an inflammatory and demyelinating autoimmune disease of the CNS that serves as a model for the human disease Multiple Sclerosis (MS). Taking advantage of the fact that EAE can be mediated by T cells, able to recognize MBP or its peptides, we developed a new approach to target anti-MBP T cells by fusing an MBP-sequence to a toxin. In the new chimeric protein, an oligonucleotide coding for the guinea pig MBP encephalitogenic moiety (residues 68-88) was fused to a cDNA encoding a truncated form of the PE gene (PE40). The chimeric gene termed MBP-PE was expressed in E. coli and highly purified. MBP-PE chimeric protein was cytotoxic to various anti-MBP T cells. Moreover, treatment with the novel MBP-toxin blocked the clinical signs of EAE as well as CNS inflammation and demyelination. A chimeric protein such as MBP-PE40 presents a novel prototype of chimeric proteins, composed of antigen/peptide-toxin, that could prove to be an efficient and specific immunotherapeutic agent for autoimmune diseases in which a known antigen is involved.

  11. Focal cerebral ischemia induces increased myelin basic protein and growth-associated protein-43 gene transcription in peri-infarct areas in the rat brain

    DEFF Research Database (Denmark)

    Gregersen, R; Christensen, Thomas; Lehrmann, E

    2001-01-01

    Although oligodendrocytes are vulnerable to focal cerebral ischemia, remyelination of denuded or regenerating axons in the peri-infarct area has been observed in the central nervous system. We studied the expression of myelin basic protein (MBP), a major component of central nervous system myelin...... messenger RNA (mRNA) had disappeared by 24 h, whereas myelin protein, identified by MBP and myelin oligodendrocyte glycoprotein (MOG) immunohistochemistry, appeared structurally intact until day 3. Peri-infarct oligodendrocytes increased their expression of MBP mRNA from 24 h to maximal levels at day 7...... showed that increased expression of GAP-43 mRNA in neurons was concomitant to MBP mRNA upregulation in oligodendrocytes. While the mechanisms regulating oligodendrocyte survival and myelination signals are not clear at this point, axonal sprouting could putatively serve as a stimulus for the upregulation...

  12. Characterization and expression analysis of AH receptors in aquatic mammals and birds

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Eun-Young [Ehime Prefectural Institute of Public Health and Environmental Science, Matsuyama (Japan); Yasui, Tomoko; Hisato, Iwata; Shinsuke, Tanabe [Ehime Univ., Matsuyama (Japan)

    2004-09-15

    The magnitude of the risk that 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and related planar halogenated aromatic hydrocarbons (PHAHs) pose to the health of aquatic birds and mammals is uncertain, because of the lack of direct information on the sensitivity and toxicity to these chemicals. Exposure to PHAHs is speculated to produce toxicity through changes in the expression of genes involved in the control of cell growth and differentiation. These changes are initiated by the binding to the aryl hydrocarbon receptor (AHR), a ligand-dependent transcription factor. The AHR and its dimerization partner ARNT belong to the basic-helix-loop-helix/Per-ARNT-Sim (bHLH-PAS) family of transcriptional regulation proteins. The bHLH domain was involved in protein-DNA and protein-protein interactions, and the PAS domain forms a secondary dimerization surface for heteromeric interactions between AHR and ARNT. Although the presence and basic function of AHR are known to be conserved in most vertebrates, only a limited number of studies on the structure and functional diversity of AHR in aquatic mammals and birds have been reported, in spite of their high exposure to dioxins and other related chemicals. To understand the molecular mechanism of susceptibility to dioxin exposure and toxic effects that PHAHs pose in wild animals, we investigated the molecular and functional characterization of AHRs from aquatic mammals and birds. Initially, the AHR cDNAs from the livers of Baikal seal (Pusa sibirica), black-footed albatross (Diomedea nigripes) and common cormorant (Phalacrocorax carbo) were cloned and sequenced. We also clarified the tissue-specific expression pattern of AHR mRNA and the relationships among PHAHs, AHR and CYP expression levels in the liver of Baikal seals and common cormorants.

  13. An overview of the gene regulatory network controlling trichome development in the model plant, Arabidopsis

    Directory of Open Access Journals (Sweden)

    Sitakanta ePattanaik

    2014-06-01

    Full Text Available Trichomes are specialized epidermal cells located on aerial parts of plants and are associated with a wide array of biological processes. Trichomes protect plants from adverse conditions including UV light and herbivore attack and are also an important source of a number of phytochemicals. The simple unicellular trichomes of Arabidopsis serve as an excellent model to study molecular mechanism of cell differentiation and pattern formation in plants. The emerging picture suggests that the developmental process is controlled by a transcriptional network involving three major groups of transcription factors: the R2R3 MYB, basic helix-loop-helix (bHLH and WD40 repeat (WDR protein. These regulatory proteins form a trimeric activator complex that positively regulates trichome development. The single repeat R3 MYBs act as negative regulators of trichome development. They compete with the R2R3 MYBs to bind the bHLH factor and form a repressor complex. In addition to activator-repressor mechanism, a depletion mechanism may operate in parallel during trichome development. In this mechanism, the bHLH factor traps the WDR protein which results in depletion of WDR protein in neighboring cells. Consequently, the cells with high levels of bHLH and WDR proteins are developed into trichomes. A group of C2H2 zinc finger TFs has also been implicated in trichome development. Phytohormones, including gibberellins and jasmonic acid, play significant roles in this developmental process. Recently, microRNAs have been shown to be involved in trichome development. Furthermore, it has been demonstrated that the activities of the key regulatory proteins involved in trichome development are controlled by the 26S/ubiquitin proteasome system (UPS, highlighting the complexity of the regulatory network controlling this developmental process. To complement several excellent recent relevant reviews, this review focuses on the transcriptional network and hormonal interplay

  14. Analyses of loss-of-function mutations of the MITF gene suggest that haploinsufficiency is a cause of Waardenburg syndrome type 2A

    Energy Technology Data Exchange (ETDEWEB)

    Nobukuni, Yoshitaka; Watanabe, A.; Takeda, Kazushisa; Skarka, Hana; Tachibana, Masayoshi [National Inst. of Health, Bethesda, MD (United States)

    1996-07-01

    Waardenburg syndrome type 2 (WS2) is a dominantly inherited disorder characterized by a pigmentation anomaly and hearing impairment due to lack of melanocyte. Previous work has linked a subset of families with WS2 (WS2A) to the MITF gene that encodes a transcription factor with a basic-helix-loop-helix-leucine zipper (bHLH-Zip) motif and that is involved in melanocyte differentiation. Several splice-site and missense mutations have been reported in individuals affected with WS2A. In this report, we have identified two novel point mutations in the MITF gene in affected individuals from two different families with WS2A. The two mutations (C760{r_arrow}T and C895{r_arrow}T) create stop codons in exons 7 and 8, respectively. Corresponding mutant alleles predict the truncated proteins lacking HLH-Zip or Zip structure. To understand how these mutations cause WS2 in heterozygotes, we generated mutant MITF cDNAs and used them for DNA-binding and luciferase reporter assays. The mutated MITF proteins lose the DNA-binding activity and fail to transactivate the promoter of tyrosinase, a melanocyte-specific enzyme. However, these mutated proteins do not appear to interfere with the activity of wild-type MITF protein in these assays, indicating that they do not show a dominant-negative effect. These findings suggest that the phenotypes of the two families with WS2A in the present study are caused by loss-of-function mutations in one of the two alleles of the MITF gene, resulting in haploinsufficiency of the MITF protein, the protein necessary for normal development of melanocytes. 37 refs., 4 figs.

  15. Purification and characterization of elicitor protein from Phytophthora colocasiae and basic resistance in Colocasia esculenta.

    Science.gov (United States)

    Mishra, Ajay Kumar; Sharma, Kamal; Misra, Raj Shekhar

    2009-01-01

    An elicitor was identified in the fungus Phytophthora colocasiae. The molecular weight of the purified elicitor was estimated by means of gel filtration chromatography and SDS-PAGE and was estimated as 15kDa. Protease treatment severely reduced its activity, allowing the conclusion that the elicitor is proteinaceous. Infiltration of a few nanograms of this proteinaceous elicitor into taro leaves caused the formation of lesions that closely resemble hypersensitive response lesions. The elicitation of the cells was effective in the induction of the activity of lipoxygenase. Cellular damage, restricted to the infiltrated zone, occurred only several hours later, after the infiltration of the elicitor protein. After few days, systemic acquired resistance was also induced. Thus, taro plant cells that perceived the glycoprotein generated a cascade of signals acting at local, short, and long distances, and causing the coordinate expression of specific defence. The obtained results give important information regarding the plant-pathogen interactions, mainly as subsidy for taro improvement against Phytophthora leaf blight. 2008 Elsevier GmbH.

  16. Vaccination with DNA encoding an immunodominant myelin basic protein peptide targeted to Fc of immunoglobulin G suppresses experimental autoimmune encephalomyelitis.

    Science.gov (United States)

    Lobell, A; Weissert, R; Storch, M K; Svanholm, C; de Graaf, K L; Lassmann, H; Andersson, R; Olsson, T; Wigzell, H

    1998-05-04

    We explore here if vaccination with DNA encoding an autoantigenic peptide can suppress autoimmune disease. For this purpose we used experimental autoimmune encephalomyelitis (EAE), which is an autoaggressive disease in the central nervous system and an animal model for multiple sclerosis. Lewis rats were vaccinated with DNA encoding an encephalitogenic T cell epitope, guinea pig myelin basic protein peptide 68-85 (MBP68-85), before induction of EAE with MBP68-85 in complete Freund's adjuvant. Compared to vaccination with a control DNA construct, the vaccination suppressed clinical and histopathological signs of EAE, and reduced the interferon gamma production after challenge with MBP68-85. Targeting of the gene product to Fc of IgG was essential for this effect. There were no signs of a Th2 cytokine bias. Our data suggest that DNA vaccines encoding autoantigenic peptides may be useful tools in controlling autoimmune disease.

  17. Proteasome-mediated turnover of the transcriptional activator FIT is required for plant iron-deficiency responses.

    Science.gov (United States)

    Sivitz, Alicia; Grinvalds, Claudia; Barberon, Marie; Curie, Catherine; Vert, Grégory

    2011-06-01

    Plants display a number of responses to low iron availability in order to increase iron uptake from the soil. In the model plant Arabidopsis thaliana, the ferric-chelate reductase FRO2 and the ferrous iron transporter IRT1 control iron entry from the soil into the root epidermis. To maintain iron homeostasis, the expression of FRO2 and IRT1 is tightly controlled by iron deficiency at the transcriptional level. The basic helix-loop-helix (bHLH) transcription factor FIT represents the most upstream actor known in the iron-deficiency signaling pathway, and directly regulates the expression of the root iron uptake machinery genes FRO2 and IRT1. However, how FIT is controlled by iron and acts to activate transcription of its targets remains obscure. Here we show that FIT mRNA and endogenous FIT protein accumulate in Arabidopsis roots upon iron deficiency. However, using plants constitutively expressing FIT, we observed that FIT protein accumulation is reduced in iron-limited conditions. This post-transcriptional regulation of FIT is perfectly synchronized with the accumulation of endogenous FIT and IRT1 proteins, and therefore is part of the early responses to low iron. We demonstrated that such regulation affects FIT protein stability under iron deficiency as a result of 26S proteasome-dependent degradation. In addition, we showed that FIT post-translational regulation by iron is required for FRO2 and IRT1 gene expression. Taken together our results indicate that FIT transcriptional and post-translational regulations are integrated in plant roots to ensure that the positive regulator FIT accumulates as a short-lived protein following iron shortage, and to allow proper iron-deficiency responses. © 2011 The Authors. The Plant Journal © 2011 Blackwell Publishing Ltd.

  18. The quantitative assessment of the role played by basic amino acid clusters in the nuclear uptake of human ribosomal protein L7

    International Nuclear Information System (INIS)

    Tai, Lin-Ru; Chou, Chang-Wei; Lee, I-Fang; Kirby, Ralph; Lin, Alan

    2013-01-01

    In this study, we used a multiple copy (EGFP) 3 reporter system to establish a numeric nuclear index system to assess the degree of nuclear import. The system was first validated by a FRAP assay, and then was applied to evaluate the essential and multifaceted nature of basic amino acid clusters during the nuclear import of ribosomal protein L7. The results indicate that the sequence context of the basic cluster determines the degree of nuclear import, and that the number of basic residues in the cluster is irrelevant; rather the position of the pertinent basic residues is crucial. Moreover, it also found that the type of carrier protein used by basic cluster has a great impact on the degree of nuclear import. In case of L7, importin β2 or importin β3 are preferentially used by clusters with a high import efficiency, notwithstanding that other importins are also used by clusters with a weaker level of nuclear import. Such a preferential usage of multiple basic clusters and importins to gain nuclear entry would seem to be a common practice among ribosomal proteins in order to ensure their full participation in high rate ribosome synthesis. - Highlights: ► We introduce a numeric index system that represents the degree of nuclear import. ► The rate of nuclear import is dictated by the sequence context of the basic cluster. ► Importin β2 and β3 were mainly responsible for the N4 mediated nuclear import

  19. Transcriptome-Wide Identification and Expression Profiling Analysis of Chrysanthemum Trihelix Transcription Factors.

    Science.gov (United States)

    Song, Aiping; Wu, Dan; Fan, Qingqing; Tian, Chang; Chen, Sumei; Guan, Zhiyong; Xin, Jingjing; Zhao, Kunkun; Chen, Fadi

    2016-02-02

    Trihelix transcription factors are thought to feature a typical DNA-binding trihelix (helix-loop-helix-loop-helix) domain that binds specifically to the GT motif, a light-responsive DNA element. Members of the trihelix family are known to function in a number of processes in plants. Here, we characterize 20 trihelix family genes in the important ornamental plant chrysanthemum (Chrysanthemum morifolium). Based on transcriptomic data, 20 distinct sequences distributed across four of five groups revealed by a phylogenetic tree were isolated and amplified. The phylogenetic analysis also identified four pairs of orthologous proteins shared by Arabidopsis and chrysanthemum and five pairs of paralogous proteins in chrysanthemum. Conserved motifs in the trihelix proteins shared by Arabidopsis and chrysanthemum were analyzed using MEME, and further bioinformatic analysis revealed that 16 CmTHs can be targeted by 20 miRNA families and that miR414 can target 9 CmTHs. qPCR results displayed that most chrysanthemum trihelix genes were highly expressed in inflorescences, while 20 CmTH genes were in response to phytohormone treatments and abiotic stresses. This work improves our understanding of the various functions of trihelix gene family members in response to hormonal stimuli and stress.

  20. Delayed onset of experimental autoimmune encephalomyelitis in Olig1 deficient mice.

    Directory of Open Access Journals (Sweden)

    Xiaoli Guo

    Full Text Available BACKGROUND: Olig1 is a basic helix-loop-helix (bHLH transcription factor that is essential for oligodendrogenesis and efficient remyelination. However, its role in neurodegenerative disorders has not been well-elucidated. METHODOLOGY/PRINCIPAL FINDINGS: Here we investigated the effects of Olig1 deficiency on experimental autoimmune encephalomyelitis (EAE, an animal model of multiple sclerosis (MS. We show that the mean disease onset of myelin oligodendrocyte glycoprotein (MOG-induced EAE in Olig1(-/- mice is significantly slower than wide-type (WT mice (19.8 ± 2.2 in Olig1(-/- mice and 9.5 ± 0.3 days in WT mice. In addition, 10% of Olig1(-/- mice did not develop EAE by the end of the observation periods (60 days. The severity of EAE, the extent of demyelination, and the activation of microglial cells and astrocytes in spinal cords, were significantly milder in Olig1(-/- mice compared with WT mice in the early stage. Moreover, the visual function, as assessed by the second-kernel of multifocal electroretinograms, was better preserved, and the number of degenerating axons in the optic nerve was significantly reduced in Olig1(-/- mice. Interestingly, Olig1 deficiency had no effect on T cell response capability, however, it reduced the expression of myelin proteins such as MOG, myelin basic protein (MBP and myelin-associated glycoprotein (MAG. The expression of Olig2 remained unchanged in the optic nerve and brain, and it was reduced in the spinal cord of Olig1(-/- mice. CONCLUSIONS/SIGNIFICANCE: Our results suggest that the Olig1 signaling pathways may be involved in the incidence rate and the severity of neurological symptoms in MS.

  1. Solution structure of the microtubule-targeting COS domain of MID1.

    Science.gov (United States)

    Wright, Katharine M; Du, Haijuan; Dagnachew, Mesgana; Massiah, Michael A

    2016-08-01

    The human MID1 protein is required for the proper development during embryogenesis. Mutations of MID1 are associated with X-linked Opitz G syndrome, characterized by midline anomalies. MID1 associates with the microtubules and functions as an ubiquitin E3 ligase, targeting protein phosphatase 2A for ubiquitin-mediated regulation. The mechanism of microtubule association is not known. Recently, a 60-amino acid region termed the C-terminal subgroup One Signature (COS) box/domain was identified at the C-terminal end of the coiled-coil (CC) domain that facilitates microtubule localization. Insertion of the MID1 COS domain at the C-terminal end of the CC domain of a nonmicrotubule-associated TRIM protein confers microtubule localization. Here, we report the solution structure of the COS domain of MID1. The domain adopts a helix-loop-helix structure in which the N- and C-terminal ends are in close proximity. Hydrophobic residues stabilizing the interaction of the two α-helices form a central hydrophobic core. The loop separating the α-helices is structured, with two of its hydrophobic residues making contact with the central core. On the outer surface, positively charged residues form a distinct basic patch near the termini that we postulate is important for microtubule binding. A model of the structure of the preceding coiled-coil and COS domains (CC-COS) show that the COS domain forms a helical bundle at the C-terminal end of the CC domain similar to the spectrin-like fold observed with some known microtubule-binding proteins. Interestingly, the CC-COS domains bind to microtubules, demonstrating for the first time that MID1 can directly associate with the microtubules. Structural data are available in PDB database under the accession number 5IM8. © 2016 Federation of European Biochemical Societies.

  2. Insulin stimulates the expression of the SHARP-1 gene via multiple signaling pathways.

    Science.gov (United States)

    Takagi, K; Asano, K; Haneishi, A; Ono, M; Komatsu, Y; Yamamoto, T; Tanaka, T; Ueno, H; Ogawa, W; Tomita, K; Noguchi, T; Yamada, K

    2014-06-01

    The rat enhancer of split- and hairy-related protein-1 (SHARP-1) is a basic helix-loop-helix transcription factor. An issue of whether SHARP-1 is an insulin-inducible transcription factor was examined. Insulin rapidly increased the level of SHARP-1 mRNA both in vivo and in vitro. Then, signaling pathways involved with the increase of SHARP-1 mRNA by insulin were determined in H4IIE rat hepatoma cells. Pretreatments with LY294002, wortmannin, and staurosporine completely blocked the induction effect, suggesting the involvement of both phosphoinositide 3-kinase (PI 3-K) and protein kinase C (PKC) pathways. In fact, overexpression of a dominant negative form of atypical protein kinase C lambda (aPKCλ) significantly decreased the induction of the SHARP-1 mRNA. In addition, inhibitors for the small GTPase Rac or Jun N-terminal kinase (JNK) also blocked the induction of SHARP-1 mRNA by insulin. Overexpression of a dominant negative form of Rac1 prevented the activation by insulin. Furthermore, actinomycin D and cycloheximide completely blocked the induction of SHARP-1 mRNA by insulin. Finally, when a SHARP-1 expression plasmid was transiently transfected with various reporter plasmids into H4IIE cells, the promoter activity of PEPCK reporter plasmid was specifically decreased. Thus, we conclude that insulin induces the SHARP-1 gene expression at the transcription level via a both PI 3-K/aPKCλ/JNK- and a PI 3-K/Rac/JNK-signaling pathway; protein synthesis is required for this induction; and that SHARP-1 is a potential repressor of the PEPCK gene expression. © Georg Thieme Verlag KG Stuttgart · New York.

  3. Cloning and functional characterisation of avian transcription factor E2A

    Directory of Open Access Journals (Sweden)

    Meyer Kerstin B

    2004-06-01

    Full Text Available Abstract Background During B lymphocyte development the E2A gene is a critical regulator of cell proliferation and differentiation. With regards to the immunoglobulin genes the E2A proteins contribute to the regulation of gene rearrangement, expression and class switch recombination. We are now using the chicken cell line DT40 as a model system to further analyse the function of E2A. Results Here we report the cloning and functional analysis of the transcription factor E2A from chicken. Using RACE PCR on the chicken lymphoma cell line DT40 we have isolated full-length clones for the two E2A splice variants E12 and E47. Sequence conservation between the human and chicken proteins is extensive: the basic-helix-loop-helix DNA binding domain of human and chicken E47 and E12 are 93% and 92% identical, respectively. In addition high levels of conservation are seen in activation domain I, the potential NLS and the ubiquitin ligase interaction domain. E2A is expressed in a variety of tissues in chicken, with higher levels of expression in organs rich in immune cells. We demonstrate that chicken E12 and E47 proteins are strong transcriptional activators whose function depends on the presence of activation domain I. As in mammals, the dominant negative proteins Id1 and Id3 can inhibit the function of chicken E47. Conclusions The potential for homologous recombination in DT40 allows the genetic dissection of biochemical pathways in somatic cells. With the cloning of avian E2A and the recent description of an in vitro somatic hypermutation assay in this cell line, it should now be possible to dissect the potential role of E2A in the regulation of somatic hypermutation and gene conversion.

  4. Calcium-dependent binding of Myc to calmodulin

    Science.gov (United States)

    Raffeiner, Philipp; Schraffl, Andrea; Schwarz, Thomas; Röck, Ruth; Ledolter, Karin; Hartl, Markus; Konrat, Robert; Stefan, Eduard; Bister, Klaus

    2017-01-01

    The bHLH-LZ (basic region/helix-loop-helix/leucine zipper) oncoprotein Myc and the bHLH-LZ protein Max form a binary transcription factor complex controlling fundamental cellular processes. Deregulated Myc expression leads to neoplastic transformation and is a hallmark of most human cancers. The dynamics of Myc transcription factor activity are post-translationally coordinated by defined protein-protein interactions. Here, we present evidence for a second messenger controlled physical interaction between the Ca2+ sensor calmodulin (CaM) and all Myc variants (v-Myc, c-Myc, N-Myc, and L-Myc). The predominantly cytoplasmic Myc:CaM interaction is Ca2+-dependent, and the binding site maps to the conserved bHLH domain of Myc. Ca2+-loaded CaM binds the monomeric and intrinsically disordered Myc protein with high affinity, whereas Myc:Max heterodimers show less, and Max homodimers no affinity for CaM. NMR spectroscopic analyses using alternating mixtures of 15N-labeled and unlabeled preparations of CaM and a monomeric Myc fragment containing the bHLH-LZ domain corroborate the biochemical results on the Myc:CaM interaction and confirm the interaction site mapping. In electrophoretic mobility shift assays, addition of CaM does not affect high-affinity DNA-binding of Myc:Max heterodimers. However, cell-based reporter analyses and cell transformation assays suggest that increasing CaM levels enhance Myc transcriptional and oncogenic activities. Our results point to a possible involvement of Ca2+ sensing CaM in the fine-tuning of Myc function. PMID:27926480

  5. Presentation of myelin basic protein by normal guinea-pig brain endothelial cells and its relevance to experimental allergic encephalomyelitis.

    Science.gov (United States)

    Wilcox, C E; Healey, D G; Baker, D; Willoughby, D A; Turk, J L

    1989-08-01

    Previous studies have shown that endothelial cells in the central nervous system (CNS) of normal guinea-pigs constitutively express certain MHC class II determinants, whilst the expression of other determinants is apparent during the acute phase of chronic relapsing experimental allergic encephalomyelitis (CREAE). The expression of MHC class II determinants is retained by endothelial cells derived from normal guinea-pig brain tissue and maintained in culture. This present study demonstrates that the MHC class II molecules on these cells can be recognized by allogeneic lymphocytes, resulting in a proliferative response which is enhanced by the addition of exogenous IL-2. The endothelial cells were incapable of presenting either purified protein derivative or ovalbumin, but they could present autologous myelin basic protein (MBP), an encephalitogen implicated in the pathogenesis of EAE. The resulting lymphocyte proliferative response was of the same magnitude as that obtained when a control population of macrophages was used to present MBP. These results, therefore, suggest that cerebrovascular endothelia have the potential to play a role in the pathogenesis of EAE.

  6. The bHLH Transcription Factor HBI1 Mediates the Trade-Off between Growth and Pathogen-Associated Molecular Pattern–Triggered Immunity in Arabidopsis[W][OPEN

    Science.gov (United States)

    Fan, Min; Bai, Ming-Yi; Kim, Jung-Gun; Wang, Tina; Oh, Eunkyoo; Chen, Lawrence; Park, Chan Ho; Son, Seung-Hyun; Kim, Seong-Ki; Mudgett, Mary Beth; Wang, Zhi-Yong

    2014-01-01

    The trade-off between growth and immunity is crucial for survival in plants. However, the mechanism underlying growth-immunity balance has remained elusive. The PRE-IBH1-HBI1 tripartite helix-loop-helix/basic helix-loop-helix module is part of a central transcription network that mediates growth regulation by several hormonal and environmental signals. Here, genome-wide analyses of HBI1 target genes show that HBI1 regulates both overlapping and unique targets compared with other DNA binding components of the network in Arabidopsis thaliana, supporting a role in specifying network outputs and fine-tuning feedback regulation. Furthermore, HBI1 negatively regulates a subset of genes involved in immunity, and pathogen-associated molecular pattern (PAMP) signals repress HBI1 transcription. Constitutive overexpression and loss-of-function experiments show that HBI1 inhibits PAMP-induced growth arrest, defense gene expression, reactive oxygen species production, and resistance to pathogen. These results show that HBI1, as a component of the central growth regulation circuit, functions as a major node of crosstalk that mediates a trade-off between growth and immunity in plants. PMID:24550223

  7. The bHLH transcription factor HBI1 mediates the trade-off between growth and pathogen-associated molecular pattern-triggered immunity in Arabidopsis.

    Science.gov (United States)

    Fan, Min; Bai, Ming-Yi; Kim, Jung-Gun; Wang, Tina; Oh, Eunkyoo; Chen, Lawrence; Park, Chan Ho; Son, Seung-Hyun; Kim, Seong-Ki; Mudgett, Mary Beth; Wang, Zhi-Yong

    2014-02-01

    The trade-off between growth and immunity is crucial for survival in plants. However, the mechanism underlying growth-immunity balance has remained elusive. The PRE-IBH1-HBI1 tripartite helix-loop-helix/basic helix-loop-helix module is part of a central transcription network that mediates growth regulation by several hormonal and environmental signals. Here, genome-wide analyses of HBI1 target genes show that HBI1 regulates both overlapping and unique targets compared with other DNA binding components of the network in Arabidopsis thaliana, supporting a role in specifying network outputs and fine-tuning feedback regulation. Furthermore, HBI1 negatively regulates a subset of genes involved in immunity, and pathogen-associated molecular pattern (PAMP) signals repress HBI1 transcription. Constitutive overexpression and loss-of-function experiments show that HBI1 inhibits PAMP-induced growth arrest, defense gene expression, reactive oxygen species production, and resistance to pathogen. These results show that HBI1, as a component of the central growth regulation circuit, functions as a major node of crosstalk that mediates a trade-off between growth and immunity in plants.

  8. Hes1 potentiates T cell lymphomagenesis by up-regulating a subset of notch target genes.

    Directory of Open Access Journals (Sweden)

    Darryll D Dudley

    2009-08-01

    Full Text Available Hairy/Enhancer of Split (Hes proteins are targets of the Notch signaling pathway and make up a class of basic helix-loop-helix (bHLH proteins that function to repress transcription. Data from Hes1 deficient mice suggested that Hes1, like Notch1, is necessary for the progression of early T cell progenitors. Constitutive activation of Notch is known to cause T cell leukemia or lymphoma but whether Hes1 has any oncogenic activity is not known.We generated mice carrying a Hes1 transgene under control of the proximal promote of the lck gene. Hes1 expression led to a reduction in numbers of total thymocytes, concomitant with the increased percentage and number of immature CD8+ (ISP T cells and sustained CD25 expression in CD4+CD8+ double positive (DP thymocytes. Hes1 transgenic mice develop thymic lymphomas at about 20 weeks of age with a low penetrance. However, expression of Hes1 significantly shortens the latency of T cell lymphoma developed in Id1 transgenic mice, where the function of bHLH E proteins is inhibited. Interestingly, Hes1 increased expression of a subset of Notch target genes in pre-malignant ISP and DP thymocytes, which include Notch1, Notch3 and c-myc, thus suggesting a possible mechanism for lymphomagenesis.We have demonstrated for the first time that Hes1 potentiates T cell lymphomagenesis, by up-regulating a subset of Notch target genes and by causing an accumulation of ISP thymocytes particularly vulnerable to oncogenic transformation.

  9. Hippocalcin Is Required for Astrocytic Differentiation through Activation of Stat3 in Hippocampal Neural Precursor Cells.

    Directory of Open Access Journals (Sweden)

    Min-Jeong Kang

    2016-10-01

    Full Text Available Hippocalcin (Hpca is a neuronal calcium sensor protein expressed in the mammalian brain. However, its function in neural stem/precursor cells has not yet been studied. Here, we clarify the function of Hpca in astrocytic differentiation in hippocampal neural precursor cells (HNPCs. When we overexpressed Hpca in HNPCs in the presence or absence of bFGF, expression levels of nerve-growth factors such as neurotrophin-3 (NT-3, neurotrophin-4/5 (NT-4/5 and brain-derived neurotrophic factor (BDNF, together with the proneural basic helix loop helix (bHLH transcription factors neuroD and neurogenin 1 (ngn1, increased significantly. In addition, there was an increase in the number of cells expressing glial fibrillary acidic protein (GFAP, an astrocyte marker, and in dendrite outgrowth, indicating astrocytic differentiation of the HNPCs. Downregulation of Hpca by transfection with Hpca siRNA reduced expression of NT-3, NT-4/5, BDNF, neuroD and ngn1 as well as levels of GFAP protein. Furthermore, overexpression of Hpca increased the phosphorylation of STAT3 (Ser727, and this effect was abolished by treatment with a STAT3 inhibitor (S3I-201, suggesting that STAT3 (Ser727 activation is involved in Hpca-mediated astrocytic differentiation. As expected, treatment with Stat3 siRNA or STAT3 inhibitor caused a complete inhibition of astrogliogenesis induced by Hpca overexpression. Taken together, this is the first report to show that Hpca, acting through Stat3, has an important role in the expression of neurotrophins and proneural bHLH transcription factors, and that it is an essential regulator of astrocytic differentiation and dendrite outgrowth in HNPCs.

  10. A novel Zea mays ssp. mexicana L. MYC-type ICE-like transcription factor gene ZmmICE1, enhances freezing tolerance in transgenic Arabidopsis thaliana.

    Science.gov (United States)

    Lu, Xiang; Yang, Lei; Yu, Mengyuan; Lai, Jianbin; Wang, Chao; McNeil, David; Zhou, Meixue; Yang, Chengwei

    2017-04-01

    The annual Zea mays ssp. mexicana L., a member of the teosinte group, is a close wild relative of maize and thus can be effectively used in maize improvement. In this study, an ICE-like gene, ZmmICE1, was isolated from a cDNA library of RNA-Seq from cold-treated seedling tissues of Zea mays ssp. mexicana L. The deduced protein of ZmmICE1 contains a highly conserved basic helix-loop-helix (bHLH) domain and C-terminal region of ICE-like proteins. The ZmmICE1 protein localizes to the nucleus and shows sumoylation when expressed in an Escherichia coli reconstitution system. In addition, yeast one hybrid assays indicated that ZmmICE1 has transactivation activities. Moreover, ectopic expression of ZmmICE1 in the Arabidopsis ice1-2 mutant increased freezing tolerance. The ZmmICE1 overexpressed plants showed lower electrolyte leakage (EL), reduced contents of malondialdehyde (MDA). The expression of downstream cold related genes of Arabidopsis C-repeat-binding factors (AtCBF1, AtCBF2 and AtCBF3), cold-responsive genes (AtCOR15A and AtCOR47), kinesin-1 member gene (AtKIN1) and responsive to desiccation gene (AtRD29A) was significantly induced when compared with wild type under low temperature treatment. Taken together, these results indicated that ZmmICE1 is the homolog of Arabidopsis inducer of CBF expression genes (AtICE1/2) and plays an important role in the regulation of freezing stress response. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  11. Autoantibodies to myelin basic protein (MBP) in healthy individuals and in patients with multiple sclerosis: a role in regulating cytokine responses to MBP

    DEFF Research Database (Denmark)

    Hedegaard, Chris J; Chen, Ning; Sellebjerg, Finn

    2009-01-01

    Anti-myelin basic protein (-MBP) autoantibodies have generally been considered to be absent from sera from healthy individuals, but to be detectable in sera from some patients with multiple sclerosis (MS). However, their pathogenic role is uncertain. We demonstrate the presence of MBP-reactive au......Anti-myelin basic protein (-MBP) autoantibodies have generally been considered to be absent from sera from healthy individuals, but to be detectable in sera from some patients with multiple sclerosis (MS). However, their pathogenic role is uncertain. We demonstrate the presence of MBP...

  12. Effects of endurance exercise on expressions of glial fibrillary acidic protein and myelin basic protein in developing rats with maternal infection-induced cerebral palsy

    Science.gov (United States)

    Kim, Kijeong; Shin, Mal-Soon; Cho, Han-Sam; Kim, Young-Pyo

    2014-01-01

    Periventricular leukomalacia (PVL) is a common white matter lesion affecting the neonatal brain. PVL is closely associated with cerebral palsy (CP) and characterized by increase in the number of astrocytes, which can be detected by positivity for glial fibrillary acidic protein (GFAP). Change in myelin basic protein (MBP) is an early sign of white matter abnormality. Maternal or placental infection can damage the neonatal brain. In the present study, we investigated the effects of treadmill walking exercise on GFAP and MBP expressions in rats with maternal lipopolysaccharide (LPS)-induced PVL. Immunohistochemistry was performed for the detection of GFAP and MBP. The present results showed that intracervical maternal LPS injection during pregnancy increased GFAP expression in the striatum and decreased MBP expression in the corpus callosum of rats. The results also showed that treadmill walking exercise suppressed GFAP expression and enhanced MBP expression in the brains of rats with maternal LPS-induced PVL. The present study revealed that treadmill walking exercise is effective for the suppressing astrogliosis and hypomyelination associated with PVL. Here in this study, we showed that treadmill walking exercise may be effective therapeutic strategy for alleviating the detrimental effects of CP. PMID:24678499

  13. A fusion protein consisting of IL-16 and the encephalitogenic peptide of myelin basic protein constitutes an antigen-specific tolerogenic vaccine that inhibits experimental autoimmune encephalomyelitis.

    Science.gov (United States)

    Mannie, Mark D; Abbott, Derek J

    2007-08-01

    To test a novel concept for the generation of tolerogenic vaccines, fusion proteins were constructed encompassing a tolerogenic or biasing cytokine and the major encephalitogenic peptide of guinea pig myelin basic protein (GPMBP; i.e., neuroantigen or NAg). The cytokine domain was predicted to condition APC while simultaneously targeting the covalently linked encephalitogenic peptide to the MHC class II Ag processing pathway of those conditioned APC. Rats were given three s.c. injections of cytokine-NAg in saline 1-2 wk apart and then at least 1 wk later were challenged with NAg in CFA. The rank order of tolerogenic activity in the Lewis rat model of EAE was NAgIL16 > IL2NAg > IL1RA-NAg, IL13NAg >or= IL10NAg, GPMBP, GP69-88, and saline. NAgIL16 was also an effective inhibitor of experimental autoimmune encephalomyelitis when administered after an encephalitogenic challenge during the onset of clinical signs. Covalent linkage of the NAg and IL-16 was required for inhibition of experimental autoimmune encephalomyelitis. These data identify IL-16 as an optimal cytokine partner for the generation of tolerogenic vaccines and indicate that such vaccines may serve as Ag-specific tolerogens for the treatment of autoimmune disease.

  14. Introducing Pitt-Hopkins syndrome-associated mutations of TCF4 to Drosophila daughterless

    Directory of Open Access Journals (Sweden)

    Laura Tamberg

    2015-12-01

    Full Text Available Pitt-Hopkins syndrome (PTHS is caused by haploinsufficiency of Transcription factor 4 (TCF4, one of the three human class I basic helix-loop-helix transcription factors called E-proteins. Drosophila has a single E-protein, Daughterless (Da, homologous to all three mammalian counterparts. Here we show that human TCF4 can rescue Da deficiency during fruit fly nervous system development. Overexpression of Da or TCF4 specifically in adult flies significantly decreases their survival rates, indicating that these factors are crucial even after development has been completed. We generated da transgenic fruit fly strains with corresponding missense mutations R578H, R580W, R582P and A614V found in TCF4 of PTHS patients and studied the impact of these mutations in vivo. Overexpression of wild type Da as well as human TCF4 in progenitor tissues induced ectopic sensory bristles and the rough eye phenotype. By contrast, overexpression of DaR580W and DaR582P that disrupt DNA binding reduced the number of bristles and induced the rough eye phenotype with partial lack of pigmentation, indicating that these act dominant negatively. Compared to the wild type, DaR578H and DaA614V were less potent in induction of ectopic bristles and the rough eye phenotype, respectively, suggesting that these are hypomorphic. All studied PTHS-associated mutations that we introduced into Da led to similar effects in vivo as the same mutations in TCF4 in vitro. Consequently, our Drosophila models of PTHS are applicable for further studies aiming to unravel the molecular mechanisms of this disorder.

  15. Proline isomerase Pin1 represses terminal differentiation and myocyte enhancer factor 2C function in skeletal muscle cells.

    Science.gov (United States)

    Magli, Alessandro; Angelelli, Cecilia; Ganassi, Massimo; Baruffaldi, Fiorenza; Matafora, Vittoria; Battini, Renata; Bachi, Angela; Messina, Graziella; Rustighi, Alessandra; Del Sal, Giannino; Ferrari, Stefano; Molinari, Susanna

    2010-11-05

    Reversible proline-directed phosphorylation at Ser/Thr-Pro motifs has an essential role in myogenesis, a multistep process strictly regulated by several signaling pathways that impinge on two families of myogenic effectors, the basic helix-loop-helix myogenic transcription factors and the MEF2 (myocyte enhancer factor 2) proteins. The question of how these signals are deciphered by the myogenic effectors remains largely unaddressed. In this study, we show that the peptidyl-prolyl isomerase Pin1, which catalyzes the isomerization of phosphorylated Ser/Thr-Pro peptide bonds to induce conformational changes of its target proteins, acts as an inhibitor of muscle differentiation because its knockdown in myoblasts promotes myotube formation. With the aim of clarifying the mechanism of Pin1 function in skeletal myogenesis, we investigated whether MEF2C, a critical regulator of the myogenic program that is the end point of several signaling pathways, might serve as a/the target for the inhibitory effects of Pin1 on muscle differentiation. We show that Pin1 interacts selectively with phosphorylated MEF2C in skeletal muscle cells, both in vitro and in vivo. The interaction with Pin1 requires two novel critical phospho-Ser/Thr-Pro motifs in MEF2C, Ser(98) and Ser(110), which are phosphorylated in vivo. Overexpression of Pin1 decreases MEF2C stability and activity and its ability to cooperate with MyoD to activate myogenic conversion. Collectively, these findings reveal a novel role for Pin1 as a regulator of muscle terminal differentiation and suggest that Pin1-mediated repression of MEF2C function could contribute to this function.

  16. Identification of anthocyanin biosynthesis related microRNAs in a distinctive Chinese radish (Raphanus sativus L.) by high-throughput sequencing.

    Science.gov (United States)

    Sun, Yuyan; Qiu, Yang; Duan, Mengmeng; Wang, Jinglei; Zhang, Xiaohui; Wang, Haiping; Song, Jiangping; Li, Xixiang

    2017-02-01

    Anthocyanins are widely distributed water-soluble phytochemical pigments belonging to the flavonoid group. To date, limited knowledge is available about the regulatory roles of miRNAs in anthocyanin biosynthesis in plants. To identify the miRNAs associated with anthocyanin biosynthesis in radish, five small RNA (sRNA) libraries constructed from 'Xinlimei' radish roots at 11, 21, 44, 56 and 73 days (d) were examined using high-throughput sequencing technology. A total of 102.02 million (M) clean reads were generated, from which 483 known and 1415 novel miRNAs were identified. Combined with target prediction and annotation, 72 differentially expressed miRNAs (52 known and 20 novel miRNAs) were more likely to participate in anthocyanin biosynthesis. Several target genes for these miRNAs encode a few transcription factors, including Myb domain (MYB), basic helix-loop-helix (bHLH), WD40 repeat, squamosa promoter binding protein like (SPL), auxin response factor (ARF), ethylene insensitive 3 (EIN3), WRKY and MADS-box proteins. Furthermore, the expression patterns of some anthocyanin biosynthesis related miRNAs and their corresponding targets were validated by RT-qPCR. Based on the characterization of anthocyanin biosynthesis related miRNAs and their target genes, a putative miRNA-target module regulating anthocyanin biosynthesis was proposed. This study represents the first genome-wide identification of miRNAs associated with anthocyanin biosynthesis in radish, and provides insights into the molecular mechanisms underlying regulation of anthocyanin biosynthesis in radish and other crops.

  17. Angiopoietin-2 is a direct transcriptional target of TAL1, LYL1 and LMO2 in endothelial cells.

    Science.gov (United States)

    Deleuze, Virginie; El-Hajj, Rawan; Chalhoub, Elias; Dohet, Christiane; Pinet, Valérie; Couttet, Philippe; Mathieu, Danièle

    2012-01-01

    The two related basic helix-loop-helix, TAL1 and LYL1, and their cofactor LIM-only-2 protein (LMO2) are present in blood and endothelial cells. While their crucial role in early hematopoiesis is well established, their function in endothelial cells and especially in angiogenesis is less understood. Here, we identified ANGIOPOIETIN-2 (ANG-2), which encodes a major regulator of angiogenesis, as a direct transcriptional target of TAL1, LYL1 and LMO2. Knockdown of any of the three transcription factors in human blood and lymphatic endothelial cells caused ANG-2 mRNA and protein down-regulation. Transient transfections showed that the full activity of the ANG-2 promoter required the integrity of a highly conserved Ebox-GATA composite element. Accordingly, chromatin immunoprecipitation assays demonstrated that TAL1, LYL1, LMO2 and GATA2 occupied this region of ANG-2 promoter in human endothelial cells. Furthermore, we showed that LMO2 played a central role in assembling TAL1-E47, LYL1-LYL1 or/and LYL1-TAL1 dimers with GATA2. The resulting complexes were able to activate endogenous ANG-2 expression in endothelial cells as well as in non-endothelial cells. Finally, we showed that ANG-2 gene activation during angiogenesis concurred with the up-regulation of TAL1 and LMO2. Altogether, we identified ANG-2 as a bona fide target gene of LMO2-complexes with TAL1 and/or LYL1, highlighting a new function of the three hematopoietic factors in the endothelial lineage.

  18. Expression Differences of Pigment Structural Genes and Transcription Factors Explain Flesh Coloration in Three Contrasting Kiwifruit Cultivars

    Directory of Open Access Journals (Sweden)

    Yanfei Liu

    2017-09-01

    Full Text Available Fruits of kiwifruit cultivars (Actinidia chinensis and A. deliciosa generally have green or yellow flesh when ripe. A small number of genotypes have red flesh but this coloration is usually restricted to the inner pericarp. Three kiwifruit cultivars having red (‘Hongyang’, or yellow (‘Jinnong-2’, or green (‘Hayward’ flesh were investigated for their color characteristics and pigment contents during development and ripening. The results show the yellow of the ‘Jinnong-2’ fruit is due to the combined effects of chlorophyll degradation and of beta-carotene accumulation. The red inner pericarps of ‘Hongyang’ fruit are due to anthocyanin accumulation. Expression differences of the pathway genes in the inner pericarps of the three different kiwifruits suggest that stay-green (SGR controls the degradation of chlorophylls, while lycopene beta-cyclase (LCY-β controls the biosynthesis of beta-carotene. The abundance of anthocyanin in the inner pericarps of the ‘Hongyang’ fruit is the results of high expressions of UDP flavonoid glycosyltransferases (UFGT. At the same time, expressions of anthocyanin transcription factors show that AcMYBF110 expression parallels changes in anthocyanin concentration, so seems to be a key R2R3 MYB, regulating anthocyanin biosynthesis. Further, transient color assays reveal that AcMYBF110 can autonomously induce anthocyanin accumulation in Nicotiana tabacum leaves by activating the transcription of dihydroflavonol 4-reductase (NtDFR, anthocyanidin synthase (NtANS and NtUFGT. For basic helix-loop-helix proteins (bHLHs and WD-repeat proteins (WD40s, expression differences show these may depend on AcMYBF110 forming a MYB-bHLH-WD40 complex to regulate anthocyanin biosynthesis, instead of it having a direct involvement.

  19. bHLH106 Integrates Functions of Multiple Genes through Their G-Box to Confer Salt Tolerance on Arabidopsis.

    Science.gov (United States)

    Ahmad, Aftab; Niwa, Yasuo; Goto, Shingo; Ogawa, Takeshi; Shimizu, Masanori; Suzuki, Akane; Kobayashi, Kyoko; Kobayashi, Hirokazu

    2015-01-01

    An activation-tagging methodology was applied to dedifferentiated calli of Arabidopsis to identify new genes involved in salt tolerance. This identified salt tolerant callus 8 (stc8) as a gene encoding the basic helix-loop-helix transcription factor bHLH106. bHLH106-knockout (KO) lines were more sensitive to NaCl, KCl, LiCl, ABA, and low temperatures than the wild-type. Back-transformation of the KO line rescued its phenotype, and over-expression (OX) of bHLH106 in differentiated plants exhibited tolerance to NaCl. Green fluorescent protein (GFP) fused with bHLH106 revealed that it was localized to the nucleus. Prepared bHLH106 protein was subjected to electrophoresis mobility shift assays against E-box sequences (5'-CANNTG-3'). The G-box sequence 5'-CACGTG-3' had the strongest interaction with bHLH106. bHLH106-OX lines were transcriptomically analyzed, and resultant up- and down-regulated genes selected on the criterion of presence of a G-box sequence. There were 198 genes positively regulated by bHLH106 and 36 genes negatively regulated; these genes possessed one or more G-box sequences in their promoter regions. Many of these genes are known to be involved in abiotic stress response. It is concluded that bHLH106 locates at a branching point in the abiotic stress response network by interacting directly to the G-box in genes conferring salt tolerance on plants.

  20. bHLH106 Integrates Functions of Multiple Genes through Their G-Box to Confer Salt Tolerance on Arabidopsis.

    Directory of Open Access Journals (Sweden)

    Aftab Ahmad

    Full Text Available An activation-tagging methodology was applied to dedifferentiated calli of Arabidopsis to identify new genes involved in salt tolerance. This identified salt tolerant callus 8 (stc8 as a gene encoding the basic helix-loop-helix transcription factor bHLH106. bHLH106-knockout (KO lines were more sensitive to NaCl, KCl, LiCl, ABA, and low temperatures than the wild-type. Back-transformation of the KO line rescued its phenotype, and over-expression (OX of bHLH106 in differentiated plants exhibited tolerance to NaCl. Green fluorescent protein (GFP fused with bHLH106 revealed that it was localized to the nucleus. Prepared bHLH106 protein was subjected to electrophoresis mobility shift assays against E-box sequences (5'-CANNTG-3'. The G-box sequence 5'-CACGTG-3' had the strongest interaction with bHLH106. bHLH106-OX lines were transcriptomically analyzed, and resultant up- and down-regulated genes selected on the criterion of presence of a G-box sequence. There were 198 genes positively regulated by bHLH106 and 36 genes negatively regulated; these genes possessed one or more G-box sequences in their promoter regions. Many of these genes are known to be involved in abiotic stress response. It is concluded that bHLH106 locates at a branching point in the abiotic stress response network by interacting directly to the G-box in genes conferring salt tolerance on plants.

  1. Characterization of hey bHLH genes in teleost fish.

    Science.gov (United States)

    Winkler, Christoph; Elmasri, Harun; Klamt, Barbara; Volff, Jean-Nicolas; Gessler, Manfred

    2003-11-01

    Hairy-related basic helix-loop-helix (bHLH) transcription factors are targets of Delta-Notch signaling and represent essential components for a number of cell fate decisions during vertebrate embryogenesis. Hey genes encode a subfamily of hairy-related proteins that have been implicated in processes like somitogenesis, blood vessel and heart development. We have identified and characterized hey genes in three teleost fish lineages using degenerate PCR and database searches. Phylogenetic analysis of Hey proteins suggests a complex pattern of evolution with high divergence of hey2 in Takifugu rubripes (Fugu, Japanese pufferfish) and possibly loss in the related Tetraodon nigroviridis (the freshwater pufferfish). In addition, duplication of hey1 in both pufferfishes, Fugu and Tetraodon, was observed. Conversely, zebrafish (Danio rerio) has the same complement of three hey genes as known from mammals. All three hey genes show much more restricted gene expression profiles in zebrafish when compared to mouse. Importantly, while all three murine Hey genes are expressed in overlapping patterns in the presomitic mesoderm (PSM) and somites, in zebrafish only hey1 shows PSM and somite expression in a highly dynamic fashion. Therefore, while overlapping expression might account for redundancy of hey function in higher vertebrates, this is unlikely to be the case in zebrafish. In deltaD (dlD) deficient after-eight zebrafish mutants, the dynamic expression of hey1 in the PSM is impaired and completely lost in newly formed somitomeres. Overexpression of dlD on the other hand results in the ectopic expression of hey1 in the axial mesoderm. Hence, hey1 represents a target of Delta-Notch signaling dynamically expressed during somite formation in zebrafish.

  2. Twist-1 Up-Regulation in Carcinoma Correlates to Poor Survival

    Directory of Open Access Journals (Sweden)

    Alimujiang Wushou

    2014-11-01

    Full Text Available Epithelial-to-mesenchymal transition (EMT facilitates tumor metastasis. Twist is a basic helix-loop-helix protein that modulates many target genes through E-box-responsive elements. There are two twist-like proteins, Twist-1 and Twist-2, sharing high structural homology in mammals. Twist-1 was found to be a key factor in the promotion of metastasis of cancer cells, and is known to induce EMT. Twist-1 participation in carcinoma progression and metastasis has been reported in a variety of tumors. However, controversy exists concerning the correlation between Twist-1 and prognostic value with respect to carcinoma. A systematic review and meta-analysis were performed to determine whether the expression of Twist-1 was associated with the prognosis of carcinoma patients. This analysis included 17 studies: four studies evaluated lung cancer, three evaluated head and neck cancer, two evaluated breast cancer, two evaluated esophageal cancer, two evaluated liver cancer and one each evaluated osteosarcoma, bladder, cervical and ovarian cancer. A total of 2006 patients were enrolled in these studies, and the median trial sample size was 118 patients. Twist-1 expression was associated with worse overall survival (OS at both 3 years (hazard ratio “HR” for death = 2.13, 95% CI = 1.86 to 2.45, p < 0.001 and 5 years (HR for death = 2.01, 95% CI = 1.76 to 2.29, p < 0.001. Expression of Twist-1 is associated with worse survival in carcinoma.

  3. Adenosine Triphosphate (ATP Is a Candidate Signaling Molecule in the Mitochondria-to-Nucleus Retrograde Response Pathway

    Directory of Open Access Journals (Sweden)

    Zhengchang Liu

    2013-03-01

    Full Text Available Intracellular communication from the mitochondria to the nucleus is achieved via the retrograde response. In budding yeast, the retrograde response, also known as the RTG pathway, is regulated positively by Rtg1, Rtg2, Rtg3 and Grr1 and negatively by Mks1, Lst8 and two 14-3-3 proteins, Bmh1/2. Activation of retrograde signaling leads to activation of Rtg1/3, two basic helix-loop-helix leucine zipper transcription factors. Rtg1/3 activation requires Rtg2, a cytoplasmic protein with an N-terminal adenosine triphosphate (ATP binding domain belonging to the actin/Hsp70/sugar kinase superfamily. The critical regulatory step of the retrograde response is the interaction between Rtg2 and Mks1. Rtg2 binds to and inactivates Mks1, allowing for activation of Rtg1/3 and the RTG pathway. When the pathway is inactive, Mks1 has dissociated from Rtg2 and bound to Bmh1/2, preventing activation of Rtg1/3. What signals association or disassociation of Mks1 and Rtg2 is unknown. Here, we show that ATP at physiological concentrations dissociates Mks1 from Rtg2 in a highly cooperative fashion. We report that ATP-mediated dissociation of Mks1 from Rtg2 is conserved in two other fungal species, K. lactis and K. waltii. Activation of Rtg1/3 upregulates expression of genes encoding enzymes catalyzing the first three reactions of the Krebs cycle, which is coupled to ATP synthesis through oxidative phosphorylation. Therefore, we propose that the retrograde response is an ATP homeostasis pathway coupling ATP production with ATP-mediated repression of the retrograde response by releasing Mks1 from Rtg2.

  4. Cellular and developmental adaptations to hypoxia: a Drosophila perspective.

    Science.gov (United States)

    Romero, Nuria Magdalena; Dekanty, Andrés; Wappner, Pablo

    2007-01-01

    The fruit fly Drosophila melanogaster, a widely utilized genetic model, is highly resistant to oxygen starvation and is beginning to be used for studying physiological, developmental, and cellular adaptations to hypoxia. The Drosophila respiratory (tracheal) system has features in common with the mammalian circulatory system so that an angiogenesis-like response occurs upon exposure of Drosophila larvae to hypoxia. A hypoxia-responsive system homologous to mammalian hypoxia-inducible factor (HIF) has been described in the fruit fly, where Fatiga is a Drosophila oxygen-dependent HIF prolyl hydroxylase, and the basic helix-loop-helix Per/ARNT/Sim (bHLH-PAS) proteins Sima and Tango are, respectively, the Drosophila homologues of mammalian HIF-alpha (alpha) and HIF-beta (beta). Tango is constitutively expressed regardless of oxygen tension and, like in mammalian cells, Sima is controlled at the level of protein degradation and subcellular localization. Sima is critically required for development in hypoxia, but, unlike mammalian model systems, it is dispensable for development in normoxia. In contrast, fatiga mutant alleles are all lethal; however, strikingly, viability to adulthood is restored in fatiga sima double mutants, although these double mutants are not entirely normal, suggesting that Fatiga has Sima-independent functions in fly development. Studies in cell culture and in vivo have revealed that Sima is activated by the insulin receptor (InR) and target-of-rapamycin (TOR) pathways. Paradoxically, Sima is a negative regulator of growth. This suggests that Sima is engaged in a negative feedback loop that limits growth upon stimulation of InR/TOR pathways.

  5. Basic leucine zipper protein Cnc-C is a substrate and transcriptional regulator of the Drosophila 26S proteasome.

    Science.gov (United States)

    Grimberg, Kristian Björk; Beskow, Anne; Lundin, Daniel; Davis, Monica M; Young, Patrick

    2011-02-01

    While the 26S proteasome is a key proteolytic complex, little is known about how proteasome levels are maintained in higher eukaryotic cells. Here we describe an RNA interference (RNAi) screen of Drosophila melanogaster that was used to identify transcription factors that may play a role in maintaining levels of the 26S proteasome. We used an RNAi library against 993 Drosophila transcription factor genes to identify genes whose suppression in Schneider 2 cells stabilized a ubiquitin-green fluorescent protein reporter protein. This screen identified Cnc (cap 'n' collar [CNC]; basic region leucine zipper) as a candidate transcriptional regulator of proteasome component expression. In fact, 20S proteasome activity was reduced in cells depleted of cnc. Immunoblot assays against proteasome components revealed a general decline in both 19S regulatory complex and 20S proteasome subunits after RNAi depletion of this transcription factor. Transcript-specific silencing revealed that the longest of the seven transcripts for the cnc gene, cnc-C, was needed for proteasome and p97 ATPase production. Quantitative reverse transcription-PCR confirmed the role of Cnc-C in activation of transcription of genes encoding proteasome components. Expression of a V5-His-tagged form of Cnc-C revealed that the transcription factor is itself a proteasome substrate that is stabilized when the proteasome is inhibited. We propose that this single cnc gene in Drosophila resembles the ancestral gene family of mammalian nuclear factor erythroid-derived 2-related transcription factors, which are essential in regulating oxidative stress and proteolysis.

  6. Diffusion tensor imaging measures of white matter compared to myelin basic protein immunofluorescence in tissue cleared intact brains

    Directory of Open Access Journals (Sweden)

    Eric H. Chang

    2017-02-01

    Full Text Available We provide datasets from combined ex vivo diffusion tensor imaging (DTI and Clear Lipid-exchanged, Anatomically Rigid, Imaging/immunostaining compatible, Tissue hYdrogel (CLARITY performed on intact mouse brains. DTI-derived measures of fractional anisotropy (FA, radial diffusivity (RD, and axial diffusivity (AD were compared to antibody-based labeling of myelin basic protein (MBP, as measured by fluorescence microscopy. We used a customized CLARITY hydrogel solution to facilitate whole brain tissue clearing and subsequent immunolabeling. We describe how CLARITY was made compatible with magnetic resonance imaging with the intention of facilitating future multimodal imaging studies that may combine noninvasive imaging with 3D immunohistochemistry. These data and methods are related to the accompanying research article entitled, ‘The role of myelination in measures of white matter integrity: Combination of diffusion tensor imaging and two-photon microscopy of CLARITY intact brains’ (E.H. Chang, M. Argyelan, M. Aggarwal, T-S. Chandon, K.H. Karlsgodt, S. Mori, A.K. Malhotra, 2016 [1].

  7. Protamine-like sperm nuclear basic proteins in the primitive frog Ascaphus truei and histone reversions among more advanced frogs.

    Science.gov (United States)

    Kasinsky, H E; Gutovich, L; Kulak, D; Mackay, M; Green, D M; Hunt, J; Ausio, J

    1999-12-01

    Sperm nuclear basic proteins (SNBPs) that condense chromatin are very diverse. In animals, evolution of SNBPs has proceeded from lysine-rich histone H type in sponges to more arginine-rich protamine-like PL and protamine P types. Yet sporadic PL/P to H reversions are known to occur in both protostomes and deuterostomes. To determine why this is the case, we have examined SNBPs in eleven anuran species. We find that sperm of the primitive, internally fertilizing archeobatrachian frog A. truei (family Ascaphidae) has PL/P type (42 mol % arginine), with an electrophoretic profile similar to SNBPs in another archeobatrachian, externally fertilizing Leiopelma hochstetteri (family Leiopelmatidae). Cytochemistry of sperm nuclei in the advanced, externally fertilizing neobatrachian frogs Crinia signifera and C. deserticola (family Myobatrachidae) indicates that they have reverted to H type SNBPs. This is also known to be the case in externally fertilizing Rana (family Ranidae) and Silurana, a subgenus of Xenopus (family Pipidae). Such a trend, from PL/P type SNBPs in two archeobatrachians to sporadic reversions to H type in more advanced frogs, parallels the ultrastructural simplification from complex A. truei introsperm to neobatrachian aquasperm that Jamieson et al. (1993. Herpetologica 49:52-65) attribute as a secondary reversion to external fertilization.

  8. Catalytic activity of autoantibodies toward myelin basic protein correlates with the scores on the multiple sclerosis expanded disability status scale.

    Science.gov (United States)

    Ponomarenko, Natalia A; Durova, Oxana M; Vorobiev, Ivan I; Belogurov, Alexey A; Telegin, Georgy B; Suchkov, Sergey V; Misikov, Victor K; Morse, Herbert C; Gabibov, Alexander G

    2006-02-28

    Autoantibodies toward myelin basic protein (MBP) evidently emerge in sera and cerebrospinal fluid of the patients with multiple sclerosis (MS), as well as in a MS rodent model, i.e., experimental autoimmune encephalomyelitis (EAE). The studies of the last two decades have unveiled somewhat controversial data on the diagnostic applicability of anti-MBP autoantibodies as a disease' marker. Here, we present the results of new functional analysis of the anti-MBP autoantibodies isolated from MS (in patients) and EAE (in mice) sera, based on their proteolytic activity against the targeted autoantigen. The activity was shown to be the intrinsic property of the IgG molecule. No activity was found in the sera-derived antibody fraction of healthy donors and control mice. Sera of 24 patients with clinically proven MS at different stages of the disease, and 20 healthy controls were screened for the anti-MBP antibody-mediated proteolytic activity. The activity correlated with the scores on the MS expanded disability status scale (EDSS) (r(2)=0.85, P<0.001). Thus, the anti-MBP autoantibody-mediated proteolysis may be regarded as an additional marker of the disease progression.

  9. [Relationship between anti-myelin basic protein antibody and myelinoclasis in rat brain stem after brain trauma].

    Science.gov (United States)

    Li, Wei; Chen, Shan-Cheng; Wang, Zhi-Gang; Song, Xiu-Bao; Wang, Yu-Ping; Zhang, Mei

    2008-06-01

    To investigate the relations between anti-myelin basic protein antibody (anti-MBP) variation and myelinoclasis in the brain stem following brain trauma. In rat models of brain trauma, MBP content and anti-MBP titer in the blood were measured using enzyme-linked immunosorbent assay (ELISA) at different time points after brain trauma, and the degree of myelinoclasis in the brain stem slices was assessed with osmic acid staining. Early after brain trauma, MBP content in the blood increased followed by significant reduction 10 days later. Four days after the trauma, anti-MBP titer was markedly increased, accompanied by obvious exacerbation of myelinoclasis in the brain stem, both reaching the highest levels on day 10, at the point of which anti-MBP titer increased by 4 folds and the number of myelinoclasis by 10 folds compared with the control group. Anti-MBP titer and brain stem myelinolysis both lowered 30 days later. Correlation analysis showed an intimate positive correlation between anti-MBP titer and the degree of myelinoclasis. After brain trauma, MBP is released as a specific antigen into the blood to stimulate the immune system for anti-MBP production, and the antibody is intimately related to the brain stem myelinoclasis.

  10. Adsorption mechanism of myelin basic protein on model substrates and its bridging interaction between the two surfaces.

    Science.gov (United States)

    Lee, Dong Woog; Banquy, Xavier; Kristiansen, Kai; Min, Younjin; Ramachandran, Arun; Boggs, Joan M; Israelachvili, Jacob N

    2015-03-17

    Myelin basic protein (MBP) is an intrinsically disordered (unstructured) protein known to play an important role in the stability of myelin's multilamellar membrane structure in the central nervous system. The adsorption of MBP and its capacity to interact with and bridge solid substrates has been studied using a surface forces apparatus (SFA) and a quartz crystal microbalance with dissipation (QCM-D). Adsorption experiments show that MBP molecules adsorb to the surfaces in a swollen state before undergoing a conformational change into a more compact structure with a thickness of ∼3 nm. Moreover, this compact structure is able to interact with nearby mica surfaces to form adhesive bridges. The measured adhesion force (energy) between two bridged surfaces is 1.0 ± 0.1 mN/m, (Ead = 0.21 ± 0.02 mJ/m(2)), which is slightly smaller than our previously reported adhesion force of 1.7 mN/m (Ead = 0.36 mJ/m(2)) for MBP adsorbed on two supported lipid bilayers (Lee et al., Proc. Natl. Acad. Sci. U.S.A. 2014, 111, E768-E775). The saturated surface concentration of compact MBP on a single SiO2 surface reaches a stable value of 310 ± 10 ng/cm(2) regardless of the bulk MBP concentration. A kinetic three-step adsorption model was developed that accurately fits the adsorption data. The developed model is a general model, not limited to intrinsically disordered proteins, that can be extended to the adsorption of various chemical compounds that undergo chemical reactions and/or conformational changes upon adsorbing to surfaces. Taken together with our previously published data (Lee et al., Proc. Natl. Acad. Sci. U.S.A. 2014, 111, E768-E775), the present results confirm that conformational changes of MBP upon adsorption are a key for strong adhesion, and that such conformational changes are strongly dependent on the nature of the surfaces.

  11. Nucleolar targeting of proteins by the tandem array of basic amino acid stretches identified in the RNA polymerase I-associated factor PAF49

    International Nuclear Information System (INIS)

    Ushijima, Ryujiro; Matsuyama, Toshifumi; Nagata, Izumi; Yamamoto, Kazuo

    2008-01-01

    There is accumulating evidence to indicate that the regulation of subnuclear compartmentalization plays important roles in cellular processes. The RNA polymerase I-associated factor PAF49 has been shown to accumulate in the nucleolus in growing cells, but disperse into the nucleoplasm in growth-arrested cells. Serial deletion analysis revealed that amino acids 199-338 were necessary for the nucleolar localization of PAF49. Combinatorial point mutation analysis indicated that the individual basic amino acid stretches (BS) within the central (BS1-4) and the C-terminal (BS5 and 6) regions may cooperatively confer the nucleolar localization of PAF49. Addition of the basic stretches in tandem to a heterologous protein, such as the interferon regulatory factor-3, translocated the tagged protein into the nucleolus, even in the presence of an intrinsic nuclear export sequence. Thus, tandem array of the basic amino acid stretches identified here functions as a dominant nucleolar targeting sequence

  12. Endogenous interferon-β-inducible gene expression and interferon-β-treatment are associated with reduced T cell responses to myelin basic protein in multiple sclerosis

    DEFF Research Database (Denmark)

    Börnsen, Lars; Christensen, Jeppe Romme; Ratzer, Rikke

    2015-01-01

    patients with an increased expression of interferon-β-inducible genes in peripheral blood mononuclear cells and interferon-β-treated multiple sclerosis patients had decreased CD4+ T-cell reactivity to the autoantigen myelin basic protein ex vivo. Interferon-β-treated multiple sclerosis patients had...... increased IL10 and IL27 gene expression levels in monocytes in vivo. In vitro, neutralization of interleukin-10 and monocyte depletion increased CD4+ T-cell reactivity to myelin basic protein while interleukin-10, in the presence or absence of monocytes, inhibited CD4+ T-cell reactivity to myelin basic......Autoreactive CD4+ T-cells are considered to play a major role in the pathogenesis of multiple sclerosis. In experimental autoimmune encephalomyelitis, an animal model of multiple sclerosis, exogenous and endogenous type I interferons restrict disease severity. Recombinant interferon-β is used...

  13. Peripheral nerve P2 basic protein and the Guillain-Barre syndrome : In vitro demonstration of P2-specific antibody-secreting cells

    NARCIS (Netherlands)

    Luijten, J.A.F.M.; Jong, W.A.C. de; Demel, R.A.; Heijnen, C.J.; Ballieux, R.E.

    1984-01-01

    An immune response to the peripheral nerve basic protein P2 may be operative in the pathogenesis of the Guillain-Barré syndrome (GBS). A method is described for the purification of P2 of human origin. Purified P2 was used to investigate whether lymphocytes derived from peripheral blood of GBS

  14. T helper cell type 1 (Th1), Th2 and Th17 responses to myelin basic protein and disease activity in multiple sclerosis

    DEFF Research Database (Denmark)

    Hedegaard, Chris J; Krakauer, Martin; Bendtzen, Klaus

    2008-01-01

    Autoreactive T cells are thought to play an essential role in the pathogenesis of multiple sclerosis (MS). We examined the stimulatory effect of human myelin basic protein (MBP) on mononuclear cell (MNC) cultures from 22 patients with MS and 22 sex-matched and age-matched healthy individuals, and...

  15. ChIP-seq and in vivo transcriptome analyses of the Aspergillus fumigatus SREBP SrbA reveals a new regulator of the fungal hypoxia response and virulence.

    Directory of Open Access Journals (Sweden)

    Dawoon Chung

    2014-11-01

    Full Text Available The Aspergillus fumigatus sterol regulatory element binding protein (SREBP SrbA belongs to the basic Helix-Loop-Helix (bHLH family of transcription factors and is crucial for antifungal drug resistance and virulence. The latter phenotype is especially striking, as loss of SrbA results in complete loss of virulence in murine models of invasive pulmonary aspergillosis (IPA. How fungal SREBPs mediate fungal virulence is unknown, though it has been suggested that lack of growth in hypoxic conditions accounts for the attenuated virulence. To further understand the role of SrbA in fungal infection site pathobiology, chromatin immunoprecipitation followed by massively parallel DNA sequencing (ChIP-seq was used to identify genes under direct SrbA transcriptional regulation in hypoxia. These results confirmed the direct regulation of ergosterol biosynthesis and iron uptake by SrbA in hypoxia and revealed new roles for SrbA in nitrate assimilation and heme biosynthesis. Moreover, functional characterization of an SrbA target gene with sequence similarity to SrbA identified a new transcriptional regulator of the fungal hypoxia response and virulence, SrbB. SrbB co-regulates genes involved in heme biosynthesis and demethylation of C4-sterols with SrbA in hypoxic conditions. However, SrbB also has regulatory functions independent of SrbA including regulation of carbohydrate metabolism. Loss of SrbB markedly attenuates A. fumigatus virulence, and loss of both SREBPs further reduces in vivo fungal growth. These data suggest that both A. fumigatus SREBPs are critical for hypoxia adaptation and virulence and reveal new insights into SREBPs' complex role in infection site adaptation and fungal virulence.

  16. Transcriptomic and hormone analyses reveal mechanisms underlying petal elongation in Chrysanthemum morifolium 'Jinba'.

    Science.gov (United States)

    Wang, Jingjing; Wang, Haibin; Ding, Lian; Song, Aiping; Shen, Feng; Jiang, Jiafu; Chen, Sumei; Chen, Fadi

    2017-04-01

    Auxin regulates chrysanthemum petal elongation by promoting cell elongation. Transcriptomic analysis shows that auxin signal transduction may connect with other transcription factors by TCPs to regulate chrysanthemum petal elongation. As an ornamental species, Chrysanthemum morifolium has high ornamental and economic value. Petal size is the primary factor that influences the ornamental value of chrysanthemum, but the mechanism underlying the development of C. morifolium petals remains unclear. In our study, we tracked the growth of petals and found that the basal region of 'Jinba' petals showed a higher elongation rate, exhibiting rapid cell elongation during petal growth. During petal elongation growth, auxin was demonstrated to promote cell elongation and an increase in cell numbers in the petal basal region. To further study the molecular mechanisms underlying petal growth, the RNA-seq (high-throughput cDNA sequencing) technique was employed. Four cDNA libraries were assembled from petals in the budding, bud breaking, early blooming and full blooming stages of 'Jinba' flower development. Analysis of differentially expressed genes (DEGs) showed that auxin was the most important regulator in controlling petal growth. The TEOSINTEBRANCHED 1, CYCLOIDEA and PCF transcription factor genes (TCPs), basic helix-loop-helix-encoding gene (bHLH), glutaredoxin-C (GRXC) and other zinc finger protein genes exhibited obvious up-regulation and might have significant effects on the growth of 'Jinba' petals. Given the interaction between these genes in Arabidopsis thaliana, we speculated that auxin signal transduction might exhibit a close relationship with transcription factors through TCPs. In summary, we present the first comprehensive transcriptomic and hormone analyses of C. morifolium petals. The results offer direction in identifying the mechanism underlying the development of chrysanthemum petals in the elongated phase and have great significance in improving the

  17. RSL Class I Genes Controlled the Development of Epidermal Structures in the Common Ancestor of Land Plants.

    Science.gov (United States)

    Proust, Hélène; Honkanen, Suvi; Jones, Victor A S; Morieri, Giulia; Prescott, Helen; Kelly, Steve; Ishizaki, Kimitsune; Kohchi, Takayuki; Dolan, Liam

    2016-01-11

    The colonization of the land by plants, sometime before 470 million years ago, was accompanied by the evolution tissue systems [1-3]. Specialized structures with diverse functions-from nutrient acquisition to reproduction-derived from single cells in the outermost layer (epidermis) were important sources of morphological innovation at this time [2, 4, 5]. In extant plants, these structures may be unicellular extensions, such as root hairs or rhizoids [6-9], or multicellular structures, such as asexual propagules or secretory hairs (papillae) [10-12]. Here, we show that a ROOTHAIR DEFECTIVE SIX-LIKE (RSL) class I basic helix-loop-helix transcription factor positively regulates the development of the unicellular and multicellular structures that develop from individual cells that expand out of the epidermal plane of the liverwort Marchantia polymorpha; mutants that lack MpRSL1 function do not develop rhizoids, slime papillae, mucilage papillae, or gemmae. Furthermore, we discovered that RSL class I genes are also required for the development of multicellular axillary hairs on the gametophyte of the moss Physcomitrella patens. Because class I RSL proteins also control the development of rhizoids in mosses and root hairs in angiosperms [13, 14], these data demonstrate that the function of RSL class I genes was to control the development of structures derived from single epidermal cells in the common ancestor of the land plants. Class I RSL genes therefore controlled the generation of adaptive morphological diversity as plants colonized the land from the water. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  18. Arabidopsis AtbHLH112 regulates the expression of genes involved in abiotic stress tolerance by binding to their E-box and GCG-box motifs.

    Science.gov (United States)

    Liu, Yujia; Ji, Xiaoyu; Nie, Xianguang; Qu, Min; Zheng, Lei; Tan, Zilong; Zhao, Huimin; Huo, Lin; Liu, Shengnan; Zhang, Bing; Wang, Yucheng

    2015-08-01

    Plant basic helix-loop-helix (bHLH) transcription factors play essential roles in abiotic stress tolerance. However, most bHLHs have not been functionally characterized. Here, we characterized the functional role of a bHLH transcription factor from Arabidopsis, AtbHLH112, in response to abiotic stress. AtbHLH112 is a nuclear-localized protein, and its nuclear localization is induced by salt, drought and abscisic acid (ABA). In addition, AtbHLH112 serves as a transcriptional activator, with the activation domain located at its N-terminus. In addition to binding to the E-box motifs of stress-responsive genes, AtbHLH112 binds to a novel motif with the sequence 'GG[GT]CC[GT][GA][TA]C' (GCG-box). Gain- and loss-of-function analyses showed that the transcript level of AtbHLH112 is positively correlated with salt and drought tolerance. AtbHLH112 mediates stress tolerance by increasing the expression of P5CS genes and reducing the expression of P5CDH and ProDH genes to increase proline levels. AtbHLH112 also increases the expression of POD and SOD genes to improve reactive oxygen species (ROS) scavenging ability. We present a model suggesting that AtbHLH112 is a transcriptional activator that regulates the expression of genes via binding to their GCG- or E-boxes to mediate physiological responses, including proline biosynthesis and ROS scavenging pathways, to enhance stress tolerance. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

  19. Differential gene expression and mitotic cell analysis of the drought tolerant soybean (Glycine max L. Merrill Fabales, Fabaceae cultivar MG/BR46 (Conquista under two water deficit induction systems

    Directory of Open Access Journals (Sweden)

    Polyana K. Martins

    2008-01-01

    Full Text Available Drought cause serious yield losses in soybean (Glycine max, roots being the first plant organ to detect the water-stress signals triggering defense mechanisms. We used two drought induction systems to identify genes differentially expressed in the roots of the drought-tolerant soybean cultivar MG/BR46 (Conquista and characterize their expression levels during water deficit. Soybean plants grown in nutrient solution hydroponically and in sand-pots were submitted to water stress and gene expression analysis was conducted using the differential display (DD and real time polymerase chain reaction (PCR techniques. Three differentially expressed mRNA transcripts showed homology to the Antirrhinum majus basic helix-loop-helix transcription factor bHLH, the Arabidopsis thaliana phosphatidylinositol transfer protein PITP and the auxin-independent growth regulator 1 (axi 1. The hydroponic experiments showed that after 100 min outside the nutrient solution photosynthesis completely stopped, stomata closed and leaf temperature rose. Both stress induction treatments produced significant decrease in the mitotic indices of root cells. Axi 1, PITP and bHLH were not only differentially expressed during dehydration in the hydroponics experiments but also during induced drought in the pot experiments. Although, there were differences between the two sets of experiments in the time at which up or down regulation occurred, the expression pattern of all three transcripts was related. Similar gene expression and cytological analysis results occurred in both systems, suggesting that hydroponics could be used to simulate drought detection by roots growing in soil and thus facilitate rapid and easy root sampling.

  20. Hand1 overexpression inhibits medulloblastoma metastasis

    Energy Technology Data Exchange (ETDEWEB)

    Asuthkar, Swapna; Guda, Maheedhara R. [Department of Cancer Biology and Pharmacology, University of Illinois College of Medicine at Peoria, Peoria, IL 61656 (United States); Martin, Sarah E. [Department of Pathology, University of Illinois College of Medicine at Peoria, Peoria, IL 61656 (United States); Antony, Reuben; Fernandez, Karen [Department of Pediatrics, University of Illinois College of Medicine at Peoria, Peoria, IL 61656 (United States); Lin, Julian [Department of Neurosurgery, University of Illinois College of Medicine at Peoria, Peoria, IL 61656 (United States); Tsung, Andrew J. [Department of Cancer Biology and Pharmacology, University of Illinois College of Medicine at Peoria, Peoria, IL 61656 (United States); Department of Neurosurgery, University of Illinois College of Medicine at Peoria, Peoria, IL 61656 (United States); Illinois Neurological Institute, Peoria, IL 61656 (United States); Velpula, Kiran K., E-mail: velpula@uic.edu [Department of Cancer Biology and Pharmacology, University of Illinois College of Medicine at Peoria, Peoria, IL 61656 (United States); Department of Neurosurgery, University of Illinois College of Medicine at Peoria, Peoria, IL 61656 (United States)

    2016-08-19

    Medulloblastoma (MB) is the most frequent malignant pediatric brain tumor. Current treatment includes surgery, radiation and chemotherapy. However, ongoing treatment in patients is further classified according to the presence or absence of metastasis. Since metastatic medulloblastoma are refractory to current treatments, there is need to identify novel biomarkers that could be used to reduce metastatic potential, and more importantly be targeted therapeutically. Previously, we showed that ionizing radiation-induced uPAR overexpression is associated with increased accumulation of β-catenin in the nucleus. We further demonstrated that uPAR protein act as cytoplasmic sequestration factor for a novel basic helix-loop-helix transcription factor, Hand1. Among the histological subtypes classical and desmoplastic subtypes account for the majority while large cell/anaplastic variant is most commonly associated with metastatic disease. In this present study using immunohistochemical approach and patient data mining for the first time, we demonstrated that Hand1 expression is observed to be downregulated in all the subtypes of medulloblastoma. Previously we showed that Hand1 overexpression regulated medulloblastoma angiogenesis and here we investigated the role of Hand1 in the context of Epithelial-Mesenchymal Transition (EMT). Moreover, UW228 and D283 cells overexpressing Hand1 demonstrated decreased-expression of mesenchymal markers (N-cadherin, β-catenin and SOX2); metastatic marker (SMA); and increased expression of epithelial marker (E-cadherin). Strikingly, human pluripotent stem cell antibody array showed that Hand1 overexpression resulted in substantial decrease in pluripotency markers (Nanog, Oct3/4, Otx2, Flk1) suggesting that Hand1 expression may be essential to attenuate the EMT and our findings underscore a novel role for Hand1 in medulloblastoma metastasis. - Highlights: • Hand1 expression is downregulated in Medulloblastoma. • Hand1 over expression reduce

  1. Blue Light–Dependent Interaction between Cryptochrome2 and CIB1 Regulates Transcription and Leaf Senescence in Soybean[W

    Science.gov (United States)

    Meng, Yingying; Li, Hongyu; Wang, Qin; Liu, Bin; Lin, Chentao

    2013-01-01

    Cryptochromes are blue light receptors that regulate light responses in plants, including various crops. The molecular mechanism of plant cryptochromes has been extensively investigated in Arabidopsis thaliana, but it has not been reported in any crop species. Here, we report a study of the mechanism of soybean (Glycine max) cryptochrome2 (CRY2a). We found that CRY2a regulates leaf senescence, which is a life history trait regulated by light and photoperiods via previously unknown mechanisms. We show that CRY2a undergoes blue light–dependent interaction with the soybean basic helix-loop-helix transcription activator CIB1 (for cryptochrome-interacting bHLH1) that specifically interacts with the E-box (CANNTG) DNA sequences. Analyses of transgenic soybean plants expressing an elevated or reduced level of the CRY2a or CIB1 demonstrate that CIB1 promotes leaf senescence, whereas CRY2a suppresses leaf senescence. Results of the gene expression and molecular interaction analyses support the hypothesis that CIB1 activates transcription of senescence-associated genes, such as WRKY DNA BINDING PROTEIN53b (WRKY53b), and leaf senescence. CIB1 interacts with the E-box–containing promoter sequences of the WRKY53b chromatin, whereas photoexcited CRY2a interacts with CIB1 to inhibit its DNA binding activity. These findings argue that CIB-dependent transcriptional regulation is an evolutionarily conserved CRY-signaling mechanism in plants, and this mechanism is opted in evolution to mediate light regulation of different aspects of plant development in different plant species. PMID:24272488

  2. A novel bHLH transcription factor PebHLH35 from Populus euphratica confers drought tolerance through regulating stomatal development, photosynthesis and growth in Arabidopsis

    International Nuclear Information System (INIS)

    Dong, Yan; Wang, Congpeng; Han, Xiao; Tang, Sha; Liu, Sha; Xia, Xinli; Yin, Weilun

    2014-01-01

    Highlights: • PebHLH35 is firstly cloned from Populus euphratica and characterized its functions. • PebHLH35 is important for earlier seedling establishment and vegetative growth. • PebHLH35 enhances tolerance to drought by regulating growth. • PebHLH35 enhances tolerance to drought by regulating stomatal development. • PebHLH35 enhances tolerance to drought by regulating photosynthesis and transpiration. - Abstract: Plant basic helix-loop-helix (bHLH) transcription factors (TFs) are involved in a variety of physiological processes including the regulation of plant responses to various abiotic stresses. However, few drought-responsive bHLH family members in Populus have been reported. In this study, a novel bHLH gene (PebHLH35) was cloned from Populus euphratica. Expression analysis in P. euphratica revealed that PebHLH35 was induced by drought and abscisic acid. Subcellular localization studies using a PebHLH35-GFP fusion showed that the protein was localized to the nucleus. Ectopic overexpression of PebHLH35 in Arabidopsis resulted in a longer primary root, more leaves, and a greater leaf area under well-watered conditions compared with vector control plants. Notably, PebHLH35 overexpression lines showed enhanced tolerance to water-deficit stress. This finding was supported by anatomical and physiological analyses, which revealed a reduced stomatal density, stomatal aperture, transpiration rate, and water loss, and a higher chlorophyll content and photosynthetic rate. Our results suggest that PebHLH35 functions as a positive regulator of drought stress responses by regulating stomatal density, stomatal aperture, photosynthesis and growth

  3. OVO homologue-like 1 (Ovol1) transcription factor: a novel target of neurogenin-3 in rodent pancreas.

    Science.gov (United States)

    Vetere, A; Li, W-C; Paroni, F; Juhl, K; Guo, L; Nishimura, W; Dai, X; Bonner-Weir, S; Sharma, A

    2010-01-01

    The basic helix-loop-helix transcription factor neurogenin-3 (NGN3) commits the fates of pancreatic progenitors to endocrine cell types, but knowledge of the mechanisms regulating the choice between proliferation and differentiation of these progenitors is limited. Using a chromatin immunoprecipitation cloning approach, we searched for direct targets of NGN3 and identified a zinc-finger transcription factor, OVO homologue-like 1 (OVOL1). Transactivation experiments were carried out to elucidate the functional role of NGN3 in Ovol1 gene expression. Embryonic and adult rodents pancreases were immunostained for OVOL1, Ki67 and NGN3. We showed that NGN3 negatively regulates transcription of Ovol1 in an E-box-dependent fashion. The presence of either NGN3 or NEUROD1, but not MYOD, reduced endogenous Ovol1 mRNA. OVOL1 was detected in pancreatic tissue around embryonic day 15.5, after which OVOL1 levels dramatically increased. In embryonic pancreas, OVOL1 protein levels were low in NGN3(+) or Ki67(+) cells, but high in quiescent differentiated cells. OVOL1 presence was maintained in adult pancreas, where it was detected in islets, pancreatic ducts and some acinar cells. Additionally OVOL1 presence was lacking in proliferating ductules in regenerating pancreas and induced in cells as they began to acquire their differentiated phenotype. The timing of OVOL1 appearance in pancreas and its increased levels in differentiated cells suggest that OVOL1 promotes the transition of cells from a proliferating, less-differentiated state to a quiescent more-differentiated state. We conclude that OVOL1, a downstream target of NGN3, may play an important role in regulating the balance between proliferation and differentiation of pancreatic cells.

  4. Hand1 overexpression inhibits medulloblastoma metastasis

    International Nuclear Information System (INIS)

    Asuthkar, Swapna; Guda, Maheedhara R.; Martin, Sarah E.; Antony, Reuben; Fernandez, Karen; Lin, Julian; Tsung, Andrew J.; Velpula, Kiran K.

    2016-01-01

    Medulloblastoma (MB) is the most frequent malignant pediatric brain tumor. Current treatment includes surgery, radiation and chemotherapy. However, ongoing treatment in patients is further classified according to the presence or absence of metastasis. Since metastatic medulloblastoma are refractory to current treatments, there is need to identify novel biomarkers that could be used to reduce metastatic potential, and more importantly be targeted therapeutically. Previously, we showed that ionizing radiation-induced uPAR overexpression is associated with increased accumulation of β-catenin in the nucleus. We further demonstrated that uPAR protein act as cytoplasmic sequestration factor for a novel basic helix-loop-helix transcription factor, Hand1. Among the histological subtypes classical and desmoplastic subtypes account for the majority while large cell/anaplastic variant is most commonly associated with metastatic disease. In this present study using immunohistochemical approach and patient data mining for the first time, we demonstrated that Hand1 expression is observed to be downregulated in all the subtypes of medulloblastoma. Previously we showed that Hand1 overexpression regulated medulloblastoma angiogenesis and here we investigated the role of Hand1 in the context of Epithelial-Mesenchymal Transition (EMT). Moreover, UW228 and D283 cells overexpressing Hand1 demonstrated decreased-expression of mesenchymal markers (N-cadherin, β-catenin and SOX2); metastatic marker (SMA); and increased expression of epithelial marker (E-cadherin). Strikingly, human pluripotent stem cell antibody array showed that Hand1 overexpression resulted in substantial decrease in pluripotency markers (Nanog, Oct3/4, Otx2, Flk1) suggesting that Hand1 expression may be essential to attenuate the EMT and our findings underscore a novel role for Hand1 in medulloblastoma metastasis. - Highlights: • Hand1 expression is downregulated in Medulloblastoma. • Hand1 over expression reduce

  5. A novel bHLH transcription factor PebHLH35 from Populus euphratica confers drought tolerance through regulating stomatal development, photosynthesis and growth in Arabidopsis

    Energy Technology Data Exchange (ETDEWEB)

    Dong, Yan [College of Biological Sciences and Technology, National Engineering Laboratory for Tree Breeding, Beijing Forestry University, Beijing 100083 (China); Liaoning Forestry Vocational-Technical College, Shenyang 110101 (China); Wang, Congpeng; Han, Xiao; Tang, Sha; Liu, Sha [College of Biological Sciences and Technology, National Engineering Laboratory for Tree Breeding, Beijing Forestry University, Beijing 100083 (China); Xia, Xinli, E-mail: xiaxl@bjfu.edu.cn [College of Biological Sciences and Technology, National Engineering Laboratory for Tree Breeding, Beijing Forestry University, Beijing 100083 (China); Yin, Weilun, E-mail: yinwl@bjfu.edu.cn [College of Biological Sciences and Technology, National Engineering Laboratory for Tree Breeding, Beijing Forestry University, Beijing 100083 (China)

    2014-07-18

    Highlights: • PebHLH35 is firstly cloned from Populus euphratica and characterized its functions. • PebHLH35 is important for earlier seedling establishment and vegetative growth. • PebHLH35 enhances tolerance to drought by regulating growth. • PebHLH35 enhances tolerance to drought by regulating stomatal development. • PebHLH35 enhances tolerance to drought by regulating photosynthesis and transpiration. - Abstract: Plant basic helix-loop-helix (bHLH) transcription factors (TFs) are involved in a variety of physiological processes including the regulation of plant responses to various abiotic stresses. However, few drought-responsive bHLH family members in Populus have been reported. In this study, a novel bHLH gene (PebHLH35) was cloned from Populus euphratica. Expression analysis in P. euphratica revealed that PebHLH35 was induced by drought and abscisic acid. Subcellular localization studies using a PebHLH35-GFP fusion showed that the protein was localized to the nucleus. Ectopic overexpression of PebHLH35 in Arabidopsis resulted in a longer primary root, more leaves, and a greater leaf area under well-watered conditions compared with vector control plants. Notably, PebHLH35 overexpression lines showed enhanced tolerance to water-deficit stress. This finding was supported by anatomical and physiological analyses, which revealed a reduced stomatal density, stomatal aperture, transpiration rate, and water loss, and a higher chlorophyll content and photosynthetic rate. Our results suggest that PebHLH35 functions as a positive regulator of drought stress responses by regulating stomatal density, stomatal aperture, photosynthesis and growth.

  6. miR-151-3p Targets TWIST1 to Repress Migration of Human Breast Cancer Cells.

    Directory of Open Access Journals (Sweden)

    Ting-Chih Yeh

    Full Text Available TWIST1 is a highly conserved basic helix-loop-helix transcription factor that contributes to cancer metastasis by promoting an epithelial-mesenchymal transition and repressing E-cadherin gene expression in breast cancer. In this study, we explored the potential role of miR-151 in TWIST1 expression and cancer properties in human breast cancer cells. We found that the human TWIST1 3'UTR contains a potential binging site for miR-151-3p at the putative target sequence 5'-CAGUCUAG-3'. Using a TWIST1-3'UTR luciferase reporter assay, we demonstrated that the target sequence within the TWIST1 3'UTR is required for miR-151-3p regulation of TWIST1 expression. Moreover, we found that ectopic expression of miR-151-3p by infection with adenoviruses expressing miR-151 significantly decreased TWIST1 expression, migration and invasion, but did not affect cell growth and tumorsphere formation of human breast cancer cells. In addition, overexpression of the protein coding region without the 3'UTR of TWIST1 reversed the repression of cell migration by miR-151-3p. Furthermore, knockdown of miR-151-3p increased TWIST1 expression, reduced E-cadherin expression, and enhanced cell migration. In conclusion, these results suggest that miR-151-3p directly regulates TWIST1 expression by targeting the TWIST1 3'UTR and thus repressing the migration and invasion of human breast cancer cells by enhancing E-cadherin expression. Our findings add to accumulating evidence that microRNAs are involved in breast cancer progression by modulating TWIST1 expression.

  7. Smad mediated regulation of inhibitor of DNA binding 2 and its role in phenotypic maintenance of human renal proximal tubule epithelial cells.

    Directory of Open Access Journals (Sweden)

    Mangalakumar Veerasamy

    Full Text Available The basic-Helix-Loop-Helix family (bHLH of transcriptional factors plays a major role in regulating cellular proliferation, differentiation and phenotype maintenance. The downregulation of one of the members of bHLH family protein, inhibitor of DNA binding 2 (Id2 has been shown to induce de-differentiation of epithelial cells. Opposing regulators of epithelial/mesenchymal phenotype in renal proximal tubule epithelial cells (PTEC, TGFβ1 and BMP7 also have counter-regulatory effects in models of renal fibrosis. We investigated the regulation of Id2 by these growth factors in human PTECs and its implication in the expression of markers of epithelial versus myofibroblastic phenotype. Cellular Id2 levels were reduced by TGFβ1 treatment; this was prevented by co-incubation with BMP7. BMP7 alone increased cellular levels of Id2. TGFβ1 and BMP7 regulated Id2 through Smad2/3 and Smad1/5 dependent mechanisms respectively. TGFβ1 mediated Id2 suppression was essential for α-SMA induction in PTECs. Although Id2 over-expression prevented α-SMA induction, it did not prevent E-cadherin loss under the influence of TGFβ1. This suggests that the loss of gate keeper function of E-cadherin alone may not necessarily result in complete EMT and further transcriptional re-programming is essential to attain mesenchymal phenotype. Although BMP7 abolished TGFβ1 mediated α-SMA expression by restoring Id2 levels, the loss of Id2 was not sufficient to induce α-SMA expression even in the context of reduced E-cadherin expression. Hence, a reduction in Id2 is critical for TGFβ1-induced α-SMA expression in this model of human PTECs but is not sufficient in it self to induce α-SMA even in the context of reduced E-cadherin.

  8. Biochemical and molecular analysis of pink tomatoes: deregulated expression of the gene encoding transcription factor SlMYB12 leads to pink tomato fruit color.

    Science.gov (United States)

    Ballester, Ana-Rosa; Molthoff, Jos; de Vos, Ric; Hekkert, Bas te Lintel; Orzaez, Diego; Fernández-Moreno, Josefina-Patricia; Tripodi, Pasquale; Grandillo, Silvana; Martin, Cathie; Heldens, Jos; Ykema, Marieke; Granell, Antonio; Bovy, Arnaud

    2010-01-01

    The color of tomato fruit is mainly determined by carotenoids and flavonoids. Phenotypic analysis of an introgression line (IL) population derived from a cross between Solanum lycopersicum 'Moneyberg' and the wild species Solanum chmielewskii revealed three ILs with a pink fruit color. These lines had a homozygous S. chmielewskii introgression on the short arm of chromosome 1, consistent with the position of the y (yellow) mutation known to result in colorless epidermis, and hence pink-colored fruit, when combined with a red flesh. Metabolic analysis showed that pink fruit lack the ripening-dependent accumulation of the yellow-colored flavonoid naringenin chalcone in the fruit peel, while carotenoid levels are not affected. The expression of all genes encoding biosynthetic enzymes involved in the production of the flavonol rutin from naringenin chalcone was down-regulated in pink fruit, suggesting that the candidate gene underlying the pink phenotype encodes a regulatory protein such as a transcription factor rather than a biosynthetic enzyme. Of 26 MYB and basic helix-loop-helix transcription factors putatively involved in regulating transcription of genes in the phenylpropanoid and/or flavonoid pathway, only the expression level of the MYB12 gene correlated well with the decrease in the expression of structural flavonoid genes in peel samples of pink- and red-fruited genotypes during ripening. Genetic mapping and segregation analysis showed that MYB12 is located on chromosome 1 and segregates perfectly with the characteristic pink fruit color. Virus-induced gene silencing of SlMYB12 resulted in a decrease in the accumulation of naringenin chalcone, a phenotype consistent with the pink-colored tomato fruit of IL1b. In conclusion, biochemical and molecular data, gene mapping, segregation analysis, and virus-induced gene silencing experiments demonstrate that the MYB12 transcription factor plays an important role in regulating the flavonoid pathway in tomato fruit

  9. Protein standardization III: Method optimization basic principles for quantitative determination of human serum proteins on automated instruments based on turbidimetry or nephelometry.

    Science.gov (United States)

    Blirup-Jensen, S

    2001-11-01

    Quantitative protein determinations in routine laboratories are today most often carried out using automated instruments. However, slight variations in the assay principle, in the programming of the instrument or in the reagents may lead to different results. This has led to the prerequisite of method optimization and standardization. The basic principles of turbidimetry and nephelometry are discussed. The different reading principles are illustrated and investigated. Various problems are identified and a suggestion is made for an integrated, fast and convenient test system for the determination of a number of different proteins on the same instrument. An optimized test system for turbidimetry and nephelometry should comprise high-quality antibodies, calibrators, controls, and buffers and a protocol with detailed parameter settings in order to program the instrument correctly. A good user program takes full advantage of the optimal reading principles for the different instruments. This implies--for all suitable instruments--sample preincubation followed by real sample blanking, which automatically corrects for initial turbidity in the sample. Likewise it is recommended to measure the reagent blank, which represents any turbidity caused by the antibody itself. By correcting all signals with these two blank values the best possible signal is obtained for the specific analyte. An optimized test system should preferably offer a wide measuring range combined with a wide security range, which for the user means few re-runs and maximum security against antigen excess. A non-linear calibration curve based on six standards is obtained using a suitable mathematical fitting model, which normally is part of the instrument software.

  10. Gene expression in the spinal cord in female lewis rats with experimental autoimmune encephalomyelitis induced with myelin basic protein.

    Directory of Open Access Journals (Sweden)

    Hayley R Inglis

    Full Text Available BACKGROUND: Experimental autoimmune encephalomyelitis (EAE, the best available model of multiple sclerosis, can be induced in different animal strains using immunization with central nervous system antigens. EAE is associated with inflammation and demyelination of the nervous system. Micro-array can be used to investigate gene expression and biological pathways that are altered during disease. There are few studies of the changes in gene expression in EAE, and these have mostly been done in a chronic mouse EAE model. EAE induced in the Lewis with myelin basic protein (MBP-EAE is well characterised, making it an ideal candidate for the analysis of gene expression in this disease model. METHODOLOGY/PRINCIPAL FINDINGS: MBP-EAE was induced in female Lewis rats by inoculation with MBP and adjuvants. Total RNA was extracted from the spinal cords and used for micro-array analysis using AffimetrixGeneChip Rat Exon 1.0 ST Arrays. Gene expression in the spinal cords was compared between healthy female rats and female rats with MBP-EAE. Gene expression in the spinal cord of rats with MBP-EAE differed from that in the spinal cord of normal rats, and there was regulation of pathways involved with immune function and nervous system function. For selected genes the change in expression was confirmed with real-time PCR. CONCLUSIONS/SIGNIFICANCE: EAE leads to modulation of gene expression in the spinal cord. We have identified the genes that are most significantly regulated in MBP-EAE in the Lewis rat and produced a profile of gene expression in the spinal cord at the peak of disease.

  11. Purification, partial characterization, crystallization and preliminary X-ray diffraction of a novel cardiotoxin-like basic protein from Naja naja atra (South Anhui) venom

    Energy Technology Data Exchange (ETDEWEB)

    Rong, Hui; Li, Yan; Lou, Xiao-hua; Zhang, Xio; Gao, Yong-xiang; Teng, Mai-kun, E-mail: mkteng@ustc.edu.cn; Niu, Li-wen, E-mail: mkteng@ustc.edu.cn [Hefei National Laboratory for Physical Sciences at Microscale and School of Life Sciences, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230027 (China); Key Laboratory of Structural Biology, Chinese Academy of Sciences, 96 Jinzhai Road, Hefei, Anhui 230027 (China)

    2007-02-01

    A novel cardiotoxin-like basic protein from Naja naja atra was crystallized and diffraction data were collected to 2.35 Å resolution. A novel cardiotoxin-like basic protein was isolated from the venom of the Chinese cobra (Naja naja atra) from the south of Anhui in China. The protein inhibits the expression of vascular endothelial growth factor and basic fibroblast growth factor in human lung cancer cell line H1299 and induces the haemolysis of rabbit erythrocytes under low-lecithin conditions. After a two-step chromatographic purification, the resultant 7 kDa protein was crystallized by the hanging-drop vapour-diffusion method at room temperature. A complete data set was collected to 2.35 Å resolution using an in-house X-ray diffraction system. The crystal belongs to space group P4{sub 1}2{sub 1}2, with unit-cell parameters a = b = 43.2, c = 147.9 Å. There are two molecules in the crystallographic asymmetric unit.

  12. In-capillary enrichment, proteolysis and separation using capillary electrophoresis with discontinuous buffers: application on proteins with moderately acidic and basic isoelectric points.

    Science.gov (United States)

    Nesbitt, Chandra A; Yeung, Ken K-C

    2009-01-01

    Advances in mass spectrometry and capillary-format separation continue to improve the sensitivity of protein analysis. Of equal importance is the miniaturization of sample pretreatment such as enrichment and proteolysis. In a previous report (Nesbitt et al., Electrophoresis, 2008, 29, 466-474), nanoliter-volume protein enrichment, tryptic digestion, and partial separation was demonstrated in capillary electrophoresis followed by MALDI mass spectral analysis. A discontinuous buffer system, consisting of ammonium (pH 10) and acetate (pH 4), was used to create a pH junction inside the capillary, trapping a protein with a neutral isoelectric point, myoglobin (pI 7.2). Moreover, co-enrichment of myoglobin with trypsin led to an in-capillary digestion. In this paper, the ability of this discontinuous buffer system to perform similar in-capillary sample pretreatment on proteins with moderately acidic and basic pI was studied and reported. Lentil lectin (pI 8.6) and a multi-phosphorylated protein, beta-casein (pI 5.1), were selected as model proteins. In addition to the previously shown tryptic digestion, proteolysis with endoproteinase Asp-N was also performed. Digestion of these acidic and basic pI proteins produced a few peptides with extreme pI values lying outside the trapping range of the discontinuous buffer. An alteration in the peptide trapping procedure was made to accommodate these analytes. Offline MALDI mass spectral analysis confirmed the presence of the expected peptides. The presented miniaturized sample pretreatment methodology was proven to be applicable on proteins with a moderately wide range of pI. Flexibility in the choice of protease was also evident.

  13. Brain Basics

    Medline Plus

    Full Text Available ... About Us Home > Health & Education > Educational Resources Brain Basics Introduction The Growing Brain The Working Brain Brain ... called the hypothalamic-pituitary-adrenal (HPA) axis. Brain Basics in Real Life Brain Basics in Real Life— ...

  14. Brain Basics

    Medline Plus

    Full Text Available ... Brain Research Glossary Brain Basics (PDF, 10 pages) Introduction Watch the Brain Basics video Welcome. Brain Basics provides information on how the brain works, how mental illnesses ...

  15. Brain Basics

    Medline Plus

    Full Text Available ... at NIMH News & Events About Us Home > Health & Education > Educational Resources Brain Basics Introduction The Growing Brain The Working Brain Brain Basics in Real Life Brain Research Glossary Brain Basics (PDF, 10 pages) Introduction Watch the Brain Basics video ...

  16. Mutations in the basic region of the Mason-Pfizer monkey virus nucleocapsid protein affect reverse transcription, gRNA packaging and the site of viral assembly.

    Science.gov (United States)

    Dostálková, Alžběta; Kaufman, Filip; Křížová, Ivana; Kultová, Anna; Strohalmová, Karolína; Hadravová, Romana; Ruml, Tomáš; Rumlová, Michaela

    2018-02-28

    In addition to specific RNA-binding zinc finger domains, retroviral Gag polyprotein contains clusters of basic amino acid residues thought to support Gag-viral genomic RNA (gRNA) interactions. One of these clusters is the basic K 16 NK 18 EK 20 region, located upstream of the first zinc finger of the Mason-Pfizer monkey virus (M-PMV) nucleocapsid protein (NC). To investigate the role of this basic region in the M-PMV life cycle, we used a combination of in vivo and in vitro methods to study a series of mutants in which the overall charge of this region was more positive (RNRER), more negative (AEAEA), or neutral (AAAAA). The mutations markedly affected gRNA incorporation and the onset of reverse transcription. Introducing a more negative charge (AEAEA) significantly reduced the incorporation of M-PMV gRNA into nascent particles. Moreover, the assembly of immature particles of the AEAEA Gag mutant was relocated from the perinuclear region to the plasma membrane. In contrast, enhancing the basicity of this region of M-PMV NC (RNRER) caused substantially more efficient incorporation of gRNA, subsequently resulting in an increase in M-PMV RNRER infectivity. Nevertheless, despite the higher amount of gRNA packaged by the RNRER mutant, the onset of reverse transcription was delayed in comparison to that of the wild type. Our data clearly show the requirement for certain positively charged amino acid residues upstream of the first zinc finger for proper gRNA incorporation, assembly of immature particles and proceeding of reverse transcription. Importance: We identified a short sequence within Gag polyprotein that, together with the zinc finger domains and previously identified RKK motif, contributes to packaging of genomic RNA (gRNA) of Mason-Pfizer monkey virus (M-PMV). Importantly, in addition to gRNA incorporation this basic region (KNKEK) at the N-terminus of nucleocapsid protein is crucial for an onset of reverse transcription. The mutations changing the positive

  17. Cloning of human basic A1, a distinct 59-kDa dystrophin-associated protein encoded on chromosome 8q23-24

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, A.H. [Harvard Medical School, Boston, MA (United States); Yoshida, Mikiharu; Hagiwara, Yasuko; Ozawa, Eijiro [National Institute of Neuroscience, Ogawa Higashi, Kodaira (Japan); Anderson, M.S.; Feener, C.A.; Selig, S. [Howard Hughes Medical Institute at Children`s Hospital, Boston, MA (United States); Kunkel, L.M. [Harvard Medical School, Boston, MA (United States)]|[Howard Hughes Medical Institute at Children`s Hosptial, Boston, MA (United States)

    1994-05-10

    Duchenne and Becker muscular dystrophies are caused by defects of dystrophin, which forms a part of the membrane cytoskeleton of specialized cells such as muscle. It has been previously shown that the dystrophin-associated protein A1 (59-kDa DAP) is actually a heterogeneous group of phosphorylated proteins consisting of an acidic ({alpha}-A1) and a distinct basic ({beta}-A1) component. Partial peptide sequence of the A1 complex purified from rabbit muscle permitted the design of oligonucleotide probes that were used to isolate a cDNA for one human isoform of A1. This cDNA encodes a basic A1 isoform that is distinct from the recently described syntrophins in Torpedo and mouse and is expressed in many tissues with at least five distinct mRNA species of 5.9, 4.8, 4.3, 3.1, and 1.5 kb. A comparison of the human cDNA sequence with the GenBank expressed sequence tag (EST) data base has identified a relative from human skeletal muscle, EST25263, which is probably a human homologue of the published mouse syntrophin 2. The authors have mapped the human basic component of A1 and EST25263 genes to chromosomes 8q23-24 and 16, respectively.

  18. The effect of beta-interferon therapy on myelin basic protein-elicited CD4+ T cell proliferation and cytokine production in multiple sclerosis

    DEFF Research Database (Denmark)

    Hedegaard, Chris J; Krakauer, Martin; Bendtzen, Klaus

    2008-01-01

    Interferon (IFN)-beta therapy has well-established clinical benefits in multiple sclerosis (MS), but the underlying modulation of cytokine responses to myelin self-antigens remains poorly understood. We analysed the CD4+ T cell proliferation and cytokine responses elicited by myelin basic protein...... (MBP) and a foreign recall antigen, tetanus toxoid (TT), in mononuclear cell cultures from fourteen MS patients undergoing IFN-beta therapy. The MBP-elicited IFN-gamma-, TNF-alpha- and IL-10 production decreased during therapy (p...

  19. Redirecting Therapeutic T Cells against Myelin-Specific T Lymphocytes Using a Humanized Myelin Basic Protein-HLA-DR2-{zeta} Chimeric Receptor

    DEFF Research Database (Denmark)

    Moisini, Ioana; Nguyen, Phuong; Fugger, Lars

    2008-01-01

    to selectively redirect therapeutic T cells against myelin basic protein (MBP)-specific T lymphocytes implicated in MS. We generated two heterodimeric receptors that genetically link the human MBP(84-102) epitope to HLA-DR2 and either incorporate or lack a TCRzeta signaling domain. The Ag-MHC domain serves...... mouse model system. Finally, the chimeric receptor-modified CTL ameliorated or blocked experimental allergic encephalomyelitis (EAE) disease mediated by MBP(84-102)/DR2-specific T lymphocytes. These results provide support for the further development of redirected therapeutic T cells able to counteract...

  20. Myelin basic protein-reactive T cells persist in an inactive state in the bone marrow of Lewis rats that have recovered from autoimmune encephalomyelitis.

    Science.gov (United States)

    Kheradmand, Taba; Wolf, Norbert A; Swanborg, Robert H

    2009-04-30

    Lewis rats immunized with guinea pig myelin basic protein residues 68-86 develop acute experimental autoimmune encephalomyelitis and recover. The predominant T cell receptor expressed by the encephalitogenic T cells is TCRBV8S2. They persist in bone marrow many weeks after recovery. CD3 is down-regulated, but >90% express CD4. They fail to proliferate to GPMBP68-86 unless a nitric oxide synthase inhibitor is added to the cultures. Perhaps these are memory T cells that are maintained in a suppressed state in BM by a nitric oxide-dependent mechanism.

  1. Protection from experimental allergic encephalomyelitis conferred by a monoclonal antibody directed against a shared idiotype on rat T cell receptors specific for myelin basic protein

    OpenAIRE

    1988-01-01

    Immunizing Lewis rats with guinea pig myelin basic protein (MBP) yielded an encephalitogen specific, Ia-restricted, rat-mouse T cell hybridoma 5.10, which was used to establish a clonotypic mAb (10.18) that binds to and precipitates the rat TCR. By two-dimensional gel electrophoresis, the rat TCR was shown to consist of two disulfide- linked peptide chains with mol wt of 48,000 and 39,000. 10.18 binds the majority of cells in MBP-specific T cell lines that are capable of transferring experime...

  2. Myelin Basic Protein-Reactive T Cells Persist in an Inactive State in the Bone Marrow of Lewis Rats that have Recovered from Autoimmune Encephalomyelitis

    OpenAIRE

    Kheradmand, Taba; Wolf, Norbert A.; Swanborg, Robert H.

    2009-01-01

    Lewis rats immunized with guinea pig myelin basic protein residues 68-86 develop acute experimental autoimmune encephalomyelitis and recover. The predominant T cell receptor expressed by the encephalitogenic T cells is TCRBV8S2. They persist in bone marrow many weeks after recovery. CD3 is down-regulated, but > 90% express CD4. They fail to proliferate to GPMBP68-86 unless a nitric oxide synthase inhibitor is added to the cultures. Perhaps these are memory T cells that are maintained in a sup...

  3. Treatment of experimental allergic encephalomyelitis (EAE) by a rationally designed cyclic analogue of myelin basic protein (MBP) epitope 72-85.

    Science.gov (United States)

    Tselios, T; Daliani, I; Deraos, S; Thymianou, S; Matsoukas, E; Troganis, A; Gerothanassis, I; Mouzaki, A; Mavromoustakos, T; Probert, L; Matsoukas, J

    2000-12-18

    In this report the rational design, synthesis and pharmacological properties of an amide-linked cyclic antagonist analogue of the guinea pig myelin basic protein epitope MBP(72-85) are described. Design of the potent cyclic analogue was based on 2D NOESY nuclear magnetic resonance and molecular dynamics studies carried out in the linear antagonist Ala81MBP(72-85). The cyclic antagonist completely prevented the induction of experimental allergic/autoimmune encephalomyelitis when coinjected with linear and cyclic agonist analogues MBP(72-85) and cyclo(2-9)MBP(72-85).

  4. Brain Basics

    Medline Plus

    Full Text Available ... as depression. The Growing Brain Inside the Brain: Neurons & Neural Circuits Neurons are the basic working unit of the brain ... specialized for the function of conducting messages. A neuron has three basic parts: Cell body which includes ...

  5. Brain Basics

    Medline Plus

    Full Text Available ... in Real Life Brain Research Glossary Brain Basics (PDF, 10 pages) Introduction Watch the Brain Basics video ... and epigenetic changes can be passed on to future generations. Further understanding of genes and epigenetics may ...

  6. Basic domains target protein subunits of the RNase MRP complex to the nucleolus independently of complex association.

    NARCIS (Netherlands)

    Eenennaam, H. van; Heijden, A.G. van der; Janssen, R.J.T.; Venrooij, W.J.W. van; Pruijn, G.J.M.

    2001-01-01

    The RNase MRP and RNase P ribonucleoprotein particles both function as endoribonucleases, have a similar RNA component, and share several protein subunits. RNase MRP has been implicated in pre-rRNA processing and mitochondrial DNA replication, whereas RNase P functions in pre-tRNA processing. Both

  7. Cation-exchange high-performance liquid chromatography: Separation of highly basic proteins using volatile acidic solvents

    NARCIS (Netherlands)

    Eijnden-van Raaij, A.J.M. van den; Koornneef, I.; Oostwaard, Th.M.J.; Laat, S.W. de; Zoelen, E.J.J. van

    1987-01-01

    The chromatographic behavior of a number of globular proteins was studied on a Bio-Sil TSK CM-2-SW weak cation exchange HPLC column under acidic conditions. A linear gradient of O-I M NH₄Ac in I M HOAc, inducing a convex pH gradient from 2.4-4.8, resulted in an excellent separation of highly

  8. Catalytic autoantibodies against myelin basic protein (MBP) isolated from serum of autistic children impair in vitro models of synaptic plasticity in rat hippocampus.

    Science.gov (United States)

    Gonzalez-Gronow, Mario; Cuchacovich, Miguel; Francos, Rina; Cuchacovich, Stephanie; Blanco, Angel; Sandoval, Rodrigo; Gomez, Cristian Farias; Valenzuela, Javier A; Ray, Rupa; Pizzo, Salvatore V

    2015-10-15

    Autoantibodies from autistic spectrum disorder (ASD) patients react with multiple proteins expressed in the brain. One such autoantibody targets myelin basic protein (MBP). ASD patients have autoantibodies to MBP of both the IgG and IgA classes in high titers, but no autoantibodies of the IgM class. IgA autoantibodies act as serine proteinases and degrade MBP in vitro. They also induce a decrease in long-term potentiation in the hippocampi of rats either perfused with or previously inoculated with this IgA. Because this class of autoantibody causes myelin sheath destruction in multiple sclerosis (MS), we hypothesized a similar pathological role for them in ASD. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. NMR and molecular dynamics studies of an autoimmune myelin basic protein peptide and its antagonist : structural implications for the MHC II (I-Au)–peptide complex from docking calculations

    NARCIS (Netherlands)

    Tzakos, A.G.; Fuchs, P.; van Nuland, N.A.J.; Troganis, A.; Tselios, T.; Deraos, S.; Gerothanassis, I.P.; Bonvin, A.M.J.J.

    2004-01-01

    Experimental autoimmune encephalomyelitis can be induced in susceptible animals by immunodominant determinants of myelin basic protein (MBP). To characterize the molecular features of antigenic sites important for designing experimental autoimmune encephalomyelitis suppressing molecules, we report

  10. The AAA+ proteins Pontin and Reptin enter adult age: from understanding their basic biology to the identification of selective inhibitors.

    Science.gov (United States)

    Matias, Pedro M; Baek, Sung Hee; Bandeiras, Tiago M; Dutta, Anindya; Houry, Walid A; Llorca, Oscar; Rosenbaum, Jean

    2015-01-01

    Pontin and Reptin are related partner proteins belonging to the AAA+ (ATPases Associated with various cellular Activities) family. They are implicated in multiple and seemingly unrelated processes encompassing the regulation of gene transcription, the remodeling of chromatin, DNA damage sensing and repair, and the assembly of protein and ribonucleoprotein complexes, among others. The 2nd International Workshop on Pontin and Reptin took place at the Instituto de Tecnologia Química e Biológica António Xavier in Oeiras, Portugal on October 10-12, 2014, and reported significant new advances on the mechanisms of action of these two AAA+ ATPases. The major points under discussion were related to the mechanisms through which these proteins regulate gene transcription, their roles as co-chaperones, and their involvement in pathophysiology, especially in cancer and ciliary biology and disease. Finally, they may become anticancer drug targets since small chemical inhibitors were shown to produce anti-tumor effects in animal models.

  11. Spermiogenesis and biflagellate spermatozoon of the teleost fish Lampanyctus crocodilus (Myctophiformes, Myctophidae): ultrastructure and characterisation of its sperm basic nuclear proteins.

    Science.gov (United States)

    Ribes, E; Cheema, M; González-Romero, R; Lloris, D; Ausió, J; Saperas, N

    2015-08-01

    We undertook an ultrastructural study of the spermiogenesis of the lanternfish Lampanyctus crocodilus (Myctophiformes, Myctophidae) with special emphasis on the condensation of chromatin and the biochemical characterisation of its sperm nuclear basic proteins (SNBPs). The round head of the early spermatid of L. crocodilus develops into a curved conical-shaped head in the spermatozoon. Two flagella, present even in the spermatid, are inserted laterally at the convex side of the sperm head. Both flagella possess an axoneme with a 9 + 0 instead of the typical 9 + 2 axonemal structure. Mitochondria undergo a characteristic redistribution during spermiogenesis. A reduced number of them are present lying away from the centrioles at both ends of the concave side of the sperm head. During the chromatin condensation stages in spermiogenesis, fibrogranular structures with granules of 25 ± 5 and 50 ± 5 nm can be observed in the early spermatid and develop into larger granules of about 150 ± 50 nm in the middle spermatid. The latter granules coalesce during the transition to the advanced spermatid and spermatozoon giving rise to highly condensed chromatin in the sperm cell. Protamines are the main SNBPs associated with this chromatin; however, they are unusually large and correspond to the largest protamines described in fish to date. Small stoichiometric amounts of histones and other basic proteins coexist with these protamines in the spermatozoon.

  12. An alternative pathway for gene regulation by Myc

    DEFF Research Database (Denmark)

    Peukert, K; Staller, P; Schneider, A

    1997-01-01

    The c-Myc protein activates transcription as part of a heteromeric complex with Max. However, Myc-transformed cells are characterized by loss of expression of several genes, suggesting that Myc may also repress gene expression. Two-hybrid cloning identifies a novel POZ domain Zn finger protein (Miz......-1; Myc-interacting Zn finger protein-1) that specifically interacts with Myc, but not with Max or USF. Miz-1 binds to start sites of the adenovirus major late and cyclin D1 promoters and activates transcription from both promoters. Miz-1 has a potent growth arrest function. Binding of Myc to Miz-1...... requires the helix-loop-helix domain of Myc and a short amphipathic helix located in the carboxy-terminus of Miz-1. Expression of Myc inhibits transactivation, overcomes Miz-1-induced growth arrest and renders Miz-1 insoluble in vivo. These processes depend on Myc and Miz-1 association and on the integrity...

  13. Phosphorylation and activation of protamine kinase by two forms of a myelin basic protein kinase from extracts of bovine kidney cortex.

    Science.gov (United States)

    Reddy, S A; Guo, H; Tarun, S Z; Damuni, Z

    1993-07-15

    Two myelin basic protein kinases designated MBPK-1 and MBPK-2 were purified to apparent homogeneity from extracts of bovine kidney cortex. The purified preparations exhibited an apparent M(r) approximately 40,000 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and approximately 42,000 (MBPK-1) and 45,000 (MBPK-2) by gel permeation chromatography. Up to 0.4 and 1.8 mol of phosphoryl groups were incorporated per mol of MBPK-1 and MBPK-2, respectively, on threonines following incubation with ATP. Autophosphorylation, incubation with protein phosphatase 2A2 (PP2A2), CD45, or T-cell protein tyrosine phosphatase did not affect MBPK-1 activity. Autophosphorylation increased by about 3-fold MBPK-2 activity. This autophosphorylation and activation was reversed by PP2A2 but not by CD45 or T-cell protein tyrosine phosphatase. MBPK-1 and MBPK-2 displayed a positive reaction with an antibody to mitogen-activated protein kinase. Purified preparations of protamine kinase were activated by about 1.5-6-fold and, after inactivation with PP2A2, were reactivated by about 30% by MBPK-1 and MBPK-2. Activation and reactivation correlated with the incorporation, respectively, of 0.1-0.5 and 0.5 mol of phosphoryl groups/mol of the protamine kinase on serines. The results show that MBPK-1 and MBPK-2 are protamine kinase-activating kinases and suggest that MBPK-1 and MBPK-2 may be related to mitogen-activated protein kinase.

  14. Bone morphogenetic proteins in tissue engineering: the road from the laboratory to the clinic, part I (basic concepts).

    Science.gov (United States)

    Bessa, P C; Casal, M; Reis, R L

    2008-01-01

    Discovered in 1965, bone morphogenetic proteins (BMPs) are a group of cytokines from the transforming growth factor-beta (TGFbeta) superfamily with significant roles in bone and cartilage formation. BMPs are used as powerful osteoinductive components of diverse tissue-engineering products for the healing of bone. Several BMPs with different physiological roles have been identified in humans. The purpose of this review is to cover the biological function of the main members of BMP family, the latest research on BMPs signalling pathways and advances in the production of recombinant BMPs for tissue engineering purposes. Copyright (c) 2008 John Wiley & Sons, Ltd.

  15. Basic electrotechnology

    CERN Document Server

    Ashen, R A

    2013-01-01

    BASIC Electrotechnology discusses the applications of Beginner's All-purpose Symbolic Instruction Code (BASIC) in engineering, particularly in solving electrotechnology-related problems. The book is comprised of six chapters that cover several topics relevant to BASIC and electrotechnology. Chapter 1 provides an introduction to BASIC, and Chapter 2 talks about the use of complex numbers in a.c. circuit analysis. Chapter 3 covers linear circuit analysis with d.c. and sinusoidal a.c. supplies. The book also discusses the elementary magnetic circuit theory. The theory and performance of two windi

  16. Unique CCT repeats mediate transcription of the TWIST1 gene in mesenchymal cell lines

    International Nuclear Information System (INIS)

    Ohkuma, Mizue; Funato, Noriko; Higashihori, Norihisa; Murakami, Masanori; Ohyama, Kimie; Nakamura, Masataka

    2007-01-01

    TWIST1, a basic helix-loop-helix transcription factor, plays critical roles in embryo development, cancer metastasis and mesenchymal progenitor differentiation. Little is known about transcriptional regulation of TWIST1 expression. Here we identified DNA sequences responsible for TWIST1 expression in mesenchymal lineage cell lines. Reporter assays with TWIST1 promoter mutants defined the -102 to -74 sequences that are essential for TWIST1 expression in human and mouse mesenchymal cell lines. Tandem repeats of CCT, but not putative CREB and NF-κB sites in the sequences substantially supported activity of the TWIST1 promoter. Electrophoretic mobility shift assay demonstrated that the DNA sequences with the CCT repeats formed complexes with nuclear factors, containing, at least, Sp1 and Sp3. These results suggest critical implication of the CCT repeats in association with Sp1 and Sp3 factors in sustaining expression of the TWIST1 gene in mesenchymal cells

  17. Snail regulates p21WAF/CIP1 expression in cooperation with E2 A and Twist

    International Nuclear Information System (INIS)

    Takahashi, Eishi; Funato, Noriko; Higashihori, Norihisa; Hata, Yuiro; Gridley, Thomas; Nakamura, Masataka

    2004-01-01

    Snail, a zinc-finger transcriptional repressor, is essential for mesoderm and neural crest cell formation and epithelial-mesenchymal transition. The basic helix-loop-helix transcription factors E2A and Twist have been linked with Snail during embryonic development. In this study, we examined the role of Snail in cellular differentiation through regulation of p21 WAF/CIP1 expression. A reporter assay with the p21 promoter demonstrated that Snail inhibited expression of p21 induced by E2A. Co-expression of Snail with Twist showed additive inhibitory effects. Deletion mutants of the p21 promoter revealed that sequences between -270 and -264, which formed a complex with unidentified nuclear factor(s), were critical for E2A and Snail function. The E2A-dependent expression of the endogenous p21 gene was also inhibited by Snail

  18. A BAC transgenic Hes1-EGFP reporter reveals novel expression domains in mouse embryos

    DEFF Research Database (Denmark)

    Klinck, Rasmus; Füchtbauer, Ernst-Martin; Ahnfelt-Rønne, Jonas

    2011-01-01

    Expression of the basic helix-loop-helix factor Hairy and Enhancer of Split-1 (Hes1) is required for normal development of a number of tissues during embryonic development. Depending on context, Hes1 may act as a Notch signalling effector which promotes the undifferentiated and proliferative state...... of progenitor cells, but increasing evidence also points to Notch independent regulation of Hes1 expression. Here we use high resolution confocal scanning of EGFP in a novel BAC transgenic mouse reporter line, Tg(Hes1-EGFP)(1Hri), to analyse Hes1 expression from embryonic day 7.0 (e7.0). Our data recapitulates...... the role of Hes1 in a number of different research areas including organ specification, development and regeneration....

  19. Accurate discrimination of bHLH domains in plants, animals, and fungi using biologically meaningful sites.

    Science.gov (United States)

    Sailsbery, Joshua K; Dean, Ralph A

    2012-08-24

    The highly conserved bHLH (basic Helix-Loop-Helix) domain, found in many transcription factors, has been well characterized separately in Plants, Animals, and Fungi. While conserved, even functionally constrained sites have varied since the Eukarya split. Our research identifies those slightly variable sites that were highly characteristic of Plants, Animals, or Fungi. Through discriminant analysis, we identified five highly discerning DNA-binding amino acid sites. Additionally, by incorporating Kingdom specific HMMs, we were able to construct a tool to quickly and accurately identify and classify bHLH sequences using these sites. We conclude that highly discerning sites identified through our analysis were likely under functional constraints specific to each Kingdom. We also demonstrated the utility of our tool by identifying and classifying previously unknown bHLH domains in both characterized genomes and from sequences in a large environmental sample.

  20. The 21.5-kDa isoform of myelin basic protein has a non-traditional PY-nuclear-localization signal

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Graham S.T.; Seymour, Lauren V. [Molecular and Cellular Biology, University of Guelph, Guelph, Ontario (Canada); Boggs, Joan M. [Molecular Structure and Function, Research Institute, Hospital for Sick Children, and Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario (Canada); Harauz, George, E-mail: gharauz@uoguelph.ca [Molecular and Cellular Biology, University of Guelph, Guelph, Ontario (Canada)

    2012-06-15

    Highlights: Black-Right-Pointing-Pointer Full-length 21.5-kDa MBP isoform is translocated to the nucleus. Black-Right-Pointing-Pointer We hypothesized that the exon-II-encoded sequence contained the NLS. Black-Right-Pointing-Pointer We mutated this sequence in RFP-tagged constructs and transfected N19-cells. Black-Right-Pointing-Pointer Abolition of two key positively-charged residues resulted in loss of nuclear-trafficking. Black-Right-Pointing-Pointer The 21.5-kDa isoform of classic MBP contains a non-traditional PY-NLS. -- Abstract: The predominant 18.5-kDa classic myelin basic protein (MBP) is mainly responsible for compaction of the myelin sheath in the central nervous system, but is multifunctional, having numerous interactions with Ca{sup 2+}-calmodulin, actin, tubulin, and SH3-domains, and can tether these proteins to a lipid membrane in vitro. The full-length 21.5-kDa MBP isoform has an additional 26 residues encoded by exon-II of the classic gene, which causes it to be trafficked to the nucleus of oligodendrocytes (OLGs). We have performed site-directed mutagenesis of selected residues within this segment in red fluorescent protein (RFP)-tagged constructs, which were then transfected into the immortalized N19-OLG cell line to view protein localization using epifluorescence microscopy. We found that 21.5-kDa MBP contains two non-traditional PY-nuclear-localization signals, and that arginine and lysine residues within these motifs were involved in subcellular trafficking of this protein to the nucleus, where it may have functional roles during myelinogenesis.

  1. Basic Equations in Statics and Kinetics of Protein Polymerization and the Mechanism of the Formation and Dissociation of Amyloid Fibrils Revealed by Pressure Perturbation.

    Science.gov (United States)

    Tachibana, Hideki

    2015-01-01

    Studies of the pressure-dissociation of several amyloid or amyloid-like fibrils have shown that the fibril state is considerably voluminous. Quantitative characterization of the protein fibrillation reaction with respect to volumetric parameters is necessary to elucidate mechanisms of amyloid fibrillation in molecular terms such as protein cavity and hydration. Here we discuss, firstly, basic equations in statics and kinetics of protein polymerization as employed to obtain thermodynamic, volumetric, and kinetic parameters. Equilibrium treatment of the reactions with the scheme such as one-step polymerization, linear-association polymerization, or nucleation-dependent polymerization, and kinetic treatment of seeded linear-polymerization or spontaneous nucleation-elongation polymerization are described. In particular we will detail kinetics of the dissociation of fibrils which have been produced under the linear-association mechanism and therefore the length-distribution of which conforms to a geometric sequence in the degree of polymerization with a common ratio r, which is less than, and usually very close to, unity. In this case, an observed macroscopic rate of dissociation is shown to be a product of the microscopic elementary dissociation rate constant and a factor (1-r), extremely reduced compared with the intrinsic elementary rate. Secondly, we discuss protein conformational states in fibrillogenesis with molecular and volumetric observations reported, such as the unfolded state responsible for the association with seeds and the extension of amyloid fibrils, the transition state in which protein cavity formation and dehydration occur to intermediate levels, and the fibril state in which they occur to final respective levels which, in some cases, depend on the maturity of the fibril.

  2. Responsiveness to 6-n-propylthiouracil (PROP is associated with salivary levels of two specific basic proline-rich proteins in humans.

    Directory of Open Access Journals (Sweden)

    Tiziana Cabras

    Full Text Available Thiourea tasting can be predictive of individual differences in bitter taste responses, general food preferences and eating behavior, and could be correlated with saliva chemical composition. We investigated the possible relationship between PROP bitter taste responsiveness and the salivary proteome in subjects genotyped for TAS2R38 and gustin gene polymorphisms. Taste perception intensity evoked by PROP and NaCl solutions was measured in sixty-three volunteers (21 males, 42 females, age 25±3 y to establish their PROP taster status, and 24 PROP super-tasters and 21 nontasters were selected to participate in the study. TAS2R38 and gustin gene molecular analysis were performed using PCR techniques. Qualitative and quantitative determination of salivary proteins was performed by HPLC-ESI-MS before and after PROP taste stimulation. PROP super-tastings was strongly associated with the 'taster' variant (PAV haplotype of TAS2R38 and the A allele of rs2274333 polymorphism in the gustin gene and nontasting was associated with the minor alleles at both loci. ANOVA revealed that basal levels of II-2 and Ps-1 proteins, belonging to the basic proline-rich protein (bPRPs family, were significantly higher in PROP super-taster than in nontaster un-stimulated saliva, and that PROP stimulation elicited a rapid increase in the levels of these same proteins only in PROP super-taster saliva. These data show for the first time that responsiveness to PROP is associated with salivary levels of II-2 peptide and Ps-1 protein, which are products of the PRB1 gene. These findings suggest that PRB1, in addition to TAS2R38 and gustin, could contribute to individual differences in thiourea sensitivity, and the expression of the PROP phenotype as a complex genetic trait.

  3. Anesthesia Basics

    Science.gov (United States)

    ... Staying Safe Videos for Educators Search English Español Anesthesia Basics KidsHealth / For Teens / Anesthesia Basics What's in ... español Conceptos básicos sobre la anestesia What Is Anesthesia? No doubt about it, getting an operation can ...

  4. Brain Basics

    Medline Plus

    Full Text Available ... pituitary-adrenal (HPA) axis. Brain Basics in Real Life Brain Basics in Real Life—How Depression affects the Brain Meet Sarah Sarah ... having trouble coping with the stresses in her life. She began to think of suicide because she ...

  5. T-helper lymphocytes specific for myelin basic protein: low-density activation prolongs a postactivation refractory phase marked by decreased pathogenicity and enhanced sensitivity to anergy.

    Science.gov (United States)

    Mannie, M D; White, G A; Lake, K R; Nardella, J P; Marinakis, C A; McConnell, T J

    1996-08-25

    Regulation of experimental autoimmune encephalomyelitis (EAE) in Lewis rats may involve activation-dependent negative feedback pathways of T-helper cells. Previous studies have shown that T-helper cells specific for myelin basic protein exhibit a postactivation refractory phase during which antigenic restimulation elicits proliferation without production of IL-2. Herein, we show that postactivation refractoriness inhibits regeneration of EAE transfer activity and is manifest by a lack of IL-2 mRNA accumulation despite induction of normal levels of IL-4 mRNA. Preactivated refractory T cells were substantially more susceptible than resting T cells to the induction of anergy. Low-density T cell activation or subcloning prolonged the duration of the refractory phase and engendered long-term desensitization of T cells marked by a blockade of IL-2 production and by enhanced susceptibility to anergy. Overall, these results support the concept that postactivation refractoriness controls the pathogenicity and differentiation of T-helper cells.

  6. Structural insight into the function of myelin basic protein as a ligand for integrin αMβ2

    DEFF Research Database (Denmark)

    Stapulionis, Romualdas; Oliveira, Cristiano; Gjelstrup, Mikkel Carstensen

    2008-01-01

    Multiple sclerosis (MS) is an inflammatory disease where phagocytic cells infiltrate the nerve tissue and act as terminal agents in destruction of the myelin sheath. However, the mechanism that triggers the ability of these cells to recognize myelin remains obscure. We show that myelin basic...... protein (MBP), a major autoantigen in MS, is a potent and specific ligand for the integrin αMβ2 (Mac-1, CD11b/CD18) expressed mainly on phagocytic cells. MBP undergoes a dramatic conformational change when liberated from the lipid-rich environment of the myelin sheath. The MS drug glatiramer acetate...... mimics the conformationally labile regions of MBP, interacts in the unfolded state strongly with αMβ2, and inhibits the MBP binding to αMβ2. Our study reveals a link between MBP, glatiramer acetate, and the αMβ2 integrin, and suggests a new model for MS pathogenesis based on the recognition of unfolded...

  7. Stabilization of peptide guinea pig myelin basic protein 72-85 by N-terminal acetylation-implications for immunological studies.

    Science.gov (United States)

    de Haan, Ellen C; Wauben, Marca H M; Wagenaar-Hilbers, Josée P A; Grosfeld-Stulemeyer, Mayken C; Rijkers, Dirk T S; Moret, Ed E; Liskamp, Rob M J

    2004-02-01

    Peptide gpMBP72-85, containing amino acids 72-85 of guinea pig myelin basic protein is commonly used to induce experimental autoimmune encephalomyelitis in Lewis rats. The N-terminal glutamine in this peptide can cyclize to pyroglutamic acid, leading to loss of the first MHC anchor for binding to MHC class II. Acetylation of the peptide N-terminus prevents pyroglutamic acid formation and ensures a constant quality. An increased MHC binding affinity after N-terminal acetylation was observed. This modification also enhanced T cell proliferation of a gpMBP reactive T cell clone. The encephalitogenicity of peptide gpMBP72-85 was unaffected by acetylation. It is concluded that acetylation improves the chemical stability of gpMBP72-85, and is not detrimental but rather favorable for its biochemical and immunological, in vitro, and in vivo behavior.

  8. Basic hydraulics

    CERN Document Server

    Smith, P D

    1982-01-01

    BASIC Hydraulics aims to help students both to become proficient in the BASIC programming language by actually using the language in an important field of engineering and to use computing as a means of mastering the subject of hydraulics. The book begins with a summary of the technique of computing in BASIC together with comments and listing of the main commands and statements. Subsequent chapters introduce the fundamental concepts and appropriate governing equations. Topics covered include principles of fluid mechanics; flow in pipes, pipe networks and open channels; hydraulic machinery;

  9. Computational modeling of the bHLH domain of the transcription factor TWIST1 and R118C, S144R and K145E mutants

    Directory of Open Access Journals (Sweden)

    Maia Amanda M

    2012-07-01

    Full Text Available Abstract Background Human TWIST1 is a highly conserved member of the regulatory basic helix-loop-helix (bHLH transcription factors. TWIST1 forms homo- or heterodimers with E-box proteins, such as E2A (isoforms E12 and E47, MYOD and HAND2. Haploinsufficiency germ-line mutations of the twist1 gene in humans are the main cause of Saethre-Chotzen syndrome (SCS, which is characterized by limb abnormalities and premature fusion of cranial sutures. Because of the importance of TWIST1 in the regulation of embryonic development and its relationship with SCS, along with the lack of an experimentally solved 3D structure, we performed comparative modeling for the TWIST1 bHLH region arranged into wild-type homodimers and heterodimers with E47. In addition, three mutations that promote DNA binding failure (R118C, S144R and K145E were studied on the TWIST1 monomer. We also explored the behavior of the mutant forms in aqueous solution using molecular dynamics (MD simulations, focusing on the structural changes of the wild-type versus mutant dimers. Results The solvent-accessible surface area of the homodimers was smaller on wild-type dimers, which indicates that the cleft between the monomers remained more open on the mutant homodimers. RMSD and RMSF analyses indicated that mutated dimers presented values that were higher than those for the wild-type dimers. For a more careful investigation, the monomer was subdivided into four regions: basic, helix I, loop and helix II. The basic domain presented a higher flexibility in all of the parameters that were analyzed, and the mutant dimer basic domains presented values that were higher than the wild-type dimers. The essential dynamic analysis also indicated a higher collective motion for the basic domain. Conclusions Our results suggest the mutations studied turned the dimers into more unstable structures with a wider cleft, which may be a reason for the loss of DNA binding capacity observed for in vitro

  10. Brain Basics

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    Full Text Available ... normal brain development and function can go awry, leading to mental illnesses. Brain Basics will introduce you ... of DNA. Sometimes this copying process is imperfect, leading to a gene mutation that causes the gene ...

  11. Brain Basics

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    Full Text Available ... Real Life Brain Basics in Real Life—How Depression affects the Brain Meet Sarah Sarah is a ... in controlling movement, managing the release of various hormones, and aiding the flow of information to the ...

  12. Brain Basics

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    Full Text Available ... Events About Us Home > Health & Education > Educational Resources Brain Basics Introduction The Growing Brain The Working Brain ... to mental disorders, such as depression. The Growing Brain Inside the Brain: Neurons & Neural Circuits Neurons are ...

  13. Basic Finance

    Science.gov (United States)

    Vittek, J. F.

    1972-01-01

    A discussion of the basic measures of corporate financial strength, and the sources of the information is reported. Considered are: balance sheet, income statement, funds and cash flow, and financial ratios.

  14. Brain Basics

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    Full Text Available ... effectively coordinate the billions of cells in the body, the results can affect many aspects of life. ... messages. A neuron has three basic parts: Cell body which includes the nucleus, cytoplasm, and cell organelles. ...

  15. Brain Basics

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    Full Text Available ... Real Life Brain Basics in Real Life—How Depression affects the Brain Meet Sarah Sarah is a ... brain. DNA —The "recipe of life," containing inherited genetic information that helps to define physical and some ...

  16. Brain Basics

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    Full Text Available ... Brain Basics provides information on how the brain works, how mental illnesses are disorders of the brain, ... learning more about how the brain grows and works in healthy people, and how normal brain development ...

  17. Brain Basics

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    Full Text Available ... science, such as: How the brain develops How genes and the environment affect the brain The basic ... that with brain development in people mental disorders. Genes and environmental cues both help to direct this ...

  18. Brain Basics

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    Full Text Available ... Real Life Brain Basics in Real Life—How Depression affects the Brain Meet Sarah Sarah is a ... blues" from time to time. In contrast, major depression is a serious disorder that lasts for weeks. ...

  19. Brain Basics

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    Full Text Available ... How the brain develops How genes and the environment affect the brain The basic structure of the ... inside contents of the cell from its surrounding environment and controls what enters and leaves the cell, ...

  20. Brain Basics

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    Full Text Available ... depression. The Growing Brain Inside the Brain: Neurons & Neural Circuits Neurons are the basic working unit of ... but sometimes give rise to disabilities or diseases. neural circuit —A network of neurons and their interconnections. ...

  1. Brain Basics

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    Full Text Available ... in the anatomy, physiology, and chemistry of the nervous system. When the brain cannot effectively coordinate the billions ... the basic working unit of the brain and nervous system. These cells are highly specialized for the function ...

  2. Brain Basics

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    Full Text Available ... the anatomy, physiology, and chemistry of the nervous system. When the brain cannot effectively coordinate the billions ... basic working unit of the brain and nervous system. These cells are highly specialized for the function ...

  3. Brain Basics

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    Full Text Available ... segment of DNA that contains codes to make proteins and other important body chemicals. DNA also includes ... the gene to code for a slightly different protein. Some mutations are harmless, some can be helpful, ...

  4. The Arabidopsis GAGA-Binding Factor BASIC PENTACYSTEINE6 Recruits the POLYCOMB-REPRESSIVE COMPLEX1 Component LIKE HETEROCHROMATIN PROTEIN1 to GAGA DNA Motifs.

    Science.gov (United States)

    Hecker, Andreas; Brand, Luise H; Peter, Sébastien; Simoncello, Nathalie; Kilian, Joachim; Harter, Klaus; Gaudin, Valérie; Wanke, Dierk

    2015-07-01

    Polycomb-repressive complexes (PRCs) play key roles in development by repressing a large number of genes involved in various functions. Much, however, remains to be discovered about PRC-silencing mechanisms as well as their targeting to specific genomic regions. Besides other mechanisms, GAGA-binding factors in animals can guide PRC members in a sequence-specific manner to Polycomb-responsive DNA elements. Here, we show that the Arabidopsis (Arabidopsis thaliana) GAGA-motif binding factor protein basic pentacysteine6 (BPC6) interacts with like heterochromatin protein1 (LHP1), a PRC1 component, and associates with vernalization2 (VRN2), a PRC2 component, in vivo. By using a modified DNA-protein interaction enzyme-linked immunosorbant assay, we could show that BPC6 was required and sufficient to recruit LHP1 to GAGA motif-containing DNA probes in vitro. We also found that LHP1 interacts with VRN2 and, therefore, can function as a possible scaffold between BPC6 and VRN2. The lhp1-4 bpc4 bpc6 triple mutant displayed a pleiotropic phenotype, extreme dwarfism and early flowering, which disclosed synergistic functions of LHP1 and group II plant BPC members. Transcriptome analyses supported this synergy and suggested a possible function in the concerted repression of homeotic genes, probably through histone H3 lysine-27 trimethylation. Hence, our findings suggest striking similarities between animal and plant GAGA-binding factors in the recruitment of PRC1 and PRC2 components to Polycomb-responsive DNA element-like GAGA motifs, which must have evolved through convergent evolution. © 2015 American Society of Plant Biologists. All Rights Reserved.

  5. Studies on an acetylcholine binding protein identify a basic residue in loop G on the β1 strand as a new structural determinant of neonicotinoid actions.

    Science.gov (United States)

    Ihara, Makoto; Okajima, Toshihide; Yamashita, Atsuko; Oda, Takuma; Asano, Takuya; Matsui, Mikana; Sattelle, David B; Matsuda, Kazuhiko

    2014-12-01

    Neonicotinoid insecticides target insect nicotinic acetylcholine receptors (nAChRs). Their widespread use and possible risks to pollinators make it extremely urgent to understand the mechanisms underlying their actions on insect nAChRs. We therefore elucidated X-ray crystal structures of the Lymnaea stagnalis acetylcholine binding protein (Ls-AChBP) and its Gln55Arg mutant, more closely resembling insect nAChRs, in complex with a nitromethylene imidacloprid analog (CH-IMI) and desnitro-imidacloprid metabolite (DN-IMI) as well as commercial neonicotinoids, imidacloprid, clothianidin, and thiacloprid. Unlike imidacloprid, clothianidin, and CH-IMI, thiacloprid did not stack with Tyr185 in the wild-type Ls-AChBP, but did in the Gln55Arg mutant, interacting electrostatically with Arg55. In contrast, DN-IMI lacking the NO2 group was directed away from Lys34 and Arg55 to form hydrogen bonds with Tyr89 in loop A and the main chain carbonyl of Trp143 in loop B. Unexpectedly, we found that several neonicotinoids interacted with Lys34 in loop G on the β1 strand in the crystal structure of the Gln55Arg mutant. Basic residues introduced into the α7 nAChR at positions equivalent to AChBP Lys34 and Arg55 enhanced agonist actions of neonicotinoids, while reducing the actions of acetylcholine, (-)-nicotine, and DN-IMI. Thus, not only the basic residues in loop D, but also those in loop G determine the actions of neonicotinoids. These novel findings provide new insights into the modes of action of neonicotinoids and emerging derivatives. Copyright © 2014 by The American Society for Pharmacology and Experimental Therapeutics.

  6. Basic electronics

    CERN Document Server

    Holbrook, Harold D

    1971-01-01

    Basic Electronics is an elementary text designed for basic instruction in electricity and electronics. It gives emphasis on electronic emission and the vacuum tube and shows transistor circuits in parallel with electron tube circuits. This book also demonstrates how the transistor merely replaces the tube, with proper change of circuit constants as required. Many problems are presented at the end of each chapter. This book is comprised of 17 chapters and opens with an overview of electron theory, followed by a discussion on resistance, inductance, and capacitance, along with their effects on t

  7. Basic conceptions

    International Nuclear Information System (INIS)

    Khasanov, A.Kh.

    1988-01-01

    In this part of book author presents the basic conceptions of minerals studying. The course of minerals deposits is the most important branch of geology science and studying the geology, material constitution, formation conditions and regularity of distribution in earth crust different types of mineral raw materials

  8. Brain Basics

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    Full Text Available ... mental illnesses. Search the NIMH Website: Home Health & Education Mental Health Information Statistics Consumer Health Publications Help for Mental Illnesses Clinical Trials Outreach Research Priorities Funding Labs at ... Health & Education > Educational Resources Brain Basics Introduction The Growing Brain ...

  9. Brain Basics

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    Full Text Available ... Real Life Brain Basics in Real Life—How Depression affects the Brain Meet Sarah Sarah is a ... MSC 9663 Bethesda, MD 20892-9663 Follow Us Facebook Twitter YouTube Google Plus NIMH Newsletter NIMH RSS ...

  10. Brain Basics

    Medline Plus

    Full Text Available ... by which the cell sends information to receiving neurons. cell body —Contains the nucleus and cytoplasm of a ... circuit —A network of neurons and their interconnections. neuron —A nerve cell that is the basic, working unit of the ...

  11. Brain Basics

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    Full Text Available ... Join A Study News & Events News & Events Home Science News Events Multimedia Social Media Press Resources Newsletters NIMH News Feeds About Us About Us Home About the Director Advisory Boards and ... Basics will introduce you to some of this science, such as: How the brain develops How genes ...

  12. Ethanol Basics

    Energy Technology Data Exchange (ETDEWEB)

    None

    2015-01-30

    Ethanol is a widely-used, domestically-produced renewable fuel made from corn and other plant materials. More than 96% of gasoline sold in the United States contains ethanol. Learn more about this alternative fuel in the Ethanol Basics Fact Sheet, produced by the U.S. Department of Energy's Clean Cities program.

  13. The differences in heparin binding for the C-terminal basic-sequence-rich peptides of HPV-16 and HPV-18 capsid protein L1

    International Nuclear Information System (INIS)

    Sun Jian; Yu Jisheng; Yu Zhiwu; Zha Xiao; Wu Yuqing

    2012-01-01

    Graphial abstract: The differences in heparin binding for the C-terminal basic-sequence-rich peptides of HPV-16 and HPV-18 capsid protein L1. Highlights: ► Several driving forces contribute to the interaction between heparin and peptides. ► C-terminal of HPV L1 is a potential candidate for the attachment to host cells. ► The C-terminal peptides of HPV-16 and -18 L1 have different heparin-binding. ► The different heparin-binding provides an explanation for the distinct prevalences. - Abstract: The high-risk types of human papillomaviruses (HPV) HPV-16 and -18 are the predominant types associated with cervical cancer. HPV-16 and -18 account for about 50% and 20%, respectively, of cervical cancers worldwide. While the reason and molecular mechanism of the distinct prevalence and distributions between them remain poorly understood, the binding affinity of cell surface receptor with capsid proteins, especially L1, may be involved. We examined heparin binding with two synthetic peptides corresponding to the 14 amino acid C-terminal peptides of HPV-16 and -18 L1 with the goal of comparing the equivalent residues in different HPV types. Using isothermal titration calorimetry (ITC) and static right-angle light scattering (SLS), we determined the binding constant K, reaction enthalpy ΔH, and other thermodynamic parameters in the interaction. Especially, we assessed the role of specific residues in binding with heparin by comparing the NMR spectra of free and heparin-bound peptides.

  14. Development and Pre-Clinical Evaluation of Recombinant Human Myelin Basic Protein Nano Therapeutic Vaccine in Experimental Autoimmune Encephalomyelitis Mice Animal Model

    Science.gov (United States)

    Al-Ghobashy, Medhat A.; Elmeshad, Aliaa N.; Abdelsalam, Rania M.; Nooh, Mohammed M.; Al-Shorbagy, Muhammad; Laible, Götz

    2017-04-01

    Recombinant human myelin basic protein (rhMBP) was previously produced in the milk of transgenic cows. Differences in molecular recognition of either hMBP or rhMBP by surface-immobilized anti-hMBP antibodies were demonstrated. This indicated differences in immunological response between rhMBP and hMBP. Here, the activity of free and controlled release rhMBP poly(ε-caprolactone) nanoparticles (NPs), as a therapeutic vaccine against multiple sclerosis (MS) was demonstrated in experimental autoimmune encephalomyelitis (EAE) animal model. Following optimization of nanoformulation, discrete spherical, rough-surfaced rhMBP NPs with high entrapment efficiency and controlled release pattern were obtained. Results indicated that rhMBP was loaded into and electrostatically adsorbed onto the surface of NPs. Subcutaneous administration of free or rhMBP NPs before EAE-induction reduced the average behavioral score in EAE mice and showed only mild histological alterations and preservation of myelin sheath, with rhMBP NPs showing increased protection. Moreover, analysis of inflammatory cytokines (IFN-γ and IL-10) in mice brains revealed that pretreatment with free or rhMBP NPs significantly protected against induced inflammation. In conclusion: i) rhMBP ameliorated EAE symptoms in EAE animal model, ii) nanoformulation significantly enhanced efficacy of rhMBP as a therapeutic vaccine and iii) clinical investigations are required to demonstrate the activity of rhMBP NPs as a therapeutic vaccine for MS.

  15. T cell recognition of rat myelin basic protein as a TCR antagonist inhibits reciprocal activation of antigen-presenting cells and engenders resistance to experimental autoimmune encephalomyelitis.

    Science.gov (United States)

    Walker, M R; Mannie, M D

    2001-06-01

    The aim of this study was to assess whether T cell recognition of myelin basic protein (MBP) as a partially antagonistic self antigen regulates the reciprocal activation of professional antigen-presenting cells (APC). This study focused on the rat 3H3 T cell clone that recognized guinea pig (GP) MBP as a full agonist and self rat (R) MBP as a partial agonist. In cultures of 3H3 T cells and splenic APC, the agonist GPMBP elicited several responses by splenic APC, including production of nitric oxide, down-regulation of I-A, induction of B7.1 and B7.2, and prolongation of APC survival. RMBP stimulated a partial increase in production of nitric oxide, partially promoted survival of splenic APC, but did not alter expression of I-A, B7.1, or B7.2 on splenic APC. In the presence ofGPMBP, RMBP antagonized agonist-stimulated induction of B7 molecules, reversed the loss of I-A, and promoted the generation of I-A(+), costimulus-deficient APC. Furthermore, 3H3 T cells cultured with RMBP and irradiated splenocytes reduced the severity of EAE upon adoptive transfer into naive rat recipients subsequently challenged with an encephalitogenic dose of GPMBP/CFA. Overall, this study indicates that T cell receptor antagonism blocks T cell activation, inhibits feedback activation of splenic APC, and promotes T cell-dependent regulatory activities in EAE.

  16. Fine T cell receptor repertoire analysis of spinal cord T cells responding to the major and minor epitopes of myelin basic protein during rat autoimmune encephalomyelitis.

    Science.gov (United States)

    Matsumoto, Y; Jee, Y; Sugisaki, M; Kim, G; Tanuma, N

    2000-01-01

    Experimental autoimmune encephalomyelitis is a disease induced by neuroantigen-reactive T cells bearing particular types of T cell receptor (TCR). Although the nature of TCRs of encephalitogenic T cells has been partially delineated using encephalitogenic T cell clones established in vitro, the entire TCR repertoire formed in situ after immunization with neuroantigen remains unclear. In the present study, we immunized Lewis rats with myelin basic protein (MBP) and its fragment peptides and determined the TCR repertoire of spinal cord T cells formed after the immunization by CDR3 spectra-typing. It was revealed that the oligoclonal expansion of Vbeta2, Vbeta8.2, and Vbeta17 spectratypes was detectable after immunization with guinea pig MBP and its immunodominant epitope, the 68-88 sequence, whereas immunization with a peptide containing a minor epitope induced Vbeta10 expansion. Immunization with rat MBP induced much broader TCR Vbeta expansion (all of the above Vbetas plus Vbeta3). These findings suggest that TCRs activated by immunization with guinea pig MBP used as heteroclitic immunogen recognize autoantigen, rat MBP. Furthermore, the strategy used in this study gives insight into the pathogenesis of autoimmune disease and provides useful information for designing TCR-based immunotherapy.

  17. Glutamine rich and basic region/leucine zipper (bZIP) domains stabilize cAMP-response element-binding protein (CREB) binding to chromatin.

    Science.gov (United States)

    Mayr, Bernhard M; Guzman, Ernesto; Montminy, Marc

    2005-04-15

    We have examined the dynamics of cAMP-response element-binding protein (CREB) binding to chromatin in live cells using fluorescence recovery after photobleaching (FRAP). CREB was found to bind to target sites with a residence time of 100 s, and exposure to a cAMP agonist had no effect on these kinetics. In addition to the basic region/leucine zipper (bZIP) domain, a glutamine-rich trans-activation domain in CREB called Q2 also appeared to be critical for promoter occupancy. Indeed, mutations in Q2 that reduced residence time by FRAP assay disrupted target gene activation via CREB in cells exposed to a cAMP agonist. Notably, insertion of the glutamine-rich B trans-activation domain of SP1 into a mutant CREB polypeptide lacking Q2 stabilized CREB occupancy and rescued target gene activation. These results suggest a novel mechanism by which the family of glutamine-rich activators promotes cellular gene expression.

  18. Wavelet basics

    CERN Document Server

    Chan, Y T

    1995-01-01

    Since the study of wavelets is a relatively new area, much of the research coming from mathematicians, most of the literature uses terminology, concepts and proofs that may, at times, be difficult and intimidating for the engineer. Wavelet Basics has therefore been written as an introductory book for scientists and engineers. The mathematical presentation has been kept simple, the concepts being presented in elaborate detail in a terminology that engineers will find familiar. Difficult ideas are illustrated with examples which will also aid in the development of an intuitive insight. Chapter 1 reviews the basics of signal transformation and discusses the concepts of duals and frames. Chapter 2 introduces the wavelet transform, contrasts it with the short-time Fourier transform and clarifies the names of the different types of wavelet transforms. Chapter 3 links multiresolution analysis, orthonormal wavelets and the design of digital filters. Chapter 4 gives a tour d'horizon of topics of current interest: wave...

  19. Characterization of CgHIFα-Like, a Novel bHLH-PAS Transcription Factor Family Member, and Its Role under Hypoxia Stress in the Pacific Oyster Crassostrea gigas.

    Directory of Open Access Journals (Sweden)

    Ting Wang

    Full Text Available Hypoxia-inducible factor (HIF, a critical member of the basic-helix-loop-helix (bHLH-containing Per-Arnt-Sim (PAS protein family, is a master transcription factor involved in maintaining oxygen homeostasis. In the present study, we isolated and characterized a novel bHLH-PAS family member, CgHIFα-like gene, from the Pacific oyster Crassostrea gigas, and determined its importance during hypoxia stress. The 3020-bp CgHIFα-like cDNA encoded a protein of 888 amino acids. The predicted CgHIFα-like amino acid sequence was conserved in the N-terminal bHLH, PAS, and PAC domains (but not in the C-terminal domain and was most closely related to the HIF family in the bHLH-PAS protein phylogenic tree. Similar to the mammalian HIF-1α, CgHIFα-like could be expressed as four mRNA isoforms containing alternative 5'-untranslated regions and different translation initiation codons. At the mRNA level, these isoforms were expressed in a tissue-specific manner and showed increased transcription to varying degrees under hypoxic conditions. Additionally, the western blot analysis demonstrated that CgHIFα-like was induced by hypoxia. Electrophoretic mobility shift assay indicated that CgHIFα-like could bind to the hypoxia responsive element (HRE, whereas dual-luciferase reporter analysis demonstrated that CgHIFα-like could transactivate the reporter gene containing the HREs. In addition to CgHIFα-like, we identified CgARNT from the C. gigas, analyzed its expression pattern, and confirmed its interaction with CgHIFα-like using a yeast two-hybrid assay. In conclusion, this is the first report on the cloning and characterization of a novel hypoxia transcription factor in mollusks, which could accumulate under hypoxia and regulate hypoxia related gene expression by binding to HRE and dimerizing with CgARNT. As only one member of HIF has been identified in invertebrates to date, our results provide new insights into the unique mechanisms of hypoxia tolerance in

  20. Two LcbHLH transcription factors interacting with LcMYB1 in regulating late structural genes of anthocyanin biosynthesis in Nicotiana and Litchi chinensis during anthocyanin accumulation

    Directory of Open Access Journals (Sweden)

    Biao eLai

    2016-02-01

    Full Text Available Anthocyanin biosynthesis requires the MYB-bHLH-WD40 protein complex to activate the late biosynthetic genes. LcMYB1 was thought to act as key regulator in anthocyanin biosynthesis of litchi. However, basic helix-loop-helix proteins (bHLHs as partners have not been identified yet. The present study describes the functional characterization of three litchi bHLH candidate anthocyanin regulators, LcbHLH1, LcbHLH2 and LcbHLH3. Although these three litchi bHLHs phylogenetically clustered with bHLH proteins involved in anthcoyanin biosynthesis in other plant, only LcbHLH1 and LcbHLH3 were found to localize in the nucleus and physically interact with LcMYB1. The transcription levels of all these bHLHs were not coordinated with anthocyanin accumulation in different tissues and during development. However, when co-infiltrated with LcMYB1, both LcbHLH1 and LcbHLH3 enhanced anthocyanin accumulation in tobacco leaves with LcbHLH3 being the best inducer. Significant accumulation of anthocyanins in leaves transformed with the combination of LcMYB1 and LcbHLH3 were noticed, And this was associated with the up-regulation of two tobacco endogenous bHLH regulators, NtAn1a and NtAn1b, and late structural genes, like NtDFR and NtANS. Significant activity of the ANS promoter was observed in transient expression assays either with LcMYB1-LcbHLH1 or LcMYB1-LcbHLH3, while only minute activity was detected after transformation with only LcMYB1. In contrast, no activity was measured after induction with the combination of LcbHLH2 and LcMYB1. Higher DFR expression was also oberseved in paralleling with higher anthocyanins in co-transformed lines. LcbHLH1 and LcbHLH3 are essential partner of LcMYB1 in regulating the anthocyanin production in tobacco and probably also in litchi. The LcMYB1-LcbHLH complex enhanced anthocyanin accumulation may associate with activating the transcription of DFR and ANS.

  1. Brain Basics

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    Full Text Available ... to produce a specific protein. Scientists believe epigenetics play a major role in mental disorders and the ... thinking and feeling regions of the brain may play a role in disorders like schizophrenia or attention ...

  2. Brain Basics

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    Full Text Available ... specific protein. Scientists believe epigenetics play a major role in mental disorders and the effects of medications. ... feeling regions of the brain may play a role in disorders like schizophrenia or attention deficit hyperactivity ...

  3. Brain Basics

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    Full Text Available ... copying process is imperfect, leading to a gene mutation that causes the gene to code for a slightly different protein. Some mutations are harmless, some can be helpful, and others ...

  4. Analysis of the transcriptome of Panax notoginseng root uncovers putative triterpene saponin-biosynthetic genes and genetic markers

    Directory of Open Access Journals (Sweden)

    Luo Hongmei

    2011-12-01

    Full Text Available Abstract Background Panax notoginseng (Burk F.H. Chen is important medicinal plant of the Araliacease family. Triterpene saponins are the bioactive constituents in P. notoginseng. However, available genomic information regarding this plant is limited. Moreover, details of triterpene saponin biosynthesis in the Panax species are largely unknown. Results Using the 454 pyrosequencing technology, a one-quarter GS FLX titanium run resulted in 188,185 reads with an average length of 410 bases for P. notoginseng root. These reads were processed and assembled by 454 GS De Novo Assembler software into 30,852 unique sequences. A total of 70.2% of unique sequences were annotated by Basic Local Alignment Search Tool (BLAST similarity searches against public sequence databases. The Kyoto Encyclopedia of Genes and Genomes (KEGG assignment discovered 41 unique sequences representing 11 genes involved in triterpene saponin backbone biosynthesis in the 454-EST dataset. In particular, the transcript encoding dammarenediol synthase (DS, which is the first committed enzyme in the biosynthetic pathway of major triterpene saponins, is highly expressed in the root of four-year-old P. notoginseng. It is worth emphasizing that the candidate cytochrome P450 (Pn02132 and Pn00158 and UDP-glycosyltransferase (Pn00082 gene most likely to be involved in hydroxylation or glycosylation of aglycones for triterpene saponin biosynthesis were discovered from 174 cytochrome P450s and 242 glycosyltransferases by phylogenetic analysis, respectively. Putative transcription factors were detected in 906 unique sequences, including Myb, homeobox, WRKY, basic helix-loop-helix (bHLH, and other family proteins. Additionally, a total of 2,772 simple sequence repeat (SSR were identified from 2,361 unique sequences, of which, di-nucleotide motifs were the most abundant motif. Conclusion This study is the first to present a large-scale EST dataset for P. notoginseng root acquired by next

  5. Prognostic Significance of the Lymphoblastic Leukemia-Derived Sequence 1 (LYL1 Gene Expression in Egyptian Patients with Acute Myeloid Leukemia

    Directory of Open Access Journals (Sweden)

    Nadia El Menshawy

    2014-06-01

    Full Text Available OBJECTIVE: Aberrant activation of transcription factor genes is the most frequent target of genetic alteration in lymphoid malignancies. The lymphoblastic leukemia-derived sequence 1 (LYL1 gene, which encodes a basic helix-loop helix, was first identified with human T-cell acute leukemia. Recent studies suggest its involvement in myeloid malignancies. We aimed to study the expression percent of oncogene LYL1 in primary and secondary high-risk myeloid leukemia and the impact on prognostic significance in those patients. METHODS: Using quantitative real-time polymerase chain reaction for detection of LYL1 oncogenes, our study was carried out on 39 myeloid leukemia patients including de novo cases, myelodysplastic syndrome (MDS with transformation, and chronic myelogenous leukemia (CML in accelerated and blast crisis, in addition to 10 healthy individuals as the reference control. RESULTS: LYL1 expression was increased at least 2 times compared to the controls. The highest expression of this transcription factor was observed in the MDS cases transformed to acute leukemia at 7.3±3.1, p=0.0011. LYL1 expression was found in 68.2%, 75%, and 77.8% of cases of acute myeloid leukemia, CML crisis, and MDS, respectively. Significant correlation of LYL1 overexpression with some subtypes of French-American-British classification was found. There was, for the first time, significant correlation between the blood count at diagnosis and LYL1 expression (p=0.023, 0.002, and 0.031 for white blood cells, hemoglobin, and platelets, respectively. The rate of complete remission was lower with very high levels of LYL1 expression and the risk of relapse increased with higher levels of LYL1 expression, suggesting an unfavorable prognosis for cases with enhanced expression. CONCLUSION: Overexpression of LYL1 is highly associated with acute myeloid leukemia and shows more expression in MDS with unfavorable prognosis in response to induction chemotherapy. These

  6. Basic electronics

    CERN Document Server

    Tayal, DC

    2010-01-01

    The second edition of this book incorporates the comments and suggestions of my friends and students who have critically studied the first edition. In this edition the changes and additions have been made and subject matter has been rearranged at some places. The purpose of this text is to provide a comprehensive and up-to-date study of the principles of operation of solid state devices, their basic circuits and application of these circuits to various electronic systems, so that it can serve as a standard text not only for universities and colleges but also for technical institutes. This book

  7. Basic principles

    International Nuclear Information System (INIS)

    Wilson, P.D.

    1996-01-01

    Some basic explanations are given of the principles underlying the nuclear fuel cycle, starting with the physics of atomic and nuclear structure and continuing with nuclear energy and reactors, fuel and waste management and finally a discussion of economics and the future. An important aspect of the fuel cycle concerns the possibility of ''closing the back end'' i.e. reprocessing the waste or unused fuel in order to re-use it in reactors of various kinds. The alternative, the ''oncethrough'' cycle, discards the discharged fuel completely. An interim measure involves the prolonged storage of highly radioactive waste fuel. (UK)

  8. Detect changes in protein structure of carinata meal during rumen fermentation in relation to basic chemical profile and comparison with canola meal using ATR-FT/IR molecular spectroscopy with chemometrics

    Science.gov (United States)

    Xin, Hangshu; Yu, Peiqiang

    2013-08-01

    As far as we know, no study has been carried out on whether protein structure changes in the feed during rumen fermentation from other research team. This study was conducted to characterize protein structure spectral changes in carinata meal during ruminal fermentation using Fourier transform infrared spectroscopy (FT/IR) technique with ATR. The objectives were to find out whether (1) protein internal structure (in terms of protein amide profile and protein secondary structure profile) changed after in situ ruminal fermentation at 0, 12, 24 and 48 h in carinata meal and conventional canola meal was used as a reference; (2) there was any correlation between protein spectral parameters and basic chemical profile in in situ rumen residue samples; and (3) the protein structural chemical make-up of carinata meal differed from canola meal during 48 h rumen incubation. The results showed that protein structure features in both carinata meal and canola meal were altered as incubation time increased (P canola meal, suggesting some relationship in structural make-up exhibited between them within protein region during 48 h rumen fermentation. Further studies are still needed to investigate detailed information on structural changes in protein of various feedstuffs in order to fully and deeply understand protein degradation during rumen fermentation on both metabolic basis and molecular biological basis.

  9. Transcriptomic Analysis of the Underground Renewal Buds during Dormancy Transition and Release in ‘Hangbaishao’ Peony (Paeonia lactiflora)

    Science.gov (United States)

    Zhang, Jiaping; Wang, Guanqun; Li, Xin; Xia, Yiping

    2015-01-01

    Paeonia lactiflora is one of the most famous species of herbaceous peonies with gorgeous flowers. Bud dormancy is a crucial developmental process that allows P. lactiflora to survive unfavorable environmental conditions. However, little information is available on the molecular mechanism of the bud dormancy in P. lactiflora. We performed de novo transcriptome sequencing using the Illumina RNA sequencing platform for the underground renewal buds of P. lactiflora ‘Hangbaishao’ to study the molecular mechanism underlying its bud dormancy transition (the period from endodormancy to ecodormancy) and release (the period from ecodormancy to bud elongation and sprouting). Approximately 300 million high-quality clean reads were generated and assembled into 207,827 (mean length = 828 bp) and 51,481 (mean length = 1250 bp) unigenes using two assembly methods named “Trinity” and “Trinity+PRICE”, respectively. Based on the data obtained by the latter method, 32,316 unigenes were annotated by BLAST against various databases. Approximately 1,251 putative transcription factors were obtained, of which the largest number of unique transcripts belonged to the basic helix-loop-helix protein (bHLH) transcription factor family, and five of the top ten highly expressed transcripts were annotated as dehydrin (DHN). A total of 17,705 simple sequence repeat (SSR) motifs distributed in 13,797 sequences were obtained. The budbreak morphology, levels of indole-3-acetic acid (IAA) and abscisic acid (ABA), and activities of guaiacol peroxidase (POD) and catalase (CAT) were observed. The expression of 20 interested unigenes, which annotated as DHN, heat shock protein (HSP), histone, late elongated hypocotyl (LHY), and phytochrome (PHY), and so on, were also analyzed. These studies were based on morphological, physiological, biochemical, and molecular levels and provide comprehensive insight into the mechanism of dormancy transition and release in P. lactiflora. Transcriptome dataset

  10. Transcriptomic analysis of the underground renewal buds during dormancy transition and release in 'Hangbaishao' peony (Paeonia lactiflora.

    Directory of Open Access Journals (Sweden)

    Jiaping Zhang

    Full Text Available Paeonia lactiflora is one of the most famous species of herbaceous peonies with gorgeous flowers. Bud dormancy is a crucial developmental process that allows P. lactiflora to survive unfavorable environmental conditions. However, little information is available on the molecular mechanism of the bud dormancy in P. lactiflora. We performed de novo transcriptome sequencing using the Illumina RNA sequencing platform for the underground renewal buds of P. lactiflora 'Hangbaishao' to study the molecular mechanism underlying its bud dormancy transition (the period from endodormancy to ecodormancy and release (the period from ecodormancy to bud elongation and sprouting. Approximately 300 million high-quality clean reads were generated and assembled into 207,827 (mean length = 828 bp and 51,481 (mean length = 1250 bp unigenes using two assembly methods named "Trinity" and "Trinity+PRICE", respectively. Based on the data obtained by the latter method, 32,316 unigenes were annotated by BLAST against various databases. Approximately 1,251 putative transcription factors were obtained, of which the largest number of unique transcripts belonged to the basic helix-loop-helix protein (bHLH transcription factor family, and five of the top ten highly expressed transcripts were annotated as dehydrin (DHN. A total of 17,705 simple sequence repeat (SSR motifs distributed in 13,797 sequences were obtained. The budbreak morphology, levels of indole-3-acetic acid (IAA and abscisic acid (ABA, and activities of guaiacol peroxidase (POD and catalase (CAT were observed. The expression of 20 interested unigenes, which annotated as DHN, heat shock protein (HSP, histone, late elongated hypocotyl (LHY, and phytochrome (PHY, and so on, were also analyzed. These studies were based on morphological, physiological, biochemical, and molecular levels and provide comprehensive insight into the mechanism of dormancy transition and release in P. lactiflora. Transcriptome dataset can be

  11. 4-Hydroxy estradiol but not 2-hydroxy estradiol induces expression of hypoxia-inducible factor 1α and vascular endothelial growth factor A through phosphatidylinositol 3-kinase/Akt/FRAP pathway in OVCAR-3 and A2780-CP70 human ovarian carcinoma cells

    International Nuclear Information System (INIS)

    Gao Ning; Nester, Rebecca A.; Sarkar, Mohamadi A.

    2004-01-01

    Hypoxia-inducible factor 1 (HIF-1) is a heterodimeric basic helix-loop-helix transcription factor composed of HIF-1α and HIF-1β subunits. HIF-1 expression is induced by hypoxia, growth factors, and activation of oncogenes. HIF-1 activates downstream target genes such as vascular endothelial growth factor A (VEGF-A), which plays an important role in tumor progression and angiogenesis. Estrogen exposure is considered to be the major risk factor for ovarian cancer. Estradiol (E2) is usually metabolized by CYP1A1/1A2 and CYP3A4 to the 2-hydroxy estradiol (2-OHE2) and 4-hydroxy estradiol (4-OHE2) in human liver. Many reports have suggested that the formation of 4-OHE2 is important for mammary carcinogenesis. However, the formation of 2-OHE2 may play an important role in exhibiting anticarcinogenic effects. In the present study, we have demonstrated that one of the catechol estrogen metabolites of E2, 4-OHE2, induces HIF-1α and VEGF-A expression at protein level in two human ovarian cancer cell lines, OVCAR-3 and A2780-CP70 cells, in dose- and time-dependent manners, whereas the other catechol estrogen metabolite of E2, 2-OHE2, does not alter HIF-1α and VEGF-A expression. To explore the mechanism of 4-OHE2-induced HIF-1α and VEGF-A expression, we studied whether phosphatidylinositol 3-kinase (PI3K) or mitogen-activated protein kinase (MAPK) signaling pathways are involved in 4-OHE2-induced HIF-1α and VEGF-A expression. Our findings indicate that PI3K inhibitors, LY294002 and wortmannin, inhibited HIF-1α and VEGF-A expression, whereas MAPK inhibitor, PD98059, did not alter HIF-1α and VEGF-A expression induced by 4-OHE2. 4-OHE2, but not 2-OHE2, also induced Akt phosphorylation at Ser473 in dose- and time-dependent manners, and LY294002 and wortmannin inhibited Akt phosphorylation at Ser473 induced by 4-OHE2. Our results also indicated that the mTOR/FRAP inhibitor, rapamycin, inhibited 4-OHE2-induced HIF-1α and VEGF-A expression. These results suggest that the PI3K

  12. The effect of cytosolic extract of Alternaria aternata fungus on Monocyte-derived dendritic cell maturation and T-lymphocyte polarization in the presence of myelin basic protein

    Directory of Open Access Journals (Sweden)

    Loghmanni A

    2013-03-01

    Full Text Available Background: Multiple Sclerosis (MS is an autoimmune disease with impairment in function of central nervous system. Macrophages and dendritic cells play important roles in alleviating or progression of the disease. These cells can cause inflammation and damage to the myelin of nerve cells by realizing of harmful substances when these cells get matured. We studied the effect of Alternaria alternata extract on maturation of monocyte- derived dendritic cell (modc and T-cell responses in the presence of Myelin Basic Protein (MBP as a laboratory model of multiple sclerosis (MS. The purpose of this study is suitable dendritic cells production for usage in MS immunotherapy.Methods: For this study plastic adherent monocytes were cultured with granulocyte/ macrophage- colony stimulating factor (GM-CSF and interleukin -4 for converting these cells to modc and pulsed with MBP and matured in the presence of monocyte-conditioned medium (MCM in control group and MCM + Alternaria alternata extract in treatment groups. Anti-CD14, anti-CD83, anti-human leukocyte antigen-DR (anti HLA-DR monoclonal antibody were carried out for phenotyping. Autologos T cell responses and cytokine production were evaluated.Results: The results showed that the expression of CD14 decreased and CD83, HLA-DR increased in treatment groups in comparison with control groups. The production amount of IL-10 overcame IL-12 and in T cell the production of cytokines, IL-17 and Interferon-γ (IFN-γ decreased and IL-4 was increased (P<0.05. These effects escalated with increasing of dosage from 50 to 100 (mg/ml (P<0.001.Conclusion: Alternaria alternata extract can cause maturation of MBP-pulsed modc and skewing of T- lymphocyte toward Th2 and thereby can evolve into a new strategy in immunotherapy of MS.

  13. Distinct accessory cell requirements define two types of rat T cell hybridomas specific for unique determinants in the encephalitogenic 68-86 region of myelin basic protein

    International Nuclear Information System (INIS)

    Mannie, M.D.; Paterson, P.Y.; Thomas, D.W.; Nairn, R.

    1990-01-01

    Six clonotypically unique T cell hybridomas from Lewis rats were used to study accessory cell activities required for class II MHC restricted T cell responses to the 68-86 encephalitogenic sequence of myelin basic protein (MBP). T cell hybrids which were cultured with GP68-86 68-86 sequence of guinea pig MBP (GPMBP) and naive splenocytes (SPL) were induced to produce IL-2 as measured by the CTLL indicator cell line. The hybrids were categorized into two subsets (designated THYB-1 and THYB-2), because two distinct subset-specific pathways of communication between accessory cells and T cells were involved in GPMBP-induced IL-2 production. These pathways were distinguished by the following six observations. First, when the duration of a pulse of SPL with GPMBP was lengthened from 1 to 4 h, these SPL lost their ability to induce IL-2 production by THYB-2 hybrids yet nevertheless retained full stimulatory activity for THYB-1 hybrids. Second, paraformaldehyde fixation of GPMBP-pulsed SPL abrogated an activity necessary for Ag-induced IL-2 production by THYB-2 hybrids. These fixed SPL were nevertheless able to stimulate THYB-1 hybrids, albeit to a lesser extent than viable unfixed SPL. Third, the addition of either cycloheximide, cytochalasin B, or 2-deoxyglucose to an Ag pulse of SPL with GPMBP dramatically inhibited the subsequent responses of THYB-2 hybrids yet had little or no effect upon the reactivity of THYB-1 hybrids. Fourth, thymocytes lacked necessary activities for GPMBP evoked IL-2 production by THYB-2 hybrids yet strongly promoted THYB-1 hybrid responses. Fifth, exposure of SPL to as little as 500 rad of gamma-irradiation markedly attenuated THYB-2 hybrid response to GPMBP but did not affect THYB-1 responses. Sixth, anti-GPMBP responses by THYB-2 hybrids were observed only in the presence of both radioresistant adherent SPL and a distinct population of radiosensitive nonadherent SPL

  14. A Cyclic Altered Peptide Analogue Based on Myelin Basic Protein 87–99 Provides Lasting Prophylactic and Therapeutic Protection Against Acute Experimental Autoimmune Encephalomyelitis

    Directory of Open Access Journals (Sweden)

    Mary Emmanouil

    2018-01-01

    Full Text Available In this report, amide-linked cyclic peptide analogues of the 87–99 myelin basic protein (MBP epitope, a candidate autoantigen in multiple sclerosis (MS, are tested for therapeutic efficacy in experimental autoimmune encephalomyelitis (EAE. Cyclic altered peptide analogues of MBP87–99 with substitutions at positions 91 and/or 96 were tested for protective effects when administered using prophylactic or early therapeutic protocols in MBP72–85-induced EAE in Lewis rats. The Lys91 and Pro96 of MBP87–99 are crucial T-cell receptor (TCR anchors and participate in the formation of trimolecular complex between the TCR-antigen (peptide-MHC (major histocompability complex for the stimulation of encephalitogenic T cells that are necessary for EAE induction and are implicated in MS. The cyclic peptides were synthesized using Solid Phase Peptide Synthesis (SPPS applied on the 9-fluorenylmethyloxycarboxyl/tert-butyl Fmoc/tBu methodology and combined with the 2-chlorotrityl chloride resin (CLTR-Cl. Cyclo(91–99[Ala96]MBP87–99, cyclo(87–99[Ala91,96]MBP87–99 and cyclo(87–99[Arg91, Ala96]MBP87–99, but not wild-type linear MBP87–99, strongly inhibited MBP72–85-induced EAE in Lewis rats when administered using prophylactic and early therapeutic vaccination protocols. In particular, cyclo(87–99[Arg91, Ala96]MBP87–99 was highly effective in preventing the onset and development of clinical symptoms and spinal cord pathology and providing lasting protection against EAE induction.

  15. Differential expression of neurotrophic factors and inflammatory cytokines by myelin basic protein-specific and other recruited T cells infiltrating the central nervous system during experimental autoimmune encephalomyelitis.

    Science.gov (United States)

    Muhallab, S; Lundberg, C; Gielen, A W; Lidman, O; Svenningsson, A; Piehl, F; Olsson, T

    2002-03-01

    Recent evidence suggests that autoimmune reactions in the central nervous system (CNS) not only have detrimental consequences but can also be neuroprotective, and that this effect is mediated by the expression of neuronal growth factors by infiltrating leucocytes. Here we dissect these two phenomena in guinea pig myelin basic protein peptide (gpMBP 63-88)-induced experimental autoimmune encephalomyelitis (EAE) in the Lewis rat. Real-time TaqMan polymerase chain reaction (PCR) was used to measure mRNA for the nerve growth factors, brain-derived neurotrophic factor (BDNF) and neurotrophin (NT)-3. As reference, the well-known proinflammatory mediator molecules interferon (IFN)-gamma and tumour necrosis factor (TNF)-alpha were quantified. In whole lumbar cord tissue, both the nerve growth factors and the proinflammatory cytokines, IFN-gamma and TNF-alpha, displayed similar expression patterns, peaking at the height of the disease. Among the infiltrating inflammatory cells isolated and sorted from the CNS, alphabeta+/T-cell receptor (TCR)BV8S2+, but not alphabeta+/TCRBV8S2-, recognized the encephalitogenic MBP peptide. Interestingly, these two populations displayed contrasting expression patterns of nerve growth factors and proinflammatory cytokines with higher inflammatory cytokine mRNA levels in alphabeta+/TCRBV8S2+ cells at all time intervals, whereas the levels of BDNF and NT3 were higher in alphabeta+/TCRBV8S2- cells. We conclude that a potentially important neuroprotective facet of CNS inflammation dominantly prevails within other non-MBP peptide-specific lymphoid cells and that there are independent regulatory mechanisms for neurotrophin and inflammatory cytokine expression during EAE.

  16. The conserved basic residues and the charged amino acid residues at the α-helix of the zinc finger motif regulate the nuclear transport activity of triple C2H2 zinc finger proteins

    Science.gov (United States)

    Lin, Chih-Ying

    2018-01-01

    Zinc finger (ZF) motifs on proteins are frequently recognized as a structure for DNA binding. Accumulated reports indicate that ZF motifs contain nuclear localization signal (NLS) to facilitate the transport of ZF proteins into nucleus. We investigated the critical factors that facilitate the nuclear transport of triple C2H2 ZF proteins. Three conserved basic residues (hot spots) were identified among the ZF sequences of triple C2H2 ZF proteins that reportedly have NLS function. Additional basic residues can be found on the α-helix of the ZFs. Using the ZF domain (ZFD) of Egr-1 as a template, various mutants were constructed and expressed in cells. The nuclear transport activity of various mutants was estimated by analyzing the proportion of protein localized in the nucleus. Mutation at any hot spot of the Egr-1 ZFs reduced the nuclear transport activity. Changes of the basic residues at the α-helical region of the second ZF (ZF2) of the Egr-1 ZFD abolished the NLS activity. However, this activity can be restored by substituting the acidic residues at the homologous positions of ZF1 or ZF3 with basic residues. The restored activity dropped again when the hot spots at ZF1 or the basic residues in the α-helix of ZF3 were mutated. The variations in nuclear transport activity are linked directly to the binding activity of the ZF proteins with importins. This study was extended to other triple C2H2 ZF proteins. SP1 and KLF families, similar to Egr-1, have charged amino acid residues at the second (α2) and the third (α3) positions of the α-helix. Replacing the amino acids at α2 and α3 with acidic residues reduced the NLS activity of the SP1 and KLF6 ZFD. The reduced activity can be restored by substituting the α3 with histidine at any SP1 and KLF6 ZFD. The results show again the interchangeable role of ZFs and charge residues in the α-helix in regulating the NLS activity of triple C2H2 ZF proteins. PMID:29381770

  17. The conserved basic residues and the charged amino acid residues at the α-helix of the zinc finger motif regulate the nuclear transport activity of triple C2H2 zinc finger proteins.

    Science.gov (United States)

    Lin, Chih-Ying; Lin, Lih-Yuan

    2018-01-01

    Zinc finger (ZF) motifs on proteins are frequently recognized as a structure for DNA binding. Accumulated reports indicate that ZF motifs contain nuclear localization signal (NLS) to facilitate the transport of ZF proteins into nucleus. We investigated the critical factors that facilitate the nuclear transport of triple C2H2 ZF proteins. Three conserved basic residues (hot spots) were identified among the ZF sequences of triple C2H2 ZF proteins that reportedly have NLS function. Additional basic residues can be found on the α-helix of the ZFs. Using the ZF domain (ZFD) of Egr-1 as a template, various mutants were constructed and expressed in cells. The nuclear transport activity of various mutants was estimated by analyzing the proportion of protein localized in the nucleus. Mutation at any hot spot of the Egr-1 ZFs reduced the nuclear transport activity. Changes of the basic residues at the α-helical region of the second ZF (ZF2) of the Egr-1 ZFD abolished the NLS activity. However, this activity can be restored by substituting the acidic residues at the homologous positions of ZF1 or ZF3 with basic residues. The restored activity dropped again when the hot spots at ZF1 or the basic residues in the α-helix of ZF3 were mutated. The variations in nuclear transport activity are linked directly to the binding activity of the ZF proteins with importins. This study was extended to other triple C2H2 ZF proteins. SP1 and KLF families, similar to Egr-1, have charged amino acid residues at the second (α2) and the third (α3) positions of the α-helix. Replacing the amino acids at α2 and α3 with acidic residues reduced the NLS activity of the SP1 and KLF6 ZFD. The reduced activity can be restored by substituting the α3 with histidine at any SP1 and KLF6 ZFD. The results show again the interchangeable role of ZFs and charge residues in the α-helix in regulating the NLS activity of triple C2H2 ZF proteins.

  18. Effects of overexpression of a bHLH transcription factor on biomass and lipid production in Nannochloropsis salina.

    Science.gov (United States)

    Kang, Nam Kyu; Jeon, Seungjib; Kwon, Sohee; Koh, Hyun Gi; Shin, Sung-Eun; Lee, Bongsoo; Choi, Gang-Guk; Yang, Ji-Won; Jeong, Byeong-Ryool; Chang, Yong Keun

    2015-01-01

    Microalgae are considered promising alternative energy sources because they consume CO2 and accumulate large amounts of lipids that can be used as biofuel. Nannochloropsis is a particularly promising microalga due to its high growth rate and lipid content, and the availability of genomic information. Transcription factors (TFs) are global regulators of biological pathways by up- or down-regulation of related genes. Among these, basic helix-loop-helix (bHLH) TFs regulate growth, development, and stress responses in plants and animals, and have been identified in microalgae. We identified two bHLH TFs in the genome of N. salina CCMP1776, NsbHLH1, and NsbHLH2, and characterized functions of NsbHLH2 that may be involved in growth and nutrient uptake. We obtained NsbHLH2 overexpressing transformants of N. salina CCMP1776 by particle bombardment and confirmed that these were stable transformants. Quantitative real-time polymerase chain reaction (qRT-PCR) and Western blotting using antibodies against the FLAG tag that was attached at the end of the coding sequence confirmed the expression of the NsbHLH2 protein under various culture conditions. The qRT-PCR results also indicated that the endogenous and transgenic expression of NsbHLH2 was reduced under stressed conditions. Overexpression of NsbHLH2 led to increased growth rate in the early growth period, and concomitantly higher nutrient uptake, than wild type (WT). These enhanced growth and nutrient uptake resulted in increased productivities of biomass and FAME. For example, one of the transformants, NsbHLH2 3-6, showed increased biomass productivity by 36 % under the normal condition, and FAME productivity by 33 % under nitrogen limitation condition. Conclusively, the improved growth in the transformants can be associated with the enhanced nutrient uptake. We are currently assessing their potential for scale-up cultivation with positive outcomes. Overexpression of NsbHLH2 led to enhanced growth rate and nutrient

  19. Hypoxia inducible BHLHB2 is a novel and independent prognostic marker in pancreatic ductal adenocarcinoma

    International Nuclear Information System (INIS)

    Wang, Weibin; Reiser-Erkan, Carolin; Michalski, Christoph W.; Raggi, Matthias C.; Quan, Liao; Yupei, Zhao; Friess, Helmut; Erkan, Mert; Kleeff, Joerg

    2010-01-01

    Research highlights: → The expression and function of BHLHB2 (DEC1/SHARP2) in pancreatic cancer is unknown. → Hypoxia and serum starvation induces BHLHB2 expression in pancreatic ductal adenocarcinoma. → BHLHB2 inhibition in pancreatic cancer cell line SU86.86 increases ED50 of gemcitabine 2.8-fold. → BHLHB2 is an independent prognostic factor in multivariable cox analysis with a hazard ratio of 2:4. -- Abstract: Aims: The cyclic adenosine monophosphate-inducible basic helix-loop-helix (bHLH) domain containing class-B2 transcriptional factor BHLHB2 is differentially expressed in a number of human malignancies. In the present study, the expression, regulation, functions and prognostic impact of BHLHB2 in pancreatic cancer were investigated. Methods: Expression analyses were carried out in tissues of the normal pancreas (n = 10) and pancreatic ductal adenocarcinoma (n = 77) as well as in eight pancreatic cancer cell lines using quantitative RT-PCR, semiquantitative immunohistochemistry, and immunoblot analyses. In vitro functional experiments were conducted using siRNA transfection, hypoxia, serum starvation, apoptosis induction with gemcitabine and actinomycin-D, and invasion assays. Survival analysis was performed using the Kaplan-Meier method. Prognostic factors were determined in a multivariable analysis using a Cox proportional hazards model. Results: BHLHB2 mRNA and protein expressions were strongly induced by hypoxia and by serum starvation in pancreatic cancer cell lines. BHLHB2 silencing with RNAi had no significant effects on growth and invasion but increased apoptosis resistance against gemcitabine by reducing caspace-3 cleavage. In BHLHB2 silenced cells the ED50 of gemcitabine increased from 13.95 ± 1.353 to 38.70 ± 5.262 nM (p < 0.05). Ex vivo, the weak/absent nuclear staining in normal pancreatic ducts and acinar cells was replaced by moderate to strong nuclear/cytoplasmic staining in PanIN lesions and pancreatic cancer cells. Patients with

  20. The function of OsbHLH068 is partially redundant with its homolog, AtbHLH112, in the regulation of the salt stress response but has opposite functions to control flowering in Arabidopsis.

    Science.gov (United States)

    Chen, Hung-Chi; Hsieh-Feng, Vicki; Liao, Pei-Chun; Cheng, Wan-Hsing; Liu, Li-Yu; Yang, Yun-Wei; Lai, Ming-Hsin; Chang, Men-Chi

    2017-07-01

    The homologous genes OsbHLH068 and AtbHLH112 have partially redundant functions in the regulation of the salt stress response but opposite functions to control flowering in Arabidopsis. The transcription factor (TF) basic/Helix-Loop-Helix (bHLH) is important for plant growth, development, and stress responses. OsbHLH068, which is a homologous gene of AtbHLH112 that is up-regulated under drought and salt stresses, as indicated by previous microarray data analysis. However, the intrinsic function of OsbHLH068 remains unknown. In the present study, we characterized the function and compared the role of OsbHLH068 with that of its homolog, AtbHLH112. Histochemical GUS staining indicated that OsbHLH068 and AtbHLH112 share a similar expression pattern in transgenic Arabidopsis during the juvenile-to-adult phase transition. Heterologous overexpression of OsbHLH068 in Arabidopsis delays seed germination, decreases salt-induced H 2 O 2 accumulation, and promotes root elongation, whereas AtbHLH112 knock-out mutant displays an opposite phenotype. Both OsbHLH068-overexpressing transgenic Arabidopsis seedlings and the Atbhlh112 mutant display a late-flowering phenotype. Moreover, the expression of OsbHLH068-GFP driven by an AtbHLH112 promoter can compensate for the germination deficiency in the Atbhlh112 mutant, but the delayed-flowering phenotype tends to be more severe. Further analysis by microarray and qPCR indicated that the expression of FT is down-regulated in both OsbHLH068-overexpressing Arabidopsis plants and Atbhlh112 mutant plants, whereas SOC1 but not FT is highly expressed in AtbHLH112-overexpressing Arabidopsis plants. A comparative transcriptomic analysis also showed that several stress-responsive genes, such as AtERF15 and AtPUB23, were affected in both OsbHLH068- and AtbHLH112-overexpressing transgenic Arabidopsis plants. Thus, we propose that OsbHLH068 and AtbHLH112 share partially redundant functions in the regulation of abiotic stress responses but have

  1. Hypoxia inducible BHLHB2 is a novel and independent prognostic marker in pancreatic ductal adenocarcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Weibin; Reiser-Erkan, Carolin; Michalski, Christoph W.; Raggi, Matthias C. [Department of Surgery, Technische Universitaet Muenchen, Munich (Germany); Quan, Liao; Yupei, Zhao [Department of General Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Science, Peking (China); Friess, Helmut [Department of Surgery, Technische Universitaet Muenchen, Munich (Germany); Erkan, Mert, E-mail: erkan@chir.med.tu-muenchen.de [Department of Surgery, Technische Universitaet Muenchen, Munich (Germany); Kleeff, Joerg [Department of Surgery, Technische Universitaet Muenchen, Munich (Germany)

    2010-10-22

    Research highlights: {yields} The expression and function of BHLHB2 (DEC1/SHARP2) in pancreatic cancer is unknown. {yields} Hypoxia and serum starvation induces BHLHB2 expression in pancreatic ductal adenocarcinoma. {yields} BHLHB2 inhibition in pancreatic cancer cell line SU86.86 increases ED50 of gemcitabine 2.8-fold. {yields} BHLHB2 is an independent prognostic factor in multivariable cox analysis with a hazard ratio of 2:4. -- Abstract: Aims: The cyclic adenosine monophosphate-inducible basic helix-loop-helix (bHLH) domain containing class-B2 transcriptional factor BHLHB2 is differentially expressed in a number of human malignancies. In the present study, the expression, regulation, functions and prognostic impact of BHLHB2 in pancreatic cancer were investigated. Methods: Expression analyses were carried out in tissues of the normal pancreas (n = 10) and pancreatic ductal adenocarcinoma (n = 77) as well as in eight pancreatic cancer cell lines using quantitative RT-PCR, semiquantitative immunohistochemistry, and immunoblot analyses. In vitro functional experiments were conducted using siRNA transfection, hypoxia, serum starvation, apoptosis induction with gemcitabine and actinomycin-D, and invasion assays. Survival analysis was performed using the Kaplan-Meier method. Prognostic factors were determined in a multivariable analysis using a Cox proportional hazards model. Results: BHLHB2 mRNA and protein expressions were strongly induced by hypoxia and by serum starvation in pancreatic cancer cell lines. BHLHB2 silencing with RNAi had no significant effects on growth and invasion but increased apoptosis resistance against gemcitabine by reducing caspace-3 cleavage. In BHLHB2 silenced cells the ED50 of gemcitabine increased from 13.95 {+-} 1.353 to 38.70 {+-} 5.262 nM (p < 0.05). Ex vivo, the weak/absent nuclear staining in normal pancreatic ducts and acinar cells was replaced by moderate to strong nuclear/cytoplasmic staining in PanIN lesions and pancreatic cancer

  2. Promoted neuronal differentiation after activation of alpha4/beta2 nicotinic acetylcholine receptors in undifferentiated neural progenitors.

    Directory of Open Access Journals (Sweden)

    Takeshi Takarada

    Full Text Available BACKGROUND: Neural progenitor is a generic term used for undifferentiated cell populations of neural stem, neuronal progenitor and glial progenitor cells with abilities for proliferation and differentiation. We have shown functional expression of ionotropic N-methyl-D-aspartate (NMDA and gamma-aminobutyrate type-A receptors endowed to positively and negatively regulate subsequent neuronal differentiation in undifferentiated neural progenitors, respectively. In this study, we attempted to evaluate the possible functional expression of nicotinic acetylcholine receptor (nAChR by undifferentiated neural progenitors prepared from neocortex of embryonic rodent brains. METHODOLOGY/PRINCIPAL FINDINGS: Reverse transcription polymerase chain reaction analysis revealed mRNA expression of particular nAChR subunits in undifferentiated rat and mouse progenitors prepared before and after the culture with epidermal growth factor under floating conditions. Sustained exposure to nicotine significantly inhibited the formation of neurospheres composed of clustered proliferating cells and 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide reduction activity at a concentration range of 1 µM to 1 mM without affecting cell survival. In these rodent progenitors previously exposed to nicotine, marked promotion was invariably seen for subsequent differentiation into cells immunoreactive for a neuronal marker protein following the culture of dispersed cells under adherent conditions. Both effects of nicotine were significantly prevented by the heteromeric α4β2 nAChR subtype antagonists dihydro-β-erythroidine and 4-(5-ethoxy-3-pyridinyl-N-methyl-(3E-3-buten-1-amine, but not by the homomeric α7 nAChR subtype antagonist methyllycaconitine, in murine progenitors. Sustained exposure to nicotine preferentially increased the expression of Math1 among different basic helix-loop-helix proneural genes examined. In undifferentiated progenitors from embryonic mice

  3. Multiple upstream modules regulate zebrafish myf5 expression

    Directory of Open Access Journals (Sweden)

    Weng Chih-Wei

    2007-01-01

    Full Text Available Abstract Background Myf5 is one member of the basic helix-loop-helix family of transcription factors, and it functions as a myogenic factor that is important for the specification and differentiation of muscle cells. The expression of myf5 is somite- and stage-dependent during embryogenesis through a delicate regulation. However, this complex regulatory mechanism of myf5 is not clearly understood. Results We isolated a 156-kb bacterial artificial chromosome clone that includes an upstream 80-kb region and a downstream 70-kb region of zebrafish myf5 and generated a transgenic line carrying this 156-kb segment fused to a green fluorescent protein (GFP reporter gene. We find strong GFP expression in the most rostral somite and in the presomitic mesoderm during segmentation stages, similar to endogenous myf5 expression. Later, the GFP signals persist in caudal somites near the tail bud but are down-regulated in the older, rostral somites. During the pharyngula period, we detect GFP signals in pectoral fin buds, dorsal rostral myotomes, hypaxial myotomes, and inferior oblique and superior oblique muscles, a pattern that also corresponds well with endogenous myf5 transcripts. To characterize the specific upstream cis-elements that regulate this complex and dynamic expression pattern, we also generated several transgenic lines that harbor various lengths within the upstream 80-kb segment. We find that (1 the -80 kb/-9977 segment contains a fin and cranial muscle element and a notochord repressor; (2 the -9977/-6213 segment contains a strong repressive element that does not include the notochord-specific repressor; (3 the -6212/-2938 segment contains tissue-specific elements for bone and spinal cord; (4 the -2937/-291 segment contains an eye enhancer, and the -2937/-2457 segment is required for notochord and myocyte expression; and (5 the -290/-1 segment is responsible for basal transcription in somites and the presomitic mesoderm. Conclusion We suggest

  4. SlbHLH068 interacts with FER to regulate the iron-deficiency response in tomato.

    Science.gov (United States)

    Du, Juan; Huang, Zongan; Wang, Biao; Sun, Hua; Chen, Chunlin; Ling, Hong-Qing; Wu, Huilan

    2015-07-01

    Iron is an essential micronutrient for all organisms and its uptake, translocation, distribution and utilization are regulated in a complex manner in plants. FER, isolated from tomato (Solanum lycopersicum), was the first transcription factor involved in the iron homeostasis of higher plants to be identified. A FER defect in the T3238fer mutant drastically downregulates the expression of iron uptake genes, such as ferric-chelate reductase 1 (LeFRO1) and iron-regulated transporter 1 (LeIRT1); however, the molecular mechanism by which FER regulates genes downstream remains unknown. The aim of this work was therefore to identify the gene that interacts with FER to regulate the iron-deficiency response in tomato. The homologue of the Arabidopsis Ib subgroup of the basic helix-loop-helix (bHLH) proteins, SlbHLH068, was identified by using the program BLASTP against the AtbHLH39 amino acid sequence in the tomato genome. The interaction between SlbHLH068 and FER was detected using yeast two-hybrid and bimolecular fluorescence complementation (BiFC) assays. In addition, virus-induced gene silencing (VIGS) was used to generate tomato plants in which SlbHLH068 expression was downregulated. The expression of genes was analysed using northern blot hybridization and multiple RT-PCR analysis. Seedlings of wild-type and mutant plants were grown under conditions of different nutrient deficiency. SlbHLH068 is highly upregulated in roots, leaves and stems in response to iron deficiency. An interaction between SlbHLH068 and FER was demonstrated using yeast two-hybrid and BiFC assays. The heterodimer formed by FER with SlbHLH068 directly bound to the promoter of LeFRO1 and activated the expression of its reporter gene in the yeast assay. The downregulation of SlbHLH068 expression by VIGS resulted in a reduction of LeFRO1 and LeIRT1 expression and iron accumulation in leaves and roots. The results indicate that SlbHLH068, as a putative transcription factor, is involved in iron

  5. Organic cation transporter-mediated ergothioneine uptake in mouse neural progenitor cells suppresses proliferation and promotes differentiation into neurons.

    Directory of Open Access Journals (Sweden)

    Takahiro Ishimoto

    cellular proliferation via regulation of oxidative stress, and also promotes cellular differentiation by modulating the expression of basic helix-loop-helix transcription factors via an unidentified mechanism different from antioxidant action.

  6. Increased expression of bHLH transcription factor E2A (TCF3) in prostate cancer promotes proliferation and confers resistance to doxorubicin induced apoptosis

    Energy Technology Data Exchange (ETDEWEB)

    Patel, Divya [Center for Cancer Research and Therapeutics Development, Clark Atlanta University, 223 James P. Brawley Dr. SW, Atlanta, GA 30314 (United States); Chaudhary, Jaideep, E-mail: jchaudhary@cau.edu [Center for Cancer Research and Therapeutics Development, Clark Atlanta University, 223 James P. Brawley Dr. SW, Atlanta, GA 30314 (United States); Dept. of Biological Sciences, Clark Atlanta University, 223 James P. Brawley Dr. SW, Atlanta, GA 30314 (United States)

    2012-05-25

    Highlights: Black-Right-Pointing-Pointer E2A, considered as a tumor suppressor is highly expressed in prostate cancer. Black-Right-Pointing-Pointer Silencing of E2A attenuates cell proliferation and promotes apoptosis. Black-Right-Pointing-Pointer E2A regulates c-myc, Id1, Id3 and CDKN1A expression. Black-Right-Pointing-Pointer Loss of E2A promotes doxorubicin dependent apoptosis in prostate cancer cells. Black-Right-Pointing-Pointer Results suggest that E2A acts as a tumor promoter at least in prostate cancer. -- Abstract: E2A (TCF3) is a multifunctional basic helix loop helix (bHLH), transcription factor. E2A regulates transcription of target genes by homo- or heterodimerization with cell specific bHLH proteins. In general, E2A promotes cell differentiation, acts as a negative regulator of cell proliferation in normal cells and cancer cell lines and is required for normal B-cell development. Given the diverse biological pathways regulated/influenced by E2A little is known about its expression in cancer. In this study we investigated the expression of E2A in prostate cancer. Unexpectedly, E2A immuno-histochemistry demonstrated increased E2A expression in prostate cancer as compared to normal prostate. Silencing of E2A in prostate cancer cells DU145 and PC3 led to a significant reduction in proliferation due to G1 arrest that was in part mediated by increased CDKN1A(p21) and decreased Id1, Id3 and c-myc. E2A silencing in prostate cancer cell lines also resulted in increased apoptosis due to increased mitochondrial permeability and caspase 3/7 activation. Moreover, silencing of E2A increased sensitivity to doxorubicin induced apoptosis. Based on our results, we propose that E2A could be an upstream regulator of Id1 and c-Myc which are highly expressed in prostate cancer. These results for the first time demonstrate that E2A could in fact acts as a tumor promoter at least in prostate cancer.

  7. Design, synthesis and evaluation of an anthraquinone derivative conjugated to myelin basic protein immunodominant (MBP85-99) epitope: Towards selective immunosuppression.

    Science.gov (United States)

    Tapeinou, Anthi; Giannopoulou, Efstathia; Simal, Carmen; Hansen, Bjarke E; Kalofonos, Haralabos; Apostolopoulos, Vasso; Vlamis-Gardikas, Alexios; Tselios, Theodore

    2018-01-01

    Anthraquinone type compounds, especially di-substituted amino alkylamino anthraquinones have been widely studied as immunosuppressants. The anthraquinone ring is part of mitoxandrone that has been used for the treatment of multiple sclerosis (MS) and several types of tumors. A desired approach for the treatment of MS would be the immunosuppression and elimination of specific T cells that are responsible for the induction of the disease. Herein, the development of a peptide compound bearing an anthraquinone derivative with the potential to specifically destroy the encephalitogenic T cells responsible for the onset of MS is described. The compound consists of the myelin basic protein (MBP) 85-99 immunodominant epitope (MBP 85-99 ) coupled to an anthraquinone type molecule (AQ) via a disulfide (S-S) and 6 amino hexanoic acid (Ahx) residues (AQ-S-S-(Ahx) 6 MBP 85-99 ). AQ-S-S-(Ahx) 6 MBP 85-99 could bind to HLA II DRB1*-1501 antigen with reasonable affinity (IC 50 of 56 nM) The compound was localized to the nucleus of Jurkat cells (an immortalized line of human T lymphocytes) 10 min after its addition to the medium and resulted in lowered Bcl-2 levels (apoptosis). Entrance of the compound was abolished when cells were pre-treated with cisplatin, an inhibitor of thioredoxin reductase. Accordingly, levels of free thiols were elevated in the culture supernatants of Jurkat cells exposed to N-succinimidyl 3-(2-pyridyldithio) propionate coupled to (Ahx) 6 MBP 85-99 via a disulphide (SPDP-S-S-(Ahx) 6 MBP 85-99 ) but returned to normal after exposure to cisplatin. These results raise the possibility of AQ-S-S-(Ahx) 6 MBP 85-99 being used as an eliminator of encephalitogenic T cells via implication of the thioredoxin system for the generation of the toxic, thiol-containing moiety (AQ-SH). Future experiments would ideally determine whether SPDP-S-S-(Ahx) 6 MBP 85-99 could incorporate into HLA II DRB1*-1501 tetramers and neutralize encephalitogenic T cell lines sensitized to

  8. Phactr3/scapinin, a member of protein phosphatase 1 and actin regulator (phactr family, interacts with the plasma membrane via basic and hydrophobic residues in the N-terminus.

    Directory of Open Access Journals (Sweden)

    Akihiro Itoh

    Full Text Available Proteins that belong to the protein phosphatase 1 and actin regulator (phactr family are involved in cell motility and morphogenesis. However, the mechanisms that regulate the actin cytoskeleton are poorly understood. We have previously shown that phactr3, also known as scapinin, localizes to the plasma membrane, including lamellipodia and membrane ruffles. In the present study, experiments using deletion and point mutants showed that the basic and hydrophobic residues in the N-terminus play crucial roles in the localization to the plasma membrane. A BH analysis (http://helixweb.nih.gov/bhsearch is a program developed to identify membrane-binding domains that comprise basic and hydrophobic residues in membrane proteins. We applied this program to phactr3. The results of the BH plot analysis agreed with the experimentally determined region that is responsible for the localization of phactr3 to the plasma membrane. In vitro experiments showed that the N-terminal itself binds to liposomes and acidic phospholipids. In addition, we showed that the interaction with the plasma membrane via the N-terminal membrane-binding sequence is required for phactr3-induced morphological changes in Cos7 cells. The membrane-binding sequence in the N-terminus is highly conserved in all members of the phactr family. Our findings may provide a molecular basis for understanding the mechanisms that allow phactr proteins to regulate cell morphogenesis.

  9. UV-Vis spectroscopy of tyrosine side-groups in studies of protein structure. Part 1: basic principles and properties of tyrosine chromophore.

    Science.gov (United States)

    Antosiewicz, Jan M; Shugar, David

    2016-06-01

    Spectroscopic properties of tyrosine residues may be employed in structural studies of proteins. Here we discuss several different types of UV-Vis spectroscopy, like normal, difference and second-derivative UV absorption spectroscopy, fluorescence spectroscopy, linear and circular dichroism spectroscopy, and Raman spectroscopy, and corresponding optical properties of the tyrosine chromophore, phenol, which are used to study protein structure.

  10. UV?Vis spectroscopy of tyrosine side-groups in studies of protein structure. Part 1: basic principles and properties of tyrosine chromophore

    OpenAIRE

    Antosiewicz, Jan M.; Shugar, David

    2016-01-01

    Spectroscopic properties of tyrosine residues may be employed in structural studies of proteins. Here we discuss several different types of UV?Vis spectroscopy, like normal, difference and second-derivative UV absorption spectroscopy, fluorescence spectroscopy, linear and circular dichroism spectroscopy, and Raman spectroscopy, and corresponding optical properties of the tyrosine chromophore, phenol, which are used to study protein structure.

  11. Broadening Horizons and Teaching Basic Biology through Cell-Free Synthesis of Green Fluorescent Protein in a High School Laboratory Course

    Science.gov (United States)

    Albayrak, Cem; Jones, K. C.; Swartz, James R.

    2013-01-01

    Cell-free protein synthesis (CFPS) has emerged as a practical method for producing a broad variety of proteins. In addition, the direct accessibility to the reaction environment makes CFPS particularly suitable as a learning vehicle for fundamental biological concepts. Here, we describe its implementation as a teaching tool for a high school…

  12. Primary structure of a 14 kDa basic structural protein (Lm-76) from the cuticle of the migratory locust, Locusta migratoria

    DEFF Research Database (Denmark)

    Andersen, Jens S.; Andersen, S O; Højrup, P

    1993-01-01

    The complete amino acid sequence of a 14 kDa structural protein (LM-76) isolated from pharate cuticle of the locust, Locusta migratoria, was determined by Edman degradation of the intact protein and enzymatically derived peptides. Plasma desorption and electrospray mass spectrometry was used as a...

  13. Targeted toxicological screening for acidic, neutral and basic substances in postmortem and antemortem whole blood using simple protein precipitation and UPLC-HR-TOF-MS

    DEFF Research Database (Denmark)

    Telving, Rasmus; Hasselstrøm, Jørgen Bo; Andreasen, Mette Findal

    2016-01-01

    -HR-TOF-MS was achieved in one injection. This method covered basic substances, substances traditionally analyzed in negative ESI (e.g., salicylic acid), small highly polar substances such as beta- and gamma-hydroxybutyric acid (BHB and GHB, respectively) and highly non-polar substances such as amiodarone. The new method......A broad targeted screening method based on broadband collision-induced dissociation (bbCID) ultra-performance liquid chromatography high-resolution time-of-flight mass spectrometry (UPLC-HR-TOF-MS) was developed and evaluated for toxicological screening of whole blood samples. The acidic, neutral...... was performed on spiked whole blood samples and authentic postmortem and antemortem whole blood samples. For most of the basic drugs, the established cut-off limits were very low, ranging from 0.25ng/g to 50ng/g. The established cut-off limits for most neutral and acidic drugs, were in the range from 50ng...

  14. Correlation of acidic and basic carrier ampholyte and immobilized pH gradient two-dimensional gel electrophoresis patterns based on mass spectrometric protein identification

    DEFF Research Database (Denmark)

    Nawrocki, A; Larsen, Martin Røssel; Podtelejnikov, A V

    1998-01-01

    Separation of proteins on either carrier ampholyte-based or immobilized pH gradient-based two-dimensional (2-D) gels gives rise to electrophoretic patterns that are difficult to compare visually. In this paper we have used matrix-assisted laser desorption/ionization mass spectrometry (MALDI...

  15. Getting Back to Basics (& Acidics)

    Science.gov (United States)

    Rhodes, Sam

    2006-01-01

    This article describes a few novel acid-base experiments intended to introduce students to the basic concepts of acid-base chemistry and provide practical examples that apply directly to the study of biology and the human body. Important concepts such as the reaction between carbon dioxide and water, buffers and protein denaturation, are covered.…

  16. Broadening Horizons and Teaching Basic Biology Through Cell-Free Synthesis of Green Fluorescent Protein in a High School Laboratory Course

    Science.gov (United States)

    Albayrak, Cem; Jones, K. C.; Swartz, James R.

    2013-12-01

    Cell-free protein synthesis (CFPS) has emerged as a practical method for producing a broad variety of proteins. In addition, the direct accessibility to the reaction environment makes CFPS particularly suitable as a learning vehicle for fundamental biological concepts. Here, we describe its implementation as a teaching tool for a high school laboratory course. Ninety students in a biotechnology class used CFPS to study the effects of the concentrations of amino acids, cell extract, DNA, and the energy source on accumulation of active super-folder green fluorescent protein. Students estimated product concentrations simply by comparing solution colors to a printed green color gradient. This simple and inexpensive method allows for immediate measurements, and 26 of the 30 groups observed measurable product concentrations within 60 min. These student-generated data were then discussed to illustrate concepts of data analysis such as outliers and standard deviation. We also combined the laboratory experience with a visit to a university campus that included a laboratory tour and a college-style lecture. Our overall objective was to excite the students about the scientific enterprise and to instill a sense of personal relevance and attainability so that these students could realistically consider technical careers.

  17. International Union of Basic and Clinical Pharmacology Review: WNT/Frizzled signalling: receptor–ligand selectivity with focus on FZD-G protein signalling and its physiological relevance: IUPHAR Review 3

    Science.gov (United States)

    Dijksterhuis, J P; Petersen, J; Schulte, G

    2014-01-01

    The wingless/int1 (WNT)/Frizzled (FZD) signalling pathway controls numerous cellular processes such as proliferation, differentiation, cell-fate decisions, migration and plays a crucial role during embryonic development. Nineteen mammalian WNTs can bind to 10 FZDs thereby activating different downstream pathways such as WNT/β-catenin, WNT/planar cell polarity and WNT/Ca2+. However, the mechanisms of signalling specification and the involvement of heterotrimeric G proteins are still unclear. Disturbances in the pathways can lead to various diseases ranging from cancer, inflammatory diseases to metabolic and neurological disorders. Due to the presence of seven-transmembrane segments, evidence for coupling between FZDs and G proteins and substantial structural differences in class A, B or C GPCRs, FZDs were grouped separately in the IUPHAR GPCR database as the class FZD within the superfamily of GPCRs. Recently, important progress has been made pointing to a direct activation of G proteins after WNT stimulation. WNT/FZD and G protein coupling remain to be fully explored, although the basic observation supporting the nature of FZDs as GPCRs is compelling. Because the involvement of different (i) WNTs; (ii) FZDs; and (iii) intracellular binding partners could selectively affect signalling specification, in this review we present the current understanding of receptor/ligand selectivity of FZDs and WNTs. We pinpoint what is known about signalling specification and the physiological relevance of these interactions with special emphasis on FZD–G protein interactions. LINKED ARTICLESThis article is part of a themed section on Molecular Pharmacology of GPCRs. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2014.171.issue-5 PMID:24032637

  18. Health Insurance Basics

    Science.gov (United States)

    ... Safe Videos for Educators Search English Español Health Insurance Basics KidsHealth / For Teens / Health Insurance Basics What's ... advanced calculus was confusing. What Exactly Is Health Insurance? Health insurance is a plan that people buy ...

  19. PASCAL vs BASIC

    Science.gov (United States)

    Mundie, David A.

    1978-01-01

    A comparison between PASCAL and BASIC as general purpose microprocessor languages rates PASCAL above BASIC in such points as program structure, data types, structuring methods, control structures, procedures and functions, and ease in learning. (CMV)

  20. Basic Research Firing Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Basic Research Firing Facility is an indoor ballistic test facility that has recently transitioned from a customer-based facility to a dedicated basic research...

  1. Basics of SCI Rehabilitation

    Medline Plus

    Full Text Available ... Injury Medical Expert Videos Topics menu Topics The Basics of Spinal Cord Injury Rehabilitation Adult Injuries Spinal ... Spinal Cord Injury 101 Lawrence Vogel, MD The Basics of Pediatric SCI Rehabilitation Sara Klaas, MSW Transitions ...

  2. Basic residues in the 74-83 and 191-198 segments of protein kinase CK2 catalytic subunit are implicated in negative but not in positive regulation by the beta-subunit

    DEFF Research Database (Denmark)

    Sarno, S; Vaglio, P; Marin, O

    1997-01-01

    by the beta-subunit many fold more than that of alpha wild type, while extrastimulation by beta mutant D55L56E57A, observable with alpha wild type, is abolished with these mutants. These data support the conclusion that down regulation by the acidic residues clustered in the N-terminal moiety of beta......Protein kinase CK2 is a ubiquitous pleiotropic serine/threonine protein kinase whose holoenzyme is comprised of two catalytic (alpha and/or alpha') and two non-catalytic, beta-subunits. The beta-subunit possesses antagonist functions that can be physically dissected by generating synthetic...... fragments encompassing its N-terminal and C-terminal domains. Here we show that by mutating basic residues in the 74-77 and in the 191-198 regions of the alpha-subunit, the negative regulation by the beta-subunit and by its N-terminal synthetic fragment CK2beta-(1-77), which is observable using calmodulin...

  3. Basic Cake Decorating Workbook.

    Science.gov (United States)

    Bogdany, Mel

    Included in this student workbook for basic cake decorating are the following: (1) Drawings of steps in a basic way to ice a layer cake, how to make a paper cone, various sizes of flower nails, various sizes and types of tin pastry tubes, and special rose tubes; (2) recipes for basic decorating icings (buttercream, rose paste, and royal icing);…

  4. Programming Visual Basic 2005

    CERN Document Server

    Liberty, Jesse

    2005-01-01

    This information-packed guide helps you understand Visual Basic 2005, the next-generation release of the popular Visual Basic programming language. This book aims to make you immediately productive in creating Windows and web applications using Visual Basic 2005 and all of its tools. Perfect for experienced VB6 and novice programmers

  5. Pregnancy-associated plasma protein-A (PAPP-A) and the proform of the eosinophil major basic protein (ProMBP) are associated with increased risk of death in heart failure patients

    DEFF Research Database (Denmark)

    Dembic, Maja; Hedley, Paula L.; Torp-Pedersen, Christian

    2017-01-01

    Risk stratification and patient management in heart failure (HF) is difficult due to the unpredictable progression of the disease, necessitating the development of reliable diagnostic biomarkers to facilitate decision-making in clinical practice. Pregnancy-associated plasma protein-A (PAPP-A) is ......MBP are associated with increased risk of death from all causes in HF and are potential prognostic markers of adverse outcomes in HF patients....

  6. Basic digital signal processing

    CERN Document Server

    Lockhart, Gordon B

    1985-01-01

    Basic Digital Signal Processing describes the principles of digital signal processing and experiments with BASIC programs involving the fast Fourier theorem (FFT). The book reviews the fundamentals of the BASIC program, continuous and discrete time signals including analog signals, Fourier analysis, discrete Fourier transform, signal energy, power. The text also explains digital signal processing involving digital filters, linear time-variant systems, discrete time unit impulse, discrete-time convolution, and the alternative structure for second order infinite impulse response (IIR) sections.

  7. Basic algebraic topology

    CERN Document Server

    Shastri, Anant R

    2013-01-01

    Introduction The Basic Problem Fundamental Group Function Spaces and Quotient Spaces Relative Homotopy Some Typical Constructions Cofibrations Fibrations Categories and Functors Cell Complexes and Simplicial Complexes Basics of Convex Polytopes Cell Complexes Product of Cell Complexes Homotopical Aspects Cellular Maps Abstract Simplicial Complexes Geometric Realization of Simplicial Complexes Barycentric Subdivision Simplicial Approximation Links and Stars Covering Spaces and Fundamental Group Basic Definitions Lifting Properties Relation with the Fundamental Group Classification of Covering P

  8. Hydromechanics - basic properties

    International Nuclear Information System (INIS)

    Lee, Sung Tak; Lee, Je Geun

    1987-03-01

    This book tells of hydromechanics, which is about basic properties of hydromechanics such as conception, definition, mass, power and weight, and perfect fluid and perfect gas, hydrostatics with summary, basic equation of hydrostatics, relative balance of hydrostatics, and kinematics of hydromechanics, description method of floating, hydromechanics about basic knowledge, equation of moment, energy equation and application of Bernoulli equation, application of momentum theory, inviscid flow and fluid measuring.

  9. Basic molecular spectroscopy

    CERN Document Server

    Gorry, PA

    1985-01-01

    BASIC Molecular Spectroscopy discusses the utilization of the Beginner's All-purpose Symbolic Instruction Code (BASIC) programming language in molecular spectroscopy. The book is comprised of five chapters that provide an introduction to molecular spectroscopy through programs written in BASIC. The coverage of the text includes rotational spectra, vibrational spectra, and Raman and electronic spectra. The book will be of great use to students who are currently taking a course in molecular spectroscopy.

  10. Physical Activity Basics

    Science.gov (United States)

    ... Weight Breastfeeding Micronutrient Malnutrition State and Local Programs Physical Activity Basics Recommend on Facebook Tweet Share Compartir How much physical activity do you need? Regular physical activity helps ...

  11. Transcriptome and coexpression network analysis of the human glioma cell line Hs683 exposed to candoxin.

    Science.gov (United States)

    Jiang, Y X; Ma, Y; Cheng, Y

    2012-01-01

    Gliomas are the most common primary tumours of the central nervous system. Snake venom, such as candoxin (CDX) isolated from Bungarus candidus, inhibits glioma cell proliferation. This study explored the gene regulation profile of CDX-treated human glioma Hs683 cells. Using microarray technology and bioinformatics analyses the underlying molecular mechanism of action of CDX was evaluated by constructing gene regulation and protein-protein interaction co expression networks. CDX treatment induced a large number of related genes at the transcriptional level. The MYC gene (v-myc myelocytomatosis viral oncogene homologue [avian]) had a key role in the response of Hs683 cells to CDX treatment. Activation of MYC upregulated NDRG1 (N-myc downstream regulated 1), WNT10B (wingless-type mouse mammary tumour virus integration site family, member 10B), CASP9 (caspase 9, apoptosis-related cysteine peptidase) and CDKN2A (cyclin-dependent kinase inhibitor 2A), and downregulated ID3 (inhibitor of DNA binding 3, dominant negative helix-loop-helix protein) and SLC1A4 (solute carrier family 1 [glutamate/neutral amino acid transporter], member 4). In addition, a subnetwork was constructed among SPP1 (secreted phosphoprotein 1), SDC1 (syndecan 1) and CD44 based on protein-protein interactions, and these genes were predicted to be involved in glioma cell invasion. These findings might provide novel therapeutic targets for glioma chemotherapy.

  12. Identification, molecular and functional characterization of calmodulin gene of Phytomonas serpens 15T that shares high similarity with its pathogenic counterparts Trypanosoma cruzi.

    Science.gov (United States)

    de Souza, Tatiana de Arruda Campos Brasil; Graça-de Souza, Viviane Krominski; Lancheros, César Armando Contreras; Monteiro-Góes, Viviane; Krieger, Marco Aurélio; Goldenberg, Samuel; Yamauchi, Lucy Megumi; Yamada-Ogatta, Sueli Fumie

    2011-03-01

    In trypanosomatids, Ca²+-binding proteins can affect parasite growth, differentiation and invasion. Due to their importance for parasite maintenance, they become an attractive target for drug discovery and design. Phytomonas serpens 15T is a non-human pathogenic trypanosomatid that expresses important protein homologs of human pathogenic trypanosomatids. In this study, the coding sequence of calmodulin, a Ca²+-binding protein, of P. serpens 15T was cloned and characterized. The encoded polypeptide (CaMP) displayed high amino acid identity to homolog protein of Trypanosoma cruzi and four helix-loop-helix motifs were found. CaMP sequence analysis showed 20 amino acid substitutions compared to its mammalian counterparts. This gene is located on a chromosomal band with estimated size of 1,300 kb and two transcripts were detected by Northern blot analysis. A polyclonal antiserum raised against the recombinant protein recognized a polypeptide with an estimated size of 17 kDa in log-phase promastigote extracts. The recombinant CaMP retains its Ca²+-binding capacity.

  13. Critical requirement for aspartic acid at position 82 of myelin basic protein 73-86 for recruitment of V beta 8.2+ T cells and encephalitogenicity in the Lewis rat.

    Science.gov (United States)

    Smeltz, R B; Wauben, M H; Wolf, N A; Swanborg, R H

    1999-01-15

    We synthesized single amino acid-substituted peptide analogues of guinea pig myelin basic protein (MBP) 73-86 to study the importance of aspartic acid at residue 82 (QKSQRSQDENPV), which previous reports have suggested is a critical TCR contact residue. Whereas the wild-type 73-86 peptide elicited severe experimental autoimmune encephalomyelitis (EAE) in the Lewis rat, none of the peptide analogues with substitutions at position 82 were capable of inducing EAE. The inability to cause EAE was not due to a failure to bind MHC or to elicit T cell proliferation and cytokine secretion. T cells specific for MBP73-86 did not cross-react with any of the analogues tested, further indicating the importance of this residue in T cell responses to 73-86. Analysis by flow cytometry showed that only the wild-type 73-86 peptide was capable of recruiting V beta 8.2+ T cells, which have been shown previously to be important for disease induction. Reduced expression of the V beta 8.2 TCR was also seen in Lewis rats protected from EAE by coimmunization of MBP73-86 with 73-86(82D-->A), despite an increase in cytokine production when both peptides were present during in vitro culture. The data indicate that aspartic acid 82 is a critical TCR contact residue and is required for the recruitment of V beta 8.2+ T cells and the encephalitogenic activity of MBP73-86.

  14. BASIC Beats PASCAL.

    Science.gov (United States)

    Ever, Jacob

    1981-01-01

    Features of two versions of the BASIC programing language are compared with the features of the PASCAL programing language. The application chosen for comparison was a word processor. The conclusion was that PASCAL had the best language features, but BASIC had better systems capabilities. (MP)

  15. Basic Electronics I.

    Science.gov (United States)

    Robertson, L. Paul

    Designed for use in basic electronics programs, this curriculum guide is comprised of twenty-nine units of instruction in five major content areas: Orientation, Basic Principles of Electricity/Electronics, Fundamentals of Direct Current, Fundamentals of Alternating Current, and Applying for a Job. Each instructional unit includes some or all of…

  16. Finding Basic Writing's Place.

    Science.gov (United States)

    Sheridan-Rabideau, Mary P.; Brossell, Gordon

    1995-01-01

    Posits that basic writing serves a vital function by providing writing support for at-risk students and serves the needs of a growing student population that universities accept yet feel needs additional writing instruction. Concludes that the basic writing classroom is the most effective educational support for at-risk students and their writing.…

  17. Basic Cancer Terms

    Science.gov (United States)

    ... basics of cancer . Carcinoma Cancer that starts in skin or tissues that line the inside or cover the outside of internal organs. Cells The basic units that make up the human body. Chemoprevention The use of natural, synthetic (made in a laboratory), or biologic (from a ...

  18. Nuclear multifragmentation: Basic concepts

    Indian Academy of Sciences (India)

    2014-05-02

    May 2, 2014 ... Abstract. We present a brief overview of nuclear multifragmentation reaction. Basic formalism of canonical thermodynamical model based on equilibrium statistical mechanics is described. This model is used to calculate basic observables of nuclear multifragmentation like mass distribution, fragment ...

  19. Cloning and characterization of GRIPE, a novel interacting partner of the transcription factor E12 in developing mouse forebrain.

    Science.gov (United States)

    Heng, Julian Ik Tsen; Tan, Seong-Seng

    2002-11-08

    The helix-loop-helix (HLH) family of transcription factors are key contributors to a wide array of developmental processes, including neurogenesis and hematopoiesis. These factors are thought to exert their regulatory influences by binding to cognate promoter-DNA sequences as dimers. Although studies in mice have convincingly demonstrated that neurogenic HLH proteins such as NeuroD are intimately involved in neuronal fate determination, the role of the ubiquitously expressed HLH protein, E12, in mammalian neurogenesis remains ambiguous. To address this, a yeast two-hybrid interaction screen was employed to identify dimerization partners to E12. Screening of an embryonic day 11.5 forebrain library resulted in the cloning of GRIPE, a novel GAP-related interacting protein to E12. GRIPE binds to the HLH region of E12 and may require E12 for nuclear import. Furthermore, GRIPE may negatively regulate E12-dependent target gene transcription. High levels of GRIPE and E12 mRNA were coincidentally detected during embryogenesis, but only GRIPE mRNA levels remained high in adult brain, particularly in neurons of the cortex and hippocampus. These observations were recapitulated through an in vitro model of neurogenesis. Taken together, these results indicate that GRIPE is a novel protein dimerization of which with E12 has important consequences for cells undergoing neuronal differentiation.

  20. Eukaryotic Ribonucleases P/MRP: the Crystal Structure of the P3 Domain

    Energy Technology Data Exchange (ETDEWEB)

    Perederina, A.; Esakova, O; Quan, C; Khanova, E; Krasilnikov, A

    2010-01-01

    Ribonuclease (RNase) P is a site-specific endoribonuclease found in all kingdoms of life. Typical RNase P consists of a catalytic RNA component and a protein moiety. In the eukaryotes, the RNase P lineage has split into two, giving rise to a closely related enzyme, RNase MRP, which has similar components but has evolved to have different specificities. The eukaryotic RNases P/MRP have acquired an essential helix-loop-helix protein-binding RNA domain P3 that has an important function in eukaryotic enzymes and distinguishes them from bacterial and archaeal RNases P. Here, we present a crystal structure of the P3 RNA domain from Saccharomyces cerevisiae RNase MRP in a complex with RNase P/MRP proteins Pop6 and Pop7 solved to 2.7 {angstrom}. The structure suggests similar structural organization of the P3 RNA domains in RNases P/MRP and possible functions of the P3 domains and proteins bound to them in the stabilization of the holoenzymes' structures as well as in interactions with substrates. It provides the first insight into the structural organization of the eukaryotic enzymes of the RNase P/MRP family.

  1. Eukaryotic ribonucleases P/MRP: the crystal structure of the P3 domain.

    Science.gov (United States)

    Perederina, Anna; Esakova, Olga; Quan, Chao; Khanova, Elena; Krasilnikov, Andrey S

    2010-02-17

    Ribonuclease (RNase) P is a site-specific endoribonuclease found in all kingdoms of life. Typical RNase P consists of a catalytic RNA component and a protein moiety. In the eukaryotes, the RNase P lineage has split into two, giving rise to a closely related enzyme, RNase MRP, which has similar components but has evolved to have different specificities. The eukaryotic RNases P/MRP have acquired an essential helix-loop-helix protein-binding RNA domain P3 that has an important function in eukaryotic enzymes and distinguishes them from bacterial and archaeal RNases P. Here, we present a crystal structure of the P3 RNA domain from Saccharomyces cerevisiae RNase MRP in a complex with RNase P/MRP proteins Pop6 and Pop7 solved to 2.7 A. The structure suggests similar structural organization of the P3 RNA domains in RNases P/MRP and possible functions of the P3 domains and proteins bound to them in the stabilization of the holoenzymes' structures as well as in interactions with substrates. It provides the first insight into the structural organization of the eukaryotic enzymes of the RNase P/MRP family.

  2. Basic rocks in Finland

    International Nuclear Information System (INIS)

    Piirainen, T.; Gehoer, S.; Iljina, M.; Kaerki, A.; Paakkola, J.; Vuollo, J.

    1992-10-01

    Basic igneous rocks, containing less than 52% SiO 2 , constitute an important part of the Finnish Archaean and Proterozoic crust. In the Archaean crust exist two units which contain the majority of the basic rocks. The Arcaean basic rocks are metavolcanics and situated in the Greenstone Belts of Eastern Finland. They are divided into two units. The greenstones of the lower one are tholeiites, komatiites and basaltic komatiites. The upper consists of bimodal series of volcanics and the basic rocks of which are Fe-tholeiites, basaltic komatiites and komatiites. Proterozoic basic rocks are divided into seven groups according to their ages. The Proterozoic igneous activity started by the volominous basic magmatism 2.44 Ga ago. During this stage formed the layered intrusions and related dykes in the Northern Finland. 2.2 Ga old basic rocks are situated at the margins of Karelian formations. 2.1 Ga aged Fe-tholeiitic magmatic activity is widespread in Eastern and Northern Finland. The basic rocks of 1.97 Ga age group are met within the Karelian Schist Belts as obducted ophiolite complexes but they occur also as tholeiitic diabase dykes cutting the Karelian schists and Archean basement. The intrusions and the volcanics of the 1.9 Ga old basic igneous activity are mostly encountered around the Granitoid Complex of Central Finland. Subjotnian, 1.6 Ga aged tholeiitic diabases are situated around the Rapakivi massifs of Southern Finland, and postjotnian, 1.2 Ga diabases in Western Finland where they form dykes cutting Svecofennian rocks

  3. From basic needs to basic rights.

    Science.gov (United States)

    Facio, A

    1995-06-01

    After arriving at an understanding that basic rights refer to all human needs, it is clear that a recognition of the basic needs of female humans must precede the realization of their rights. The old Women in Development (WID) framework only understood women's needs from an androcentric perspective which was limited to practical interests. Instead, women's primary need is to be free from their subordination to men. Such an understanding places all of women's immediate needs in a new light. A human rights approach to development would see women not as beneficiaries but as people entitled to enjoy the benefits of development. Discussion of what equality before the law should mean to women began at the Third World Conference on Women in Nairobi where the issue of violence against women was first linked to development. While debate continues about the distinction between civil and political rights and economic, social, and cultural rights, the realities of women's lives do not permit such a distinction. The concept of the universality of human rights did not become codified until the UN proclaimed the Universal Declaration of Human Rights in 1948. The declaration has been criticized by feminists because the view of human rights it embodies has been too strongly influenced by a liberal Western philosophy which stresses individual rights and because it is ambiguous on the distinction between human rights and the rights of a citizen. The protection of rights afforded by the Declaration, however, should not be viewed as a final achievement but as an ongoing struggle. International conferences have led to an analysis of the human-rights approach to sustainable development which concludes that women continue to face the routine denial of their rights. Each human right must be redefined from the perspective of women's needs, which must also be redefined. Women must forego challenging the concept of the universality of human rights in order to overcome the argument of cultural

  4. Basic stress analysis

    CERN Document Server

    Iremonger, M J

    1982-01-01

    BASIC Stress Analysis aims to help students to become proficient at BASIC programming by actually using it in an important engineering subject. It also enables the student to use computing as a means of learning stress analysis because writing a program is analogous to teaching-it is necessary to understand the subject matter. The book begins by introducing the BASIC approach and the concept of stress analysis at first- and second-year undergraduate level. Subsequent chapters contain a summary of relevant theory, worked examples containing computer programs, and a set of problems. Topics c

  5. Quantum electronics basic theory

    CERN Document Server

    Fain, V M; Sanders, J H

    1969-01-01

    Quantum Electronics, Volume 1: Basic Theory is a condensed and generalized description of the many research and rapid progress done on the subject. It is translated from the Russian language. The volume describes the basic theory of quantum electronics, and shows how the concepts and equations followed in quantum electronics arise from the basic principles of theoretical physics. The book then briefly discusses the interaction of an electromagnetic field with matter. The text also covers the quantum theory of relaxation process when a quantum system approaches an equilibrium state, and explai

  6. The amino acid sequence of the light chain of Acanthamoeba myosin IC.

    Science.gov (United States)

    Wang, Z Y; Sakai, J; Matsudaira, P T; Baines, I C; Sellers, J R; Hammer, J A; Korn, E D

    1997-06-01

    The amino acid sequence of the light chain of Acanthamoeba myosin IC deduced from the cDNA sequence comprises 149 amino acids with a calculated molecular weight of 16,739. All but the 3 N-terminal residues were also determined by amino acid sequencing of the purified protein, which also showed the N-terminus to be blocked. Phylogenetic analysis shows Acanthamoeba myosin IC light chain to be more similar to the calmodulin subfamily of EF-hand calcium-modulated proteins than to the myosin II essential light chain or regulatory light chain subfamilies. In pairwise comparisons, the myosin IC light chain sequence is most similar to sequences of calmodulins (approximately 50% identical) and a squid calcium-binding protein (approximately 43% identical); the sequence is approximately 37% identical to the calcium-binding essential light chain of Physarum myosin II and approximately 30% identical to the essential light chain of Acanthamoeba myosin II, and the essential light chain and regulatory light chain of Dictyostelium myosin II. The sequence predicts four helix-loop-helix domains with possible calcium-binding sites in domains I and III, suggesting that calcium may affect the activity of this unconventional myosin. This is the first report of the sequence of an unconventional myosin light chain other than calmodulin.

  7. HIV Treatment: The Basics

    Science.gov (United States)

    ... AIDS Drugs Clinical Trials Apps skip to content HIV Treatment Home Understanding HIV/AIDS Fact Sheets HIV ... 4 p.m. ET) Send us an email HIV Treatment: The Basics Last Reviewed: March 22, 2018 ...

  8. Basics of SCI Rehabilitation

    Medline Plus

    Full Text Available ... Peer Counseling Blog About Media Donate Spinal Cord Injury Medical Expert Videos Topics menu Topics The Basics of Spinal Cord Injury Rehabilitation Adult Injuries Spinal Cord Injury 101 David ...

  9. Basics of SCI Rehabilitation

    Medline Plus

    Full Text Available ... Topic Resources Peer Counseling Blog About Media Donate Spinal Cord Injury Medical Expert Videos Topics menu Topics The Basics of Spinal Cord Injury Rehabilitation Adult Injuries Spinal Cord Injury 101 David ...

  10. Basics of SCI Rehabilitation

    Medline Plus

    Full Text Available ... About Media Donate Spinal Cord Injury Medical Expert Videos Topics menu Topics The Basics of Spinal Cord ... LLC Understanding Spinal Cord Injury About Us Expert Videos Contact Us Personal Experience Videos Blog Videos By ...

  11. Noise Radar Technology Basics

    National Research Council Canada - National Science Library

    Thayaparan, T; Wernik, C

    2006-01-01

    .... In this report, the basic theory of noise radar design is treated. The theory supports the use of noise waveforms for radar detection and imaging in such applications as covert military surveillance and reconnaissance...

  12. Basics of SCI Rehabilitation

    Medline Plus

    Full Text Available ... Counseling Blog About Media Donate Spinal Cord Injury Medical Expert Videos Topics menu Topics The Basics of ... injury? What is a Spinal Cord Injury? SCI Medical Experts People Living With SCI Personal Experiences By ...

  13. Basics of SCI Rehabilitation

    Medline Plus

    Full Text Available ... Topic Resources Peer Counseling Blog About Media Donate Spinal Cord Injury Medical Expert Videos Topics menu Topics The Basics of Spinal Cord Injury Rehabilitation Adult Injuries Spinal Cord Injury 101 ...

  14. Video Screen Capture Basics

    Science.gov (United States)

    Dunbar, Laura

    2014-01-01

    This article is an introduction to video screen capture. Basic information of two software programs, QuickTime for Mac and BlueBerry Flashback Express for PC, are also discussed. Practical applications for video screen capture are given.

  15. Basics of SCI Rehabilitation

    Medline Plus

    Full Text Available ... RN Pediatric Injuries Pediatric Spinal Cord Injury 101 Lawrence Vogel, MD The Basics of Pediatric SCI Rehabilitation ... Rogers, PT Recreational Therapy after Spinal Cord Injury Jennifer Piatt, PhD Kristine Cichowski, MS Read Bio Founding ...

  16. Basic Information about Mercury

    Science.gov (United States)

    ... Your Environment Contact Us Share Basic Information about Mercury On this page: What is mercury? Emissions of ... Consumer products that traditionally contain mercury What is Mercury? Mercury is a naturally-occurring chemical element found ...

  17. Basics of SCI Rehabilitation

    Medline Plus

    Full Text Available ... How Peer Counseling Works Julie Gassaway, MS, RN Pediatric Injuries Pediatric Spinal Cord Injury 101 Lawrence Vogel, MD The Basics of Pediatric SCI Rehabilitation Sara Klaas, MSW Transitions for Children ...

  18. Basics of SCI Rehabilitation

    Medline Plus

    Full Text Available ... Spinal Cord Injury 101 Lawrence Vogel, MD The Basics of Pediatric SCI Rehabilitation Sara Klaas, MSW Transitions for Children with Spinal Cord Injury Patricia Mucia, RN Family Life After Pediatric Spinal Injury Dawn Sheaffer, MSW Rehabilitation ...

  19. Basics of SCI Rehabilitation

    Medline Plus

    Full Text Available ... Cord Injury Medical Expert Videos Topics menu Topics The Basics of Spinal Cord Injury Rehabilitation Adult Injuries ... Therapy-Lokomat T. George Hornby, PhD, PT Empowering the Patient After Spinal Cord Injury Guy W. Fried, ...

  20. Radionuclide Basics: Iodine

    Science.gov (United States)

    ... Search Radiation Protection Contact Us Share Radionuclide Basics: Iodine Iodine (chemical symbol I) is a chemical element. ... in the environment Iodine sources Iodine and health Iodine in the Environment All 37 isotopes of iodine ...

  1. Normal adult ramified microglia separated from other central nervous system macrophages by flow cytometric sorting: Phenotypic differences defined and direct ex vivo antigen presentation to myelin basic protein-reactive CD4{sup +} T cells compared

    Energy Technology Data Exchange (ETDEWEB)

    Ford, A.L.; Goodsall, A.L.; Sedgwick, J.D. [Centenary Institute of Cancer Medicine and Cell Biology, Sydney (Australia)] [and others

    1995-05-01

    Ramified microglia in the adult central nervous system (CNS) are the principal glial element up-regulating MHC class I and II expression in response to inflammatory events or neuronal damage. A proportion of these cells also express MHC class II constitutively in the normal CNS. The role of microglia as APCs for CD4{sup +} cells extravasating into the CNS remains undefined. In this study, using irradiation bone marrow chimeras in CD45-congenic rats, the phenotype CD45{sup low}CD11b/c{sup +} is shown to identify microglial cells specifically within the CNS. Highly purified populations of microglia and nonmicroglial but CNS-associated macrophages (CD45{sup high}CD11b/c{sup +}) have been obtained directly from the adult CNS, by using flow cytometric sorting. Morphologically, freshly isolated microglia vs other CNS macrophages are quite distinct. Of the two populations recovered from the normal CNS, it is the minority CD45{sup high}CD11 b/c{sup +} transitional macrophage population, and not microglia, that is the effective APC for experimental autoimmune encephalomyelitis-inducing CD4{sup +} myelin basic protein (MBP)-reactive T cells. CD45{sup high}CD11b/c{sup +} CNS macrophages also stimulate MBP-reactive T cells without addition of MBP to culture suggesting presentation of endogenous Ag. This is the first study in which microglia vs other CNS macrophages have been analyzed for APC ability directly from the CNS, with substantial cross-contamination between the two populations eliminated. The heterogeneity of these populations in terms of APC function is clearly demonstrated. Evidence is still lacking that adult CNS microglia have the capacity to interact with and stimulate CD4{sup +} T cells to proliferate or secrete IL-2. 60 refs., 6 figs., 1 tab.

  2. T-cell seeding: neonatal transfer of anti-myelin basic protein T-cell lines renders Fischer rats susceptible later in life to the active induction of experimental autoimmune encephalitis.

    Science.gov (United States)

    Volovitz, Ilan; Mor, Felix; Machlenkin, Arthur; Machlenkin, Athur; Goldberger, Ofir; Marmor, Yotvat; Eisenbach, Lea; Cohen, Irun R; Cohen, Irun

    2009-09-01

    Fischer strain rats resist active induction of experimental autoimmune encephalomyelitis (EAE) following immunization with guinea-pig myelin basic protein (MBP) in complete Freund's adjuvant (CFA). Nevertheless, we now report that an encephalitogenic CD4(+) anti-MBP T-cell line could be developed from actively immunized Fischer rats. Adoptive transfer of the activated line mediated acute EAE in adult Fischer rats, but not in 1-day-old rats. Moreover, we found that both resting and activated anti-MBP T cells injected 1 day post-natally rendered these rats susceptible later in life to the active induction of EAE by immunization with MBP/CFA. The actively induced EAE manifested the accelerated onset of a secondary, memory-type response. Resting anti-MBP T cells injected even up to 2 weeks post-natally produced no clinical signs but seeded 50-100% of the recipients for an active encephalitogenic immune response to MBP. An earlier T-cell injection (1-2 days) produced a higher incidence and stronger response. The transferred resting T cells entered the neonatal spleen and thymus and proliferated there but did not change the total anti-MBP precursor number in adults. Splenocytes harvested from rats that were injected neonatally but not exposed to MBP in vivo proliferated strongly and produced significant amounts of interferon-gamma to MBP in vitro. Similar results were observed in rats injected with resting T-cell lines reactive to ovalbumin, suggesting that the neonatal injection of resting T cells specific for a self or for a foreign antigen can seed the immune system with the potential for an enhanced effector response to that antigen later in life.

  3. [The effect of blue light on human retinal pigment epithelium cells α1D subunit protein expression and vascular endothelial growth factor and basic fibroblast growth factor secretion in vitro].

    Science.gov (United States)

    Li, Haihui; Cai, Shanjun; Gong, Xin; Wu, Zhipeng; Lyn, Jianping; Su, Gang; Xie, Bing

    2014-11-01

    To investigate the effect of blue light on human retinal pigment epithelium (RPE) α1D subunit protein expression and its relationship with vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) secretion in vitro. The fourth generation cultured human RPE cells in vitro were randomly divided into 4 groups, group A (control), group B (exposure to blue light), group C (exposure to blue light+nifedipine), group D [exposure to blue light+(-)Bay K8644]. Cells were exposed to blue light (2 000 ± 500) lx for 6 hours, and cells culture completed 24 hours later. VEGF and bFGF concentration were assayed by enzyme linked immunosorbent assay (ELISA). Real-time polymerase chain reaction was used to analysis L-type calcium channel α1D subunit mRNA expression. Western blot was used to examine the protein expression of L-type calcium channel α1D subunit. Analysis of variance was used to compare the difference of α1D subunit mRNA and protein expression, VEGF and bFGF concentration between groups. Correlation analysis was used to show the relationship between α1D subunit protein expression and concentration of VEGF and bFGF. (1) There is significant statistically difference in the population mean of VEGF and bFGF concentration in four groups (F = 99.441, 21.310, P = 0.000,0.000) . VEGF and bFGF concentration in group B (3 281.51 ± 251.73, 1 346.81 ± 62.27) and group D (3 808.01 ± 94.01, 1 485.82 ± 108.97) was higher than it was in group A (2 401.09 ± 228.07, 1 232.42 ± 65.41) , which was statistically different (P = 0.000, 0.000, 0.019, 0.000). And it was higher in group D (3 808.01 ± 94.01, 1 485.82 ± 108.97) compared with group B (3 281.51 ± 251.73, 1 346.81 ± 62.27) (P = 0.000, 0.006). While, it was lower in group C (1 927.28 ± 143.11, 1 149.39 ± 62.99) than it was in group B (3 281.51 ± 251.73, 1 346.81 ± 62.27) (P = 0.000, 0.000) . (2) The mean of mRNA expression of α1D subunit between four groups was statistically significant (F

  4. Basic Concurrency Theory

    DEFF Research Database (Denmark)

    Løvengreen, Hans Henrik

    2002-01-01

    In this set of notes, we present some of the basic theory underlying the discipline of programming with concurrent processes/threads. The notes are intended to supplement a standard textbook on concurrent programming.......In this set of notes, we present some of the basic theory underlying the discipline of programming with concurrent processes/threads. The notes are intended to supplement a standard textbook on concurrent programming....

  5. Transportation Emissions: some basics

    DEFF Research Database (Denmark)

    Kontovas, Christos A.; Psaraftis, Harilaos N.

    2016-01-01

    . The main purpose of this chapter is to introduce some basic concepts that are relevant in the quest of green transportation logistics. First, we present the basics of estimating emissions from transportation activities, the current statistics and future trends, as well as the total impact of air emissions...... of the energy efficiency gap and examines why governments and companies may forego cost-effective investments in energy efficiency, even though they could significantly reduce energy consumption at a lower cost....

  6. Basic Finite Element Method

    International Nuclear Information System (INIS)

    Lee, Byeong Hae

    1992-02-01

    This book gives descriptions of basic finite element method, which includes basic finite element method and data, black box, writing of data, definition of VECTOR, definition of matrix, matrix and multiplication of matrix, addition of matrix, and unit matrix, conception of hardness matrix like spring power and displacement, governed equation of an elastic body, finite element method, Fortran method and programming such as composition of computer, order of programming and data card and Fortran card, finite element program and application of nonelastic problem.

  7. Basic Monetary Economics

    OpenAIRE

    Farm, Ante

    2017-01-01

    This is an introduction to money and the workings of the financial system. The creation of money is discussed in detail in Chapter 1. Chapter 2 explains how international payments can add to money creation but also generate a new type of money, usually called Eurodollars. Basic securities are defined and characterized in Chapter 3, namely bills, bonds and shares, but basic derivatives, like futures, swaps, and options, are also discussed. Chapter 4 deals with pricing by banks when extending l...

  8. Catalyst in Basic Oleochemicals

    OpenAIRE

    Eva Suyenty; Herlina Sentosa; Mariani Agustine; Sandy Anwar; Abun Lie; Erwin Sutanto

    2007-01-01

    Currently Indonesia is the world largest palm oil producer with production volume reaching 16 million tones per annum. The high crude oil and ethylene prices in the last 3 – 4 years contribute to the healthy demand growth for basic oleochemicals: fatty acids and fatty alcohols. Oleochemicals are starting to replace crude oil derived products in various applications. As widely practiced in petrochemical industry, catalyst plays a very important role in the production of basic oleochemic...

  9. A bHLH transcription factor, DvIVS, is involved in regulation of anthocyanin synthesis in dahlia (Dahlia variabilis).

    Science.gov (United States)

    Ohno, Sho; Hosokawa, Munetaka; Hoshino, Atsushi; Kitamura, Yoshikuni; Morita, Yasumasa; Park, Kyeung-Ii; Nakashima, Akiko; Deguchi, Ayumi; Tatsuzawa, Fumi; Doi, Motoaki; Iida, Shigeru; Yazawa, Susumu

    2011-10-01

    Dahlias (Dahlia variabilis) exhibit a wide range of flower colours because of accumulation of anthocyanin and other flavonoids in their ray florets. Two lateral mutants were used that spontaneously occurred in 'Michael J' (MJW) which has yellow ray florets with orange variegation. MJOr, a bud mutant producing completely orange ray florets, accumulates anthocyanins, flavones, and butein, and MJY, another mutant producing completely yellow ray florets, accumulates flavones and butein. Reverse transcription-PCR analysis showed that expression of chalcone synthase 1 (DvCHS1), flavanone 3-hydroxylase (DvF3H), dihydroflavonol 4-reductase (DvDFR), anthocyanidin synthase (DvANS), and DvIVS encoding a basic helix-loop-helix transcription factor were suppressed, whereas that of chalcone isomerase (DvCHI) and DvCHS2, another CHS with 69% nucleotide identity with DvCHS1, was not suppressed in the yellow ray florets of MJY. A 5.4 kb CACTA superfamily transposable element, transposable element of Dahlia variabilis 1 (Tdv1), was found in the fourth intron of the DvIVS gene of MJW and MJY, and footprints of Tdv1 were detected in the variegated flowers of MJW. It is shown that only one type of DvIVS gene was expressed in MJOr, whereas these plants are likely to have three types of the DvIVS gene. On the basis of these results, the mechanism regulating the formation of orange and yellow ray florets in dahlia is discussed.

  10. A bHLH gene from Tamarix hispida improves abiotic stress tolerance by enhancing osmotic potential and decreasing reactive oxygen species accumulation.

    Science.gov (United States)

    Ji, Xiaoyu; Nie, Xianguang; Liu, Yujia; Zheng, Lei; Zhao, Huimin; Zhang, Bing; Huo, Lin; Wang, Yucheng

    2016-02-01

    Basic helix-loop-helix (bHLH) leucine-zipper transcription factors play important roles in abiotic stress responses. However, their specific roles in abiotic stress tolerance are not fully known. Here, we functionally characterized a bHLH gene, ThbHLH1, from Tamarix hispida in abiotic stress tolerance. ThbHLH1 specifically binds to G-box motif with the sequence of 'CACGTG'. Transiently transfected T. hispida plantlets with transiently overexpressed ThbHLH1 and RNAi-silenced ThbHLH1 were generated for gain- and loss-of-function analysis. Transgenic Arabidopsis thaliana lines overexpressing ThbHLH1 were generated to confirm the gain- and loss-of-function analysis. Overexpression of ThbHLH1 significantly elevates glycine betaine and proline levels, increases Ca(2+) concentration and enhances peroxidase (POD) and superoxide dismutase (SOD) activities to decrease reactive oxygen species (ROS) accumulation. Additionally, ThbHLH1 regulates the expression of the genes including P5CS, BADH, CaM, POD and SOD, to activate the above physiological changes, and also induces the expression of stress tolerance-related genes LEAs and HSPs. These data suggest that ThbHLH1 induces the expression of stress tolerance-related genes to improve abiotic stress tolerance by increasing osmotic potential, improving ROS scavenging capability and enhancing second messenger in stress signaling cascades. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  11. CCAR1 is required for Ngn3-mediated endocrine differentiation

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Chung-Kuang [Department of Life Science, National Chung Cheng University, Chia-Yi, Taiwan, ROC (China); Lai, Yi-Chyi [Department of Microbiology and Immunology, Chung Shan Medical University, Taichung, Taiwan, ROC (China); Lin, Yung-Fu; Chen, Hau-Ren [Department of Life Science, National Chung Cheng University, Chia-Yi, Taiwan, ROC (China); Chiang, Ming-Ko, E-mail: biomkc@ccu.edu.tw [Department of Life Science, National Chung Cheng University, Chia-Yi, Taiwan, ROC (China)

    2012-02-10

    Highlights: Black-Right-Pointing-Pointer We identify CCAR1 to directly interact with Ngn3. Black-Right-Pointing-Pointer CCAR1 is co-localized with Ngn3 in the nucleus. Black-Right-Pointing-Pointer CCAR1 cooperates with Ngn3 in activating NeuroD expression. Black-Right-Pointing-Pointer CCAR1 is required for Ngn3-mediated PANC-1 transdifferentiation. -- Abstract: Neurogenin3 (Ngn3) is a basic helix-loop-helix transcription factor that specifies pancreatic endocrine cell fates during pancreas development. It can also initiate a transdifferentiation program when expressed in pancreatic exocrine and ductal cells. However, how Ngn3 initiates a transcriptional cascade to achieve endocrine differentiation is still poorly understood. Here, we show that cell cycle and apoptosis regulator 1 (CCAR1), which is a transcriptional coactivator for nuclear receptors, also interacts with Ngn3. The association between Ngn3 and CCAR1 was verified by pull-down assays and co-immunoprecipitation analyses. Using gene reporter assays, we found that CCAR1 is essential for Ngn3 to activate the expression of the reporter genes containing the NeuroD promoter. Moreover, down-regulation of endogenous CCAR1 in the PANC-1 pancreatic ductal cell line inhibits the transdifferentiation program initiated by Ngn3. CCAR1 is, therefore, a novel partner of Ngn3 in mediating endocrine differentiation.

  12. ThMYC4E, candidate Blue aleurone 1 gene controlling the associated trait in Triticum aestivum.

    Directory of Open Access Journals (Sweden)

    Na Li

    Full Text Available Blue aleurone is a useful and interesting trait in common wheat that was derived from related species. Here, transcriptomes of blue and white aleurone were compared for isolating Blue aleurone 1 (Ba1 transferred from Thinopyrum ponticum. In the genes involved in anthocyanin biosynthesis, only a basic helix-loop-helix (bHLH transcription factor, ThMYC4E, had a higher transcript level in blue aleurone phenotype, and was homologous to the genes on chromosome 4 of Triticum aestivum. ThMYC4E carried the characteristic domains (bHLH-MYC_N, HLH and ACT-like of a bHLH transcription factor, and clustered with genes regulating anthocyanin biosynthesis upon phylogenetic analysis. The over-expression of ThMYC4E regulated anthocyanin biosynthesis with the coexpression of the MYB transcription factor ZmC1 from maize. ThMYC4E existed in the genomes of the addition, substitution and near isogenic lines with the blue aleurone trait derived from Th. ponticum, and could not be detected in any germplasm of T. urartu, T. monococcum, T. turgidum, Aegilops tauschii or T. aestivum, with white aleurone. These results suggested that ThMYC4E was candidate Ba1 gene controlling the blue aleurone trait in T. aestivum genotypes carrying Th. ponticum introgression. The ThMYC4E isolation aids in better understanding the genetic mechanisms of the blue aleurone trait and in its more effective use during wheat breeding.

  13. Differential contribution of transcription factors to Arabidopsis thaliana defence against Spodoptera littoralis.

    Directory of Open Access Journals (Sweden)

    Fabian eSchweizer

    2013-02-01

    Full Text Available In response to insect herbivory, Arabidopsis plants activate the synthesis of the phytohormone jasmonate-isoleucine (JA-Ile, which binds to a complex consisting of the receptor COI1 and JAZ repressors. Upon proteasome-mediated JAZ degradation, basic helix-loop-helix transcription factors (TFs MYC2, MYC3, and MYC4 become activated and this results in the expression of defence genes. Although the jasmonate (JA pathway is known to be essential for the massive transcriptional reprogramming that follows herbivory, there is however little information on other TFs that are required for defence against herbivores and whether they contribute significantly to JA-dependent defence gene expression. By transcriptome profiling, we identified 41 TFs that were induced in response to herbivory by the generalist Spodoptera littoralis. Among them, nine genes, including WRKY18, WRKY40, ANAC019, ANAC055, ZAT10, ZAT12, AZF2, ERF13, and RRTF1, were found to play a significant role in resistance to S. littoralis herbivory. However, compared to the triple mutant myc234 that is as sensitive as coi1-1 to herbivory, knockout lines of these nine TFs were only partially more sensitive to S. littoralis and showed only minor gene expression changes at the whole genome level. Data thus reveal that MYC2, MYC3, and MYC4 are master regulators of Arabidopsis resistance to a generalist herbivore and identify new genes involved in insect defence.

  14. Differential Contribution of Transcription Factors to Arabidopsis thaliana Defense Against Spodoptera littoralis.

    Science.gov (United States)

    Schweizer, Fabian; Bodenhausen, Natacha; Lassueur, Steve; Masclaux, Frédéric G; Reymond, Philippe

    2013-01-01

    In response to insect herbivory, Arabidopsis plants activate the synthesis of the phytohormone jasmonate-isoleucine, which binds to a complex consisting of the receptor COI1 and JAZ repressors. Upon proteasome-mediated JAZ degradation, basic helix-loop-helix transcription factors (TFs) MYC2, MYC3, and MYC4 become activated and this results in the expression of defense genes. Although the jasmonate (JA) pathway is known to be essential for the massive transcriptional reprogramming that follows herbivory, there is however little information on other TFs that are required for defense against herbivores and whether they contribute significantly to JA-dependent defense gene expression. By transcriptome profiling, we identified 41 TFs that were induced in response to herbivory by the generalist Spodoptera littoralis. Among them, nine genes, including WRKY18, WRKY40, ANAC019, ANAC055, ZAT10, ZAT12, AZF2, ERF13, and RRTF1, were found to play a significant role in resistance to S. littoralis herbivory. Compared to the triple mutant myc234 that is as sensitive as coi1-1 to herbivory, knockout lines of these nine TFs were only partially more sensitive to S. littoralis but, however, some displayed distinct gene expression changes at the whole-genome level. Data thus reveal that MYC2, MYC3, and MYC4 are master regulators of Arabidopsis resistance to a generalist herbivore and identify new genes involved in insect defense.

  15. Vsx2 in the zebrafish retina: restricted lineages through derepression

    Directory of Open Access Journals (Sweden)

    Higashijima Shin-ichi

    2009-04-01

    Full Text Available Abstract Background The neurons in the vertebrate retina arise from multipotent retinal progenitor cells (RPCs. It is not clear, however, which progenitors are multipotent or why they are multipotent. Results In this study we show that the homeodomain transcription factor Vsx2 is initially expressed throughout the retinal epithelium, but later it is downregulated in all but a minor population of bipolar cells and all Müller glia. The Vsx2-negative daughters of Vsx2-positive RPCs divide and give rise to all other cell types in the retina. Vsx2 is a repressor whose targets include transcription factors such as Vsx1, which is expressed in the progenitors of distinct non-Vsx2 bipolars, and the basic helix-loop-helix transcription factor Ath5, which restricts the fate of progenitors to retinal ganglion cells, horizontal cells, amacrine cells and photoreceptors fates. Foxn4, expressed in the progenitors of amacrine and horizontal cells, is also negatively regulated by Vsx2. Conclusion Our data thus suggest Vsx2-positive RPCs are fully multipotent retinal progenitors and that when Vsx2 is downregulated, Vsx2-negative progenitors escape Vsx2 repression and so are able to express factors that restrict lineage potential.

  16. Omega-3 Polyunsaturated Fatty Acids Enhance Neuronal Differentiation in Cultured Rat Neural Stem Cells

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    Masanori Katakura

    2013-01-01

    Full Text Available Polyunsaturated fatty acids (PUFAs can induce neurogenesis and recovery from brain diseases. However, the exact mechanisms of the beneficial effects of PUFAs have not been conclusively described. We recently reported that docosahexaenoic acid (DHA induced neuronal differentiation by decreasing Hes1 expression and increasing p27kip1 expression, which causes cell cycle arrest in neural stem cells (NSCs. In the present study, we examined the effect of eicosapentaenoic acid (EPA and arachidonic acid (AA on differentiation, expression of basic helix-loop-helix transcription factors (Hes1, Hes6, and NeuroD, and the cell cycle of cultured NSCs. EPA also increased mRNA levels of Hes1, an inhibitor of neuronal differentiation, Hes6, an inhibitor of Hes1, NeuroD, and Map2 mRNA and Tuj-1-positive cells (a neuronal marker, indicating that EPA induced neuronal differentiation. EPA increased the mRNA levels of p21cip1 and p27kip1, a cyclin-dependent kinase inhibitor, which indicated that EPA induced cell cycle arrest. Treatment with AA decreased Hes1 mRNA but did not affect NeuroD and Map2 mRNA levels. Furthermore, AA did not affect the number of Tuj-1-positive cells or cell cycle progression. These results indicated that EPA could be involved in neuronal differentiation by mechanisms alternative to those of DHA, whereas AA did not affect neuronal differentiation in NSCs.

  17. Analysis of the Hand1 cell lineage reveals novel contributions to cardiovascular, neural crest, extra-embryonic, and lateral mesoderm derivatives.

    Science.gov (United States)

    Barnes, Ralston M; Firulli, Beth A; Conway, Simon J; Vincentz, Joshua W; Firulli, Anthony B

    2010-11-01

    The basic Helix-Loop-Helix (bHLH) transcription factors Hand1 and Hand2 play critical roles in the development of multiple organ systems during embryogenesis. The dynamic expression patterns of these two factors within developing tissues obfuscate their respective unique and redundant organogenic functions. To define cell lineages potentially dependent upon Hand gene expression, we generated a mutant allele in which the coding region of Hand1 is replaced by Cre recombinase. Subsequent Cre-mediated activation of β-galactosidase or eYFP reporter alleles enabled lineage trace analyses that clearly define the fate of Hand1-expressing cells. Hand1-driven Cre marks specific lineages within the extra embryonic tissues, placenta, sympathetic nervous system, limbs, jaw, and several cell types within the cardiovascular system. Comparisons between Hand1 expression and Hand1-lineage greatly refine our understanding of its dynamic spatial-temporal expression domains and raise the possibility of novel Hand1 functions in structures not thought to be Hand1-dependent. © 2010 Wiley-Liss, Inc.

  18. Bisphenol A, an endocrine-disrupting chemical, and brain development.

    Science.gov (United States)

    Itoh, Kyoko; Yaoi, Takeshi; Fushiki, Shinji

    2012-08-01

    Bisphenol A (BPA) is an endocrine-disrupting chemical, widely used in various industries and the field of dentistry. The consequent increase in BPA exposure among humans has led us to some concerns regarding the potential deleterious effects on reproduction and brain development. The emphasis of this review is on the effects of prenatal and lactational exposure to low doses of BPA on brain development in mice. We demonstrated that prenatal exposure to BPA affected fetal murine neocortical development by accelerating neuronal differentiation/migration during the early embryonic stage, which was associated with up- and down-regulation of the genes critical for brain development, including the basic helix-loop-helix transcription factors. In the adult mice brains, both abnormal neocortical architecture and abnormal corticothalamic projections persisted in the group exposed to the BPA. Functionally, BPA exposure disturbed murine behavior, accompanied with a disrupted neurotransmitter system, including monoamines, in the postnatal development period and in adult mice. We also demonstrated that epigenetic alterations in promoter-associated CpG islands might underlie some of the effects on brain development after exposure to BPA. © 2012 Japanese Society of Neuropathology.

  19. GTL1 and DF1 regulate root hair growth through transcriptional repression of ROOT HAIR DEFECTIVE 6-LIKE 4 in Arabidopsis

    Science.gov (United States)

    Breuer, Christian; Kawamura, Ayako; Clark, Natalie M.; Morohashi, Kengo; Busch, Wolfgang; Benfey, Philip N.; Sozzani, Rosangela

    2018-01-01

    ABSTRACT How plants determine the final size of growing cells is an important, yet unresolved, issue. Root hairs provide an excellent model system with which to study this as their final cell size is remarkably constant under constant environmental conditions. Previous studies have demonstrated that a basic helix-loop helix transcription factor ROOT HAIR DEFECTIVE 6-LIKE 4 (RSL4) promotes root hair growth, but how hair growth is terminated is not known. In this study, we demonstrate that a trihelix transcription factor GT-2-LIKE1 (GTL1) and its homolog DF1 repress root hair growth in Arabidopsis. Our transcriptional data, combined with genome-wide chromatin-binding data, show that GTL1 and DF1 directly bind the RSL4 promoter and regulate its expression to repress root hair growth. Our data further show that GTL1 and RSL4 regulate each other, as well as a set of common downstream genes, many of which have previously been implicated in root hair growth. This study therefore uncovers a core regulatory module that fine-tunes the extent of root hair growth by the orchestrated actions of opposing transcription factors. PMID:29439132

  20. Embryonic expression of zebrafish MiT family genes tfe3b, tfeb, and tfec.

    Science.gov (United States)

    Lister, James A; Lane, Brandon M; Nguyen, Anhthu; Lunney, Katherine

    2011-11-01

    The MiT family comprises four genes in mammals: Mitf, Tfe3, Tfeb, and Tfec, which encode transcription factors of the basic-helix-loop-helix/leucine zipper class. Mitf is well-known for its essential role in the development of melanocytes, however the functions of the other members of this family, and of interactions between them, are less well understood. We have now characterized the complete set of MiT genes from zebrafish, which totals six instead of four. The zebrafish genome contain two mitf (mitfa and mitfb), two tfe3 (tfe3a and tfe3b), and single tfeb and tfec genes; this distribution is shared with other teleosts. We present here the sequence and embryonic expression patterns for the zebrafish tfe3b, tfeb, and tfec genes, and identify a new isoform of tfe3a. These findings will assist in elucidating the roles of the MiT gene family over the course of vertebrate evolution. Copyright © 2011 Wiley-Liss, Inc.

  1. BMP and Delta/Notch signaling control the development of amphioxus epidermal sensory neurons: insights into the evolution of the peripheral sensory system.

    Science.gov (United States)

    Lu, Tsai-Ming; Luo, Yi-Jyun; Yu, Jr-Kai

    2012-06-01

    The evolution of the nervous system has been a topic of great interest. To gain more insight into the evolution of the peripheral sensory system, we used the cephalochordate amphioxus. Amphioxus is a basal chordate that has a dorsal central nervous system (CNS) and a peripheral nervous system (PNS) comprising several types of epidermal sensory neurons (ESNs). Here, we show that a proneural basic helix-loop-helix gene (Ash) is co-expressed with the Delta ligand in ESN progenitor cells. Using pharmacological treatments, we demonstrate that Delta/Notch signaling is likely to be involved in the specification of amphioxus ESNs from their neighboring epidermal cells. We also show that BMP signaling functions upstream of Delta/Notch signaling to induce a ventral neurogenic domain. This patterning mechanism is highly similar to that of the peripheral sensory neurons in the protostome and vertebrate model animals, suggesting that they might share the same ancestry. Interestingly, when BMP signaling is globally elevated in amphioxus embryos, the distribution of ESNs expands to the entire epidermal ectoderm. These results suggest that by manipulating BMP signaling levels, a conserved neurogenesis circuit can be initiated at various locations in the epidermal ectoderm to generate peripheral sensory neurons in amphioxus embryos. We hypothesize that during chordate evolution, PNS progenitors might have been polarized to different positions in various chordate lineages owing to differential regulation of BMP signaling in the ectoderm.

  2. Sharp-1 regulates TGF-β signaling and skeletal muscle regeneration.

    Science.gov (United States)

    Acharjee, Sujata; Chung, Teng-Kai; Gopinadhan, Suma; Shankar, Shilpa Rani; Wang, Yaju; Li, Li; Vercherat, Cecile; Gulbagci, Neriman Tuba; Rossner, Moritz; Taneja, Reshma

    2014-02-01

    Sharp-1 is a basic helix-loop-helix (bHLH) transcriptional repressor that is involved in a number of cellular processes. Our previous studies have demonstrated that Sharp-1 is a negative regulator of skeletal myogenesis and it blocks differentiation of muscle precursor cells by modulating the activity of MyoD. In order to understand its role in pre- and post-natal myogenesis, we assessed skeletal muscle development and freeze-injury-induced regeneration in Sharp-1-deficient mice. We show that embryonic skeletal muscle development is not impaired in the absence of Sharp-1; however, post-natally, the regenerative capacity is compromised. Although the initial phases of injury-induced regeneration proceed normally in Sharp-1(-/-) mice, during late stages, the mutant muscle exhibits necrotic fibers, calcium deposits and fibrosis. TGF-β expression, as well as levels of phosphorylated Smad2 and Smad3, are sustained in the mutant tissue and treatment with decorin, which blocks TGF-β signaling, improves the histopathology of Sharp-1(-/-) injured muscles. In vitro, Sharp-1 associates with Smad3, and its overexpression inhibits TGF-β- and Smad3-mediated expression of extracellular matrix genes in myofibroblasts. These results demonstrate that Sharp-1 regulates muscle regenerative capacity, at least in part, by modulation of TGF-β signaling.

  3. Antioxidant Functions of the Aryl Hydrocarbon Receptor

    Directory of Open Access Journals (Sweden)

    Cornelia Dietrich

    2016-01-01

    Full Text Available The aryl hydrocarbon receptor (AhR is a transcription factor belonging to the basic helix-loop-helix/PER-ARNT-SIM family. It is activated by a variety of ligands, such as environmental contaminants like polycyclic aromatic hydrocarbons or dioxins, but also by naturally occurring compounds and endogenous ligands. Binding of the ligand leads to dimerization of the AhR with aryl hydrocarbon receptor nuclear translocator (ARNT and transcriptional activation of several xenobiotic phase I and phase II metabolizing enzymes. It is generally accepted that the toxic responses of polycyclic aromatic hydrocarbons, dioxins, and structurally related compounds are mediated by activation of the AhR. A multitude of studies indicate that the AhR operates beyond xenobiotic metabolism and exerts pleiotropic functions. Increasing evidence points to a protective role of the AhR against carcinogenesis and oxidative stress. Herein, I will highlight data demonstrating a causal role of the AhR in the antioxidant response and present novel findings on potential AhR-mediated antioxidative mechanisms.

  4. HES1 Is a Master Regulator of Glucocorticoid Receptor-Dependent Gene Expression

    Science.gov (United States)

    Revollo, Javier R.; Oakley, Robert H.; Lu, Nick Z.; Kadmiel, Mahita; Gandhavadi, Maheer; Cidlowski, John A.

    2014-01-01

    Hairy and enhancer of split-1 (HES1) is a basic helix-loop-helix transcription factor that is a key regulator of development and organogenesis. However, little is known about the role of HES1 after birth. Glucocorticoids, primary stress hormones that are essential for life, regulate numerous homeostatic processes that permit vertebrates to cope with physiological challenges. The molecular actions of glucocorticoids are mediated by glucocorticoid receptor-dependent regulation of nearly 25% of the genome. We now establish a genome wide molecular link between HES1 and glucocorticoid receptors that controls the ability of cells and animals to respond to stress. Glucocorticoid signaling rapidly and robustly silenced HES1 expression. This glucocorticoid-dependent repression of HES1 was necessary for the glucocorticoid receptor to regulate many of its target genes. Mice with conditional knockout of HES1 in the liver exhibited an expanded glucocorticoid receptor signaling profile and aberrant metabolic phenotype. Our results indicate that HES1 acts as a master repressor, the silencing of which is required for proper glucocorticoid signaling. PMID:24300895

  5. A functional genomics strategy reveals clockwork orange as a transcriptional regulator in the Drosophila circadian clock.

    Science.gov (United States)

    Matsumoto, Akira; Ukai-Tadenuma, Maki; Yamada, Rikuhiro G; Houl, Jerry; Uno, Kenichiro D; Kasukawa, Takeya; Dauwalder, Brigitte; Itoh, Taichi Q; Takahashi, Kuniaki; Ueda, Ryu; Hardin, Paul E; Tanimura, Teiichi; Ueda, Hiroki R

    2007-07-01

    The Drosophila circadian clock consists of integrated autoregulatory feedback loops, making the clock difficult to elucidate without comprehensively identifying the network components in vivo. Previous studies have adopted genome-wide screening for clock-controlled genes using high-density oligonucleotide arrays that identified hundreds of clock-controlled genes. In an attempt to identify the core clock genes among these candidates, we applied genome-wide functional screening using an RNA interference (RNAi) system in vivo. Here we report the identification of novel clock gene candidates including clockwork orange (cwo), a transcriptional repressor belonging to the basic helix-loop-helix ORANGE family. cwo is rhythmically expressed and directly regulated by CLK-CYC through canonical E-box sequences. A genome-wide search for its target genes using the Drosophila genome tiling array revealed that cwo forms its own negative feedback loop and directly suppresses the expression of other clock genes through the E-box sequence. Furthermore, this negative transcriptional feedback loop contributes to sustaining a high-amplitude circadian oscillation in vivo. Based on these results, we propose that the competition between cyclic CLK-CYC activity and the adjustable threshold imposed by CWO keeps E-box-mediated transcription within the controllable range of its activity, thereby rendering a Drosophila circadian clock capable of generating high-amplitude oscillation.

  6. The Stepwise Increase in the Number of Transcription Factor Families in the Precambrian Predated the Diversification of Plants On Land.

    Science.gov (United States)

    Catarino, Bruno; Hetherington, Alexander J; Emms, David M; Kelly, Steven; Dolan, Liam

    2016-11-01

    The colonization of the land by streptophytes and their subsequent radiation is a major event in Earth history. We report a stepwise increase in the number of transcription factor (TF) families and subfamilies in Archaeplastida before the colonization of the land. The subsequent increase in TF number on land was through duplication within existing TF families and subfamilies. Almost all subfamilies of the Homeodomain (HD) and basic Helix-Loop-Helix (bHLH) had evolved before the radiation of extant land plant lineages from a common ancestor. We demonstrate that the evolution of these TF families independently followed similar trends in both plants and metazoans; almost all extant HD and bHLH subfamilies were present in the first land plants and in the last common ancestor of bilaterians. These findings reveal that the majority of innovation in plant and metazoan TF families occurred in the Precambrian before the Phanerozoic radiation of land plants and metazoans. © The Author 2016. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  7. Mesogenin 1 is a master regulator of paraxial presomitic mesoderm differentiation

    Science.gov (United States)

    Chalamalasetty, Ravindra B.; Garriock, Robert J.; Dunty, William C.; Kennedy, Mark W.; Jailwala, Parthav; Si, Han; Yamaguchi, Terry P.

    2014-01-01

    Neuromesodermal (NM) stem cells generate neural and paraxial presomitic mesoderm (PSM) cells, which are the respective progenitors of the spinal cord and musculoskeleton of the trunk and tail. The Wnt-regulated basic helix-loop-helix (bHLH) transcription factor mesogenin 1 (Msgn1) has been implicated as a cooperative regulator working in concert with T-box genes to control PSM formation in zebrafish, although the mechanism is unknown. We show here that, in mice, Msgn1 alone controls PSM differentiation by directly activating the transcriptional programs that define PSM identity, epithelial-mesenchymal transition, motility and segmentation. Forced expression of Msgn1 in NM stem cells in vivo reduced the contribution of their progeny to the neural tube, and dramatically expanded the unsegmented mesenchymal PSM while blocking somitogenesis and notochord differentiation. Expression of Msgn1 was sufficient to partially rescue PSM differentiation in Wnt3a−/− embryos, demonstrating that Msgn1 functions downstream of Wnt3a as the master regulator of PSM differentiation. Our data provide new insights into how cell fate decisions are imposed by the expression of a single transcriptional regulator. PMID:25371364

  8. The mesenchymal architecture of the cranial mesoderm of mouse embryos is disrupted by the loss of Twist1 function.

    Science.gov (United States)

    Bildsoe, Heidi; Loebel, David A F; Jones, Vanessa J; Hor, Angelyn C C; Braithwaite, Antony W; Chen, You-Tzung; Behringer, Richard R; Tam, Patrick P L

    2013-02-15

    The basic helix-loop-helix transcription factor Twist1 is a key regulator of craniofacial development. Twist1-null mouse embryos exhibit failure of cephalic neural tube closure and abnormal head development and die at E11.0. To dissect the function of Twist1 in the cranial mesoderm beyond mid-gestation, we used Mesp1-Cre to delete Twist1 in the anterior mesoderm, which includes the progenitors of the cranial mesoderm. Deletion of Twist1 in mesoderm cells resulted in loss and malformations of the cranial mesoderm-derived skeleton. Loss of Twist1 in the mesoderm also resulted in a failure to fully segregate the mesoderm and the neural crest cells, and the malformation of some cranial neural crest-derived tissues. The development of extraocular muscles was compromised whereas the differentiation of branchial arch muscles was not affected, indicating a differential requirement for Twist1 in these two types of craniofacial muscle. A striking effect of the loss of Twist1 was the inability of the mesodermal cells to maintain their mesenchymal characteristics, and the acquisition of an epithelial-like morphology. Our findings point to a role of Twist1 in maintaining the mesenchyme architecture and the progenitor state of the mesoderm, as well as mediating mesoderm-neural crest interactions in craniofacial development. Copyright © 2012 Elsevier Inc. All rights reserved.

  9. Elicitor-induced transcription factors for metabolic reprogramming of secondary metabolism in Medicago truncatula

    Directory of Open Access Journals (Sweden)

    Dixon Richard A

    2008-12-01

    Full Text Available Abstract Background Exposure of Medicago truncatula cell suspension cultures to pathogen or wound signals leads to accumulation of various classes of flavonoid and/or triterpene defense molecules, orchestrated via a complex signalling network in which transcription factors (TFs are essential components. Results In this study, we analyzed TFs responding to yeast elicitor (YE or methyl jasmonate (MJ. From 502 differentially expressed TFs, WRKY and AP2/EREBP gene families were over-represented among YE-induced genes whereas Basic Helix-Loop-Helix (bHLH family members were more over-represented among the MJ-induced genes. Jasmonate ZIM-domain (JAZ transcriptional regulators were highly induced by MJ treatment. To investigate potential involvement of WRKY TFs in signalling, we expressed four Medicago WRKY genes in tobacco. Levels of soluble and wall bound phenolic compounds and lignin were increased in all cases. WRKY W109669 also induced tobacco endo-1,3-β-glucanase (NtPR2 and enhanced the systemic defense response to tobacco mosaic virus in transgenic tobacco plants. Conclusion These results confirm that Medicago WRKY TFs have broad roles in orchestrating metabolic responses to biotic stress, and that they also represent potentially valuable reagents for engineering metabolic changes that impact pathogen resistance.

  10. Roles of bHLH genes in neural stem cell differentiation

    International Nuclear Information System (INIS)

    Kageyama, Ryoichiro; Ohtsuka, Toshiyuki; Hatakeyama, Jun; Ohsawa, Ryosuke

    2005-01-01

    Neural stem cells change their characteristics over time during development: they initially proliferate only and then give rise to neurons first and glial cells later. In the absence of the repressor-type basic helix-loop-helix (bHLH) genes Hes1, Hes3 and Hes5, neural stem cells do not proliferate sufficiently but prematurely differentiate into neurons and become depleted without making the later born cell types such as astrocytes and ependymal cells. Thus, Hes genes are essential for maintenance of neural stem cells to make cells not only in correct numbers but also in full diversity. Hes genes antagonize the activator-type bHLH genes, which include Mash1, Math and Neurogenin. The activator-type bHLH genes promote the neuronal fate determination and induce expression of Notch ligands such as Delta. These ligands activate Notch signaling and upregulate Hes1 and Hes5 expression in neighboring cells, thereby maintaining these cells undifferentiated. Thus, the activator-type and repressor-type bHLH genes regulate each other, allowing only subsets of cells to undergo differentiation while keeping others to stay neural stem cells. This regulation is essential for generation of complex brain structures of appropriate size, shape and cell arrangement

  11. Origins and Evolution of Stomatal Development1[OPEN

    Science.gov (United States)

    2017-01-01

    The fossil record suggests stomata-like pores were present on the surfaces of land plants over 400 million years ago. Whether stomata arose once or whether they arose independently across newly evolving land plant lineages has long been a matter of debate. In Arabidopsis, a genetic toolbox has been identified that tightly controls stomatal development and patterning. This includes the basic helix-loop-helix (bHLH) transcription factors SPEECHLESS (SPCH), MUTE, FAMA, and ICE/SCREAMs (SCRMs), which promote stomatal formation. These factors are regulated via a signaling cascade, which includes mobile EPIDERMAL PATTERNING FACTOR (EPF) peptides to enforce stomatal spacing. Mosses and hornworts, the most ancient extant lineages to possess stomata, possess orthologs of these Arabidopsis (Arabidopsis thaliana) stomatal toolbox genes, and manipulation in the model bryophyte Physcomitrella patens has shown that the bHLH and EPF components are also required for moss stomatal development and patterning. This supports an ancient and tightly conserved genetic origin of stomata. Here, we review recent discoveries and, by interrogating newly available plant genomes, we advance the story of stomatal development and patterning across land plant evolution. Furthermore, we identify potential orthologs of the key toolbox genes in a hornwort, further supporting a single ancient genetic origin of stomata in the ancestor to all stomatous land plants. PMID:28356502

  12. Origins and Evolution of Stomatal Development.

    Science.gov (United States)

    Chater, Caspar C C; Caine, Robert S; Fleming, Andrew J; Gray, Julie E

    2017-06-01

    The fossil record suggests stomata-like pores were present on the surfaces of land plants over 400 million years ago. Whether stomata arose once or whether they arose independently across newly evolving land plant lineages has long been a matter of debate. In Arabidopsis, a genetic toolbox has been identified that tightly controls stomatal development and patterning. This includes the basic helix-loop-helix (bHLH) transcription factors SPEECHLESS ( SPCH ), MUTE , FAMA , and ICE/SCREAMs ( SCRMs ), which promote stomatal formation. These factors are regulated via a signaling cascade, which includes mobile EPIDERMAL PATTERNING FACTOR ( EPF ) peptides to enforce stomatal spacing. Mosses and hornworts, the most ancient extant lineages to possess stomata, possess orthologs of these Arabidopsis ( Arabidopsis thaliana ) stomatal toolbox genes, and manipulation in the model bryophyte Physcomitrella patens has shown that the bHLH and EPF components are also required for moss stomatal development and patterning. This supports an ancient and tightly conserved genetic origin of stomata. Here, we review recent discoveries and, by interrogating newly available plant genomes, we advance the story of stomatal development and patterning across land plant evolution. Furthermore, we identify potential orthologs of the key toolbox genes in a hornwort, further supporting a single ancient genetic origin of stomata in the ancestor to all stomatous land plants. © 2017 American Society of Plant Biologists. All Rights Reserved.

  13. Arabidopsis thaliana ICE2 gene: phylogeny, structural evolution and functional diversification from ICE1.

    Science.gov (United States)

    Kurbidaeva, Amina; Ezhova, Tatiana; Novokreshchenova, Maria

    2014-12-01

    The ability to tolerate environmental stresses is crucial for all living organisms, and gene duplication is one of the sources for evolutionary novelties. Arabidopsis thaliana INDUCER OF CBF EXPRESSION1 and 2 (ICE1 and ICE2) encode MYC-type bHLH (basic helix-loop-helix) transcription factors. They confer cold stress tolerance by induction of the CBF/DREB1 regulon and regulate stomata formation. Although ICE2 is closely related to ICE1, its origin and role in cold response remains uncertain. Here, we used a bioinformatics/phylogenetic approach to uncover the ICE2 evolutionary history, structural evolution and functional divergence from the putative ancestral gene. Sequence diversification from ICE1 included the gain of cis-acting elements in ICE2 promoter sequence that may provide meristem-specific and defense-related gene expression. By analyzing transgenic Arabidopsis lines with ICE2 over-expression we showed that it contributes to stomata formation, flowering time regulation and cold response. Constitutive ICE2 expression led to induced meristem freezing tolerance, resulting from activation of CBF1 and CBF3 genes and ABA biosynthesis by NCED3 induction. We presume that ICE2 gene has originated from a duplication event about 17.9MYA followed by sub- and neofunctionalization of the ancestral ICE1 gene. Moreover, we predict its role in pathogen resistance and flowering time regulation. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  14. Pod-1/Capsulin shows a sex- and stage-dependent expression pattern in the mouse gonad development and represses expression of Ad4BP/SF-1.

    Science.gov (United States)

    Tamura, M; Kanno, Y; Chuma, S; Saito, T; Nakatsuji, N

    2001-04-01

    Mammalian sex-determination and differentiation are controlled by several genes, such as Sry, Sox-9, Dax-1 and Mullerian inhibiting substance (MIS), but their upstream and downstream genes are largely unknown. Ad4BP/SF-1, encoding a zinc finger transcription factor, plays important roles in gonadogenesis. Disruption of this gene caused disappearance of the urogenital system including the gonad. Ad4BP/SF-1, however, is also involved in the sex differentiation of the gonad at later stages, such as the regulation of steroid hormones and MIS. Pod-1/Capsulin, a member of basic helix-loop-helix transcription factors, is expressed in a pattern closely related but mostly complimentary to that of the Ad4BP/SF-1 expression in the developing gonad. In the co-transfection experiment using cultured cells, overexpression of Pod-1/Capsulin repressed expression of a reporter gene that carried the upstream regulatory region of the Ad4BP/SF-1 gene. Furthermore, forced expression of Pod-1/Capsulin repressed expression of Ad4BP/SF-1 in the Leydig cell-derived I-10 cells. These results suggest that Pod-1/Capsulin may play important roles in the development and sex differentiation of the mammalian gonad via transcriptional regulation of Ad4BP/SF-1.

  15. The Role of Atoh1 in Mucous Cell Metaplasia

    Directory of Open Access Journals (Sweden)

    Yoshihisa Nakamura

    2012-01-01

    Full Text Available A key issue in otitis media is mucous cell metaplasia which is responsible for mucous hypersecretion and persistence of the disease. However, little is known about the molecular mechanisms of mucous cell metaplasia in otitis media. Numerous studies of intestinal epithelial homeostasis have shown that Atonal homolog 1 (Atoh1, a basic helix-loop-helix (bHLH transcription factor, is essential for the intestinal goblet cell differentiation. On the other hand, SAM-pointed domain-containing Ets transcription factor (SPDEF, a member of the “Ets” transcription factor family, has been reported to trigger the mucous cell metaplasia of pulmonary infectious diseases or athsma. Recent studies have demonstrated the relation of these factors, that is, Spdef functions downstream of Atoh1. We could take the adventages of these findings for the study of otitis media because both middle ear and pulmonary epithelia belong to the same respiratory tract. Atoh1 and SPDEF could be the therapeutic targets for otitis media associated with mucous cell metaplasia which is frequently considered “intractable” in the clinical settings.

  16. Structure of the Cpf1 endonuclease R-loop complex after target DNA cleavage

    DEFF Research Database (Denmark)

    Stella, Stefano; Alcón, Pablo; Montoya, Guillermo

    2017-01-01

    involved in DNA unwinding to form a CRISPR RNA (crRNA)-DNA hybrid and a displaced DNA strand. The protospacer adjacent motif (PAM) is recognized by the PAM-interacting domain. The loop-lysine helix-loop motif in this domain contains three conserved lysine residues that are inserted in a dentate manner...... into the double-stranded DNA. Unzipping of the double-stranded DNA occurs in a cleft arranged by acidic and hydrophobic residues facilitating the crRNA-DNA hybrid formation. The PAM single-stranded DNA is funnelled towards the nuclease site through a mixed hydrophobic and basic cavity. In this catalytic...... conformation, the PAM-interacting domain and the helix-loop-helix motif in the REC1 domain adopt a 'rail' shape and 'flap-on' conformations, respectively, channelling the PAM strand into the cavity. A steric barrier between the RuvC-II and REC1 domains forms the 'septum', separating the displaced PAM strand...

  17. Hierarchical axon targeting of Drosophila olfactory receptor neurons specified by the proneural transcription factors Atonal and Amos.

    Science.gov (United States)

    Okumura, Misako; Kato, Tomoko; Miura, Masayuki; Chihara, Takahiro

    2016-01-01

    Sensory information is spatially represented in the brain to form a neural map. It has been suggested that axon-axon interactions are important for neural map formation; however, the underlying mechanisms are not fully understood. We used the Drosophila antennal lobe, the first olfactory center in the brain, as a model for studying neural map formation. Olfactory receptor neurons (ORNs) expressing the same odorant receptor target their axons to a single glomerulus out of approximately 50 glomeruli in the antennal lobe. Previous studies have showed that the axons of Atonal ORNs, specified by Atonal, a basic helix-loop-helix (bHLH) transcription factor, pioneer antennal lobe formation; however, the details remain to be elucidated. Here, we show that genetic ablation of Atonal ORNs affects antennal lobe structure and axon targeting of Amos ORNs, another type of ORN specified by the bHLH transcription factor Amos. During development, Atonal ORNs reach the antennal lobe and form the axon commissure before Amos ORNs. We also found that N-cadherin knockdown specifically in Atonal ORNs disrupts the glomerular boundary in the whole antennal lobe. Our results suggest that Atonal ORNs function as pioneer axons. Thus, correct axon targeting of Atonal ORNs is essential for formation of the whole antennal lobe. © 2015 The Molecular Biology Society of Japan and Wiley Publishing Asia Pty Ltd.

  18. Arabidopsis HFR1 is a potential nuclear substrate regulated by the Xanthomonas type III effector XopD(Xcc8004.

    Directory of Open Access Journals (Sweden)

    Choon Meng Tan

    Full Text Available XopDXcc8004, a type III effector of Xanthomonas campestris pv. campestris (Xcc 8004, is considered a shorter version of the XopD, which lacks the N-terminal domain. To understand the functions of XopDXcc8004, in planta, a transgenic approach combined with inducible promoter to analyze the effects of XopDXcc8004 in Arabidopsis was done. Here, the expression of XopDXcc8004, in Arabidopsis elicited the accumulation of host defense-response genes. These molecular changes were dependent on salicylic acid and correlated with lesion-mimic phenotypes observed in XVE::XopDXcc8004 transgenic plants. Moreover, XopDXcc8004 was able to desumoylate HFR1, a basic helix-loop-helix transcription factor involved in photomorphogenesis, through SUMO protease activity. Interestingly, the hfr1-201 mutant increased the expression of host defense-response genes and displayed a resistance phenotype to Xcc8004. These data suggest that HFR1 is involved in plant innate immunity and is potentially regulated by XopDXcc8004.

  19. The Transcriptional Repressor MYB2 Regulates Both Spatial and Temporal Patterns of Proanthocyandin and Anthocyanin Pigmentation in Medicago truncatula[OPEN

    Science.gov (United States)

    2015-01-01

    Accumulation of anthocyanins and proanthocyanidins (PAs) is limited to specific cell types and developmental stages, but little is known about how antagonistically acting transcriptional regulators work together to determine temporal and spatial patterning of pigmentation at the cellular level, especially for PAs. Here, we characterize MYB2, a transcriptional repressor regulating both anthocyanin and PA biosynthesis in the model legume Medicago truncatula. MYB2 was strongly upregulated by MYB5, a major regulator of PA biosynthesis in M. truncatula and a component of MYB-basic helix loop helix-WD40 (MBW) activator complexes. Overexpression of MYB2 abolished anthocyanin and PA accumulation in M. truncatula hairy roots and Arabidopsis thaliana seeds, respectively. Anthocyanin deposition was expanded in myb2 mutant seedlings and flowers accompanied by increased anthocyanin content. PA mainly accumulated in the epidermal layer derived from the outer integument in the M. truncatula seed coat, starting from the hilum area. The area of PA accumulation and ANTHOCYANIDIN REDUCTASE expression was expanded into the seed body at the early stage of seed development in the myb2 mutant. Genetic, biochemical, and cell biological evidence suggests that MYB2 functions as part of a multidimensional regulatory network to define the temporal and spatial pattern of anthocyanin and PA accumulation linked to developmental processes. PMID:26410301

  20. The Transcriptional Repressor MYB2 Regulates Both Spatial and Temporal Patterns of Proanthocyandin and Anthocyanin Pigmentation in Medicago truncatula.

    Science.gov (United States)

    Jun, Ji Hyung; Liu, Chenggang; Xiao, Xirong; Dixon, Richard A

    2015-10-01

    Accumulation of anthocyanins and proanthocyanidins (PAs) is limited to specific cell types and developmental stages, but little is known about how antagonistically acting transcriptional regulators work together to determine temporal and spatial patterning of pigmentation at the cellular level, especially for PAs. Here, we characterize MYB2, a transcriptional repressor regulating both anthocyanin and PA biosynthesis in the model legume Medicago truncatula. MYB2 was strongly upregulated by MYB5, a major regulator of PA biosynthesis in M. truncatula and a component of MYB-basic helix loop helix-WD40 (MBW) activator complexes. Overexpression of MYB2 abolished anthocyanin and PA accumulation in M. truncatula hairy roots and Arabidopsis thaliana seeds, respectively. Anthocyanin deposition was expanded in myb2 mutant seedlings and flowers accompanied by increased anthocyanin content. PA mainly accumulated in the epidermal layer derived from the outer integument in the M. truncatula seed coat, starting from the hilum area. The area of PA accumulation and ANTHOCYANIDIN REDUCTASE expression was expanded into the seed body at the early stage of seed development in the myb2 mutant. Genetic, biochemical, and cell biological evidence suggests that MYB2 functions as part of a multidimensional regulatory network to define the temporal and spatial pattern of anthocyanin and PA accumulation linked to developmental processes. © 2015 American Society of Plant Biologists. All rights reserved.

  1. CD26-mediated regulation of periostin expression contributes to migration and invasion of malignant pleural mesothelioma cells

    Energy Technology Data Exchange (ETDEWEB)

    Komiya, Eriko [Department of Therapy Development and Innovation for Immune Disorders and Cancers, Graduate School of Medicine, Juntendo University, 2-1-1, Hongo, Bunkyo-ku, Tokyo 113-8421 (Japan); Ohnuma, Kei, E-mail: kohnuma@juntendo.ac.jp [Department of Therapy Development and Innovation for Immune Disorders and Cancers, Graduate School of Medicine, Juntendo University, 2-1-1, Hongo, Bunkyo-ku, Tokyo 113-8421 (Japan); Yamazaki, Hiroto; Hatano, Ryo; Iwata, Satoshi; Okamoto, Toshihiro [Department of Therapy Development and Innovation for Immune Disorders and Cancers, Graduate School of Medicine, Juntendo University, 2-1-1, Hongo, Bunkyo-ku, Tokyo 113-8421 (Japan); Dang, Nam H. [Division of Hematology/Oncology, University of Florida, 1600 SW Archer Road, Box 100278, Room MSB M410A, Gainesville, FL 32610 (United States); Yamada, Taketo [Department of Pathology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582 (Japan); Morimoto, Chikao [Department of Therapy Development and Innovation for Immune Disorders and Cancers, Graduate School of Medicine, Juntendo University, 2-1-1, Hongo, Bunkyo-ku, Tokyo 113-8421 (Japan)

    2014-05-16

    Highlights: • CD26-expressing MPM cells upregulate production of periostin. • The intracytoplasmic region of CD26 mediates the upregulation of periostin. • CD26 expression leads to nuclear translocation of Twist1 via phosphorylation of Src. • Secreted periostin enhances migration and invasion of MPM cells. - Abstract: Malignant pleural mesothelioma (MPM) is an aggressive malignancy arising from mesothelial lining of pleura. It is generally associated with a history of asbestos exposure and has a very poor prognosis, partly due to the lack of a precise understanding of the molecular mechanisms associated with its malignant behavior. In the present study, we expanded on our previous studies on the enhanced motility and increased CD26 expression in MPM cells, with a particular focus on integrin adhesion molecules. We found that expression of CD26 upregulates periostin secretion by MPM cells, leading to enhanced MPM cell migratory and invasive activity. Moreover, we showed that upregulation of periostin expression results from the nuclear translocation of the basic helix-loop-helix transcription factor Twist1, a process that is mediated by CD26-associated activation of Src phosphorylation. While providing new and profound insights into the molecular mechanisms involved in MPM biology, these findings may also lead to the development of novel therapeutic strategies for MPM.

  2. The window period of NEUROGENIN3 during human gestation.

    Science.gov (United States)

    Salisbury, Rachel J; Blaylock, Jennifer; Berry, Andrew A; Jennings, Rachel E; De Krijger, Ronald; Piper Hanley, Karen; Hanley, Neil A

    2014-01-01

    The basic helix-loop-helix transcription factor, NEUROG3, is critical in causing endocrine commitment from a progenitor cell population in the developing pancreas. In human, NEUROG3 has been detected from 8 weeks post-conception (wpc). However, the profile of its production and when it ceases to be detected is unknown. In this study we have defined the profile of NEUROG3 detection in the developing pancreas to give insight into when NEUROG3-dependent endocrine commitment is possible in the human fetus. Immunohistochemistry allowed counting of cells with positively stained nuclei from 7 wpc through to term. mRNA was also isolated from sections of human fetal pancreas and NEUROG3 transcription analyzed by quantitative reverse transcription and polymerase chain reaction. NEUROG3 was detected as expected at 8 wpc. The number of NEUROG3-positive cells increased to peak levels between 10 wpc and 14 wpc. It declined at and after 18 wpc such that it was not detected in human fetal pancreas at 35-41 wpc. Analysis of NEUROG3 transcription corroborated this profile by demonstrating very low levels of transcript at 35-41 wpc, more than 10-fold lower than levels at 12-16 wpc. These data define the appearance, peak and subsequent disappearance of the critical transcription factor, NEUROG3, in human fetal pancreas for the first time. By inference, the window for pancreatic endocrine differentiation via NEUROG3 action opens at 8 wpc and closes between 21 and 35 wpc.

  3. Overexpression of a transcription factor LYL1 induces T- and B-cell lymphoma in mice.

    Science.gov (United States)

    Zhong, Y; Jiang, L; Hiai, H; Toyokuni, S; Yamada, Y

    2007-10-18

    LYL1, a member of the class II basic helix-loop-helix transcription factors, is aberrantly expressed in a fraction of human T-cell acute lymphoblastic leukemia. Here, we generated transgenic mice ubiquitously overexpressing LYL1 using a construct expressing full-length cDNA driven by a human elongation factor 1alpha promoter. Four independent lines exhibiting high LYL1 expression were established. Of these transgenic mice, 96% displayed loss of hair with a short kinked tail. Furthermore, 30% of them developed malignant lymphoma, with an average latent period of 352 days. In these mice, histological examination revealed tumor cell infiltration in multiple organs and immunohistochemical analysis showed that the infiltrated tumor cells were either CD3 or CD45R/B220-positive; fluorescence-activated cell sorter analysis indicated that each tumor consisted either of mainly CD4, CD8 double-positive T cells or mature B cells; the clonality of LYL1-induced lymphoma was confirmed by T-cell receptor rearrangement and immunoglobulin heavy-chain gene rearrangement analyses. Mammalian two-hybrid analysis and luciferase assay suggested that excess LYL1 blocked the dimerization of E2A and thus inhibited the regulatory activity of E2A on the CD4 promoter. Reverse transcription-polymerase chain reaction results showed that the expression of certain E2A/HEB target genes was downregulated. Taken together, our results provide direct evidence that aberrant expression of LYL1 plays a role in lymphomagenesis.

  4. Twist1 promotes heart valve cell proliferation and extracellular matrix gene expression during development in vivo and is expressed in human diseased aortic valves

    Science.gov (United States)

    Chakraborty, Santanu; Wirrig, Elaine E.; Hinton, Robert B.; Merrill, Walter H.; Spicer, Douglas B.; Yutzey, Katherine E.

    2010-01-01

    During embryogenesis the heart valves develop from undifferentiated mesenchymal endocardial cushions (EC), and activated interstitial cells of adult diseased valves share characteristics of embryonic valve progenitors. Twist1, a class II basic-helix-loop-helix (bHLH) transcription factor, is expressed during early EC development and is downregulated later during valve remodeling. The requirements for Twist1 down-regulation in the remodeling valves and the consequences of prolonged Twist1 activity were examined in transgenic mice with persistent expression of Twist1 in developing and mature valves. Persistent Twist1 expression in the remodeling valves leads to increased valve cell proliferation, increased expression of Tbx20, and increased extracellular matrix (ECM) gene expression, characteristic of early valve progenitors. Among the ECM genes predominant in the EC, Col2a1 was identified as a direct transcriptional target of Twist1. Increased Twist1 expression also leads to dysregulation of fibrillar collagen and periostin expression, as well as enlarged hypercellular valve leaflets prior to birth. In human diseased aortic valves, increased Twist1 expression and cell proliferation are observed adjacent to nodules of calcification. Overall, these data implicate Twist1 as a critical regulator of valve development and suggest that Twist1 influences ECM production and cell proliferation during disease. PMID:20804746

  5. Ebf1 controls early cell differentiation in the embryonic striatum.

    Science.gov (United States)

    Garel, S; Marín, F; Grosschedl, R; Charnay, P

    1999-12-01

    Ebf1/Olf-1 belongs to a small multigene family encoding closely related helix-loop-helix transcription factors, which have been proposed to play a role in neuronal differentiation. Here we show that Ebf1 controls cell differentiation in the murine embryonic striatum, where it is the only gene of the family to be expressed. Ebf1 targeted disruption affects postmitotic cells that leave the subventricular zone (SVZ) en route to the mantle: they appear to be unable to downregulate genes normally restricted to the SVZ or to activate some mantle-specific genes. These downstream genes encode a variety of regulatory proteins including transcription factors and proteins involved in retinoid signalling as well as adhesion/guidance molecules. These early defects in the SVZ/mantle transition are followed by an increase in cell death, a dramatic reduction in size of the postnatal striatum and defects in navigation and fasciculation of thalamocortical fibres travelling through the striatum. Our data therefore show that Ebf1 plays an essential role in the acquisition of mantle cell molecular identity in the developing striatum and provide information on the genetic hierarchies that govern neuronal differentiation in the ventral telencephalon.

  6. Basic Electromagnetism and Materials

    CERN Document Server

    Moliton, André

    2007-01-01

    Basic Electromagnetism and Materials is the product of many years of teaching basic and applied electromagnetism. This textbook can be used to teach electromagnetism to a wide range of undergraduate science majors in physics, electrical engineering or materials science. However, by making lesser demands on mathematical knowledge than competing texts, and by emphasizing electromagnetic properties of materials and their applications, this textbook is uniquely suited to students of materials science. Many competing texts focus on the study of propagation waves either in the microwave or optical domain, whereas Basic Electromagnetism and Materials covers the entire electromagnetic domain and the physical response of materials to these waves. Professor André Moliton is Director of the Unité de Microélectronique, Optoélectronique et Polymères (Université de Limoges, France), which brings together three groups studying the optoelectronics of molecular and polymer layers, micro-optoelectronic systems for teleco...

  7. Comprehensive basic mathematics

    CERN Document Server

    Veena, GR

    2005-01-01

    Salient Features As per II PUC Basic Mathematics syllabus of Karnataka. Provides an introduction to various basic mathematical techniques and the situations where these could be usefully employed. The language is simple and the material is self-explanatory with a large number of illustrations. Assists the reader in gaining proficiency to solve diverse variety of problems. A special capsule containing a gist and list of formulae titled ''REMEMBER! Additional chapterwise arranged question bank and 3 model papers in a separate section---''EXAMINATION CORNER''.

  8. Basic Financial Accounting

    DEFF Research Database (Denmark)

    Wiborg, Karsten

    This textbook on Basic Financial Accounting is targeted students in the economics studies at universities and business colleges having an introductory subject in the external dimension of the company's economic reporting, including bookkeeping, etc. The book includes the following subjects: busin......: business entities, the transformation process, types of businesses, stakeholders, legislation, the annual report, the VAT system, double-entry bookkeeping, inventories, and year-end cast flow analysis.......This textbook on Basic Financial Accounting is targeted students in the economics studies at universities and business colleges having an introductory subject in the external dimension of the company's economic reporting, including bookkeeping, etc. The book includes the following subjects...

  9. Ecology and basic laws

    International Nuclear Information System (INIS)

    Mayer-Tasch, P.C.

    1980-01-01

    The author sketches the critical relation between ecology and basic law - critical in more than one sense. He points out the incompatibility of constitutional states and atomic states which is due to constitutional order being jeopardised by nuclear policy. He traces back the continuously rising awareness of pollution and the modern youth movement to their common root i.e. the awakening, the youth movement of the turn of the century. Eventually, he considers an economical, political, and social decentralization as a feasible alternative which would considerably relieve our basic living conditions from the threatening forms of civilization prevailing. (HSCH) [de

  10. Basic set theory

    CERN Document Server

    Levy, Azriel

    2002-01-01

    An advanced-level treatment of the basics of set theory, this text offers students a firm foundation, stopping just short of the areas employing model-theoretic methods. Geared toward upper-level undergraduate and graduate students, it consists of two parts: the first covers pure set theory, including the basic motions, order and well-foundedness, cardinal numbers, the ordinals, and the axiom of choice and some of it consequences; the second deals with applications and advanced topics such as point set topology, real spaces, Boolean algebras, and infinite combinatorics and large cardinals. An

  11. Basic properties of semiconductors

    CERN Document Server

    Landsberg, PT

    2013-01-01

    Since Volume 1 was published in 1982, the centres of interest in the basic physics of semiconductors have shifted. Volume 1 was called Band Theory and Transport Properties in the first edition, but the subject has broadened to such an extent that Basic Properties is now a more suitable title. Seven chapters have been rewritten by the original authors. However, twelve chapters are essentially new, with the bulk of this work being devoted to important current topics which give this volume an almost encyclopaedic form. The first three chapters discuss various aspects of modern band theory and the

  12. Four genes essential for recombination define GInts, a new type of mobile genomic island widespread in bacteria.

    Science.gov (United States)

    Bardaji, Leire; Echeverría, Myriam; Rodríguez-Palenzuela, Pablo; Martínez-García, Pedro M; Murillo, Jesús

    2017-04-10

    Integrases are a family of tyrosine recombinases that are highly abundant in bacterial genomes, actively disseminating adaptive characters such as pathogenicity determinants and antibiotics resistance. Using comparative genomics and functional assays, we identified a novel type of mobile genetic element, the GInt, in many diverse bacterial groups but not in archaea. Integrated as genomic islands, GInts show a tripartite structure consisting of the ginABCD operon, a cargo DNA region from 2.5 to at least 70 kb, and a short AT-rich 3' end. The gin operon is characteristic of GInts and codes for three putative integrases and a small putative helix-loop-helix protein, all of which are essential for integration and excision of the element. Genes in the cargo DNA are acquired mostly from phylogenetically related bacteria and often code for traits that might increase fitness, such as resistance to antimicrobials or virulence. GInts also tend to capture clusters of genes involved in complex processes, such as the biosynthesis of phaseolotoxin by Pseudomonas syringae. GInts integrate site-specifically, generating two flanking direct imperfect repeats, and excise forming circular molecules. The excision process generates sequence variants at the element attachment site, which can increase frequency of integration and drive target specificity.

  13. Generation and characterization of neurogenin1-GFP transgenic medaka with potential for rapid developmental neurotoxicity screening

    International Nuclear Information System (INIS)

    Fan Chunyang; Simmons, Steven O.; Law, Sheran H.W.; Jensen, Karl; Cowden, John; Hinton, David; Padilla, Stephanie; Ramabhadran, Ram

    2011-01-01

    Fish models such as zebrafish and medaka are increasingly used as alternatives to rodents in developmental and toxicological studies. These developmental and toxicological studies can be facilitated by the use of transgenic reporters that permit the real-time, noninvasive observation of the fish. Here we report the construction and characterization of transgenic medaka lines expressing green fluorescent protein (GFP) under the control of the zebrafish neurogenin 1 (ngn1) gene promoter. Neurogenin (ngn1) is a helix-loop-helix transcription factor expressed in proliferating neuronal progenitor cells early in neuronal differentiation and plays a crucial role in directing neurogenesis. GFP expression was detected from 24 h post-fertilization until hatching, in a spatial pattern consistent with the previously reported zebrafish ngn1 expression. Temporal expression of the transgene parallels the expression profile of the endogenous medaka ngn1 transcript. Further, we demonstrate that embryos from the transgenic line permit the non-destructive, real-time screening of ngn1 promoter-directed GFP expression in a 96-well format, enabling higher throughput studies of developmental neurotoxicants. This strain has been deposited with and maintained by the National BioResource Project and is available on request ( (http://www.shigen.nig.ac.jp/medaka/strainDetailAction.do?quickSearch=true and strainId=5660)).

  14. Twist2 Is Upregulated in Early Stages of Repair Following Acute Kidney Injury

    Directory of Open Access Journals (Sweden)

    Elizabeth A. Grunz-Borgmann

    2017-02-01

    Full Text Available The aging kidney is a marked by a number of structural and functional changes, including an increased susceptibility to acute kidney injury (AKI. Previous studies from our laboratory have shown that aging male Fischer 344 rats (24 month are more susceptible to apoptosis-mediated injury than young counterparts. In the current studies, we examined the initial injury and early recovery phases of mercuric chloride-induced AKI. Interestingly, the aging kidney had decreased serum creatinine compared to young controls 1 day following mercuric chloride injury, but by day 4, serum creatinine was significantly elevated, suggesting that the aging kidney did not recover from injury. This conclusion is supported by the findings that serum creatinine and kidney injury molecule-1 (Kim-1 gene expression remain elevated compared to young controls at 10 days post-injury. To begin to elucidate mechanism(s underlying dysrepair in the aging kidney, we examined the expression of Twist2, a helix-loop-helix transcription factor that may mediate renal fibrosis. Interestingly, Twist2 gene expression was elevated following injury in both young and aged rats, and Twist2 protein expression is elevated by mercuric chloride in vitro.

  15. Infrared study of synthetic peptide analogues of the calcium-binding site III of troponin C: The role of helix F of an EF-hand motif.

    Science.gov (United States)

    Nara, Masayuki; Morii, Hisayuki; Tanokura, Masaru

    2013-05-01

    The EF-hand motif (helix-loop-helix) is a Ca(2+)-binding domain that is common among many intracellular Ca(2+)-binding proteins. We applied Fourier-transform infrared spectroscopy to study the synthetic peptide analogues of site III of rabbit skeletal muscle troponin C (helix E-loop-helix F). The 17-residue peptides corresponding to loop-helix F (DRDADGYIDAEELAEIF), where one residue is substituted by the D-type amino acid, were investigated to disturb the α-helical conformation of helix F systematically. These D-type-substituted peptides showed no band at about 1555 cm(-1) even in the Ca(2+)-loaded state although the native peptide (L-type only) showed a band at about 1555 cm(-1) in the Ca(2+)-loaded state, which is assigned to the side-chain COO(-) group of Glu at the 12th position, serving as the ligand for Ca(2+) in the bidentate coordination mode. Therefore, helix F is vital to the interaction between the Ca(2+) and the side-chain COO(-) group of Glu at the 12th position. Implications of the COO(-) antisymmetric stretch and the amide-I' of the synthetic peptide analogues of the Ca(2+)-binding sites are discussed. Copyright © 2012 Wiley Periodicals, Inc.

  16. Treatment of experimental allergic encephalomyelitis (EAE) induced by guinea pig myelin basic protein epitope 72-85 with a human MBP(87-99) analogue and effects of cyclic peptides.

    Science.gov (United States)

    Tselios, T; Daliani, I; Probert, L; Deraos, S; Matsoukas, E; Roy, S; Pires, J; Moore, G; Matsoukas, J

    2000-08-01

    Experimental autoimmune encephalomyelitis (EAE) is an inflammatory and demyelinating disease of the central nervous system and is an animal model of multiple sclerosis (MS). In the present report, a linear analogue and a series of cyclic semi-mimetic peptides were designed and synthesized based on the human myelin basic protein (MBP(87-99)) epitope (Val87-His-Phe-Phe-Lys-Asn-Ile-Val-Thr-Pro-Arg-Thr-Pro90) and on Copolymer I (a mixture of random polymers of Ala, Gln, Lys and Tyr used to treat MS). These analogues were designed looking for suppressors of EAE induced by guinea pig MBP(72-85) epitope (Gln-Lys-Ser-Gln-Arg-Ser-Gln-Asp-Glu-Asn-Pro-Val) in Lewis rats. The linear analogue [Arg91,Ala96]MBP(87-99), in which Arg substitutes Lys91 and Ala substitutes Pro96, was found to be a strong inhibitor which when administered to Lewis rats together with the encephalitogenic agonist MBP(72-85) completely prevented the induction of EAE. In contrast, three N- and C-termini amide-linked cyclic semi-mimetic peptides, [cyclo-Phe-Arg-Asn-Ile-Val-Thr-Ala-Acp (1), cyclo-Phe-Ala-Arg-Gln-Acp (2), cyclo-Tyr-Ala-Lys-Gln-Acp (3)] as well as a Lys side chain and C-terminous cyclic semi mimetic peptide cyclo(Lys, Acp)-Phe-Lys-Asn-Ile-Val-Thr-Ala-Acp (4) which contain segments of MBP(87-99) or are constituted from immunophoric residues of copolymer 1, were ineffective in inducing or inhibiting EAE in Lewis rats. However co-injection of cyclic analogues with MBP(72-85) delayed the onset of EAE indicating a modulatory effect on the EAE activity of MBP(72-85). These findings suggest that molecule length, size of cyclic moiety and backbone conformation are important elements for immunogenic activity. Moreover blockade of MBP(72-85) induced EAE by the unrelated peptide [Arg91,Ala56]MBP(87-99) could indicate that the mechanism of inhibition is not due to binding competition but rather due to the delivery of a negative signal by the antagonist which overcomes the agonist response possibly

  17. Foundation of Basic Arithmetic

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 11; Issue 2. Foundation of Basic Arithmetic. Jasbir S Chahal. General Article Volume 11 Issue 2 February 2006 pp 6-16. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/011/02/0006-0016. Keywords. Different ...

  18. Basic Tuberculosis Facts

    Centers for Disease Control (CDC) Podcasts

    2012-03-12

    In this podcast, Dr. Kenneth Castro, Director of the Division of Tuberculosis Elimination, discusses basic TB prevention, testing, and treatment information.  Created: 3/12/2012 by National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention (NCHHSTP).   Date Released: 3/12/2012.

  19. Basics of SCI Rehabilitation

    Medline Plus

    Full Text Available ... Heather Taylor, PhD Michelle Meade, PhD Jonathon Rose, PhD The Basics of Spinal Cord Injury Rehabilitation Kristine Cichowski, ... Cord Injury Katie Powell, OT Mary Jane Mulcahey, PhD, OTR/L Sarah Harrison, OT Anne Bryden, OT The Role of the Social Worker after Spinal Cord ...

  20. Basic radiation oncology

    International Nuclear Information System (INIS)

    Beyzadeoglu, M. M.; Ebruli, C.

    2008-01-01

    Basic Radiation Oncology is an all-in-one book. It is an up-to-date bedside oriented book integrating the radiation physics, radiobiology and clinical radiation oncology. It includes the essentials of all aspects of radiation oncology with more than 300 practical illustrations, black and white and color figures. The layout and presentation is very practical and enriched with many pearl boxes. Key studies particularly randomized ones are also included at the end of each clinical chapter. Basic knowledge of all high-tech radiation teletherapy units such as tomotherapy, cyberknife, and proton therapy are also given. The first 2 sections review concepts that are crucial in radiation physics and radiobiology. The remaining 11 chapters describe treatment regimens for main cancer sites and tumor types. Basic Radiation Oncology will greatly help meeting the needs for a practical and bedside oriented oncology book for residents, fellows, and clinicians of Radiation, Medical and Surgical Oncology as well as medical students, physicians and medical physicists interested in Clinical Oncology. English Edition of the book Temel Radyasyon Onkolojisi is being published by Springer Heidelberg this year with updated 2009 AJCC Staging as Basic Radiation Oncology

  1. Basic physics for all

    CERN Document Server

    Kumar, B N

    2012-01-01

    This is a simple, concise book for both student and non-physics students, presenting basic facts in straightforward form and conveying fundamental principles and theories of physics. This book will be helpful as a supplement to class teaching and to aid those who have difficulty in mastering concepts and principles.

  2. Basic Electronics II.

    Science.gov (United States)

    Willison, Neal A.; Shelton, James K.

    Designed for use in basic electronics programs, this curriculum guide is comprised of 15 units of instruction. Unit titles are Review of the Nature of Matter and the P-N Junction, Rectifiers, Filters, Special Semiconductor Diodes, Bipolar-Junction Diodes, Bipolar Transistor Circuits, Transistor Amplifiers, Operational Amplifiers, Logic Devices,…

  3. Greek Basic Course.

    Science.gov (United States)

    Defense Language Inst., Washington, DC.

    This course in Modern Greek, consisting of 100 lesson units in 13 volumes, is one of the Defense Language Institute's Basic Course Series. The course is designed to train native English language speakers to Level 3 proficiency in comprehension, speaking, reading, and writing Modern Greek. (Level 5 is native-speaker proficiency.) Lesson units…

  4. Basic Self-Esteem.

    Science.gov (United States)

    Kaeter, Margaret

    1993-01-01

    Training employees in basic skills necessitates sensitivity to their self-esteem. This can be achieved if the organizational culture supports training, the program is voluntary, it uses the group's strengths, it challenges them on an adult level, it does not resemble traditional schooling, and it builds in quick success. (SK)

  5. Basic Exchange Rate Theories

    NARCIS (Netherlands)

    J.G.M. van Marrewijk (Charles)

    2005-01-01

    textabstractThis four-chapter overview of basic exchange rate theories discusses (i) the elasticity and absorption approach, (ii) the (long-run) implications of the monetary approach, (iii) the short-run effects of monetary and fiscal policy under various economic conditions, and (iv) the transition

  6. Ethanol Basics (Fact Sheet)

    Energy Technology Data Exchange (ETDEWEB)

    2015-01-01

    Ethanol is a widely-used, domestically-produced renewable fuel made from corn and other plant materials. More than 96% of gasoline sold in the United States contains ethanol. Learn more about this alternative fuel in the Ethanol Basics Fact Sheet, produced by the U.S. Department of Energy's Clean Cities program.

  7. Basic Soils. Revision.

    Science.gov (United States)

    Montana State Univ., Bozeman. Dept. of Agricultural and Industrial Education.

    This curriculum guide is designed for use in teaching a course in basic soils that is intended for college freshmen. Addressed in the individual lessons of the unit are the following topics: the way in which soil is formed, the physical properties of soil, the chemical properties of soil, the biotic properties of soil, plant-soil-water…

  8. Basics of statistical physics

    CERN Document Server

    Müller-Kirsten, Harald J W

    2013-01-01

    Statistics links microscopic and macroscopic phenomena, and requires for this reason a large number of microscopic elements like atoms. The results are values of maximum probability or of averaging. This introduction to statistical physics concentrates on the basic principles, and attempts to explain these in simple terms supplemented by numerous examples. These basic principles include the difference between classical and quantum statistics, a priori probabilities as related to degeneracies, the vital aspect of indistinguishability as compared with distinguishability in classical physics, the differences between conserved and non-conserved elements, the different ways of counting arrangements in the three statistics (Maxwell-Boltzmann, Fermi-Dirac, Bose-Einstein), the difference between maximization of the number of arrangements of elements, and averaging in the Darwin-Fowler method. Significant applications to solids, radiation and electrons in metals are treated in separate chapters, as well as Bose-Eins...

  9. Basics of RF electronics

    CERN Document Server

    Gallo, A

    2011-01-01

    RF electronics deals with the generation, acquisition and manipulation of high-frequency signals. In particle accelerators signals of this kind are abundant, especially in the RF and beam diagnostics systems. In modern machines the complexity of the electronics assemblies dedicated to RF manipulation, beam diagnostics, and feedbacks is continuously increasing, following the demands for improvement of accelerator performance. However, these systems, and in particular their front-ends and back-ends, still rely on well-established basic hardware components and techniques, while down-converted and acquired signals are digitally processed exploiting the rapidly growing computational capability offered by the available technology. This lecture reviews the operational principles of the basic building blocks used for the treatment of high-frequency signals. Devices such as mixers, phase and amplitude detectors, modulators, filters, switches, directional couplers, oscillators, amplifiers, attenuators, and others are d...

  10. Basic electronic circuits

    CERN Document Server

    Buckley, P M

    1980-01-01

    In the past, the teaching of electricity and electronics has more often than not been carried out from a theoretical and often highly academic standpoint. Fundamentals and basic concepts have often been presented with no indication of their practical appli­ cations, and all too frequently they have been illustrated by artificially contrived laboratory experiments bearing little relationship to the outside world. The course comes in the form of fourteen fairly open-ended constructional experiments or projects. Each experiment has associated with it a construction exercise and an explanation. The basic idea behind this dual presentation is that the student can embark on each circuit following only the briefest possible instructions and that an open-ended approach is thereby not prejudiced by an initial lengthy encounter with the theory behind the project; this being a sure way to dampen enthusiasm at the outset. As the investigation progresses, questions inevitably arise. Descriptions of the phenomena encounte...

  11. Basic linear algebra

    CERN Document Server

    Blyth, T S

    2002-01-01

    Basic Linear Algebra is a text for first year students leading from concrete examples to abstract theorems, via tutorial-type exercises. More exercises (of the kind a student may expect in examination papers) are grouped at the end of each section. The book covers the most important basics of any first course on linear algebra, explaining the algebra of matrices with applications to analytic geometry, systems of linear equations, difference equations and complex numbers. Linear equations are treated via Hermite normal forms which provides a successful and concrete explanation of the notion of linear independence. Another important highlight is the connection between linear mappings and matrices leading to the change of basis theorem which opens the door to the notion of similarity. This new and revised edition features additional exercises and coverage of Cramer's rule (omitted from the first edition). However, it is the new, extra chapter on computer assistance that will be of particular interest to readers:...

  12. Basic ergodic theory

    CERN Document Server

    Nadkarni, M G

    2013-01-01

    This is an introductory book on Ergodic Theory. The presentation has a slow pace and the book can be read by any person with a background in basic measure theory and metric topology. A new feature of the book is that the basic topics of Ergodic Theory such as the Poincare recurrence lemma, induced automorphisms and Kakutani towers, compressibility and E. Hopf's theorem, the theorem of Ambrose on representation of flows are treated at the descriptive set-theoretic level before their measure-theoretic or topological versions are presented. In addition, topics around the Glimm-Effros theorem are discussed. In the third edition a chapter entitled 'Additional Topics' has been added. It gives Liouville's Theorem on the existence of invariant measure, entropy theory leading up to Kolmogorov-Sinai Theorem, and the topological dynamics proof of van der Waerden's theorem on arithmetical progressions.

  13. Basic Emotions: A Reconstruction

    Science.gov (United States)

    Mason, William A.; Capitanio, John P.

    2016-01-01

    Emotionality is a basic feature of behavior. The argument over whether the expression of emotions is based primarily on culture (constructivism, nurture) or biology (natural forms, nature) will never be resolved because both alternatives are untenable. The evidence is overwhelming that at all ages and all levels of organization, the development of emotionality is epigenetic: The organism is an active participant in its own development. To ascribe these effects to “experience” was the best that could be done for many years. With the rapid acceleration of information on how changes in organization are actually brought about, it is a good time to review, update, and revitalize our views of experience in relation to the concept of basic emotion. PMID:27110280

  14. Emulsion Science Basic Principles

    CERN Document Server

    Leal-Calderon, Fernando; Schmitt, Véronique

    2007-01-01

    Emulsions are generally made out of two immiscible fluids like oil and water, one being dispersed in the second in the presence of surface-active compounds.They are used as intermediate or end products in a huge range of areas including the food, chemical, cosmetic, pharmaceutical, paint, and coating industries. Besides the broad domain of technological interest, emulsions are raising a variety of fundamental questions at the frontier between physics and chemistry. This book aims to give an overview of the most recent advances in emulsion science. The basic principles, covering aspects of emulsions from their preparation to their destruction, are presented in close relation to both the fundamental physics and the applications of these materials. The book is intended to help scientists and engineers in formulating new materials by giving them the basics of emulsion science.

  15. Basic Semiconductor Physics

    CERN Document Server

    Hamaguchi, Chihiro

    2010-01-01

    This book presents a detailed description of the basic semiconductor physics. The reader is assumed to have a basic command of mathematics and some elementary knowledge of solid state physics. The text covers a wide range of important phenomena in semiconductors, from the simple to the advanced. The reader can understand three different methods of energy band calculations, empirical pseudo-potential, k.p perturbation and tight-binding methods. The effective mass approximation and electron motion in a periodic potential, Boltzmann transport equation and deformation potentials used for full band Monte Carlo simulation are discussed. Experiments and theoretical analysis of cyclotron resonance are discussed in detail because the results are essential to the understanding of semiconductor physics. Optical and transport properties, magneto-transport, two dimensional electron gas transport (HEMT and MOSFET), and quantum transport are reviewed, explaining optical transition, electron phonon interactions, electron mob...

  16. Basic Financial Accounting

    DEFF Research Database (Denmark)

    Wiborg, Karsten

    This textbook on Basic Financial Accounting is targeted students in the economics studies at universities and business colleges having an introductory subject in the external dimension of the company's economic reporting, including bookkeeping, etc. The book includes the following subjects......: business entities, the transformation process, types of businesses, stakeholders, legislation, the annual report, the VAT system, double-entry bookkeeping, inventories, and year-end cast flow analysis....

  17. Basic of Neutron NDA

    Energy Technology Data Exchange (ETDEWEB)

    Trahan, Alexis Chanel [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-09-15

    The objectives of this presentation are to introduce the basic physics of neutron production, interactions and detection; identify the processes that generate neutrons; explain the most common neutron mechanism, spontaneous and induced fission and (a,n) reactions; describe the properties of neutron from different sources; recognize advantages of neutron measurements techniques; recognize common neutrons interactions; explain neutron cross section measurements; describe the fundamental of 3He detector function and designs; and differentiate between passive and active assay techniques.

  18. Basic concepts in oceanography

    International Nuclear Information System (INIS)

    Small, L.F.

    1997-01-01

    Basic concepts in oceanography include major wind patterns that drive ocean currents, and the effects that the earth's rotation, positions of land masses, and temperature and salinity have on oceanic circulation and hence global distribution of radioactivity. Special attention is given to coastal and near-coastal processes such as upwelling, tidal effects, and small-scale processes, as radionuclide distributions are currently most associated with coastal regions. (author)

  19. Basics of Computer Networking

    CERN Document Server

    Robertazzi, Thomas

    2012-01-01

    Springer Brief Basics of Computer Networking provides a non-mathematical introduction to the world of networks. This book covers both technology for wired and wireless networks. Coverage includes transmission media, local area networks, wide area networks, and network security. Written in a very accessible style for the interested layman by the author of a widely used textbook with many years of experience explaining concepts to the beginner.

  20. Risk communication basics

    Energy Technology Data Exchange (ETDEWEB)

    Corrado, P.G. [Lawrence Livermore National Laboratory, CA (United States)

    1995-12-31

    In low-trust, high-concern situations, 50% of your credibility comes from perceived empathy and caring, demonstrated in the first 30 s you come in contact with someone. There is no second chance for a first impression. These and other principles contained in this paper provide you with a basic level of understanding of risk communication. The principles identified are time-tested caveats and will assist you in effectively communicating technical information.

  1. Risk communication basics

    International Nuclear Information System (INIS)

    Corrado, P.G.

    1995-01-01

    In low-trust, high-concern situations, 50% of your credibility comes from perceived empathy and caring, demonstrated in the first 30 s you come in contact with someone. There is no second chance for a first impression. These and other principles contained in this paper provide you with a basic level of understanding of risk communication. The principles identified are time-tested caveats and will assist you in effectively communicating technical information

  2. Basic nucleonics. 2. ed.

    International Nuclear Information System (INIS)

    Guzman, M.E.

    1989-01-01

    This book is oriented mainly towards professionals who are not physicists or experts in nuclear sciences, physicians planning to specialize in nuclear medicine or radiotherapy and technicians involved in nuclear applications. The book covers the fundamental concepts of nuclear science and technology in a simple and ordered fashion. Theory is illustrated with appropriate exercises and answers. With 17 chapters plus 3 appendices on mathematics, basic concepts are covered in: nuclear science, radioactivity, radiation and matter, nuclear reactions, X rays, shielding and radioprotection

  3. Basic Microfluidics Theory

    DEFF Research Database (Denmark)

    Svendsen, Winnie Edith

    2015-01-01

    ,000 m−1, which is a huge difference and has a large impact on flow behavior. In this chapter the basic microfluidic theory will be presented, enabling the reader to gain a comprehensive understanding of how liquids behave at the microscale, enough to be able to engage in design of micro systems...... and to support the theory used in other chapters in the book, but without going into the deep underlying theoretical approach....

  4. Classifying basic research designs.

    Science.gov (United States)

    Burkett, G L

    1990-01-01

    Considerable confusion over terminology for classifying basic types of research design in family medicine stems from the rich variety of substantive topics studied by family medicine researchers, differences in research terminology among the disciplines that family medicine research draws from, and lack of uniform research design terminology within these disciplines themselves. Many research design textbooks themselves fail to specify the dimensions on which research designs are classified or the logic underlying the classification systems proposed. This paper describes a typology based on three dimensions that may be used to characterize the basic design qualities of any study. These dimensions are: 1) the nature of the research objective (exploratory, descriptive, or analytic); 2) the time frame under investigation (retrospective, cross-sectional, or prospective); and 3) whether the investigator intervenes in the events under study (observational or interventional). This three-dimensional typology may be helpful for teaching basic research design concepts, for contemplating research design decisions in planning a study, and as a basis for further consideration of a more detailed, uniform research design classification system.

  5. Catalyst in Basic Oleochemicals

    Directory of Open Access Journals (Sweden)

    Eva Suyenty

    2007-10-01

    Full Text Available Currently Indonesia is the world largest palm oil producer with production volume reaching 16 million tones per annum. The high crude oil and ethylene prices in the last 3 – 4 years contribute to the healthy demand growth for basic oleochemicals: fatty acids and fatty alcohols. Oleochemicals are starting to replace crude oil derived products in various applications. As widely practiced in petrochemical industry, catalyst plays a very important role in the production of basic oleochemicals. Catalytic reactions are abound in the production of oleochemicals: Nickel based catalysts are used in the hydrogenation of unsaturated fatty acids; sodium methylate catalyst in the transesterification of triglycerides; sulfonic based polystyrene resin catalyst in esterification of fatty acids; and copper chromite/copper zinc catalyst in the high pressure hydrogenation of methyl esters or fatty acids to produce fatty alcohols. To maintain long catalyst life, it is crucial to ensure the absence of catalyst poisons and inhibitors in the feed. The preparation methods of nickel and copper chromite catalysts are as follows: precipitation, filtration, drying, and calcinations. Sodium methylate is derived from direct reaction of sodium metal and methanol under inert gas. The sulfonic based polystyrene resin is derived from sulfonation of polystyrene crosslinked with di-vinyl-benzene. © 2007 BCREC UNDIP. All rights reserved.[Presented at Symposium and Congress of MKICS 2007, 18-19 April 2007, Semarang, Indonesia][How to Cite: E. Suyenty, H. Sentosa, M. Agustine, S. Anwar, A. Lie, E. Sutanto. (2007. Catalyst in Basic Oleochemicals. Bulletin of Chemical Reaction Engineering and Catalysis, 2 (2-3: 22-31.  doi:10.9767/bcrec.2.2-3.6.22-31][How to Link/DOI: http://dx.doi.org/10.9767/bcrec.2.2-3.6.22-31 || or local: http://ejournal.undip.ac.id/index.php/bcrec/article/view/6

  6. Electrical installation calculations basic

    CERN Document Server

    Kitcher, Christopher

    2013-01-01

    All the essential calculations required for basic electrical installation workThe Electrical Installation Calculations series has proved an invaluable reference for over forty years, for both apprentices and professional electrical installation engineers alike. The book provides a step-by-step guide to the successful application of electrical installation calculations required in day-to-day electrical engineering practice. A step-by-step guide to everyday calculations used on the job An essential aid to the City & Guilds certificates at Levels 2 and 3Fo

  7. Machine shop basics

    CERN Document Server

    Miller, Rex

    2004-01-01

    Use the right tool the right wayHere, fully updated to include new machines and electronic/digital controls, is the ultimate guide to basic machine shop equipment and how to use it. Whether you're a professional machinist, an apprentice, a trade student, or a handy homeowner, this fully illustrated volume helps you define tools and use them properly and safely. It's packed with review questions for students, and loaded with answers you need on the job.Mark Richard Miller is a Professor and Chairman of the Industrial Technology Department at Texas A&M University in Kingsville, T

  8. Back to basics audio

    CERN Document Server

    Nathan, Julian

    1998-01-01

    Back to Basics Audio is a thorough, yet approachable handbook on audio electronics theory and equipment. The first part of the book discusses electrical and audio principles. Those principles form a basis for understanding the operation of equipment and systems, covered in the second section. Finally, the author addresses planning and installation of a home audio system.Julian Nathan joined the audio service and manufacturing industry in 1954 and moved into motion picture engineering and production in 1960. He installed and operated recording theaters in Sydney, Austra

  9. C# Database Basics

    CERN Document Server

    Schmalz, Michael

    2012-01-01

    Working with data and databases in C# certainly can be daunting if you're coming from VB6, VBA, or Access. With this hands-on guide, you'll shorten the learning curve considerably as you master accessing, adding, updating, and deleting data with C#-basic skills you need if you intend to program with this language. No previous knowledge of C# is necessary. By following the examples in this book, you'll learn how to tackle several database tasks in C#, such as working with SQL Server, building data entry forms, and using data in a web service. The book's code samples will help you get started

  10. Basic heat transfer

    CERN Document Server

    Bacon, D H

    2013-01-01

    Basic Heat Transfer aims to help readers use a computer to solve heat transfer problems and to promote greater understanding by changing data values and observing the effects, which are necessary in design and optimization calculations.The book is concerned with applications including insulation and heating in buildings and pipes, temperature distributions in solids for steady state and transient conditions, the determination of surface heat transfer coefficients for convection in various situations, radiation heat transfer in grey body problems, the use of finned surfaces, and simple heat exc

  11. Basic bladder neurophysiology.

    Science.gov (United States)

    Clemens, J Quentin

    2010-11-01

    Maintenance of normal lower urinary tract function is a complex process that requires coordination between the central nervous system and the autonomic and somatic components of the peripheral nervous system. This article provides an overview of the basic principles that are recognized to regulate normal urine storage and micturition, including bladder biomechanics, relevant neuroanatomy, neural control of lower urinary tract function, and the pharmacologic processes that translate the neural signals into functional results. Finally, the emerging role of the urothelium as a sensory structure is discussed. Copyright © 2010 Elsevier Inc. All rights reserved.

  12. Frequency control modelling - basics

    DEFF Research Database (Denmark)

    Hansen, Anca Daniela; Sørensen, Poul Ejnar; Zeni, Lorenzo

    2016-01-01

    The purpose of this report is to provide an introduction on how the system balance in an island system can be maintained by controlling the frequency. The power balance differential equation, which is fundamental in understanding the effect on the system frequency of the unbalance between...... generation and consumption, is addressed. Basic topics on the main components of a generating unit, such generators, prime movers and governors are presented. A simple dynamic model for an island power system, containing realistic dynamic representations of generators, loads, prime movers, governors...

  13. Basic genetics for dermatologists

    Directory of Open Access Journals (Sweden)

    Muthu Sendhil Kumaran

    2013-01-01

    Full Text Available During the past few decades, advances in the field of molecular genetics have enriched us in understanding the pathogenesis of diseases, their identification, and appropriate therapeutic interventions. In the last 20 years, genetic basis of more than 350 monogenic skin diseases have been elucidated and is counting. The widespread use of molecular genetics as a tool in diagnosis is not practiced routinely due to genetic heterogenicity, limited access and low sensitivity. In this review, we have presented the very basics of genetics so as to enable dermatologists to have working understanding of medical genetics.

  14. Basic structural dynamics

    CERN Document Server

    Anderson, James C

    2012-01-01

    A concise introduction to structural dynamics and earthquake engineering Basic Structural Dynamics serves as a fundamental introduction to the topic of structural dynamics. Covering single and multiple-degree-of-freedom systems while providing an introduction to earthquake engineering, the book keeps the coverage succinct and on topic at a level that is appropriate for undergraduate and graduate students. Through dozens of worked examples based on actual structures, it also introduces readers to MATLAB, a powerful software for solving both simple and complex structural d

  15. Basic research projects

    International Nuclear Information System (INIS)

    1979-04-01

    The research programs under the cognizance of the Office of Energy Research (OER) are directed toward discovery of natural laws and new knowledge, and to improved understanding of the physical and biological sciences as related to the development, use, and control of energy. The ultimate goal is to develop a scientific underlay for the overall DOE effort and the fundamental principles of natural phenomena so that these phenomena may be understood, and new principles, formulated. The DOE-OER outlay activities include three major programs: High Energy Physics, Nuclear Physics, and Basic Energy Sciences. Taken together, these programs represent some 30 percent of the Nation's Federal support of basic research in the energy sciences. The research activities of OER involve more than 6,000 scientists and engineers working in some 17 major Federal Research Centers and at more than 135 different universities and industrial firms throughout the United States. Contract holders in the areas of high-energy physics, nuclear physics, materials sciences, nuclear science, chemical sciences, engineering, mathematics geosciences, advanced energy projects, and biological energy research are listed. Funding trends for recent years are outlined

  16. Basic research projects

    Energy Technology Data Exchange (ETDEWEB)

    1979-04-01

    The research programs under the cognizance of the Office of Energy Research (OER) are directed toward discovery of natural laws and new knowledge, and to improved understanding of the physical and biological sciences as related to the development, use, and control of energy. The ultimate goal is to develop a scientific underlay for the overall DOE effort and the fundamental principles of natural phenomena so that these phenomena may be understood, and new principles, formulated. The DOE-OER outlay activities include three major programs: High Energy Physics, Nuclear Physics, and Basic Energy Sciences. Taken together, these programs represent some 30 percent of the Nation's Federal support of basic research in the energy sciences. The research activities of OER involve more than 6,000 scientists and engineers working in some 17 major Federal Research Centers and at more than 135 different universities and industrial firms throughout the United States. Contract holders in the areas of high-energy physics, nuclear physics, materials sciences, nuclear science, chemical sciences, engineering, mathematics geosciences, advanced energy projects, and biological energy research are listed. Funding trends for recent years are outlined. (RWR)

  17. Basic and clinical immunology

    Science.gov (United States)

    Chinen, Javier; Shearer, William T.

    2003-01-01

    Progress in immunology continues to grow exponentially every year. New applications of this knowledge are being developed for a broad range of clinical conditions. Conversely, the study of primary and secondary immunodeficiencies is helping to elucidate the intricate mechanisms of the immune system. We have selected a few of the most significant contributions to the fields of basic and clinical immunology published between October 2001 and October 2002. Our choice of topics in basic immunology included the description of T-bet as a determinant factor for T(H)1 differentiation, the role of the activation-induced cytosine deaminase gene in B-cell development, the characterization of CD4(+)CD25(+) regulatory T cells, and the use of dynamic imaging to study MHC class II transport and T-cell and dendritic cell membrane interactions. Articles related to clinical immunology that were selected for review include the description of immunodeficiency caused by caspase 8 deficiency; a case series report on X-linked agammaglobulinemia; the mechanism of action, efficacy, and complications of intravenous immunoglobulin; mechanisms of autoimmunity diseases; and advances in HIV pathogenesis and vaccine development. We also reviewed two articles that explore the possible alterations of the immune system caused by spaceflights, a new field with increasing importance as human space expeditions become a reality in the 21st century.

  18. Basic scattering theory

    International Nuclear Information System (INIS)

    Queen, N.M.

    1978-01-01

    This series of lectures on basic scattering theory were given as part of a course for postgraduate high energy physicists and were designed to acquaint the student with some of the basic language and formalism used for the phenomenological description of nuclear reactions and decay processes used for the study of elementary particle interactions. Well established and model independent aspects of scattering theory, which are the basis of S-matrix theory, are considered. The subject is considered under the following headings; the S-matrix, cross sections and decay rates, phase space, relativistic kinematics, the Mandelstam variables, the flux factor, two-body phase space, Dalitz plots, other kinematic plots, two-particle reactions, unitarity, the partial-wave expansion, resonances (single-channel case), multi-channel resonances, analyticity and crossing, dispersion relations, the one-particle exchange model, the density matrix, mathematical properties of the density matrix, the density matrix in scattering processes, the density matrix in decay processes, and the helicity formalism. Some exercises for the students are included. (U.K.)

  19. Transportation Emissions: some basics

    DEFF Research Database (Denmark)

    Kontovas, Christos A.; Psaraftis, Harilaos N.

    2016-01-01

    Transportation is the backbone of international trade and a key engine driving globalization. However, there is growing concern that the Earth’s atmospheric composition is being altered by human activities, including transportation, which can lead to climate change. Air pollution from transportat...... of the energy efficiency gap and examines why governments and companies may forego cost-effective investments in energy efficiency, even though they could significantly reduce energy consumption at a lower cost....... transportation and especially carbon dioxide emissions are at the center stage of discussion by the world community through various international treaties, such as the Kyoto Protocol. The transportation sector also emits non-CO2 pollutants that have important effects on air quality, climate, and public health....... The main purpose of this chapter is to introduce some basic concepts that are relevant in the quest of green transportation logistics. First, we present the basics of estimating emissions from transportation activities, the current statistics and future trends, as well as the total impact of air emissions...

  20. Basic research on maxillofacial implants

    Energy Technology Data Exchange (ETDEWEB)

    Matsui, Yoshiro [Showa Univ., Tokyo (Japan). School of Dentistry

    2001-11-01

    Osseointegrated implants have begun to be used not only in general practice in dentistry but also in various clinical situations in the maxillofacial region. The process has yielded three problems: the spread of application, new materials and diagnostic methods, and management for difficult situations. This paper presents basic data and clinical guidelines for new applications, it investigates the characteristics of the materials and the usefulness of a new diagnostic method, and it studies effective techniques for difficult cases. The results obtained are as follows: Investigations into the spreading application. The lateral and superior orbital rim have sufficient bone thickness and width for the implant body to be placed. Osseointegrated implants, especially by the fixed bridge technique, are not recommended in the craniofacial bone and jaws of young children. Implant placement into bone after/before irradiation must be performed in consideration of impaired osteogenesis, the decrease of trabecular bone, and the time interval between implantation and irradiation. Investigations into materials and diagnostic methods. Hydroxyapatite-coated and titanium implants should be selected according to the characteristics of the materials. A dental simulating soft may also be applicable in the craniofacial region. Investigations into the management of difficult cases. Hyperbaric oxygen therapy (HBO), bone morphogenetic protein (BMP), and tissue engineering should be useful for improving the quality and increasing the quantity of bone where implants are placed. Soft tissue around implants placed in the reconstructed area should be replaced with mucosal tissue. The data obtained here should be useful for increasing the efficiency of osseointegrated implants, but further basic research is required in the future. (author)

  1. Basic research on maxillofacial implants

    International Nuclear Information System (INIS)

    Matsui, Yoshiro

    2001-01-01

    Osseointegrated implants have begun to be used not only in general practice in dentistry but also in various clinical situations in the maxillofacial region. The process has yielded three problems: the spread of application, new materials and diagnostic methods, and management for difficult situations. This paper presents basic data and clinical guidelines for new applications, it investigates the characteristics of the materials and the usefulness of a new diagnostic method, and it studies effective techniques for difficult cases. The results obtained are as follows: Investigations into the spreading application. The lateral and superior orbital rim have sufficient bone thickness and width for the implant body to be placed. Osseointegrated implants, especially by the fixed bridge technique, are not recommended in the craniofacial bone and jaws of young children. Implant placement into bone after/before irradiation must be performed in consideration of impaired osteogenesis, the decrease of trabecular bone, and the time interval between implantation and irradiation. Investigations into materials and diagnostic methods. Hydroxyapatite-coated and titanium implants should be selected according to the characteristics of the materials. A dental simulating soft may also be applicable in the craniofacial region. Investigations into the management of difficult cases. Hyperbaric oxygen therapy (HBO), bone morphogenetic protein (BMP), and tissue engineering should be useful for improving the quality and increasing the quantity of bone where implants are placed. Soft tissue around implants placed in the reconstructed area should be replaced with mucosal tissue. The data obtained here should be useful for increasing the efficiency of osseointegrated implants, but further basic research is required in the future. (author)

  2. Chernobyl versus Basic Law?

    International Nuclear Information System (INIS)

    Sauer, G.W.

    1986-01-01

    The author discusses the terms 'remaining risk to be accepted' and 'remainder of the aggregate risk', and explains the line of action to be adopted in compliance with the Constitution in order to respond to the event at Chernobyl: The Constitution demands maximum acceptable limits to be defined as low as possible. The author discusses the various dose estimations and the contradictions to be observed in this context. He states that the Chernobyl accident has done most harm to our legal system, as the basic right of freedom from injury has been ploughed under with the radioactivity that covered the soil after the Chernobyl accident. But, he says, a positive effect is that the idea of abandoning nuclear power as too dangerous a technology has gained more widespread acceptance. (HSCH) [de

  3. Basics of plasma astrophysics

    CERN Document Server

    Chiuderi, Claudio

    2015-01-01

    This book is an introduction to contemporary plasma physics that discusses the most relevant recent advances in the field and covers a careful choice of applications to various branches of astrophysics and space science. The purpose of the book is to allow the student to master the basic concepts of plasma physics and to bring him or her up to date in a number of relevant areas of current research. Topics covered include orbit theory, kinetic theory, fluid models, magnetohydrodynamics, MHD turbulence, instabilities, discontinuities, and magnetic reconnection. Some prior knowledge of classical physics is required, in particular fluid mechanics, statistical physics, and electrodynamics. The mathematical developments are self-contained and explicitly detailed in the text. A number of exercises are provided at the end of each chapter, together with suggestions and solutions.

  4. Atomic Basic Blocks

    Science.gov (United States)

    Scheler, Fabian; Mitzlaff, Martin; Schröder-Preikschat, Wolfgang

    Die Entscheidung, einen zeit- bzw. ereignisgesteuerten Ansatz für ein Echtzeitsystem zu verwenden, ist schwierig und sehr weitreichend. Weitreichend vor allem deshalb, weil diese beiden Ansätze mit äußerst unterschiedlichen Kontrollflussabstraktionen verknüpft sind, die eine spätere Migration zum anderen Paradigma sehr schwer oder gar unmöglich machen. Wir schlagen daher die Verwendung einer Zwischendarstellung vor, die unabhängig von der jeweils verwendeten Kontrollflussabstraktion ist. Für diesen Zweck verwenden wir auf Basisblöcken basierende Atomic Basic Blocks (ABB) und bauen darauf ein Werkzeug, den Real-Time Systems Compiler (RTSC) auf, der die Migration zwischen zeit- und ereignisgesteuerten Systemen unterstützt.

  5. Basic engineering mathematics

    CERN Document Server

    Bird, John

    2014-01-01

    Introductory mathematics written specifically for students new to engineering Now in its sixth edition, Basic Engineering Mathematics is an established textbook that has helped thousands of students to succeed in their exams. John Bird's approach is based on worked examples and interactive problems. This makes it ideal for students from a wide range of academic backgrounds as the student can work through the material at their own pace. Mathematical theories are explained in a straightforward manner, being supported by practical engineering examples and applications in order to ensure that readers can relate theory to practice. The extensive and thorough topic coverage makes this an ideal text for introductory level engineering courses. This title is supported by a companion website with resources for both students and lecturers, including lists of essential formulae, multiple choice tests, full solutions for all 1,600 further questions contained within the practice exercises, and biographical information on t...

  6. Basic semiconductor physics

    CERN Document Server

    Hamaguchi, Chihiro

    2017-01-01

    This book presents a detailed description of basic semiconductor physics. The text covers a wide range of important phenomena in semiconductors, from the simple to the advanced. Four different methods of energy band calculations in the full band region are explained: local empirical pseudopotential, non-local pseudopotential, KP perturbation and tight-binding methods. The effective mass approximation and electron motion in a periodic potential, Boltzmann transport equation and deformation potentials used for analysis of transport properties are discussed. Further, the book examines experiments and theoretical analyses of cyclotron resonance in detail. Optical and transport properties, magneto-transport, two-dimensional electron gas transport (HEMT and MOSFET) and quantum transport are reviewed, while optical transition, electron-phonon interaction and electron mobility are also addressed. Energy and electronic structure of a quantum dot (artificial atom) are explained with the help of Slater determinants. The...

  7. Magnetism basics and applications

    CERN Document Server

    Stefanita, Carmen-Gabriela

    2012-01-01

    This textbook is aimed at engineering students who are likely to come across magnetics applications in their professional practice. Whether designing lithography equipment containing ferromagnetic brushes, or detecting defects in aeronautics, some basic knowledge of 21st century magnetism is needed. From the magnetic tape on the pocket credit card to the read head in a personal computer, people run into magnetism in many products. Furthermore, in a variety of disciplines tools of the trade exploit magnetic principles, and many interdisciplinary laboratory research areas cross paths with magnetic phenomena that may seem mysterious to the untrained mind. Therefore, this course offers a broad coverage of magnetism topics encountered more often in this millenium, revealing key concepts on which many practical applications rest. Some traditional subjects in magnetism are discussed in the first half of the book, followed by areas likely to spark the curiosity of those more interested in today’s technological achi...

  8. Basic real analysis

    CERN Document Server

    Sohrab, Houshang H

    2014-01-01

    This expanded second edition presents the fundamentals and touchstone results of real analysis in full rigor, but in a style that requires little prior familiarity with proofs or mathematical language. The text is a comprehensive and largely self-contained introduction to the theory of real-valued functions of a real variable. The chapters on Lebesgue measure and integral have been rewritten entirely and greatly improved. They now contain Lebesgue’s differentiation theorem as well as his versions of the Fundamental Theorem(s) of Calculus. With expanded chapters, additional problems, and an expansive solutions manual, Basic Real Analysis, Second Edition, is ideal for senior undergraduates and first-year graduate students, both as a classroom text and a self-study guide. Reviews of first edition: The book is a clear and well-structured introduction to real analysis aimed at senior undergraduate and beginning graduate students. The prerequisites are few, but a certain mathematical sophistication is required. ....

  9. 15. Basic economic indicators

    International Nuclear Information System (INIS)

    Carless, J.; Dow, B.; Farivari, R.; O'Connor, J.; Fox, T.; Tunstall, D.; Mentzingen, M.

    1992-01-01

    The clear value of economic data and analysis to decisionmakers has motivated them to mandate the creation of extensive global economic data sets. This chapter contains a set of these basic economic data, which provides the context for understanding the causes and the consequences of many of the decisions that affect the world's resources. Many traditional economic indicators fail to account for the depletion or deterioration of natural resources, the long-term consequences of such depletion, the equitable distribution of income within a country, or the sustainability of current economic practices. The type of measurement shown here, however, is still useful in showing the great differences between the wealthiest and the poorest countries. Tables are given on the following: Gross national product and official development assistance 1969-89; External debt indicators 1979-89; Central government expenditures; and World commodity indexes and prices 1975-89

  10. Cloud computing basics

    CERN Document Server

    Srinivasan, S

    2014-01-01

    Cloud Computing Basics covers the main aspects of this fast moving technology so that both practitioners and students will be able to understand cloud computing. The author highlights the key aspects of this technology that a potential user might want to investigate before deciding to adopt this service. This book explains how cloud services can be used to augment existing services such as storage, backup and recovery. Addressing the details on how cloud security works and what the users must be prepared for when they move their data to the cloud. Also this book discusses how businesses could prepare for compliance with the laws as well as industry standards such as the Payment Card Industry.

  11. Track A Basic Science

    OpenAIRE

    Sargeant, D.; Deverasetty, S.; Luo, Y.; Villahoz-Baleta, A.; Zobrist, S.; Rathnayake, V.; Russo, J.; Muesing, M.; Schiller, M.; Andrabi, R.; Kumar, R.; Bala, M.; Nair, A.; Biswas, A.; Wig, N.

    2012-01-01

    Background Many HIV databases and applications focus on a limited domain of HIV knowledge. Since even a “simple” organism like HIV represents a very complex system with many interacting elements, the fractured structure of existing databases and applications likely limits our ability to investigate and understand HIV. To facilitate research, therefore, we have built HIVToolbox, which integrates much of the knowledge about HIV proteins and presents the data in an interactive web application. H...

  12. Basic cell culture.

    Science.gov (United States)

    Pollard, J W

    1990-01-01

    This article will describe the basic techniques required for successful cell culture. It will also act to introduce some of the other chapters in this volume. It is not intended, as this volume is not, to describe the establishment of a tissue culture laboratory, nor to provide a historical or theoretical survey of cell culture. There are several books that adequately cover these areas, including the now somewhat dated but still valuable volume by Paul (1), the multi-authored Methods in Enzymology volume edited by Jakoby and Pastan (2), and the new edition of Freshney (3). Instead, this chapter's focus will be on the techniques for establishing primary rodent cell cultures from embryos and adult skin, maintaining and subculturing these fibro-blasts and their transformed derivatives, and the isolation of genetically pure strains. The cells described are all derived from Chinese hamsters since, to date, these cells, have proved to be the most useful for somatic cell genetics (4,5). The techniques, however, are generally applicable to most fibroblastic cell types.

  13. Basics of aerothermodynamics

    CERN Document Server

    Hirschel, Ernst Heinrich

    2015-01-01

    This successful book gives an introduction to the basics of aerothermodynamics, as applied in particular to winged re-entry vehicles and airbreathing hypersonic cruise and acceleration vehicles. The book gives a review of the issues of transport of momentum, energy and mass, real-gas effects as well as inviscid and viscous flow phenomena. In this second, revised edition the chapters with the classical topics of aerothermodynamics more or less were left untouched. The access to some single topics of practical interest was improved. Auxiliary chapters were put into an appendix. The recent successful flights of the X-43A and the X-51A indicate that the dawn of sustained airbreathing hypersonic flight now has arrived. This proves that the original approach of the book to put emphasis on viscous effects and the aerothermodynamics of radiation-cooled vehicle surfaces was timely. This second, revised edition even more accentuates these topics. A new, additional chapter treats examples of viscous thermal surface eff...

  14. Basic operator theory

    CERN Document Server

    Gohberg, Israel

    2001-01-01

    rii application of linear operators on a Hilbert space. We begin with a chapter on the geometry of Hilbert space and then proceed to the spectral theory of compact self adjoint operators; operational calculus is next presented as a nat­ ural outgrowth of the spectral theory. The second part of the text concentrates on Banach spaces and linear operators acting on these spaces. It includes, for example, the three 'basic principles of linear analysis and the Riesz­ Fredholm theory of compact operators. Both parts contain plenty of applications. All chapters deal exclusively with linear problems, except for the last chapter which is an introduction to the theory of nonlinear operators. In addition to the standard topics in functional anal­ ysis, we have presented relatively recent results which appear, for example, in Chapter VII. In general, in writ­ ing this book, the authors were strongly influenced by re­ cent developments in operator theory which affected the choice of topics, proofs and exercises. One ...

  15. Basic concepts of epidemiology

    International Nuclear Information System (INIS)

    Savitz, D.A.

    1984-01-01

    Epidemiology can be defined simply as the science of the distribution and determinants of disease in human populations. As a descriptive tool, epidemiology can aid health care service providers, for example, in allocation of resources. In its analytic capacity, the epidemiologic approach can help identify determinants of disease through the study of human populations. Epidemiology is primarily an observational rather than experimental methodology, with corresponding strengths and limitations. Relative to other approaches for assessing disease etiology and impacts of potential health hazards, epidemiology has a rather unique role that is complementary to, but independent of, both basic biologic sciences and clinical medicine. Experimental biologic sciences such as toxicology and physiology provide critical information on biologic mechanisms of disease required for causal inference. Clinical medicine often serves as the warning system that provides etiologic clues to be pursued through systematic investigation. The advantage of the epidemiologic approach is its reliance on human field experience, that is, the real world. While laboratory experimentation is uniquely well suited to defining potential hazards, it can neither determine whether human populations have actually been affected nor quantify that effect. Building all the complexities of human behavior and external factors into a laboratory study or mathematical model is impossible. By studying the world as it exists, epidemiology examines the integrated, summarized product of the myriad factors influencing health

  16. Nanodesign: some basic questions

    CERN Document Server

    Schommers, Wolfram

    2013-01-01

    There is no doubt that nanoscience will be the dominant direction for technology in this century, and that this science will influence our lives to a large extent as well as open completely new perspectives on all scientific and technological disciplines. To be able to produce optimal nanosystems with tailor-made properties, it is necessary to analyze and construct such systems in advance by adequate theoretical and computational methods. Since we work in nanoscience and nanotechnology at the ultimate level, we have to apply the basic laws of physics. What methods and tools are relevant here? The book gives an answer to this question. The background of the theoretical methods and tools is critically discussed, and also the world view on which these physical laws are based. Such a debate is not only of academic interest but is of highly general concern, and this is because we constantly move in nanoscience and nanotechnology between two extreme poles, between infinite life and total destruction . On the one ...

  17. Basic Data on Biogas

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-07-01

    Renewable gases such as biogas and biomethane are considered as key energy carrier when the society is replacing fossil fuels with renewable alternatives. In Sweden, almost 80 % of the fossil fuels are used in the transport sector. Therefore, the focus in Sweden has been to use the produced biogas in this sector as vehicle gas. Basic Data on Biogas contains an overview of production, utilisation, climate effects etc. of biogas from a Swedish perspective. The purpose is to give an easy overview of the current situation in Sweden for politicians, decision makers and interested public. 1.4 TWh of biogas is produced annually in Sweden at approximately 230 facilities. The 135 wastewater treatment plants that produce biogas contribute with around half of the production. In order to reduce the sludge volume, biogas has been produced at wastewater treatment plants for decades. New biogas plants are mainly co-digestion plants and farm plants. The land filling of organic waste has been banned since 2005, thus the biogas produced in landfills is decreasing.

  18. Visual Basic 2012 programmer's reference

    CERN Document Server

    Stephens, Rod

    2012-01-01

    The comprehensive guide to Visual Basic 2012 Microsoft Visual Basic (VB) is the most popular programming language in the world, with millions of lines of code used in businesses and applications of all types and sizes. In this edition of the bestselling Wrox guide, Visual Basic expert Rod Stephens offers novice and experienced developers a comprehensive tutorial and reference to Visual Basic 2012. This latest edition introduces major changes to the Visual Studio development platform, including support for developing mobile applications that can take advantage of the Windows 8 operating system

  19. Basic tastes and basic emotions: Basic problems and perspectives for a nonbasic solution

    OpenAIRE

    Sander, David

    2017-01-01

    Contemporary behavioral and brain scientists consider the existence of so-called basic emotions in a similar way to the one described by Erickson for so-called basic tastes. Commenting on this analogy, I argue that similar basic problems are encountered in both perspectives, and I suggest a potential nonbasic solution that is tested in emotion research (i.e., the appraisal model of emotion)

  20. Basic Blood Tests (For Parents)

    Science.gov (United States)

    ... Safe Videos for Educators Search English Español Basic Blood Chemistry Tests KidsHealth / For Parents / Basic Blood Chemistry Tests Print ... learn how the body’s organs are working. Often, blood tests check electrolytes, the minerals that help keep the ...