Metagenome and Metatranscriptome Analyses Using Protein Family Profiles.

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Cuncong Zhong

2016-07-01

Full Text Available Analyses of metagenome data (MG and metatranscriptome data (MT are often challenged by a paucity of complete reference genome sequences and the uneven/low sequencing depth of the constituent organisms in the microbial community, which respectively limit the power of reference-based alignment and de novo sequence assembly. These limitations make accurate protein family classification and abundance estimation challenging, which in turn hamper downstream analyses such as abundance profiling of metabolic pathways, identification of differentially encoded/expressed genes, and de novo reconstruction of complete gene and protein sequences from the protein family of interest. The profile hidden Markov model (HMM framework enables the construction of very useful probabilistic models for protein families that allow for accurate modeling of position specific matches, insertions, and deletions. We present a novel homology detection algorithm that integrates banded Viterbi algorithm for profile HMM parsing with an iterative simultaneous alignment and assembly computational framework. The algorithm searches a given profile HMM of a protein family against a database of fragmentary MG/MT sequencing data and simultaneously assembles complete or near-complete gene and protein sequences of the protein family. The resulting program, HMM-GRASPx, demonstrates superior performance in aligning and assembling homologs when benchmarked on both simulated marine MG and real human saliva MG datasets. On real supragingival plaque and stool MG datasets that were generated from healthy individuals, HMM-GRASPx accurately estimates the abundances of the antimicrobial resistance (AMR gene families and enables accurate characterization of the resistome profiles of these microbial communities. For real human oral microbiome MT datasets, using the HMM-GRASPx estimated transcript abundances significantly improves detection of differentially expressed (DE genes. Finally, HMM

A guild of 45 CRISPR-associated (Cas protein families and multiple CRISPR/Cas subtypes exist in prokaryotic genomes.

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Daniel H Haft

2005-11-01

Full Text Available Clustered regularly interspaced short palindromic repeats (CRISPRs are a family of DNA direct repeats found in many prokaryotic genomes. Repeats of 21-37 bp typically show weak dyad symmetry and are separated by regularly sized, nonrepetitive spacer sequences. Four CRISPR-associated (Cas protein families, designated Cas1 to Cas4, are strictly associated with CRISPR elements and always occur near a repeat cluster. Some spacers originate from mobile genetic elements and are thought to confer "immunity" against the elements that harbor these sequences. In the present study, we have systematically investigated uncharacterized proteins encoded in the vicinity of these CRISPRs and found many additional protein families that are strictly associated with CRISPR loci across multiple prokaryotic species. Multiple sequence alignments and hidden Markov models have been built for 45 Cas protein families. These models identify family members with high sensitivity and selectivity and classify key regulators of development, DevR and DevS, in Myxococcus xanthus as Cas proteins. These identifications show that CRISPR/cas gene regions can be quite large, with up to 20 different, tandem-arranged cas genes next to a repeat cluster or filling the region between two repeat clusters. Distinctive subsets of the collection of Cas proteins recur in phylogenetically distant species and correlate with characteristic repeat periodicity. The analyses presented here support initial proposals of mobility of these units, along with the likelihood that loci of different subtypes interact with one another as well as with host cell defensive, replicative, and regulatory systems. It is evident from this analysis that CRISPR/cas loci are larger, more complex, and more heterogeneous than previously appreciated.

Insight into Two ABC Transporter Families Involved in Lantibiotic Resistance

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Rebecca Clemens

2018-01-01

Full Text Available Antimicrobial peptides, which contain (methyl-lanthionine-rings are called lantibiotics. They are produced by several Gram-positive bacteria and are mainly active against these bacteria. Although these are highly potent antimicrobials, some human pathogenic bacteria express specific ABC transporters that confer resistance and counteract their antimicrobial activity. Two distinct ABC transporter families are known to be involved in this process. These are the Cpr- and Bce-type ABC transporter families, named after their involvement in cationic peptide resistance in Clostridium difficile, and bacitracin efflux in Bacillus subtilis, respectively. Both resistance systems differentiate to each other in terms of the proteins involved. Here, we summarize the current knowledge and describe the divergence as well as the common features present in both the systems to confer lantibiotic resistance.

Monoubiquitination of Tob/BTG family proteins competes with degradation-targeting polyubiquitination

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Suzuki, Toru, E-mail: toru@ims.u-tokyo.ac.jp [Division of Oncology, Institute of Medical Science, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639 (Japan); Kim, Minsoo [Division of Bacterial Infection, Institute of Medical Science, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639 (Japan); Kozuka-Hata, Hiroko [Medical Proteomics Laboratory, Institute of Medical Science, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639 (Japan); Watanabe, Masato [Department of Medical Genome Science, School of Frontier Sciences, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa 277-8562 (Japan); Oyama, Masaaki [Medical Proteomics Laboratory, Institute of Medical Science, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639 (Japan); Tsumoto, Kouhei [Medical Proteomics Laboratory, Institute of Medical Science, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639 (Japan); Department of Medical Genome Science, School of Frontier Sciences, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa 277-8562 (Japan); Yamamoto, Tadashi, E-mail: tyamamot@ims.u-tokyo.ac.jp [Division of Oncology, Institute of Medical Science, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639 (Japan); Cell Signal Unit, Okinawa Institute of Science and Technology, 1919-1 Onna-son, Kunigami, Okinawa 904-0412 (Japan)

2011-05-27

Highlights: {yields} Tob/BTG family proteins are monoubiquitinated in the absence of E3s in vitro. {yields} Monoubiquitination sites of Tob are identified by mass spectrometry. {yields} The monoubiquitination event correlates with lower levels of polyubiquitination. -- Abstract: Tob belongs to the anti-proliferative Tob/BTG protein family. The expression level of Tob family proteins is strictly regulated both transcriptionally and through post-translational modification. Ubiquitin (Ub)/proteosome-dependent degradation of Tob family proteins is critical in controlling cell cycle progression and DNA damage responses. Various Ub ligases (E3s) are responsible for degradation of Tob protein. Here, we show that Tob family proteins undergo monoubiquitination even in the absence of E3s in vitro. Determination of the ubiquitination site(s) in Tob by mass spectrometric analysis revealed that two lysine residues (Lys48 and Lys63) located in Tob/BTG homology domain are ubiquitinated. A mutant Tob, in which both Lys48 and Lys63 are substituted with alanine, is more strongly polyubiquitinated than wild-type Tob in vivo. These data suggest that monoubiquitination of Tob family proteins confers resistance against polyubiquitination, which targets proteins for degradation. The strategy for regulating the stability of Tob family proteins suggests a novel role for monoubiquitination.

Monoubiquitination of Tob/BTG family proteins competes with degradation-targeting polyubiquitination

International Nuclear Information System (INIS)

Suzuki, Toru; Kim, Minsoo; Kozuka-Hata, Hiroko; Watanabe, Masato; Oyama, Masaaki; Tsumoto, Kouhei; Yamamoto, Tadashi

2011-01-01

Highlights: → Tob/BTG family proteins are monoubiquitinated in the absence of E3s in vitro. → Monoubiquitination sites of Tob are identified by mass spectrometry. → The monoubiquitination event correlates with lower levels of polyubiquitination. -- Abstract: Tob belongs to the anti-proliferative Tob/BTG protein family. The expression level of Tob family proteins is strictly regulated both transcriptionally and through post-translational modification. Ubiquitin (Ub)/proteosome-dependent degradation of Tob family proteins is critical in controlling cell cycle progression and DNA damage responses. Various Ub ligases (E3s) are responsible for degradation of Tob protein. Here, we show that Tob family proteins undergo monoubiquitination even in the absence of E3s in vitro. Determination of the ubiquitination site(s) in Tob by mass spectrometric analysis revealed that two lysine residues (Lys48 and Lys63) located in Tob/BTG homology domain are ubiquitinated. A mutant Tob, in which both Lys48 and Lys63 are substituted with alanine, is more strongly polyubiquitinated than wild-type Tob in vivo. These data suggest that monoubiquitination of Tob family proteins confers resistance against polyubiquitination, which targets proteins for degradation. The strategy for regulating the stability of Tob family proteins suggests a novel role for monoubiquitination.

Multidrug resistance-associated protein-1 (MRP1 genetic variants, MRP1 protein levels and severity of COPD

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Rutgers Bea

2010-05-01

Full Text Available Abstract Background Multidrug resistance-associated protein-1 (MRP1 protects against oxidative stress and toxic compounds generated by cigarette smoking, which is the main risk factor for chronic obstructive pulmonary disease (COPD. We have previously shown that single nucleotide polymorphisms (SNPs in MRP1 significantly associate with level of FEV1 in two independent population based cohorts. The aim of our study was to assess the associations of MRP1 SNPs with FEV1 level, MRP1 protein levels and inflammatory markers in bronchial biopsies and sputum of COPD patients. Methods Five SNPs (rs212093, rs4148382, rs504348, rs4781699, rs35621 in MRP1 were genotyped in 110 COPD patients. The effects of MRP1 SNPs were analyzed using linear regression models. Results One SNP, rs212093 was significantly associated with a higher FEV1 level and less airway wall inflammation. Another SNP, rs4148382 was significantly associated with a lower FEV1 level, higher number of inflammatory cells in induced sputum and with a higher MRP1 protein level in bronchial biopsies. Conclusions This is the first study linking MRP1 SNPs with lung function and inflammatory markers in COPD patients, suggesting a role of MRP1 SNPs in the severity of COPD in addition to their association with MRP1 protein level in bronchial biopsies.

Rhodnius prolixus supergene families of enzymes potentially associated with insecticide resistance.

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Schama, Renata; Pedrini, Nicolás; Juárez, M Patricia; Nelson, David R; Torres, André Q; Valle, Denise; Mesquita, Rafael D

2016-02-01

Chagas disease or American trypanosomiasis, is a potentially life-threatening illness caused by the protozoan parasite, Trypanosoma cruzi. Once known as an endemic health problem of poor rural populations in Latin American countries, it has now spread worldwide. The parasite is transmitted by triatomine bugs, of which Rhodnius prolixus (Hemiptera, Reduviidae, Triatominae) is one of the vectors and a model organism. This species occurs mainly in Central and South American countries where the disease is endemic. Disease prevention focuses on vector control programs that, in general, rely intensely on insecticide use. However, the massive use of chemical insecticides can lead to resistance. One of the major mechanisms is known as metabolic resistance that is associated with an increase in the expression or activity of detoxification genes. Three of the enzyme families that are involved in this process - carboxylesterases (CCE), glutathione s-transferases (GST) and cytochrome P450s (CYP) - are analyzed in the R. prolixus genome. A similar set of detoxification genes to those of the Hemipteran Acyrthosiphon pisum but smaller than in most dipteran species was found in R. prolixus genome. All major CCE classes (43 genes found) are present but the pheromone/hormone processing class had fewer genes than usual. One main expansion was detected on the detoxification/dietary class. The phosphotriesterase family, recently associated with insecticide resistance, was also represented with one gene. One microsomal GST gene was found and the cytosolic GST gene count (14 genes) is extremely low when compared to the other hemipteran species with sequenced genomes. However, this is similar to Apis mellifera, a species known for its deficit in detoxification genes. In R. prolixus 88 CYP genes were found, with representatives in the four clans (CYP2, CYP3, CYP4 and mitochondrial) usually found in insects. R. prolixus seems to have smaller species-specific expansions of CYP genes than

The human protein disulfide isomerase gene family

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Galligan James J

2012-07-01

Full Text Available Abstract Enzyme-mediated disulfide bond formation is a highly conserved process affecting over one-third of all eukaryotic proteins. The enzymes primarily responsible for facilitating thiol-disulfide exchange are members of an expanding family of proteins known as protein disulfide isomerases (PDIs. These proteins are part of a larger superfamily of proteins known as the thioredoxin protein family (TRX. As members of the PDI family of proteins, all proteins contain a TRX-like structural domain and are predominantly expressed in the endoplasmic reticulum. Subcellular localization and the presence of a TRX domain, however, comprise the short list of distinguishing features required for gene family classification. To date, the PDI gene family contains 21 members, varying in domain composition, molecular weight, tissue expression, and cellular processing. Given their vital role in protein-folding, loss of PDI activity has been associated with the pathogenesis of numerous disease states, most commonly related to the unfolded protein response (UPR. Over the past decade, UPR has become a very attractive therapeutic target for multiple pathologies including Alzheimer disease, Parkinson disease, alcoholic and non-alcoholic liver disease, and type-2 diabetes. Understanding the mechanisms of protein-folding, specifically thiol-disulfide exchange, may lead to development of a novel class of therapeutics that would help alleviate a wide range of diseases by targeting the UPR.

The role of the acidity of N-heteroaryl sulfonamides as inhibitors of bcl-2 family protein-protein interactions.

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Touré, B Barry; Miller-Moslin, Karen; Yusuff, Naeem; Perez, Lawrence; Doré, Michael; Joud, Carol; Michael, Walter; DiPietro, Lucian; van der Plas, Simon; McEwan, Michael; Lenoir, Francois; Hoe, Madelene; Karki, Rajesh; Springer, Clayton; Sullivan, John; Levine, Kymberly; Fiorilla, Catherine; Xie, Xiaoling; Kulathila, Raviraj; Herlihy, Kara; Porter, Dale; Visser, Michael

2013-02-14

Overexpression of the antiapoptotic members of the Bcl-2 family of proteins is commonly associated with cancer cell survival and resistance to chemotherapeutics. Here, we describe the structure-based optimization of a series of N-heteroaryl sulfonamides that demonstrate potent mechanism-based cell death. The role of the acidic nature of the sulfonamide moiety as it relates to potency, solubility, and clearance is examined. This has led to the discovery of novel heterocyclic replacements for the acylsulfonamide core of ABT-737 and ABT-263.

Identification of MarvelD3 as a tight junction-associated transmembrane protein of the occludin family

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Balda Maria S

2009-12-01

Full Text Available Abstract Background Tight junctions are an intercellular adhesion complex of epithelial and endothelial cells, and form a paracellular barrier that restricts the diffusion of solutes on the basis of size and charge. Tight junctions are formed by multiprotein complexes containing cytosolic and transmembrane proteins. How these components work together to form functional tight junctions is still not well understood and will require a complete understanding of the molecular composition of the junction. Results Here we identify a new transmembrane component of tight junctions: MarvelD3, a four-span transmembrane protein. Its predicted transmembrane helices form a Marvel (MAL and related proteins for vesicle traffic and membrane link domain, a structural motif originally discovered in proteins involved in membrane apposition and fusion events, such as the tight junction proteins occludin and tricellulin. In mammals, MarvelD3 is expressed as two alternatively spliced isoforms. Both isoforms exhibit a broad tissue distribution and are expressed by different types of epithelial as well as endothelial cells. MarvelD3 co-localises with occludin at tight junctions in intestinal and corneal epithelial cells. RNA interference experiments in Caco-2 cells indicate that normal MarvelD3 expression is not required for the formation of functional tight junctions but depletion results in monolayers with increased transepithelial electrical resistance. Conclusions Our data indicate that MarvelD3 is a third member of the tight junction-associated occludin family of transmembrane proteins. Similar to occludin, normal expression of MarvelD3 is not essential for the formation of functional tight junctions. However, MarvelD3 functions as a determinant of epithelial paracellular permeability properties.

Expression of multidrug resistance proteins in retinoblastoma

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Swati Shukla

2017-11-01

Full Text Available AIM: To elucidate the mechanism of multidrug resistance in retinoblastoma, and to acquire more insights into in vivo drug resistance. METHODS: Three anticancer drug resistant Y79 human RB cells were generated against vincristine, etoposide or carboplatin, which are used for conventional chemotherapy in RB. Primary cultures from enucleated eyes after chemotherapy (PCNC were also prepared. Their chemosensitivity to chemotherapeutic agents (vincristine, etoposide and carboplatin were measured using MTT assay. Western blot analysis was performed to evaluate the expression of p53, Bcl-2 and various multidrug resistant proteins in retinoblastoma cells. RESULTS: Following exposure to chemotherapeutic drugs, PCNC showed less sensitivity to drugs. No significant changes observed in the p53 expression, whereas Bcl-2 expression was found to be increased in the drug resistant cells as well as in PCNC. Increased expression of P-glycoprotein (P-gp was observed in drug resistant Y79 cells; however there was no significant change in the expression of P-gp found between primary cultures of primarily enucleated eyes and PCNC. Multidrug resistance protein 1 (Mrp-1 expression was found to be elevated in the drug resistant Y79 cells as well as in PCNC. No significant change in the expression of lung resistance associated protein (Lrp was observed in the drug resistant Y79 cells as well as in PCNC. CONCLUSION: Our results suggest that multidrug resistant proteins are intrinsically present in retinoblastoma which causes treatment failure in managing retinoblastoma with chemotherapy.

Expression of multidrug resistance proteins in retinoblastoma.

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Shukla, Swati; Srivastava, Arpna; Kumar, Sunil; Singh, Usha; Goswami, Sandeep; Chawla, Bhavna; Bajaj, Mandeep Singh; Kashyap, Seema; Kaur, Jasbir

2017-01-01

To elucidate the mechanism of multidrug resistance in retinoblastoma, and to acquire more insights into in vivo drug resistance. Three anticancer drug resistant Y79 human RB cells were generated against vincristine, etoposide or carboplatin, which are used for conventional chemotherapy in RB. Primary cultures from enucleated eyes after chemotherapy (PCNC) were also prepared. Their chemosensitivity to chemotherapeutic agents (vincristine, etoposide and carboplatin) were measured using MTT assay. Western blot analysis was performed to evaluate the expression of p53, Bcl-2 and various multidrug resistant proteins in retinoblastoma cells. Following exposure to chemotherapeutic drugs, PCNC showed less sensitivity to drugs. No significant changes observed in the p53 expression, whereas Bcl-2 expression was found to be increased in the drug resistant cells as well as in PCNC. Increased expression of P-glycoprotein (P-gp) was observed in drug resistant Y79 cells; however there was no significant change in the expression of P-gp found between primary cultures of primarily enucleated eyes and PCNC. Multidrug resistance protein 1 (Mrp-1) expression was found to be elevated in the drug resistant Y79 cells as well as in PCNC. No significant change in the expression of lung resistance associated protein (Lrp) was observed in the drug resistant Y79 cells as well as in PCNC. Our results suggest that multidrug resistant proteins are intrinsically present in retinoblastoma which causes treatment failure in managing retinoblastoma with chemotherapy.

Expression of multidrug resistance proteins in retinoblastoma

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Shukla, Swati; Srivastava, Arpna; Kumar, Sunil; Singh, Usha; Goswami, Sandeep; Chawla, Bhavna; Bajaj, Mandeep Singh; Kashyap, Seema; Kaur, Jasbir

2017-01-01

AIM To elucidate the mechanism of multidrug resistance in retinoblastoma, and to acquire more insights into in vivo drug resistance. METHODS Three anticancer drug resistant Y79 human RB cells were generated against vincristine, etoposide or carboplatin, which are used for conventional chemotherapy in RB. Primary cultures from enucleated eyes after chemotherapy (PCNC) were also prepared. Their chemosensitivity to chemotherapeutic agents (vincristine, etoposide and carboplatin) were measured using MTT assay. Western blot analysis was performed to evaluate the expression of p53, Bcl-2 and various multidrug resistant proteins in retinoblastoma cells. RESULTS Following exposure to chemotherapeutic drugs, PCNC showed less sensitivity to drugs. No significant changes observed in the p53 expression, whereas Bcl-2 expression was found to be increased in the drug resistant cells as well as in PCNC. Increased expression of P-glycoprotein (P-gp) was observed in drug resistant Y79 cells; however there was no significant change in the expression of P-gp found between primary cultures of primarily enucleated eyes and PCNC. Multidrug resistance protein 1 (Mrp-1) expression was found to be elevated in the drug resistant Y79 cells as well as in PCNC. No significant change in the expression of lung resistance associated protein (Lrp) was observed in the drug resistant Y79 cells as well as in PCNC. CONCLUSION Our results suggest that multidrug resistant proteins are intrinsically present in retinoblastoma which causes treatment failure in managing retinoblastoma with chemotherapy. PMID:29181307

Cacao families and parents selected as resistant to natural infection of Moniliophthora perniciosa

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Carolina S. Benjamin

2016-07-01

Full Text Available The known sources of resistance to witches’ broom (WB, a severe disease of cacao, are limited. Aiming to identify families and parents resistant to Moniliophthora perniciosa, a population of 22 families was evaluated by assessing the number of brooms formed per tree during 10 years under field conditions. The population was established in randomized blocks with three replications of 12 plants each. Significant differences were observed among families. The most outstanding families were NA33 x RB39 and RB39 x P4B, which presented the lowest WB incidence during 10 years. The increase in natural field infection of Scavina clones families and their descendants were clearly demonstrated after 2006. The existence of additive effects for resistance appears clearly for families, which had other source of resistance associated with Scavina. Clones RB39, RB36, P4B, NA33 and CSUL3 are promising parents for pyramiding resistance genes and increasing the stability and durability of resistance to WB.

Molecular evidence and functional expression of multidrug resistance associated protein (MRP) in rabbit corneal epithelial cells.

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Karla, Pradeep K; Pal, Dananjay; Mitra, Ashim K

2007-01-01

Multidrug resistance associated protein (MRP) is a major family of efflux transporters involved in drug efflux leading to drug resistance. The objective of this study was to explore physical barriers for ocular drug absorption and to verify if the role of efflux transporters. MRP-2 is a major homologue of MRP family and found to express on the apical side of cell membrane. Cultured Rabbit Corneal Epithelial Cells (rCEC) were selected as an in vitro model for corneal epithelium. [14C]-erythromycin which is a proven substrate for MRP-2 was selected as a model drug for functional expression studies. MK-571, a known specific and potent inhibitor for MRP-2 was added to inhibit MRP mediated efflux. Membrane fraction of rCEC was used for western blot analysis. Polarized transport of [14C]-erythromycin was observed in rCEC and transport from B-->A was significantly high than from A-->B. Permeability's increased significantly from A-->B in the presence of MK-571 and ketoconozole. Uptake of [14C]-erythromycin in the presence of MK-571 was significantly higher than control in rCEC. RT-PCR analysis indicated a unique and distinct band at approximately 498 bp corresponding to MRP-2 in rCEC and MDCK11-MRP-2 cells. Immunoprecipitation followed by Western Blot analysis indicated a specific band at approximately 190 kDa in membrane fraction of rCEC and MDCK11-MRP-2 cells. For the first time we have demonstrated high expression of MRP-2 in rabbit corneal epithelium and its functional activity causing drug efflux. RT-PCR, immunoprecipitation followed by Western blot analysis further confirms the result.

The PANTHER database of protein families, subfamilies, functions and pathways

OpenAIRE

Mi, Huaiyu; Lazareva-Ulitsky, Betty; Loo, Rozina; Kejariwal, Anish; Vandergriff, Jody; Rabkin, Steven; Guo, Nan; Muruganujan, Anushya; Doremieux, Olivier; Campbell, Michael J.; Kitano, Hiroaki; Thomas, Paul D.

2004-01-01

PANTHER is a large collection of protein families that have been subdivided into functionally related subfamilies, using human expertise. These subfamilies model the divergence of specific functions within protein families, allowing more accurate association with function (ontology terms and pathways), as well as inference of amino acids important for functional specificity. Hidden Markov models (HMMs) are built for each family and subfamily for classifying additional protein sequences. The l...

Proteomics-based identification of midgut proteins correlated with Cry1Ac resistance in Plutella xylostella (L.).

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Xia, Jixing; Guo, Zhaojiang; Yang, Zezhong; Zhu, Xun; Kang, Shi; Yang, Xin; Yang, Fengshan; Wu, Qingjun; Wang, Shaoli; Xie, Wen; Xu, Weijun; Zhang, Youjun

2016-09-01

The diamondback moth, Plutella xylostella (L.), is a worldwide pest of cruciferous crops and can rapidly develop resistance to many chemical insecticides. Although insecticidal crystal proteins (i.e., Cry and Cyt toxins) derived from Bacillus thuringiensis (Bt) have been useful alternatives to chemical insecticides for the control of P. xylostella, resistance to Bt in field populations of P. xylostella has already been reported. A better understanding of the resistance mechanisms to Bt should be valuable in delaying resistance development. In this study, the mechanisms underlying P. xylostella resistance to Bt Cry1Ac toxin were investigated using two-dimensional differential in-gel electrophoresis (2D-DIGE) and ligand blotting for the first time. Comparative analyses of the constitutive expression of midgut proteins in Cry1Ac-susceptible and -resistant P. xylostella larvae revealed 31 differentially expressed proteins, 21 of which were identified by mass spectrometry. Of these identified proteins, the following fell into diverse eukaryotic orthologous group (KOG) subcategories may be involved in Cry1Ac resistance in P. xylostella: ATP-binding cassette (ABC) transporter subfamily G member 4 (ABCG4), trypsin, heat shock protein 70 (HSP70), vacuolar H(+)-ATPase, actin, glycosylphosphatidylinositol anchor attachment 1 protein (GAA1) and solute carrier family 30 member 1 (SLC30A1). Additionally, ligand blotting identified the following midgut proteins as Cry1Ac-binding proteins in Cry1Ac-susceptible P. xylostella larvae: ABC transporter subfamily C member 1 (ABCC1), solute carrier family 36 member 1 (SLC36A1), NADH dehydrogenase iron-sulfur protein 3 (NDUFS3), prohibitin and Rap1 GTPase-activating protein 1. Collectively, these proteomic results increase our understanding of the molecular resistance mechanisms to Bt Cry1Ac toxin in P. xylostella and also demonstrate that resistance to Bt Cry1Ac toxin is complex and multifaceted. Copyright © 2016 Elsevier B.V. All

Bactobolin resistance is conferred by mutations in the L2 ribosomal protein.

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Chandler, Josephine R; Truong, Thao T; Silva, Patricia M; Seyedsayamdost, Mohammad R; Carr, Gavin; Radey, Matthew; Jacobs, Michael A; Sims, Elizabeth H; Clardy, Jon; Greenberg, E Peter

2012-12-18

Burkholderia thailandensis produces a family of polyketide-peptide molecules called bactobolins, some of which are potent antibiotics. We found that growth of B. thailandensis at 30°C versus that at 37°C resulted in increased production of bactobolins. We purified the three most abundant bactobolins and determined their activities against a battery of bacteria and mouse fibroblasts. Two of the three compounds showed strong activities against both bacteria and fibroblasts. The third analog was much less potent in both assays. These results suggested that the target of bactobolins might be conserved across bacteria and mammalian cells. To learn about the mechanism of bactobolin activity, we isolated four spontaneous bactobolin-resistant Bacillus subtilis mutants. We used genomic sequencing technology to show that each of the four resistant variants had mutations in rplB, which codes for the 50S ribosome-associated L2 protein. Ectopic expression of a mutant rplB gene in wild-type B. subtilis conferred bactobolin resistance. Finally, the L2 mutations did not confer resistance to other antibiotics known to interfere with ribosome function. Our data indicate that bactobolins target the L2 protein or a nearby site and that this is not the target of other antibiotics. We presume that the mammalian target of bactobolins involves the eukaryotic homolog of L2 (L8e). Currently available antibiotics target surprisingly few cellular functions, and there is a need to identify novel antibiotic targets. We have been interested in the Burkholderia thailandensis bactobolins, and we sought to learn about the target of bactobolin activity by mapping spontaneous resistance mutations in the bactobolin-sensitive Bacillus subtilis. Our results indicate that the bactobolin target is the 50S ribosome-associated L2 protein or a region of the ribosome affected by L2. Bactobolin-resistant mutants are not resistant to other known ribosome inhibitors. Our evidence indicates that bactobolins

The stress protein BAG3 stabilizes Mcl-1 protein and promotes survival of cancer cells and resistance to antagonist ABT-737.

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Boiani, Mariana; Daniel, Cristina; Liu, Xueyuan; Hogarty, Michael D; Marnett, Lawrence J

2013-03-08

Members of the Bcl-2 family of proteins are important inhibitors of apoptosis in human cancer and are targets for novel anticancer agents such as the Bcl-2 antagonists, ABT-263 (Navitoclax), and its analog ABT-737. Unlike Bcl-2, Mcl-1 is not antagonized by ABT-263 or ABT-737 and is considered to be a major factor in resistance. Also, Mcl-1 exhibits differential regulation when compared with other Bcl-2 family members and is a target for anticancer drug discovery. Here, we demonstrate that BAG3, an Hsp70 co-chaperone, protects Mcl-1 from proteasomal degradation, thereby promoting its antiapoptotic activity. Using neuroblastoma cell lines, with a defined Bcl-2 family dependence, we found that BAG3 expression correlated with Mcl-1 dependence and ABT-737 resistance. RNA silencing of BAG3 led to a marked reduction in Mcl-1 protein levels and overcame ABT-737 resistance in Mcl-1-dependent cells. In ABT-737-resistant cells, Mcl-1 co-immunoprecipitated with BAG3, and loss of Mcl-1 after BAG3 silencing was prevented by proteasome inhibition. BAG3 and Mcl-1 were co-expressed in a panel of diverse cancer cell lines resistant to ABT-737. Silencing BAG3 reduced Mcl-1 protein levels and overcame ABT-737 resistance in several of the cell lines, including triple-negative breast cancer (MDA-MB231) and androgen receptor-negative prostate cancer (PC3) cells. These studies identify BAG3-mediated Mcl-1 stabilization as a potential target for cancer drug discovery.

The Stress Protein BAG3 Stabilizes Mcl-1 Protein and Promotes Survival of Cancer Cells and Resistance to Antagonist ABT-737*

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Boiani, Mariana; Daniel, Cristina; Liu, Xueyuan; Hogarty, Michael D.; Marnett, Lawrence J.

2013-01-01

Members of the Bcl-2 family of proteins are important inhibitors of apoptosis in human cancer and are targets for novel anticancer agents such as the Bcl-2 antagonists, ABT-263 (Navitoclax), and its analog ABT-737. Unlike Bcl-2, Mcl-1 is not antagonized by ABT-263 or ABT-737 and is considered to be a major factor in resistance. Also, Mcl-1 exhibits differential regulation when compared with other Bcl-2 family members and is a target for anticancer drug discovery. Here, we demonstrate that BAG3, an Hsp70 co-chaperone, protects Mcl-1 from proteasomal degradation, thereby promoting its antiapoptotic activity. Using neuroblastoma cell lines, with a defined Bcl-2 family dependence, we found that BAG3 expression correlated with Mcl-1 dependence and ABT-737 resistance. RNA silencing of BAG3 led to a marked reduction in Mcl-1 protein levels and overcame ABT-737 resistance in Mcl-1-dependent cells. In ABT-737-resistant cells, Mcl-1 co-immunoprecipitated with BAG3, and loss of Mcl-1 after BAG3 silencing was prevented by proteasome inhibition. BAG3 and Mcl-1 were co-expressed in a panel of diverse cancer cell lines resistant to ABT-737. Silencing BAG3 reduced Mcl-1 protein levels and overcame ABT-737 resistance in several of the cell lines, including triple-negative breast cancer (MDA-MB231) and androgen receptor-negative prostate cancer (PC3) cells. These studies identify BAG3-mediated Mcl-1 stabilization as a potential target for cancer drug discovery. PMID:23341456

The ABC gene family in arthropods: comparative genomics and role in insecticide transport and resistance.

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Dermauw, Wannes; Van Leeuwen, Thomas

2014-02-01

About a 100 years ago, the Drosophila white mutant marked the birth of Drosophila genetics. The white gene turned out to encode the first well studied ABC transporter in arthropods. The ABC gene family is now recognized as one of the largest transporter families in all kingdoms of life. The majority of ABC proteins function as primary-active transporters that bind and hydrolyze ATP while transporting a large diversity of substrates across lipid membranes. Although extremely well studied in vertebrates for their role in drug resistance, less is known about the role of this family in the transport of endogenous and exogenous substances in arthropods. The ABC families of five insect species, a crustacean and a chelicerate have been annotated in some detail. We conducted a thorough phylogenetic analysis of the seven arthropod and human ABC protein subfamilies, to infer orthologous relationships that might suggest conserved function. Most orthologous relationships were found in the ABCB half transporter, ABCD, ABCE and ABCF subfamilies, but specific expansions within species and lineages are frequently observed and discussed. We next surveyed the role of ABC transporters in the transport of xenobiotics/plant allelochemicals and their involvement in insecticide resistance. The involvement of ABC transporters in xenobiotic resistance in arthropods is historically not well documented, but an increasing number of studies using unbiased differential gene expression analysis now points to their importance. We give an overview of methods that can be used to link ABC transporters to resistance. ABC proteins have also recently been implicated in the mode of action and resistance to Bt toxins in Lepidoptera. Given the enormous interest in Bt toxicology in transgenic crops, such findings will provide an impetus to further reveal the role of ABC transporters in arthropods. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

Association between insulin resistance and c-reactive protein among Peruvian adults

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Gelaye Bizu

2010-05-01

Full Text Available Abstract Objective Insulin resistance (IR, a reduced physiological response of peripheral tissues to the action of insulin, is one of the major causes of type 2 diabetes. We sought to evaluate the relationship between serum C-reactive protein (CRP, a marker of systemic inflammation, and prevalence of IR among Peruvian adults. Methods This population based study of 1,525 individuals (569 men and 956 women; mean age 39 years old was conducted among residents in Lima and Callao, Peru. Fasting plasma glucose, insulin, and CRP concentrations were measured using standard approaches. Insulin resistance was assessed using the homeostasis model (HOMA-IR. Categories of CRP were defined by the following tertiles: 2.53 mg/l. Logistic regression procedures were employed to estimate odds ratios (OR and 95% confidence intervals (CI. Results Elevated CRP were significantly associated with increased mean fasting insulin and mean HOMA-IR concentrations (p 2.53 mg/l (upper tertile had a 2.18-fold increased risk of IR (OR = 2.18 95% CI 1.51-3.16 as compared with those in the lowest tertile ( Conclusion Our observations among Peruvians suggest that chronic systemic inflammation, as evidenced by elevated CRP, may be of etiologic importance in insulin resistance and diabetes.

Phylogenetic distribution and membrane topology of the LytR-CpsA-Psr protein family

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Berger-Bächi Brigitte

2008-12-01

Full Text Available Abstract Background The bacterial cell wall is the target of many antibiotics and cell envelope constituents are critical to host-pathogen interactions. To combat resistance development and virulence, a detailed knowledge of the individual factors involved is essential. Members of the LytR-CpsA-Psr family of cell envelope-associated attenuators are relevant for β-lactam resistance, biofilm formation, and stress tolerance, and they are suggested to play a role in cell wall maintenance. However, their precise function is still unknown. This study addresses the occurrence as well as sequence-based characteristics of the LytR-CpsA-Psr proteins. Results A comprehensive list of LytR-CpsA-Psr proteins was established, and their phylogenetic distribution and clustering into subgroups was determined. LytR-CpsA-Psr proteins were present in all Gram-positive organisms, except for the cell wall-deficient Mollicutes and one strain of the Clostridiales. In contrast, the majority of Gram-negatives did not contain LytR-CpsA-Psr family members. Despite high sequence divergence, the LytR-CpsA-Psr domains of different subclusters shared a highly similar, predicted mixed a/β-structure, and conserved charged residues. PhoA fusion experiments, using MsrR of Staphylococcus aureus, confirmed membrane topology predictions and extracellular location of its LytR-CpsA-Psr domain. Conclusion The LytR-CpsA-Psr domain is unique to bacteria. The presence of diverse subgroups within the LytR-CpsA-Psr family might indicate functional differences, and could explain variations in phenotypes of respective mutants reported. The identified conserved structural elements and amino acids are likely to be important for the function of the domain and will help to guide future studies of the LytR-CpsA-Psr proteins.

Anti-protein C antibodies are associated with resistance to endogenous protein C activation and a severe thrombotic phenotype in antiphospholipid syndrome.

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Arachchillage, D R J; Efthymiou, M; Mackie, I J; Lawrie, A S; Machin, S J; Cohen, H

2014-11-01

Antiphospholipid antibodies may interfere with the anticoagulant activity of activated protein C (APC) to induce acquired APC resistance (APCr). To investigate the frequency and characteristics of APCr by using recombinant human APC (rhAPC) and endogenous protein C activation in antiphospholipid syndrome (APS). APCr was assessed in APS and non-APS venous thromboembolism (VTE) patients on warfarin and normal controls with rhAPC or Protac by thrombin generation. IgG anti-protein C and anti-protein S antibodies and avidity were assessed by ELISA. APS patients showed greater resistance to both rhAPC and Protac than non-APS patients and normal controls (median normalized endogenous thrombin potential inhibition): APS patients with rhAPC, 81.3% (95% confidence interval [CI] 75.2-88.3%; non-APS patients with rhAPC, 97.7% (95% CI 93.6-101.8%; APS patients with Protac, 66.0% (95% CI 59.5-72.6%); and non-APS patients with Protac, 80.7 (95% CI 74.2-87.2%). APS patients also had a higher frequency and higher levels of anti-protein C antibodies, with 60% (15/25) high-avidity antibodies. High-avidity anti-protein C antibodies were associated with greater APCr and with a severe thrombotic phenotype (defined as the development of recurrent VTE while patients were receiving therapeutic anticoagulation or both venous and arterial thrombosis). Twelve of 15 (80%) patients with high-avidity anti-protein C antibodies were classified as APS category I. Thrombotic APS patients showed greater APCr to both rhAPC and activation of endogenous protein C by Protac. High-avidity anti-protein C antibodies, associated with greater APCr, may provide a marker for a severe thrombotic phenotype in APS. However, in patients with category I APS, it remains to be established whether anti-protein C or anti-β2 -glycoprotein I antibodies are responsible for APCr. © 2014 International Society on Thrombosis and Haemostasis.

Putative resistance gene markers associated with quantitative trait loci for fire blight resistance in Malus ‘Robusta 5’ accessions

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2012-01-01

Background Breeding of fire blight resistant scions and rootstocks is a goal of several international apple breeding programs, as options are limited for management of this destructive disease caused by the bacterial pathogen Erwinia amylovora. A broad, large-effect quantitative trait locus (QTL) for fire blight resistance has been reported on linkage group 3 of Malus ‘Robusta 5’. In this study we identified markers derived from putative fire blight resistance genes associated with the QTL by integrating further genetic mapping studies with bioinformatics analysis of transcript profiling data and genome sequence databases. Results When several defined E.amylovora strains were used to inoculate three progenies from international breeding programs, all with ‘Robusta 5’ as a common parent, two distinct QTLs were detected on linkage group 3, where only one had previously been mapped. In the New Zealand ‘Malling 9’ X ‘Robusta 5’ population inoculated with E. amylovora ICMP11176, the proximal QTL co-located with SNP markers derived from a leucine-rich repeat, receptor-like protein ( MxdRLP1) and a closely linked class 3 peroxidase gene. While the QTL detected in the German ‘Idared’ X ‘Robusta 5’ population inoculated with E. amylovora strains Ea222_JKI or ICMP11176 was approximately 6 cM distal to this, directly below a SNP marker derived from a heat shock 90 family protein gene ( HSP90). In the US ‘Otawa3’ X ‘Robusta5’ population inoculated with E. amylovora strains Ea273 or E2002a, the position of the LOD score peak on linkage group 3 was dependent upon the pathogen strains used for inoculation. One of the five MxdRLP1 alleles identified in fire blight resistant and susceptible cultivars was genetically associated with resistance and used to develop a high resolution melting PCR marker. A resistance QTL detected on linkage group 7 of the US population co-located with another HSP90 gene-family member and a WRKY transcription factor

Hepatic steatosis does not cause insulin resistance in people with familial hypobetalipoproteinaemia

NARCIS (Netherlands)

Visser, M. E.; Lammers, N. M.; Nederveen, A. J.; van der Graaf, M.; Heerschap, A.; Ackermans, M. T.; Sauerwein, H. P.; Stroes, E. S.; Serlie, M. J.

2011-01-01

Hepatic steatosis is strongly associated with hepatic and whole-body insulin resistance. It has proved difficult to determine whether hepatic steatosis itself is a direct cause of insulin resistance. In patients with familial hypobetalipoproteinaemia (FHBL), hepatic steatosis is a direct consequence

Bioinformatics and structural characterization of a hypothetical protein from Streptococcus mutans: implication of antibiotic resistance.

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Jie Nan

2009-10-01

Full Text Available As an oral bacterial pathogen, Streptococcus mutans has been known as the aetiologic agent of human dental caries. Among a total of 1960 identified proteins within the genome of this organism, there are about 500 without any known functions. One of these proteins, SMU.440, has very few homologs in the current protein databases and it does not fall into any protein functional families. Phylogenetic studies showed that SMU.440 is related to a particular ecological niche and conserved specifically in some oral pathogens, due to lateral gene transfer. The co-occurrence of a MarR protein within the same operon among these oral pathogens suggests that SMU.440 may be associated with antibiotic resistance. The structure determination of SMU.440 revealed that it shares the same fold and a similar pocket as polyketide cyclases, which indicated that it is very likely to bind some polyketide-like molecules. From the interlinking structural and bioinformatics studies, we have concluded that SMU.440 could be involved in polyketide-like antibiotic resistance, providing a better understanding of this hypothetical protein. Besides, the combination of multiple methods in this study can be used as a general approach for functional studies of a protein with unknown function.

Crystal Structure of the Zorbamycin-Binding Protein ZbmA, the Primary Self-Resistance Element in Streptomyces flavoviridis ATCC21892

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Rudolf, Jeffrey D. [Scripps Research Inst., Jupiter, FL (United States); Bigelow, Lance [Argonne National Lab. (ANL), Argonne, IL (United States); Chang, Changsoo [Argonne National Lab. (ANL), Argonne, IL (United States); Cuff, Marianne E. [Argonne National Lab. (ANL), Argonne, IL (United States); Lohman, Jeremy R. [Scripps Research Inst., Jupiter, FL (United States); Chang, Chin-Yuan [Scripps Research Inst., Jupiter, FL (United States); Ma, Ming [Scripps Research Inst., Jupiter, FL (United States); Yang, Dong [Scripps Research Inst., Jupiter, FL (United States); Clancy, Shonda [Argonne National Lab. (ANL), Argonne, IL (United States); Babnigg, Gyorgy [Argonne National Lab. (ANL), Argonne, IL (United States); Joachimiak, Andrzej [Argonne National Lab. (ANL), Argonne, IL (United States); Phillips, George N. [Rice Univ., Houston, TX (United States); Shen, Ben [Scripps Research Inst., Jupiter, FL (United States)

2015-11-17

The bleomycins (BLMs), tallysomycins (TLMs), phleomycin, and zorbamycin (ZBM) are members of the BLM family of glycopeptide-derived antitumor antibiotics. The BLM-producing Streptomyces verticillus ATCC15003 and the TLM-producing Streptoalloteichus hindustanus E465-94 ATCC31158 both possess at least two self-resistance elements, an N-acetyltransferase and a binding protein. The N-acetyltransferase provides resistance by disrupting the metal-binding domain of the antibiotic that is required for activity, while the binding protein confers resistance by sequestering the metal-bound antibiotic and preventing drug activation via molecular oxygen. We recently established that the ZBM producer, Streptomyces flavoviridis ATCC21892, lacks the N-acetyltransferase resistance gene and that the ZBM-binding protein, ZbmA, is sufficient to confer resistance in the producing strain. To investigate the resistance mechanism attributed to ZbmA, we determined the crystal structures of apo and Cu(II)-ZBM-bound ZbmA at high resolutions of 1.90 and 1.65 angstrom, respectively. A comparison and contrast with other structurally characterized members of the BLM-binding protein family revealed key differences in the protein ligand binding environment that fine-tunes the ability of ZbmA to sequester metal-bound ZBM and supports drug sequestration as the primary resistance mechanism in the producing organisms of the BLM family of antitumor antibiotics.

Decreased PARP and procaspase-2 protein levels are associated with cellular drug resistance in childhood acute lymphoblastic leukemia

NARCIS (Netherlands)

A. Holleman (Amy); M.L. den Boer (Monique); K.M. Kazemier (Karin); H.B. Beverloo (Berna); A.R.M. von Bergh (Anne); G.E. Janka-Schaub (Gritta); R. Pieters (Rob)

2005-01-01

textabstractDrug resistance in childhood acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML) is associated with impaired ability to induce apoptosis. To elucidate causes of apoptotic defects, we studied the protein expression of Apaf-1, procaspases-2, -3, -6, -7,

INS VNTR is not associated with childhood obesity in 1,023 families: a family-based study.

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Bouatia-Naji, Nabila; De Graeve, Franck; Brönner, Günter; Lecoeur, Cécile; Vatin, Vincent; Durand, Emmanuelle; Lichtner, Peter; Nguyen, Thuy T; Heude, Barbara; Weill, Jacques; Lévy-Marchal, Claire; Hebebrand, Johannes; Froguel, Philippe; Meyre, David

2008-06-01

Previous studies have described genetic associations of the insulin gene variable number tandem repeat (INS VNTR) variant with childhood obesity and associated phenotypes. We aimed to assess the contribution of INS VNTR genotypes to childhood obesity and variance of insulin resistance, insulin secretion, and birth weight using family-based design. Participants were either French or German whites. We used transmission disequilibrium tests (TDTs) for assessing binary traits and quantitative pedigree disequilibrium tests for assessing continuous traits. In contrast to previous findings, we did not observe any familial association with childhood obesity (T = 50%, P = 0.77) in the 1,023 families tested. In French obese children, INS VNTR did not associate with fasting insulin levels (P = 0.23) and class I allele showed only borderline association with increased insulin secretion index at 30 min (P = 0.03). INS VNTR did not associate with birth weight in obese children (P = 0.98) and TDT analyses in 350 French families with history of low birth weight (LBW) showed no association with this condition (P = 0.92). In summary, our study, the largest performed so far, does not support the previously reported associations between INS VNTR and childhood obesity, insulin resistance, or birth weight, and does not suggest any major role for this variant in modulating these traits.

Salivary gland proteome analysis reveals modulation of anopheline unique proteins in insensitive acetylcholinesterase resistant Anopheles gambiae mosquitoes.

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Sylvie Cornelie

Full Text Available Insensitive acetylcholinesterase resistance due to a mutation in the acetylcholinesterase (ace encoding ace-1 gene confers cross-resistance to organophosphate and carbamate insecticides in Anopheles gambiae populations from Central and West Africa. This mutation is associated with a strong genetic cost revealed through alterations of some life history traits but little is known about the physiological and behavioural changes in insects bearing the ace-1(R allele. Comparative analysis of the salivary gland contents between An. gambiae susceptible and ace-1(R resistant strains was carried out to charaterize factors that could be involved in modifications of blood meal process, trophic behaviour or pathogen interaction in the insecticide-resistant mosquitoes. Differential analysis of the salivary gland protein profiles revealed differences in abundance for several proteins, two of them showing major differences between the two strains. These two proteins identified as saglin and TRIO are salivary gland-1 related proteins, a family unique to anopheline mosquitoes, one of them playing a crucial role in salivary gland invasion by Plasmodium falciparum sporozoites. Differential expression of two other proteins previously identified in the Anopheles sialome was also observed. The differentially regulated proteins are involved in pathogen invasion, blood feeding process, and protection against oxidation, relevant steps in the outcome of malaria infection. Further functional studies and insect behaviour experiments would confirm the impact of the modification of the sialome composition on blood feeding and pathogen transmission abilities of the resistant mosquitoes. The data supports the hypothesis of alterations linked to insecticide resistance in the biology of the primary vector of human malaria in Africa.

Finding Relational Associations in HIV Resistance Mutation Data

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Richter, Lothar; Augustin, Regina; Kramer, Stefan

HIV therapy optimization is a hard task due to rapidly evolving mutations leading to drug resistance. Over the past five years, several machine learning approaches have been developed for decision support, mostly to predict therapy failure from the genotypic sequence of viral proteins and additional factors. In this paper, we define a relational representation for an important part of the data, namely the sequences of a viral protein (reverse transcriptase), their mutations, and the drug resistance(s) associated with those mutations. The data were retrieved from the Los Alamos National Laboratories' (LANL) HIV databases. In contrast to existing work in this area, we do not aim directly for predictive modeling, but take one step back and apply descriptive mining methods to develop a better understanding of the correlations and associations between mutations and resistances. In our particular application, we use the Warmr algorithm to detect non-trivial patterns connecting mutations and resistances. Our findings suggest that well-known facts can be rediscovered, but also hint at the potential of discovering yet unknown associations.

Detergent-associated solution conformations of helical and beta-barrel membrane proteins.

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Mo, Yiming; Lee, Byung-Kwon; Ankner, John F; Becker, Jeffrey M; Heller, William T

2008-10-23

Membrane proteins present major challenges for structural biology. In particular, the production of suitable crystals for high-resolution structural determination continues to be a significant roadblock for developing an atomic-level understanding of these vital cellular systems. The use of detergents for extracting membrane proteins from the native membrane for either crystallization or reconstitution into model lipid membranes for further study is assumed to leave the protein with the proper fold with a belt of detergent encompassing the membrane-spanning segments of the structure. Small-angle X-ray scattering was used to probe the detergent-associated solution conformations of three membrane proteins, namely bacteriorhodopsin (BR), the Ste2p G-protein coupled receptor from Saccharomyces cerevisiae, and the Escherichia coli porin OmpF. The results demonstrate that, contrary to the traditional model of a detergent-associated membrane protein, the helical proteins BR and Ste2p are not in the expected, compact conformation and associated with detergent micelles, while the beta-barrel OmpF is indeed embedded in a disk-like micelle in a properly folded state. The comparison provided by the BR and Ste2p, both members of the 7TM family of helical membrane proteins, further suggests that the interhelical interactions between the transmembrane helices of the two proteins differ, such that BR, like other rhodopsins, can properly refold to crystallize, while Ste2p continues to prove resistant to crystallization from an initially detergent-associated state.

Distinct roles of the RasGAP family proteins in C. elegans associative learning and memory.

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Gyurkó, M Dávid; Csermely, Péter; Sőti, Csaba; Steták, Attila

2015-10-15

The Ras GTPase activating proteins (RasGAPs) are regulators of the conserved Ras/MAPK pathway. Various roles of some of the RasGAPs in learning and memory have been reported in different model systems, yet, there is no comprehensive study to characterize all gap genes in any organism. Here, using reverse genetics and neurobehavioural tests, we studied the role of all known genes of the rasgap family in C. elegans in associative learning and memory. We demonstrated that their proteins are implicated in different parts of the learning and memory processes. We show that gap-1 contribute redundantly with gap-3 to the chemosensation of volatile compounds, gap-1 plays a major role in associative learning, while gap-2 and gap-3 are predominantly required for short- and long-term associative memory. Our results also suggest that the C. elegans Ras orthologue let-60 is involved in multiple processes during learning and memory. Thus, we show that the different classes of RasGAP proteins are all involved in cognitive function and their complex interplay ensures the proper formation and storage of novel information in C. elegans.

XA23 is an executor R protein and confers broad-spectrum disease resistance in rice.

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Wang, Chunlian; Zhang, Xiaoping; Fan, Yinglun; Gao, Ying; Zhu, Qinlong; Zheng, Chongke; Qin, Tengfei; Li, Yanqiang; Che, Jinying; Zhang, Mingwei; Yang, Bing; Liu, Yaoguang; Zhao, Kaijun

2014-11-09

The majority of plant disease resistance (R) genes encode proteins that share common structural features. However, the transcription activator-like effector (TALE) associated executor type R genes show no considerable sequence homology to any known R genes. We adopted a map-based cloning approach and TALE-based technology to isolate and characterize Xa23, a new executor R gene derived from the wild rice (Oryza rufipogon) that confers an extremely broad spectrum of resistance to bacterial blight caused by Xanthomonas oryzae pv. oryzae (Xoo). Xa23 encodes a 113-amino acid protein that shares 50% identity to the known executor R protein XA10. The predicted transmembrane helices in XA23 also overlap with those of XA10. Unlike Xa10, however, Xa23 transcription is specifically activated by AvrXa23, a TALE present in all examined Xoo field isolates. Moreover, the susceptible xa23 allele has an identical open reading frame of Xa23, but differs in promoter region by lacking the TALE binding-element (EBE) for AvrXa23. XA23 can trigger strong hypersensitive response in rice, tobacco and tomato. Our results provide the first evidence that plant genomes have an executor R gene family in which members execute their function and spectrum of disease resistance by recognizing the cognate TALEs in pathogen. © The Author 2014. Published by the Molecular Plant Shanghai Editorial Office in association with Oxford University Press on behalf of CSPB and IPPE, SIBS, CAS.

Coexpression of multidrug resistance involve proteins: a flow cytometric analysis.

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Boutonnat, J; Bonnefoix, T; Mousseau, M; Seigneurin, D; Ronot, X

1998-01-01

Cross resistance to multiple natural cytotoxic products represents a major obstacle in myeloblastic acute leukaemia (AML). Multidrug resistance (MDR) often involves overexpression of plasma membrane drug transporter P-glycoprotein (PGP) or the resistance associated protein (MRP). Recently, a protein overexpressed in a non-PGP MDR lung cancer cell line and termed lung resistance related protein (LRP) was identified. These proteins are known to be associated with a bad prognosis in AML. We have developed a triple indirect labelling analysed by flow cytometry to detect the coexpression of these proteins. Since no cell line expressing all three antigens is known, we mixed K562 cells (resistant to Adriblastine, PGP+, MRP-, LRP-) with GLC4 cells (resistant to Adriblastine, PGP-, MRP+, LRP+) to create a model system to test the method. The antibodies used were UIC2 for PGP, MRPm6 for MRP and LRP56 for LRP. They were revealed by Fab'2 coupled with Fluoresceine-isothiocyanate, Phycoerythrin or Tricolor with isotype specificity. Cells were fixed and permeabilized after PGP labelling because MRPm6 and LRP56 recognize intracellular epitopes. PGP and LRP were easily detected. MRP is expressed at relatively low levels and was more difficult to detect because in the triple labelling the non specific staining was higher than in a single labelling. Despite the increased background in the triple labelling we were able to detect coexpression of PGP, MRP, LRP by flow cytometry. This method appears to be very useful to detect coexpression of markers in AML. Such coexpression could modify the therapeutic approach with revertants.

TIM-family proteins promote infection of multiple enveloped viruses through virion-associated phosphatidylserine.

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Stephanie Jemielity

2013-03-01

Full Text Available Human T-cell Immunoglobulin and Mucin-domain containing proteins (TIM1, 3, and 4 specifically bind phosphatidylserine (PS. TIM1 has been proposed to serve as a cellular receptor for hepatitis A virus and Ebola virus and as an entry factor for dengue virus. Here we show that TIM1 promotes infection of retroviruses and virus-like particles (VLPs pseudotyped with a range of viral entry proteins, in particular those from the filovirus, flavivirus, New World arenavirus and alphavirus families. TIM1 also robustly enhanced the infection of replication-competent viruses from the same families, including dengue, Tacaribe, Sindbis and Ross River viruses. All interactions between TIM1 and pseudoviruses or VLPs were PS-mediated, as demonstrated with liposome blocking and TIM1 mutagenesis experiments. In addition, other PS-binding proteins, such as Axl and TIM4, promoted infection similarly to TIM1. Finally, the blocking of PS receptors on macrophages inhibited the entry of Ebola VLPs, suggesting that PS receptors can contribute to infection in physiologically relevant cells. Notably, infection mediated by the entry proteins of Lassa fever virus, influenza A virus and SARS coronavirus was largely unaffected by TIM1 expression. Taken together our data show that TIM1 and related PS-binding proteins promote infection of diverse families of enveloped viruses, and may therefore be useful targets for broad-spectrum antiviral therapies.

Non-host Plant Resistance against Phytophthora capsici Is Mediated in Part by Members of the I2 R Gene Family in Nicotiana spp.

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Vega-Arreguín, Julio C; Shimada-Beltrán, Harumi; Sevillano-Serrano, Jacobo; Moffett, Peter

2017-01-01

The identification of host genes associated with resistance to Phytophthora capsici is crucial to developing strategies of control against this oomycete pathogen. Since there are few sources of resistance to P. capsici in crop plants, non-host plants represent a promising source of resistance genes as well as excellent models to study P. capsici - plant interactions. We have previously shown that non-host resistance to P. capsici in Nicotiana spp. is mediated by the recognition of a specific P. capsici effector protein, PcAvr3a1 in a manner that suggests the involvement of a cognate disease resistance (R) genes. Here, we have used virus-induced gene silencing (VIGS) and transgenic tobacco plants expressing dsRNA in Nicotiana spp. to identify candidate R genes that mediate non-host resistance to P. capsici . Silencing of members of the I2 multigene family in the partially resistant plant N. edwardsonii and in the resistant N. tabacum resulted in compromised resistance to P. capsici . VIGS of two other components required for R gene-mediated resistance, EDS1 and SGT1 , also enhanced susceptibility to P. capsici in N. edwardsonii , as well as in the susceptible plants N. benthamiana and N. clevelandii . The silencing of I2 family members in N. tabacum also compromised the recognition of PcAvr3a1. These results indicate that in this case, non-host resistance is mediated by the same components normally associated with race-specific resistance.

Increased Prevalence of Activated Protein C Resistance During ...

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Background: Acquired resistance to protein C in pregnancy has been established as one of the factors associated with ..... diabetes, sickle cell disease, smoking, anti-phospholipid syndrome inherited thrombophilia, and previous history of.

Insulin resistance in Chinese patients with type 2 diabetes is associated with C-reactive protein independent of abdominal obesity

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Feng Xiaocheng

2010-12-01

Full Text Available Abstract Background There is debate as to whether the association between C-reactive protein (CRP and insulin resistance is independent of body fatness, particularly central obesity. Therefore, the association among CRP, insulin resistance and obesity was analyzed in Chinese patients with type 2 diabetes. Methods The study included 520 Chinese patients diagnosed with type 2 diabetes with CRP levels not exceeding 10 mg/L. The degree of insulin resistance was determined with the homeostasis model assessment of insulin resistance (HOMA-IR. The CRP levels were categorized into quartiles from the lowest to the highest concentrations (Q1-Q4. Results Body mass index (BMI and waist circumference (WC were both higher in Q4, Q3 and Q2 than those in Q1. HOMA-IR was higher in Q2, Q3 and Q4 than that in Q1 (Q1 vs Q4, P Conclusion These findings showed that insulin resistance was associated with CRP levels independent of abdominal obesity in Chinese patients with type 2 diabetes, suggesting that abdominal obesity could only partly explain the link between subclinical inflammation and insulin resistance.

Structural elucidation of transmembrane domain zero (TMD0) of EcdL: A multidrug resistance-associated protein (MRP) family of ATP-binding cassette transporter protein revealed by atomistic simulation.

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Bera, Krishnendu; Rani, Priyanka; Kishor, Gaurav; Agarwal, Shikha; Kumar, Antresh; Singh, Durg Vijay

2017-09-20

ATP-Binding cassette (ABC) transporters play an extensive role in the translocation of diverse sets of biologically important molecules across membrane. EchnocandinB (antifungal) and EcdL protein of Aspergillus rugulosus are encoded by the same cluster of genes. Co-expression of EcdL and echinocandinB reflects tightly linked biological functions. EcdL belongs to Multidrug Resistance associated Protein (MRP) subfamily of ABC transporters with an extra transmembrane domain zero (TMD0). Complete structure of MRP subfamily comprising of TMD0 domain, at atomic resolution is not known. We hypothesized that the transportation of echonocandinB is mediated via EcdL protein. Henceforth, it is pertinent to know the topological arrangement of TMD0, with other domains of protein and its possible role in transportation of echinocandinB. Absence of effective template for TMD0 domain lead us to model by I-TASSER, further structure has been refined by multiple template modelling using homologous templates of remaining domains (TMD1, NBD1, TMD2, NBD2). The modelled structure has been validated for packing, folding and stereochemical properties. MD simulation for 0.1 μs has been carried out in the biphasic environment for refinement of modelled protein. Non-redundant structures have been excavated by clustering of MD trajectory. The structural alignment of modelled structure has shown Z-score -37.9; 31.6, 31.5 with RMSD; 2.4, 4.2, 4.8 with ABC transporters; PDB ID 4F4C, 4M1 M, 4M2T, respectively, reflecting the correctness of structure. EchinocandinB has been docked to the modelled as well as to the clustered structures, which reveals interaction of echinocandinB with TMD0 and other TM helices in the translocation path build of TMDs.

A plant Bcl-2-associated athanogene is proteolytically activated to confer fungal resistance

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Mehdi Kabbage

2016-04-01

Full Text Available The Bcl-2-associated athanogene (BAG family is a multifunctional group of proteins involved in numerous cellular functions ranging from apoptosis to tumorigenesis. These proteins are evolutionarily conserved and encode a characteristic region known as the BAG domain. BAGs function as adapter proteins forming complexes with signaling molecules and molecular chaperones. In humans, a role for BAG proteins has been suggested in tumor growth, HIV infection, and neurodegenerative diseases; as a result, the BAGs are attractive targets for therapeutic interventions, and their expression in cells may serve as a predictive tool for disease development. The Arabidopsis genome contains seven homologs of BAG family proteins (Figure 1, including four with a domain organization similar to animal BAGs (BAG1-4. The remaining three members (BAG5-7 contain a predicted calmodulin-binding motif near the BAG domain, a feature unique to plant BAG proteins that possibly reflects divergent mechanisms associated with plant-specific functions. As reported for animal BAGs, plant BAGs also regulate several stress and developmental processes (Figure 2. The recent article by Li et al. focuses on the role of BAG6 in plant innate immunity. This study shows that BAG6 plays a key role in basal plant defense against fungal pathogens. Importantly, this work further shows that BAG6 is proteolytically activated to induce autophagic cell death and resistance in plants. This finding underscores the importance of proteases in the execution of plant cell death, yet little is known about proteases and their substrates in plants.

The putative multidrug resistance protein MRP-7 inhibits methylmercury-associated animal toxicity and dopaminergic neurodegeneration in Caenorhabditis elegans.

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VanDuyn, Natalia; Nass, Richard

2014-03-01

Parkinson's disease (PD) is the most prevalent neurodegenerative motor disorder worldwide, and results in the progressive loss of dopamine (DA) neurons in the substantia nigra pars compacta. Gene-environment interactions are believed to play a significant role in the vast majority of PD cases, yet the toxicants and the associated genes involved in the neuropathology are largely ill-defined. Recent epidemiological and biochemical evidence suggests that methylmercury (MeHg) may be an environmental toxicant that contributes to the development of PD. Here, we report that a gene coding for the putative multidrug resistance protein MRP-7 in Caenorhabditis elegans modulates whole animal and DA neuron sensitivity to MeHg. In this study, we demonstrate that genetic knockdown of MRP-7 results in a twofold increase in Hg levels and a dramatic increase in stress response proteins associated with the endoplasmic reticulum, golgi apparatus, and mitochondria, as well as an increase in MeHg-associated animal death. Chronic exposure to low concentrations of MeHg induces MRP-7 gene expression, while exposures in MRP-7 genetic knockdown animals results in a loss of DA neuron integrity without affecting whole animal viability. Furthermore, transgenic animals expressing a fluorescent reporter behind the endogenous MRP-7 promoter indicate that the transporter is expressed in DA neurons. These studies show for the first time that a multidrug resistance protein is expressed in DA neurons, and its expression inhibits MeHg-associated DA neuron pathology. © 2013 International Society for Neurochemistry.

Expression of GIMAP1, a GTPase of the immunity-associated protein family, is not up-regulated in malaria

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Carter Christine

2009-04-01

Full Text Available Abstract Background GIMAP (GTPase of the immunity-associated protein family proteins are a family of putative GTPases believed to be regulators of cell death in lymphomyeloid cells. GIMAP1 was the first reported member of this gene family, identified as a gene up-regulated at the RNA level in the spleens of mice infected with the malarial parasite, Plasmodium chabaudi. Methods A monoclonal antibody against mouse GIMAP1 was developed and was used to analyse the expression of the endogenous protein in tissues of normal mice and in defined sub-populations of cells prepared from lymphoid tissues using flow cytometry. It was also used to assess the expression of GIMAP1 protein after infection and/or immunization of mice with P. chabaudi. Real-time PCR analysis was employed to measure the expression of GIMAP1 for comparison with the protein level analysis. Results GIMAP1 protein expression was detected in all lineages of lymphocytes (T, B, NK, in F4/80+ splenic macrophages and in some lymphoid cell lines. Additional evidence is presented suggesting that the strong expression by mature B cells of GIMAP1 and other GIMAP genes and proteins seen in mice may be a species-dependent characteristic. Unexpectedly, no increase was found in the expression of GIMAP1 in P. chabaudi infected mice at either the mRNA or protein level, and this remained so despite applying a number of variations to the protocol. Conclusion The model of up-regulation of GIMAP1 in response to infection/immunization with P. chabaudi is not a robustly reproducible experimental system. The GIMAP1 protein is widely expressed in lymphoid cells, with an interesting increase in expression in the later stages of B cell development. Alternative approaches will be required to define the functional role of this GTPase in immune cells.

Targeting the HER family with Pan-HER effectively overcomes resistance to cetuximab

Science.gov (United States)

Iida, Mari; Bahrar, Harsh; Brand, Toni M; Pearson, Hannah E; Coan, John P; Orbuch, Rachel A; Flanigan, Bailey G; Swick, Adam D; Prabakaran, Prashanth; Lantto, Johan; Horak, Ivan D.; Kragh, Michael; Salgia, Ravi; Kimple, Randy J; Wheeler, Deric L

2016-01-01

Cetuximab, an antibody against the Epidermal Growth Factor Receptor (EGFR) has shown efficacy in treating head and neck squamous cell carcinoma (HNSCC), metastatic colorectal cancer and non-small cell lung cancer (NSCLC). Despite the clinical success of cetuximab, many patients do not respond to cetuximab. Furthermore, virtually all patients who do initially respond become refractory, highlighting both intrinsic and acquired resistance to cetuximab as significant clinical problems. To understand mechanistically how cancerous cells acquire resistance, we previously developed models of acquired resistance using the H226 NSCLC and UM-SCC1 HNSCC cell lines. Cetuximab-resistant clones showed a robust upregulation and dependency on the HER family receptors EGFR, HER2 and HER3. Here, we examined Pan-HER, a mixture of six antibodies targeting these receptors on cetuximab-resistant clones. In cells exhibiting acquired or intrinsic resistance to cetuximab, Pan-HER treatment decreased all three receptors’ protein levels and down-stream activation of AKT and MAPK. This correlated with decreased cell proliferation in cetuximab-resistant clones. To determine whether Pan-HER had a therapeutic benefit in vivo, we established de novo cetuximab-resistant mouse xenografts and treated resistant tumors with Pan-HER. This regimen resulted in a superior growth delay of cetuximab-resistant xenografts compared to mice continued on cetuximab. Furthermore, intrinsically cetuximab-resistant HNSCC patient-derived xenograft tumors treated with Pan-HER exhibited significant growth delay compared to vehicle/cetuximab controls. These results suggest that targeting HER family receptors simultaneously with Pan-HER is a promising treatment strategy for tumors displaying intrinsic or acquired resistance to cetuximab. PMID:27422810

Colistin resistance associated with outer membrane protein change in Klebsiella pneumoniae and Enterobacter asburiae.

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Kádár, Béla; Kocsis, Béla; Tóth, Ákos; Kristóf, Katalin; Felső, Péter; Kocsis, Béla; Böddi, Katalin; Szabó, Dóra

2017-06-01

In this study, outer membrane proteins (OMPs) of colistin-resistant Klebsiella pneumoniae and Enterobacter asburiae were analyzed. One colistin-susceptible and three colistin-resistant K. pneumoniae sequence type 258 strains as well as one colistin-susceptible E. asburiae and its colistin-heteroresistant counterpart strain were involved in the study. OMP analysis of each strain was performed by microchip method. Matrix-assisted laser desorption ionization time of flight/mass spectrometry (MALDI-TOF/MS) investigation was carried out after separation of OMPs by two-dimensional gel electrophoresis and in-gel digestion. The MALDI-TOF/MS analysis of OMPs in the colistin-susceptible K. pneumoniae found 16 kDa proteins belonging to the LysM domain/BON superfamily, as well as DNA starvation proteins, whereas OmpX and OmpW were detected in the colistin-resistant counterpart strains. OmpC and OmpW were detected in the colistin-susceptible E. asburiae, whereas OmpA and OmpX were identified in the colistin-resistant counterpart. This study demonstrated that OMP differences were between colistin-susceptible and -resistant counterpart strains. The altered Gram-negative cell wall may contribute to acquired colistin resistance in Enterobacteriaceae.

The tubby family proteins

OpenAIRE

Mukhopadhyay, Saikat; Jackson, Peter K

2011-01-01

The tubby mouse shows a tripartite syndrome characterized by maturity-onset obesity, blindness and deafness. The causative gene Tub is the founding member of a family of related proteins present throughout the animal and plant kingdoms, each characterized by a signature carboxy-terminal tubby domain. This domain consists of a β barrel enclosing a central α helix and binds selectively to specific membrane phosphoinositides. The vertebrate family of tubby-like proteins (TULPs) includes the foun...

Insulin resistance and protein energy metabolism in patients with advanced chronic kidney disease.

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Siew, Edward D; Ikizler, Talat Alp

2010-01-01

Insulin resistance (IR), the reciprocal of insulin sensitivity is a known complication of advanced chronic kidney disease (CKD) and is associated with a number of metabolic derangements. The complex metabolic abnormalities observed in CKD such as vitamin D deficiency, obesity, metabolic acidosis, inflammation, and accumulation of "uremic toxins" are believed to contribute to the etiology of IR and acquired defects in the insulin-receptor signaling pathway in this patient population. Only a few investigations have explored the validity of commonly used assessment methods in comparison to gold standard hyperinsulinemic hyperglycemic clamp technique in CKD patients. An important consequence of insulin resistance is its role in the pathogenesis of protein energy wasting, a state of metabolic derangement characterized by loss of somatic and visceral protein stores not entirely accounted for by inadequate nutrient intake. In the general population, insulin resistance has been associated with accelerated protein catabolism. Among end-stage renal disease (ESRD) patients, enhanced muscle protein breakdown has been observed in patients with Type II diabetes compared to ESRD patients without diabetes. In the absence of diabetes mellitus (DM) or severe obesity, insulin resistance is detectable in dialysis patients and strongly associated with increased muscle protein breakdown, primarily mediated by the ubiquitin-proteasome pathway. Recent epidemiological data indicate a survival advantage and better nutritional status in insulin-free Type II DM patients treated with insulin sensitizer thiazolidinediones. Given the high prevalence of protein energy wasting in ESRD and its unequivocal association with adverse clinical outcomes, insulin resistance may represent an important modifiable target for intervention in the ESRD population.

Spontaneous T-cell responses against peptides derived from the Taxol resistance-associated gene-3 (TRAG-3) protein in cancer patients

DEFF Research Database (Denmark)

Meier, Anders; Hadrup, Sine Reker; Svane, Inge Marie

2005-01-01

for immunotherapy of cancer. To identify HLA-A* 02.01 - restricted epitopes from TRAG-3, we screened cancer patients for spontaneous cytotoxic T-cell responses against TRAG-3 - derived peptides. The TRAG-3 protein sequence was screened for 9mer and 10mer peptides possessing HLA-A* 02.01 - binding motifs. Of 12......Expression of the cancer-testis antigen Taxol resistance - associated gene-3 (TRAG-3) protein is associated with acquired paclitaxel ( Taxol) resistance, and is expressed in various cancer types; e. g., breast cancer, leukemia, and melanoma. Thus, TRAG-3 represents an attractive target...... potential binders, 9 peptides were indeed capable of binding to the HLA-A* 02.01 molecule, with binding affinities ranging from strong to weak binders. Subsequently, lymphocytes from cancer patients ( 9 breast cancer patients, 12 melanoma patients, and 13 patients with hematopoietic malignancies) were...

NMR studies of a new family of DNA binding proteins: the THAP proteins

International Nuclear Information System (INIS)

Gervais, Virginie; Campagne, Sébastien; Durand, Jade; Muller, Isabelle; Milon, Alain

2013-01-01

The THAP (THanatos-Associated Protein) domain is an evolutionary conserved C2CH zinc-coordinating domain shared with a large family of cellular factors (THAP proteins). Many members of the THAP family act as transcription factors that control cell proliferation, cell cycle progression, angiogenesis, apoptosis and epigenetic gene silencing. They recognize specific DNA sequences in the promoters of target genes and subsequently recruit effector proteins. Recent structural and functional studies have allowed getting better insight into the nuclear and cellular functions of some THAP members and the molecular mechanisms by which they recognize DNA. The present article reviews recent advances in the knowledge of the THAP domains structures and their interaction with DNA, with a particular focus on NMR. It provides the solution structure of the THAP domain of THAP11, a recently characterized human THAP protein with important functions in transcription and cell growth in colon cancer.

NMR studies of a new family of DNA binding proteins: the THAP proteins

Energy Technology Data Exchange (ETDEWEB)

Gervais, Virginie, E-mail: virginie.gervais@ipbs.fr [IPBS (Institut de Pharmacologie et de Biologie Structurale), CNRS (France); Campagne, Sebastien [ETH Zurich (Switzerland); Durand, Jade; Muller, Isabelle; Milon, Alain, E-mail: alain.milon@ipbs.fr [IPBS (Institut de Pharmacologie et de Biologie Structurale), CNRS (France)

2013-05-15

The THAP (THanatos-Associated Protein) domain is an evolutionary conserved C2CH zinc-coordinating domain shared with a large family of cellular factors (THAP proteins). Many members of the THAP family act as transcription factors that control cell proliferation, cell cycle progression, angiogenesis, apoptosis and epigenetic gene silencing. They recognize specific DNA sequences in the promoters of target genes and subsequently recruit effector proteins. Recent structural and functional studies have allowed getting better insight into the nuclear and cellular functions of some THAP members and the molecular mechanisms by which they recognize DNA. The present article reviews recent advances in the knowledge of the THAP domains structures and their interaction with DNA, with a particular focus on NMR. It provides the solution structure of the THAP domain of THAP11, a recently characterized human THAP protein with important functions in transcription and cell growth in colon cancer.

Ursodeoxycholic acid pretreatment reduces oral bioavailability of the multiple drug resistance-associated protein 2 substrate baicalin in rats.

Science.gov (United States)

Wu, Tao; Li, Xi-Ping; Xu, Yan-Jiao; Du, Guang; Liu, Dong

2013-11-01

Baicalin is a major bioactive component of Scutellaria baicalensis and a substrate of multiple drug resistance-associated protein 2. Expression of multiple drug resistance-associated protein 2 is regulated by NF-E2-related factor 2. The aim of this study was to explore whether ursodeoxycholic acid, an NF-E2-related factor 2 activator, could influence the oral bioavailability of baicalin. A single dose of baicalin (200 mg/kg) was given orally to rats pretreated with ursodeoxycholic acid (75 mg/kg and 150 mg/kg, per day, intragastrically) or normal saline (per day, intragastrically) for six consecutive days. The plasma concentration of baicalin was measured with the HPLC method. The result indicated that the oral bioavailability of baicalin was significantly and dose-dependently reduced in rats pretreated with ursodeoxycholic acid. Compared with control rats, the mean area under concentration-time curve of baicalin was reduced from 13.25 ± 0.24 mg/L h to 7.62 ± 0.15 mg/L h and 4.97 ± 0.21 mg/L h, and the C(max) value was decreased from 1.31 ± 0.03 mg/L to 0.62 ± 0.05 mg/L and 0.36 ± 0.04 mg/L in rats pretreated with ursodeoxycholic acid at doses of 75 mg/kg and 150 mg/kg, respectively, for six consecutive days. Hence, ursodeoxycholic acid treatment reduced the oral bioavailability of baicalin in rats, probably due to the enhanced efflux of baicalin from the intestine and liver by multiple drug resistance-associated protein 2. Georg Thieme Verlag KG Stuttgart · New York.

Genome-wide identification and characterization of stress-associated protein (SAP gene family encoding A20/AN1 zinc-finger proteins in Medicago truncatula

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Zhou Yong

2018-01-01

Full Text Available Stress associated proteins (SAPs play important roles in developmental processes, responses to various stresses and hormone stimulation in plants. However, little is known about the SAP gene family in Medicago truncatula. In this study, a total of 17 MtSAP genes encoding A20/AN1 zinc-finger proteins were characterized. Out of these 17 genes, 15 were distributed over all 8 chromosomes at different densities, and two segmental duplication events were detected. The phylogenetic analysis of these proteins and their orthologs from Arabidopsis and rice suggested that they could be classified into five out of the seven groups of SAP family genes, with genes in the same group showing similar structures and conserved domains. The cis-elements of the MtSAP promoters were studied, and many cis-elements related to stress and plant hormone responses were identified. We also investigated the stress-responsive expression patterns of the MtSAP genes under various stresses, including drought, exposure to NaCl and cold. The qRT-PCR results showed that numerous MtSAP genes exhibited transcriptional responses to multiple abiotic stresses. These results lay the foundation for further functional characterization of SAP genes. To the best of our knowledge, this is the first report of a genome-wide analysis of the SAP gene family in M. truncatula.

Heat shock protein 27 phosphorylation state is associated with cancer progression

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Maria eKatsogiannou

2014-10-01

Full Text Available Understanding the mechanisms that control stress-induced survival is critical to explain how tumors frequently resist to treatment and to improve current anti-cancer therapies. Cancer cells are able to cope with stress and escape drug toxicity by regulating heat shock proteins (Hsps expression and function. Hsp27 (HSPB1, a member of the small Hsp family, represents one of the key players of many signaling pathways contributing to tumorigenicity, treatment resistance and apoptosis inhibition. Hsp27 is overexpressed in many types of cancer and its functions are regulated by post-translational modifications, such as phosphorylation. Protein phosphorylation is the most widespread signaling mechanism in eukaryotic cells, and it is involved in all fundamental cellular processes. Aberrant phosphorylation of Hsp27 has been associated with several diseases such as cancer but the molecular mechanisms by which it is implicated in cancer development and progression remain undefined. This review focuses on the role of phosphorylation in Hsp27 functions in cancer cells and its potential usefulness as therapeutic target in cancer.

Functional analysis of P-glycoprotein and multidrug resistance associated protein related multidrug resistance in AML-blasts.

Science.gov (United States)

Brügger, D; Herbart, H; Gekeler, V; Seitz, G; Liu, C; Klingebiel, T; Orlikowsky, T; Einsele, H; Denzlinger, C; Bader, P; Niethammer, D; Beck, J F

1999-05-01

Despite the high effectiveness of various P-glycoprotein (P-gp) modulating substances in vitro their clinical value e.g. for combination treatment of acute myelogenous leukemias (AML) remains still unclear. This might be explainable by recent findings that other factors than P-gp (e.g. the multidrug resistance associated protein (MRP)) may also be involved in clinical occurring drug resistance. To study P-gp and MRP mediated MDR in AML blasts from patients with relapses at the functional level we measured rhodamine 123 (RHO) efflux in combination with a P-gp specific (SDZ PSC 833) or a MRP specific (MK571) modulator, respectively. Furthermore, direct antineoplastic drug action was monitored by determination of damaged cell fraction of a blast population using flow cytometry. We generally found strongly modulated RHO efflux by SDZ PSC 833 but slight RHO-efflux modulation by MK571 in blasts from relapsed states of AML expressing MDR1 or MRP mRNA at various levels. We could not demonstrate, though, significant PSC 833 or MK571 mediated modulation of the cytotoxic effects of etoposide. The results point to the possibility that combination of etoposide and a modulator might not improve responses to chemotherapy by targeting P-gp or MRP exclusively.

Role of the MAGUK protein family in synapse formation and function.

Science.gov (United States)

Oliva, Carlos; Escobedo, Pía; Astorga, César; Molina, Claudia; Sierralta, Jimena

2012-01-01

Synaptic function is crucially dependent on the spatial organization of the presynaptic and postsynaptic apparatuses and the juxtaposition of both membrane compartments. This precise arrangement is achieved by a protein network at the submembrane region of each cell that is built around scaffold proteins. The membrane-associated guanylate kinase (MAGUK) family of proteins is a widely expressed and well-conserved group of proteins that plays an essential role in the formation and regulation of this scaffolding. Here, we review general features of this protein family, focusing on the discs large and calcium/calmodulin-dependent serine protein kinase subfamilies of MAGUKs in the formation, function, and plasticity of synapses. Copyright © 2011 Wiley Periodicals, Inc.

Cartilage acidic protein 1, a new member of the beta-propeller protein family with amyloid propensity.

Science.gov (United States)

Anjos, Liliana; Morgado, Isabel; Guerreiro, Marta; Cardoso, João C R; Melo, Eduardo P; Power, Deborah M

2017-02-01

Cartilage acidic protein1 (CRTAC1) is an extracellular matrix protein of chondrogenic tissue in humans and its presence in bacteria indicate it is of ancient origin. Structural modeling of piscine CRTAC1 reveals it belongs to the large family of beta-propeller proteins that in mammals have been associated with diseases, including amyloid diseases such as Alzheimer's. In order to characterize the structure/function evolution of this new member of the beta-propeller family we exploited the unique characteristics of piscine duplicate genes Crtac1a and Crtac1b and compared their structural and biochemical modifications with human recombinant CRTAC1. We demonstrate that CRTAC1 has a beta-propeller structure that has been conserved during evolution and easily forms high molecular weight thermo-stable aggregates. We reveal for the first time the propensity of CRTAC1 to form amyloid-like structures, and hypothesize that the aggregating property of CRTAC1 may be related to its disease-association. We further contribute to the general understating of CRTAC1's and beta-propeller family evolution and function. Proteins 2017; 85:242-255. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Dual regulatory roles of the extended N terminus for activation of the tomato MI-1.2 resistance protein

NARCIS (Netherlands)

Lukasik-Shreepaathy, E.; Slootweg, E.; Richter, H.; Goverse, A.; Cornelissen, B.J.C.; Takken, F.L.W.

2012-01-01

Plant resistance (R) proteins mediate race-specific immunity and initiate host defenses that are often accompanied by a localized cell-death response. Most R proteins belong to the nucleotide binding-leucine-rich repeat (NB-LRR) protein family, as they carry a central NB-ARC domain fused to an LRR

Alterations in glutathione levels and apoptotic regulators are associated with acquisition of arsenic trioxide resistance in multiple myeloma.

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Shannon M Matulis

Full Text Available Arsenic trioxide (ATO has been tested in relapsed/refractory multiple myeloma with limited success. In order to better understand drug mechanism and resistance pathways in myeloma we generated an ATO-resistant cell line, 8226/S-ATOR05, with an IC50 that is 2-3-fold higher than control cell lines and significantly higher than clinically achievable concentrations. Interestingly we found two parallel pathways governing resistance to ATO in 8226/S-ATOR05, and the relevance of these pathways appears to be linked to the concentration of ATO used. We found changes in the expression of Bcl-2 family proteins Bfl-1 and Noxa as well as an increase in cellular glutathione (GSH levels. At low, clinically achievable concentrations, resistance was primarily associated with an increase in expression of the anti-apoptotic protein Bfl-1 and a decrease in expression of the pro-apoptotic protein Noxa. However, as the concentration of ATO increased, elevated levels of intracellular GSH in 8226/S-ATOR05 became the primary mechanism of ATO resistance. Removal of arsenic selection resulted in a loss of the resistance phenotype, with cells becoming sensitive to high concentrations of ATO within 7 days following drug removal, indicating changes associated with high level resistance (elevated GSH are dependent upon the presence of arsenic. Conversely, not until 50 days without arsenic did cells once again become sensitive to clinically relevant doses of ATO, coinciding with a decrease in the expression of Bfl-1. In addition we found cross-resistance to melphalan and doxorubicin in 8226/S-ATOR05, suggesting ATO-resistance pathways may also be involved in resistance to other chemotherapeutic agents used in the treatment of multiple myeloma.

A storage-protein marker associated with the suppressor of Pm8 for powdery mildew resistance in wheat.

Science.gov (United States)

Ren, S X; McIntosh, R A; Sharp, P J; The, T T

1996-11-01

A suppressor of resistance to powdery mildew conferred by Pm8 showed complete association with the presence of a storage-protein marker resolved by electrophoresis on SDS-PAGE gels. This marker was identified as the product of the gliadin allele Gli-A1a. The mildewresponse phenotypes of wheats possessing the 1BL.1RS translocation were completely predictable from electrophoretograms. The suppressor, designated SuPm8, was located on chromosome 1AS. It was specific in its suppression of Pm8, and did not affect the rye-derived resistance phenotypes of wheat lines with Pm17, also located in 1RS, or of lines with Pm7.

STIMULATION OF RESISTANCE OF BEE FAMILIES DURING WINTERING

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nicolae eremia

2013-10-01

Full Text Available Honey bees use as food nectar, honey, pollen and bee bread. They collect nectar and pollen on flowers, that process in food - honey and bee bread. Food provides the bees body with energy due to carbohydrates, proteins, enzymes, lipids, vitamins, minerals. The goal of the studies was to stimulate the bees’ resistance during wintering against nesemosa disease in bee families’ survival after winter time and productivity increasing. There was established that the optimal dose of feed additive Pramix Bionorm P (symbiotic complex, in reserves supplementing of food of bee families during autumn is 150 mg of sugar syrup. There was revealed that using of the feed additive Pramix Bionorm P (symbiotic complex, in bees feeding for reserves supplementing of bees food ensures a stimulating of resistance at wintering of bees, decreases the quantity of used honey during wintering at one space between honey combs populated with bees, as well increases the productivity.

Chitinase family GH18: evolutionary insights from the genomic history of a diverse protein family

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Aronson Nathan N

2007-06-01

Full Text Available Abstract Background Chitinases (EC.3.2.1.14 hydrolyze the β-1,4-linkages in chitin, an abundant N-acetyl-β-D-glucosamine polysaccharide that is a structural component of protective biological matrices such as insect exoskeletons and fungal cell walls. The glycoside hydrolase 18 (GH18 family of chitinases is an ancient gene family widely expressed in archea, prokaryotes and eukaryotes. Mammals are not known to synthesize chitin or metabolize it as a nutrient, yet the human genome encodes eight GH18 family members. Some GH18 proteins lack an essential catalytic glutamic acid and are likely to act as lectins rather than as enzymes. This study used comparative genomic analysis to address the evolutionary history of the GH18 multiprotein family, from early eukaryotes to mammals, in an effort to understand the forces that shaped the human genome content of chitinase related proteins. Results Gene duplication and loss according to a birth-and-death model of evolution is a feature of the evolutionary history of the GH18 family. The current human family likely originated from ancient genes present at the time of the bilaterian expansion (approx. 550 mya. The family expanded in the chitinous protostomes C. elegans and D. melanogaster, declined in early deuterostomes as chitin synthesis disappeared, and expanded again in late deuterostomes with a significant increase in gene number after the avian/mammalian split. Conclusion This comprehensive genomic study of animal GH18 proteins reveals three major phylogenetic groups in the family: chitobiases, chitinases/chitolectins, and stabilin-1 interacting chitolectins. Only the chitinase/chitolectin group is associated with expansion in late deuterostomes. Finding that the human GH18 gene family is closely linked to the human major histocompatibility complex paralogon on chromosome 1, together with the recent association of GH18 chitinase activity with Th2 cell inflammation, suggests that its late expansion

A member of a new plant gene family encoding a meprin and TRAF homology (MATH) domain-containing protein is involved in restriction of long distance movement of plant viruses

Science.gov (United States)

Cosson, Patrick; Sofer, Luc; Schurdi-Levraud, Valérie

2010-01-01

Restriction of long distance movement of several potyviruses in Arabidopsis thaliana is controlled by at least three dominant restricted TEV movement (RTM) genes, named RTM1, RTM2 and RTM3 and acts as a non-conventional resistance. RTM1 encodes a protein belonging to the jacalin family and RTM2 encodes a protein which has similarities to small heat shock proteins. The recent cloning of RTM3 which encodes a protein belonging to an unknown protein family of 29 members that has a meprin and TRAF homology (MATH) domain in its N-terminal region and a coiled-coil (CC) domain at its C-terminal end is an important breakthrough for a better understanding of this resistance process. Not only the third gene involved in this resistance has been identified and has allowed revealing a new gene family in plant but the discovery that the RTM3 protein interacts directly with RTM1 strongly suggests that the RTM proteins form a multimeric complex. However, these data also highlight striking similarities of the RTM resistance with the well known R-gene mediated resistance. PMID:20930558

Expression of P-glycoprotein and multidrug resistance associated protein in Ehrlich ascites tumor cells after fractionated irradiation

DEFF Research Database (Denmark)

Nielsen, D; Maare, C; Eriksen, J

2001-01-01

PURPOSE: To characterize irradiated murine tumor cells with respect to drug resistance, drug kinetics, and ATPase activity, and to evaluate the possible role of P-glycoprotein (PGP) and murine multidrug resistance associated protein (Mrp1) in the drug-resistant phenotype of these cells. METHODS...... AND MATERIALS: Sensitive Ehrlich ascites tumor cells (EHR2) were in vitro exposed to fractionated irradiation (60 Gy). Western blot analysis was performed for determination of PGP and Mrp1, reverse transcriptase-polymerase chain reaction (RT-PCR) for determination of mdr1a + b mRNA, and semiquantitative RT......-PCR for Mrp1 mRNA. The clonogenic assay was applied to investigate sensitivity, whereas the steady-state drug accumulation of daunorubicin (DNR), 3H-vincristine (VCR), and 3H-etoposide (VP16) was measured by spectrofluorometry and scintillation counting, respectively. For determining of ATPase activity...

Prediction and analysis of three gene families related to leaf rust (Puccinia triticina) resistance in wheat (Triticum aestivum L.).

Science.gov (United States)

Peng, Fred Y; Yang, Rong-Cai

2017-06-20

The resistance to leaf rust (Lr) caused by Puccinia triticina in wheat (Triticum aestivum L.) has been well studied over the past decades with over 70 Lr genes being mapped on different chromosomes and numerous QTLs (quantitative trait loci) being detected or mapped using DNA markers. Such resistance is often divided into race-specific and race-nonspecific resistance. The race-nonspecific resistance can be further divided into resistance to most or all races of the same pathogen and resistance to multiple pathogens. At the molecular level, these three types of resistance may cover across the whole spectrum of pathogen specificities that are controlled by genes encoding different protein families in wheat. The objective of this study is to predict and analyze genes in three such families: NBS-LRR (nucleotide-binding sites and leucine-rich repeats or NLR), START (Steroidogenic Acute Regulatory protein [STaR] related lipid-transfer) and ABC (ATP-Binding Cassette) transporter. The focus of the analysis is on the patterns of relationships between these protein-coding genes within the gene families and QTLs detected for leaf rust resistance. We predicted 526 ABC, 1117 NLR and 144 START genes in the hexaploid wheat genome through a domain analysis of wheat proteome. Of the 1809 SNPs from leaf rust resistance QTLs in seedling and adult stages of wheat, 126 SNPs were found within coding regions of these genes or their neighborhood (5 Kb upstream from transcription start site [TSS] or downstream from transcription termination site [TTS] of the genes). Forty-three of these SNPs for adult resistance and 18 SNPs for seedling resistance reside within coding or neighboring regions of the ABC genes whereas 14 SNPs for adult resistance and 29 SNPs for seedling resistance reside within coding or neighboring regions of the NLR gene. Moreover, we found 17 nonsynonymous SNPs for adult resistance and five SNPs for seedling resistance in the ABC genes, and five nonsynonymous SNPs for

Coupling of UDP-glucuronosyltransferases and multidrug resistance-associated proteins is responsible for the intestinal disposition and poor bioavailability of emodin

International Nuclear Information System (INIS)

Liu, Wei; Feng, Qian; Li, Ye; Ye, Ling; Hu, Ming; Liu, Zhongqiu

2012-01-01

Emodin is a poorly bioavailable but promising plant-derived anticancer drug candidate. The low oral bioavailability of emodin is due to its extensive glucuronidation in the intestine and liver. Caco-2 cell culture model was used to investigate the interplay between UDP-glucuronosyltransferases (UGTs) and efflux transporters in the intestinal disposition of emodin. Bidirectional transport assays of emodin at different concentrations were performed in the Caco-2 monolayers with or without multidrug resistance-associated protein (MRP) and breast cancer resistance protein (BCRP) efflux transporter chemical inhibitors. The bidirectional permeability of emodin and its glucuronide in the Caco-2 monolayers was determined. Emodin was rapidly metabolized to emodin glucuronide in Caco-2 cells. LTC4, a potent inhibitor of MRP2, decreased the efflux of emodin glucuronide and also substantially increased the intracellular glucuronide level in the basolateral-to-apical (B–A) direction. MK-571, chemical inhibitor of MRP2, MRP3, and MRP4, significantly reduced the efflux of glucuronide in the apical-to-basolateral (A–B) and B–A directions in a dose-dependent manner. However, dipyridamole, a BCRP chemical inhibitor demonstrated no effect on formation and efflux of emodin glucuronide in Caco-2 cells. In conclusion, UGT is a main metabolic pathway for emodin in the intestine, and the MRP family is composed of major efflux transporters responsible for the excretion of emodin glucuronide in the intestine. The coupling of UGTs and MRP efflux transporters causes the extensive metabolism, excretion, and low bioavailability of emodin. -- Highlights: ► Glucuronidation is the main reason for the poor oral bioavailability of emodin. ► Efflux transporters are involved in the excretion of emodin glucuronide. ► The intestine is the main organ for metabolism of emodin.

Coupling of UDP-glucuronosyltransferases and multidrug resistance-associated proteins is responsible for the intestinal disposition and poor bioavailability of emodin

Energy Technology Data Exchange (ETDEWEB)

Liu, Wei; Feng, Qian; Li, Ye; Ye, Ling [Department of Pharmaceutics, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou, Guangdong (China); Hu, Ming, E-mail: mhu@uh.edu [Department of Pharmaceutics, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou, Guangdong (China); Department of Pharmacological and Pharmaceutical Sciences, College of Pharmacy, University of Houston, 1441 Moursund Street, Houston, TX 77030 (United States); Liu, Zhongqiu, E-mail: liuzq@smu.edu.cn [Department of Pharmaceutics, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou, Guangdong (China)

2012-12-15

Emodin is a poorly bioavailable but promising plant-derived anticancer drug candidate. The low oral bioavailability of emodin is due to its extensive glucuronidation in the intestine and liver. Caco-2 cell culture model was used to investigate the interplay between UDP-glucuronosyltransferases (UGTs) and efflux transporters in the intestinal disposition of emodin. Bidirectional transport assays of emodin at different concentrations were performed in the Caco-2 monolayers with or without multidrug resistance-associated protein (MRP) and breast cancer resistance protein (BCRP) efflux transporter chemical inhibitors. The bidirectional permeability of emodin and its glucuronide in the Caco-2 monolayers was determined. Emodin was rapidly metabolized to emodin glucuronide in Caco-2 cells. LTC4, a potent inhibitor of MRP2, decreased the efflux of emodin glucuronide and also substantially increased the intracellular glucuronide level in the basolateral-to-apical (B–A) direction. MK-571, chemical inhibitor of MRP2, MRP3, and MRP4, significantly reduced the efflux of glucuronide in the apical-to-basolateral (A–B) and B–A directions in a dose-dependent manner. However, dipyridamole, a BCRP chemical inhibitor demonstrated no effect on formation and efflux of emodin glucuronide in Caco-2 cells. In conclusion, UGT is a main metabolic pathway for emodin in the intestine, and the MRP family is composed of major efflux transporters responsible for the excretion of emodin glucuronide in the intestine. The coupling of UGTs and MRP efflux transporters causes the extensive metabolism, excretion, and low bioavailability of emodin. -- Highlights: ► Glucuronidation is the main reason for the poor oral bioavailability of emodin. ► Efflux transporters are involved in the excretion of emodin glucuronide. ► The intestine is the main organ for metabolism of emodin.

No association of the polymorphisms of the frizzled-related protein gene with peak bone mineral density in Chinese nuclear families

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Yue Hua

2010-01-01

Full Text Available Abstract Background The Wnt/beta-catenin signaling pathway plays an important role in skeletal development. Polymorphisms of frizzled-related protein (FRZB, an antagonist of this pathway, may generate variations in bone mineral density (BMD. In this study, we analyzed the association between FRZB genotypes and peak BMD variation in the spines and hips of two relatively large samples of Chinese female-offspring and male-offspring nuclear families. Methods We recruited 1,260 subjects from 401 female-offspring nuclear families and 1,296 subjects from 427 male-offspring nuclear families and genotyped four tagging single nucleotide polymorphisms (tagSNPs (rs6433993, rs409238, rs288324, and rs4666865 spanning the entire FRZB gene. The SNPs rs288326 and rs7775, which are associated with hip osteoarthritis, were not selected in this study because of their low minor allele frequencies (MAFs in Chinese people. The quantitative transmission disequilibrium test (QTDT was used to analyze the association between each SNP and haplotype with peak BMD in female- and male-offspring nuclear families. Results In the female-offspring nuclear families, we found no evidence of an association between either single SNPs or haplotypes and peak BMD in the spine or hip. In the male-offspring nuclear families, no within-family association was observed for either SNPs or haplotypes, although a significant total association was found between rs4666865 and spine BMD (P = 0.0299. Conclusion Our results suggest that natural variation in FRZB is not a major contributor to the observed variability in peak BMD in either Chinese females or males. Because ethnic differences in the FRZB genotypes may exist, other studies in different population are required to confirm such results.

Multidrug Resistance-Associated Protein 3 (Mrp3/Abcc3/Moat-D) Is Expressed in the SAE Squalus acanthias Shark Embryo–Derived Cell Line

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Kobayashi, Hiroshi; Parton, Angela; Czechanski, Anne; Durkin, Christopher; Kong, Chi-Chon; Barnes, David

2008-01-01

The multidrug resistance-associated protein 3 (MRP3/Mrp3) is a member of the ATP-binding cassette (ABC) protein family of membrane transporters and related proteins that act on a variety of xenobiotic and anionic molecules to transfer these substrates in an ATP-dependent manner. In recent years, useful comparative information regarding evolutionarily conserved structure and transport functions of these proteins has accrued through the use of primitive marine animals such as cartilaginous fish. Until recently, one missing tool in comparative studies with cartilaginous fish was cell culture. We have derived from the embryo of Squalus acanthias, the spiny dogfish shark, the S. acanthias embryo (SAE) mesenchymal stem cell line. This is the first continuously proliferating cell line from a cartilaginous fish. We identified expression of Mrp3 in this cell line, cloned the molecule, and examined molecular and cellular physiological aspects of the protein. Shark Mrp3 is characterized by three membrane-spanning domains and two nucleotide-binding domains. Multiple alignments with other species showed that the shark Mrp3 amino acid sequence was well conserved. The shark sequence was overall 64% identical to human MRP3, 72% identical to chicken Mrp3, and 71% identical to frog and stickleback Mrp3. Highest identity between shark and human amino acid sequence (82%) was seen in the carboxyl-terminal nucleotide-binding domain of the proteins. Cell culture experiments showed that mRNA for the protein was induced as much as 25-fold by peptide growth factors, fetal bovine serum, and lipid nutritional components, with the largest effect mediated by a combination of lipids including unsaturated and saturated fatty acids, cholesterol, and vitamin E. PMID:18284333

Multidrug resistance-associated protein 3 (Mrp3/Abcc3/Moat-D) is expressed in the SAE Squalus acanthias shark embryo-derived cell line.

Science.gov (United States)

Kobayashi, Hiroshi; Parton, Angela; Czechanski, Anne; Durkin, Christopher; Kong, Chi-Chon; Barnes, David

2007-01-01

The multidrug resistance-associated protein 3 (MRP3/Mrp3) is a member of the ATP-binding cassette (ABC) protein family of membrane transporters and related proteins that act on a variety of xenobiotic and anionic molecules to transfer these substrates in an ATP-dependent manner. In recent years, useful comparative information regarding evolutionarily conserved structure and transport functions of these proteins has accrued through the use of primitive marine animals such as cartilaginous fish. Until recently, one missing tool in comparative studies with cartilaginous fish was cell culture. We have derived from the embryo of Squalus acanthias, the spiny dogfish shark, the S. acanthias embryo (SAE) mesenchymal stem cell line. This is the first continuously proliferating cell line from a cartilaginous fish. We identified expression of Mrp3 in this cell line, cloned the molecule, and examined molecular and cellular physiological aspects of the protein. Shark Mrp3 is characterized by three membrane-spanning domains and two nucleotide-binding domains. Multiple alignments with other species showed that the shark Mrp3 amino acid sequence was well conserved. The shark sequence was overall 64% identical to human MRP3, 72% identical to chicken Mrp3, and 71% identical to frog and stickleback Mrp3. Highest identity between shark and human amino acid sequence (82%) was seen in the carboxyl-terminal nucleotide-binding domain of the proteins. Cell culture experiments showed that mRNA for the protein was induced as much as 25-fold by peptide growth factors, fetal bovine serum, and lipid nutritional components, with the largest effect mediated by a combination of lipids including unsaturated and saturated fatty acids, cholesterol, and vitamin E.

Acquired activated protein C resistance is associated with lupus anticoagulants and thrombotic events in pediatric patients with systemic lupus erythematosus.

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Male, C; Mitchell, L; Julian, J; Vegh, P; Joshua, P; Adams, M; David, M; Andrew, M E

2001-02-15

Acquired activated protein C resistance (APCR) has been hypothesized as a possible mechanism by which antiphospholipid antibodies (APLAs) cause thrombotic events (TEs). However, available evidence for an association of acquired APCR with APLAs is limited. More importantly, an association of acquired APCR with TEs has not been demonstrated. The objective of the study was to determine, in pediatric patients with systemic lupus erythematosus (SLE), whether (1) acquired APCR is associated with the presence of APLAs, (2) APCR is associated with TEs, and (3) there is an interaction between APCR and APLAs in association with TEs. A cross-sectional cohort study of 59 consecutive, nonselected children with SLE was conducted. Primary clinical outcomes were symptomatic TEs, confirmed by objective radiographic tests. Laboratory testing included lupus anticoagulants (LAs), anticardiolipin antibodies (ACLAs), APC ratio, protein S, protein C, and factor V Leiden. The results revealed that TEs occurred in 10 (17%) of 59 patients. Acquired APCR was present in 18 (31%) of 58 patients. Acquired APCR was significantly associated with the presence of LAs but not ACLAs. Acquired APCR was also significantly associated with TEs. There was significant interaction between APCR and LAs in the association with TEs. Presence of both APCR and LAs was associated with the highest risk of a TE. Protein S and protein C concentrations were not associated with the presence of APLAs, APCR, or TEs. Presence of acquired APCR is a marker identifying LA-positive patients at high risk of TEs. Acquired APCR may reflect interference of LAs with the protein C pathway that may represent a mechanism of LA-associated TEs. (Blood. 2001;97:844-849)

Downregulation of the proapoptotic protein MOAP-1 by the UBR5 ubiquitin ligase and its role in ovarian cancer resistance to cisplatin

OpenAIRE

Matsuura, K; Huang, N-J; Cocce, K; Zhang, L; Kornbluth, S

2016-01-01

Evasion of apoptosis allows many cancers to resist chemotherapy. Apoptosis is mediated by the serial activation of caspase family proteins. These proteases are often activated upon the release of cytochrome c from the mitochondria, which is promoted by the proapoptotic Bcl-2 family protein, Bax. This function of Bax is enhanced by the MOAP-1 (modulator of apoptosis protein 1) protein in response to DNA damage. Previously, we reported that MOAP-1 is targeted for ubiquitylation and degradation ...

Pu-Erh Tea Extract Induces the Degradation of FET Family Proteins Involved in the Pathogenesis of Amyotrophic Lateral Sclerosis

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Yang Yu

2014-01-01

Full Text Available FET family proteins consist of fused in sarcoma/translocated in liposarcoma (FUS/TLS, Ewing's sarcoma (EWS, and TATA-binding protein-associated factor 15 (TAF15. Mutations in the copper/zinc superoxide dismutase (SOD1, TAR DNA-binding protein 43 (TDP-43, and FET family proteins are associated with the development of amyotrophic lateral sclerosis (ALS, a fatal neurodegenerative disease. There is currently no cure for this disease and few effective treatments are available. Epidemiological studies indicate that the consumption of tea is associated with a reduced risk of developing neurodegenerative diseases. The results of this study revealed that components of a pu-erh tea extract (PTE interacted with FET family proteins but not with TDP-43 or SOD1. PTE induced the degradation of FET family proteins but had no effects on TDP-43 or SOD1. The most frequently occurring ALS-linked FUS/TLS mutant protein, R521C FUS/TLS, was also degraded in the presence of PTE. Furthermore, ammonium chloride, a lysosome inhibitor, but not lactacystin, a proteasome inhibitor, reduced the degradation of FUS/TLS protein by PTE. PTE significantly reduced the incorporation of R521C FUS/TLS into stress granules under stress conditions. These findings suggest that PTE may have beneficial health effects, including preventing the onset of FET family protein-associated neurodegenerative diseases and delaying the progression of ALS by inhibiting the cytoplasmic aggregation of FET family proteins.

Characterization of paralogous protein families in rice

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Zhu Wei

2008-02-01

Full Text Available Abstract Background High gene numbers in plant genomes reflect polyploidy and major gene duplication events. Oryza sativa, cultivated rice, is a diploid monocotyledonous species with a ~390 Mb genome that has undergone segmental duplication of a substantial portion of its genome. This, coupled with other genetic events such as tandem duplications, has resulted in a substantial number of its genes, and resulting proteins, occurring in paralogous families. Results Using a computational pipeline that utilizes Pfam and novel protein domains, we characterized paralogous families in rice and compared these with paralogous families in the model dicotyledonous diploid species, Arabidopsis thaliana. Arabidopsis, which has undergone genome duplication as well, has a substantially smaller genome (~120 Mb and gene complement compared to rice. Overall, 53% and 68% of the non-transposable element-related rice and Arabidopsis proteins could be classified into paralogous protein families, respectively. Singleton and paralogous family genes differed substantially in their likelihood of encoding a protein of known or putative function; 26% and 66% of singleton genes compared to 73% and 96% of the paralogous family genes encode a known or putative protein in rice and Arabidopsis, respectively. Furthermore, a major skew in the distribution of specific gene function was observed; a total of 17 Gene Ontology categories in both rice and Arabidopsis were statistically significant in their differential distribution between paralogous family and singleton proteins. In contrast to mammalian organisms, we found that duplicated genes in rice and Arabidopsis tend to have more alternative splice forms. Using data from Massively Parallel Signature Sequencing, we show that a significant portion of the duplicated genes in rice show divergent expression although a correlation between sequence divergence and correlation of expression could be seen in very young genes. Conclusion

Mis-spliced transcripts of nicotinic acetylcholine receptor alpha6 are associated with field evolved spinosad resistance in Plutella xylostella (L..

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Simon W Baxter

2010-01-01

Full Text Available The evolution of insecticide resistance is a global constraint to agricultural production. Spinosad is a new, low-environmental-risk insecticide that primarily targets nicotinic acetylcholine receptors (nAChR and is effective against a wide range of pest species. However, after only a few years of application, field evolved resistance emerged in the diamondback moth, Plutella xylostella, an important pest of brassica crops worldwide. Spinosad resistance in a Hawaiian population results from a single incompletely recessive and autosomal gene, and here we use AFLP linkage mapping to identify the chromosome controlling resistance in a backcross family. Recombinational mapping with more than 700 backcross progeny positioned a putative spinosad target, nAChR alpha 6 (Pxalpha6, at the resistance locus, PxSpinR. A mutation within the ninth intron splice junction of Pxalpha6 results in mis-splicing of transcripts, which produce a predicted protein truncated between the third and fourth transmembrane domains. Additional resistance-associated Pxalpha6 transcripts that excluded the mutation containing exon were detected, and these were also predicted to produce truncated proteins. Identification of the locus of resistance in this important crop pest will facilitate field monitoring of the spread of resistance and offer insights into the genetic basis of spinosad resistance in other species.

Reduction in mRNA and protein expression of a nicotinic acetylcholine receptor α8 subunit is associated with resistance to imidacloprid in the brown planthopper, Nilaparvata lugens.

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Zhang, Yixi; Wang, Xin; Yang, Baojun; Hu, Yuanyuan; Huang, Lixin; Bass, Chris; Liu, Zewen

2015-11-01

Target-site resistance is commonly caused by qualitative changes in insecticide target-receptors and few studies have implicated quantitative changes in insecticide targets in resistance. Here we show that resistance to imidacloprid in a selected strain of Nilaparvata lugens is associated with a reduction in expression levels of the nicotinic acetylcholine receptor (nAChR) subunit Nlα8. Synergism bioassays of the selected strain suggested resistance was conferred, in part, by a target-site mechanism. Sequencing of N. lugens nAChR subunit genes identified no mutations associated with resistance, however, a decrease in mRNA and protein levels of Nlα8 was observed during selection. RNA interference knockdown of Nlα8 decreased the sensitivity of N. lugens to imidacloprid, demonstrating that a decrease in Nlα8 expression is sufficient to confer resistance in vivo. Radioligand binding assays revealed that the affinity of the high-affinity imidacloprid-binding site of native nAChRs was reduced by selection, and reducing the amount of Nlα8 cRNA injected into Xenopus oocytes significantly decreased imidacloprid potency on recombinant receptors. Taken together, these results provide strong evidence that a decrease in Nlα8 levels confers resistance to imidacloprid in N. lugens, and thus provides a rare example of target-site resistance associated with a quantitative rather than qualitative change. In insects, target-site mutations often cause high resistance to insecticides, such as neonicotinoids acting on nicotinic acetylcholine receptors (nAChRs). Here we found that a quantitative change in target-protein level, decrease in mRNA and protein levels of Nlα8, contributed importantly to imidacloprid resistance in Nilaparvata lugens. This finding provides a new target-site mechanism of insecticide resistance. © 2015 International Society for Neurochemistry.

Evaluation of iTRAQ and SWATH-MS for the Quantification of Proteins Associated with Insulin Resistance in Human Duodenal Biopsy Samples.

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Sylvie Bourassa

Full Text Available Insulin resistance (IR is associated with increased production of triglyceride-rich lipoproteins of intestinal origin. In order to assess whether insulin resistance affects the proteins involved in lipid metabolism, we used two mass spectrometry based quantitative proteomics techniques to compare the intestinal proteome of 14 IR patients to that of 15 insulin sensitive (IS control patients matched for age and waist circumference. A total of 3886 proteins were identified by the iTRAQ (Isobaric Tags for Relative and Absolute Quantitation mass spectrometry approach and 2290 by the SWATH-MS strategy (Serial Window Acquisition of Theoretical Spectra. Using these two methods, 208 common proteins were identified with a confidence corresponding to FDR < 1%, and quantified with p-value < 0.05. The quantification of those 208 proteins has a Pearson correlation coefficient (r2 of 0.728 across the two techniques. Gene Ontology analyses of the differentially expressed proteins revealed that annotations related to lipid metabolic process and oxidation reduction process are overly represented in the set of under-expressed proteins in IR subjects. Furthermore, both methods quantified proteins of relevance to IR. These data also showed that SWATH-MS is a promising and compelling alternative to iTRAQ for protein quantitation of complex mixtures.

Bipolar resistive switching in different plant and animal proteins

KAUST Repository

Bag, A.; Hota, Mrinal Kanti; Mallik, Sandipan B.; Maì ti, Chinmay Kumar

2014-01-01

We report bipolar resistive switching phenomena observed in different types of plant and animal proteins. Using protein as the switching medium, resistive switching devices have been fabricated with conducting indium tin oxide (ITO) and Al as bottom and top electrodes, respectively. A clockwise bipolar resistive switching phenomenon is observed in all proteins. It is shown that the resistive switching phenomena originate from the local redox process in the protein and the ion exchange from the top electrode/protein interface.

Bipolar resistive switching in different plant and animal proteins

KAUST Repository

Bag, A.

2014-06-01

We report bipolar resistive switching phenomena observed in different types of plant and animal proteins. Using protein as the switching medium, resistive switching devices have been fabricated with conducting indium tin oxide (ITO) and Al as bottom and top electrodes, respectively. A clockwise bipolar resistive switching phenomenon is observed in all proteins. It is shown that the resistive switching phenomena originate from the local redox process in the protein and the ion exchange from the top electrode/protein interface.

Crystal Structure of a Plant Multidrug and Toxic Compound Extrusion Family Protein.

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Tanaka, Yoshiki; Iwaki, Shigehiro; Tsukazaki, Tomoya

2017-09-05

The multidrug and toxic compound extrusion (MATE) family of proteins consists of transporters responsible for multidrug resistance in prokaryotes. In plants, a number of MATE proteins were identified by recent genomic and functional studies, which imply that the proteins have substrate-specific transport functions instead of multidrug extrusion. The three-dimensional structure of eukaryotic MATE proteins, including those of plants, has not been reported, preventing a better understanding of the molecular mechanism of these proteins. Here, we describe the crystal structure of a MATE protein from the plant Camelina sativa at 2.9 Å resolution. Two sets of six transmembrane α helices, assembled pseudo-symmetrically, possess a negatively charged internal pocket with an outward-facing shape. The crystal structure provides insight into the diversity of plant MATE proteins and their substrate recognition and transport through the membrane. Copyright © 2017 Elsevier Ltd. All rights reserved.

Pentapeptide-repeat proteins that act as topoisomerase poison resistance factors have a common dimer interface

International Nuclear Information System (INIS)

Vetting, Matthew W.; Hegde, Subray S.; Zhang, Yong; Blanchard, John S.

2011-01-01

The pentapeptide repeat protein AlbG, provides self-resistance to the nonribosomally encoded hybrid polyketide-peptide termed albicidin. Analysis of the AlbG three-dimensional structure and the sequences of other pentapeptide repeat proteins that confer resistance to topiosomerase poisons suggests they have a similar dimer interface which may be critical to their interaction with topoisomerases. The protein AlbG is a self-resistance factor against albicidin, a nonribosomally encoded hybrid polyketide-peptide with antibiotic and phytotoxic properties produced by Xanthomonas albilineans. Primary-sequence analysis indicates that AlbG is a member of the pentapeptide-repeat family of proteins (PRP). The structure of AlbG from X. albilineans was determined at 2.0 Å resolution by SAD phasing using data collected from a single trimethyllead acetate derivative on a home source. AlbG folds into a right-handed quadrilateral β-helix composed of approximately eight semi-regular coils. The regularity of the β-helix is blemished by a large loop/deviation in the β-helix between coils 4 and 5. The C-terminus of the β-helix is capped by a dimerization module, yielding a dimer with a 110 Å semi-collinear β-helical axis. This method of dimer formation appears to be common to all PRP proteins that confer resistance to topoisomerase poisons and contrasts with most PRP proteins, which are typically monomeric

Artemisinin resistance in Plasmodium falciparum is associated with an altered temporal pattern of transcription

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Newton Paul N

2011-08-01

Full Text Available Abstract Background Artemisinin resistance in Plasmodium falciparum malaria has emerged in Western Cambodia. This is a major threat to global plans to control and eliminate malaria as the artemisinins are a key component of antimalarial treatment throughout the world. To identify key features associated with the delayed parasite clearance phenotype, we employed DNA microarrays to profile the physiological gene expression pattern of the resistant isolates. Results In the ring and trophozoite stages, we observed reduced expression of many basic metabolic and cellular pathways which suggests a slower growth and maturation of these parasites during the first half of the asexual intraerythrocytic developmental cycle (IDC. In the schizont stage, there is an increased expression of essentially all functionalities associated with protein metabolism which indicates the prolonged and thus increased capacity of protein synthesis during the second half of the resistant parasite IDC. This modulation of the P. falciparum intraerythrocytic transcriptome may result from differential expression of regulatory proteins such as transcription factors or chromatin remodeling associated proteins. In addition, there is a unique and uniform copy number variation pattern in the Cambodian parasites which may represent an underlying genetic background that contributes to the resistance phenotype. Conclusions The decreased metabolic activities in the ring stages are consistent with previous suggestions of higher resilience of the early developmental stages to artemisinin. Moreover, the increased capacity of protein synthesis and protein turnover in the schizont stage may contribute to artemisinin resistance by counteracting the protein damage caused by the oxidative stress and/or protein alkylation effect of this drug. This study reports the first global transcriptional survey of artemisinin resistant parasites and provides insight to the complexities of the molecular basis

The Chloroplastic Protein THF1 Interacts with the Coiled-Coil Domain of the Disease Resistance Protein N' and Regulates Light-Dependent Cell Death.

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Hamel, Louis-Philippe; Sekine, Ken-Taro; Wallon, Thérèse; Sugiwaka, Yuji; Kobayashi, Kappei; Moffett, Peter

2016-05-01

One branch of plant immunity is mediated through nucleotide-binding/Leu-rich repeat (NB-LRR) family proteins that recognize specific effectors encoded by pathogens. Members of the I2-like family constitute a well-conserved subgroup of NB-LRRs from Solanaceae possessing a coiled-coil (CC) domain at their N termini. We show here that the CC domains of several I2-like proteins are able to induce a hypersensitive response (HR), a form of programmed cell death associated with disease resistance. Using yeast two-hybrid screens, we identified the chloroplastic protein Thylakoid Formation1 (THF1) as an interacting partner for several I2-like CC domains. Co-immunoprecipitations and bimolecular fluorescence complementation assays confirmed that THF1 and I2-like CC domains interact in planta and that these interactions take place in the cytosol. Several HR-inducing I2-like CC domains have a negative effect on the accumulation of THF1, suggesting that the latter is destabilized by active CC domains. To confirm this model, we investigated N', which recognizes the coat protein of most Tobamoviruses, as a prototypical member of the I2-like family. Transient expression and gene silencing data indicated that THF1 functions as a negative regulator of cell death and that activation of full-length N' results in the destabilization of THF1. Consistent with the known function of THF1 in maintaining chloroplast homeostasis, we show that the HR induced by N' is light-dependent. Together, our results define, to our knowledge, novel molecular mechanisms linking light and chloroplasts to the induction of cell death by a subgroup of NB-LRR proteins. © 2016 American Society of Plant Biologists. All Rights Reserved.

Major vault protein/lung resistance-related protein (MVP/LRP) expression in nervous system tumors.

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Sasaki, Tsutomu; Hankins, Gerald R; Helm, Gregory A

2002-01-01

Lung resistance-related protein (LRP) was identified as the major vault protein (MVP), the main component of multimeric vault particles. It functions as a transport-associated protein that can be associated with multidrug resistance. In previous studies, expression of MVP/LRP has been documented in tumors of various types. In general, good correlations have been reported for expression of MVP/LRP and decreased sensitivity to chemotherapy and poor prognosis. MVP/LRP expression has been documented in glioblastomas, but its expression in nervous system tumors in general has not been well characterized. Immunohistochemistry using anti-human MVP/LRP antibody (LRP-56) was performed on formalin-fixed, paraffin-embedded archival tissue from 69 primary central nervous system tumors. Expression of MVP/LRP was observed in 81.2% (56/69) of primary nervous system tumors, including astrocytomas (11/13), oligodendrogliomas (1/2), oligoastrocytomas (5/5), ependymoma (1/1), meningiomas (35/45), schwannomas (2/2), and neurofibroma (1/1). Various degrees and distributions of immunoreactivity to MVP/ LRP were observed. Neither the presence nor the degree of immunoreactivity to MVP/LRP showed any correlation with either tumor grade or the presence of brain invasion.

Targeting functional motifs of a protein family

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Bhadola, Pradeep; Deo, Nivedita

2016-10-01

The structural organization of a protein family is investigated by devising a method based on the random matrix theory (RMT), which uses the physiochemical properties of the amino acid with multiple sequence alignment. A graphical method to represent protein sequences using physiochemical properties is devised that gives a fast, easy, and informative way of comparing the evolutionary distances between protein sequences. A correlation matrix associated with each property is calculated, where the noise reduction and information filtering is done using RMT involving an ensemble of Wishart matrices. The analysis of the eigenvalue statistics of the correlation matrix for the β -lactamase family shows the universal features as observed in the Gaussian orthogonal ensemble (GOE). The property-based approach captures the short- as well as the long-range correlation (approximately following GOE) between the eigenvalues, whereas the previous approach (treating amino acids as characters) gives the usual short-range correlations, while the long-range correlations are the same as that of an uncorrelated series. The distribution of the eigenvector components for the eigenvalues outside the bulk (RMT bound) deviates significantly from RMT observations and contains important information about the system. The information content of each eigenvector of the correlation matrix is quantified by introducing an entropic estimate, which shows that for the β -lactamase family the smallest eigenvectors (low eigenmodes) are highly localized as well as informative. These small eigenvectors when processed gives clusters involving positions that have well-defined biological and structural importance matching with experiments. The approach is crucial for the recognition of structural motifs as shown in β -lactamase (and other families) and selectively identifies the important positions for targets to deactivate (activate) the enzymatic actions.

ABC transporters as multidrug resistance mechanisms and the development of chemosensitizers for their reversal

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Choi Cheol-Hee

2005-10-01

Full Text Available Abstract One of the major problems related with anticancer chemotherapy is resistance against anticancer drugs. The ATP-binding cassette (ABC transporters are a family of transporter proteins that are responsible for drug resistance and a low bioavailability of drugs by pumping a variety of drugs out cells at the expense of ATP hydrolysis. One strategy for reversal of the resistance of tumor cells expressing ABC transporters is combined use of anticancer drugs with chemosensitizers. In this review, the physiological functions and structures of ABC transporters, and the development of chemosensitizers are described focusing on well-known proteins including P-glycoprotein, multidrug resistance associated protein, and breast cancer resistance protein.

The Chloroplastic Protein THF1 Interacts with the Coiled-Coil Domain of the Disease Resistance Protein N′ and Regulates Light-Dependent Cell Death1[OPEN

Science.gov (United States)

Sekine, Ken-Taro; Wallon, Thérèse; Sugiwaka, Yuji; Kobayashi, Kappei

2016-01-01

One branch of plant immunity is mediated through nucleotide-binding/Leu-rich repeat (NB-LRR) family proteins that recognize specific effectors encoded by pathogens. Members of the I2-like family constitute a well-conserved subgroup of NB-LRRs from Solanaceae possessing a coiled-coil (CC) domain at their N termini. We show here that the CC domains of several I2-like proteins are able to induce a hypersensitive response (HR), a form of programmed cell death associated with disease resistance. Using yeast two-hybrid screens, we identified the chloroplastic protein Thylakoid Formation1 (THF1) as an interacting partner for several I2-like CC domains. Co-immunoprecipitations and bimolecular fluorescence complementation assays confirmed that THF1 and I2-like CC domains interact in planta and that these interactions take place in the cytosol. Several HR-inducing I2-like CC domains have a negative effect on the accumulation of THF1, suggesting that the latter is destabilized by active CC domains. To confirm this model, we investigated N′, which recognizes the coat protein of most Tobamoviruses, as a prototypical member of the I2-like family. Transient expression and gene silencing data indicated that THF1 functions as a negative regulator of cell death and that activation of full-length N′ results in the destabilization of THF1. Consistent with the known function of THF1 in maintaining chloroplast homeostasis, we show that the HR induced by N′ is light-dependent. Together, our results define, to our knowledge, novel molecular mechanisms linking light and chloroplasts to the induction of cell death by a subgroup of NB-LRR proteins. PMID:26951433

C-reactive protein levels and treatment resistance in schizophrenia - A Danish population-based cohort study

DEFF Research Database (Denmark)

Horsdal, Henriette Thisted; Wimberley, Theresa; Benros, Michael Eriksen

2017-01-01

-time schizophrenia diagnosis and a baseline C-reactive protein measurement (a commonly available marker of systemic inflammation) from 2000 to 2012. We defined treatment resistance as the earliest observed instance of either clozapine initiation or hospital admission due to schizophrenia after having received......OBJECTIVE: Schizophrenia is associated with increased levels of inflammatory markers. However, it remains unclear whether inflammatory markers are associated with treatment-resistant schizophrenia. METHODS: We conducted a population-based follow-up study among individuals with a first...... (4.0 vs. 3.1 mg/L, p = .13) was observed among the 52 (13.3%) treatment-resistant individuals. Increased levels of C-reactive protein (above 3 mg/L) at baseline were not associated with treatment resistance (adjusted hazard ratio = 0.99, 95% confidence interval [0.56, 1.73]). CONCLUSIONS: C...

Integral UBL domain proteins: a family of proteasome interacting proteins

DEFF Research Database (Denmark)

Hartmann-Petersen, Rasmus; Gordon, Colin

2004-01-01

The family of ubiquitin-like (UBL) domain proteins (UDPs) comprises a conserved group of proteins involved in a multitude of different cellular activities. However, recent studies on UBL-domain proteins indicate that these proteins appear to share a common property in their ability to interact...

MAMP (microbe-associated molecular pattern)-induced changes in plasma membrane-associated proteins.

Science.gov (United States)

Uhlíková, Hana; Solanský, Martin; Hrdinová, Vendula; Šedo, Ondrej; Kašparovský, Tomáš; Hejátko, Jan; Lochman, Jan

2017-03-01

Plant plasma membrane associated proteins play significant roles in Microbe-Associated Molecular Pattern (MAMP) mediated defence responses including signal transduction, membrane transport or energetic metabolism. To elucidate the dynamics of proteins associated with plasma membrane in response to cryptogein, a well-known MAMP of defence reaction secreted by the oomycete Phytophthora cryptogea, 2D-Blue Native/SDS gel electrophoresis of plasma membrane fractions was employed. This approach revealed 21 up- or down-regulated protein spots of which 15 were successfully identified as proteins related to transport through plasma membrane, vesicle trafficking, and metabolic enzymes including cytosolic NADP-malic enzyme and glutamine synthetase. Observed changes in proteins were also confirmed on transcriptional level by qRT-PCR analysis. In addition, a significantly decreased accumulation of transcripts observed after employment of a mutant variant of cryptogein Leu41Phe, exhibiting a conspicuous defect in induction of resistance, sustains the contribution of identified proteins in cryptogein-triggered cellular responses. Our data provide further evidence for dynamic MAMP-induced changes in plasma membrane associated proteins. Copyright © 2016 Elsevier GmbH. All rights reserved.

Hypoxia-inducible factor-1α induces multidrug resistance protein in colon cancer

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Lv Y

2015-07-01

Full Text Available Yingqian Lv, Shan Zhao, Jinzhu Han, Likang Zheng, Zixin Yang, Li Zhao Department of Oncology, The Second Hospital, Hebei Medical University, Shijiazhuang, Hebei Province, People’s Republic of China Abstract: Multidrug resistance is the major cause of chemotherapy failure in many solid tumors, including colon cancer. Hypoxic environment is a feature for all solid tumors and is important for the development of tumor resistance to chemotherapy. Hypoxia-inducible factor (HIF-1α is the key transcription factor that mediates cellular response to hypoxia. HIF-1α has been shown to play an important role in tumor resistance; however, the mechanism is still not fully understood. Here, we found that HIF-1α and the drug resistance-associated gene multidrug resistance associated protein 1 (MRP1 were induced by treatment of colon cancer cells with the hypoxia-mimetic agent cobalt chloride. Inhibition of HIF-1α by RNA interference and dominant-negative protein can significantly reduce the induction of MRP1 by hypoxia. Bioinformatics analysis showed that a hypoxia response element is located at -378 to -373 bp upstream of the transcription start site of MRP1 gene. Luciferase reporter assay combined with mutation analysis confirmed that this element is essential for hypoxia-mediated activation of MRP gene. Furthermore, RNA interference revealed that HIF-1α is necessary for this hypoxia-driven activation of MRP1 promoter. Importantly, chromatin immunoprecipitation analysis demonstrated that HIF-1α could directly bind to this HRE site in vivo. Together, these data suggest that MRP1 is a downstream target gene of HIF-1α, which provides a potential novel mechanism for HIF-1α-mediated drug resistance in colon cancer and maybe other solid tumors as well. Keywords: hypoxia, hypoxia-inducible factor-1α, multidrug resistance associated protein, transcriptional regulation, chemotherapy tolerance

Isolation and Cloning of cDNA Fragment of Gene Encoding for Multidrug Resistance Associated Protein from M. affine.

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Utut Widyastuti Suharsono

2008-11-01

Full Text Available Isolation and Cloning of cDNA Fragment of Gene Encoding for Multidrug Resistance Associated Protein from M. affine. M. affine can grow well in acid soil with high level of soluble aluminum. One of the important proteins in the detoxifying xenobiotic stress including acid and Al stresses is a multidrug resistance associated protein (MRP encoded by mrp gene. The objective of this research is to isolate and clone the cDNA fragment of MaMrp encoding MRP from M. affine. By reverse transcription, total cDNA had been synthesized from the total RNA as template. The fragment of cDNA MaMrp had been successfully isolated by PCR by using total cDNA as template and mrp primer designed from A. thaliana, yeast, and human. This fragment was successfully inserted into pGEM-T Easy and the recombinant plasmid was successfully introduced into E. coli DH5α. Nucleotide sequence analysis showed that the lenght of MaMrp fragment is 633 bp encoding 208 amino acids. Local alignment analysis based on nucleotide of mRNA showed that MaMrp fragment is 69% identical to AtMrp1 and 63% to AtMrp from A. thaliana. Based on deduced amino acid sequence, MaMRP is 84% identical to part of AtMRP13, 77% to AtMRP12, and 73% to AtMRP1 from A. thaliana respectively. Alignment analysis with AtMRP1 showed that MaMRP fragment is located in TM1 and NBF1 domains and has a specific amino acid sequence QCKAQLQNMEEE.

Tyrosine and aurora kinase inhibitors diminish transport function of multidrug resistance-associated protein (MRP 4 and breast cancer resistance protein (BCRP

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Rhiannon N. Hardwick

2016-12-01

Full Text Available Tyrosine and aurora kinases are important effectors in signal transduction pathways that are often involved in aberrant cancer cell growth. Tyrosine (TKI and aurora (AKI kinase inhibitors are anti-cancer agents specifically designed to target such signaling pathways through TKI/AKI binding to the ATP-binding pocket of kinases thereby leading to diminished kinase activity. Some TKIs have been identified as inhibitors of ATP-binding cassette (ABC transporters such as P-glycoprotein and breast cancer resistance protein (BCRP, which are commonly upregulated in malignant cells. TKI/AKIs have been investigated as ABC transporter inhibitors in order to facilitate the accumulation of concomitantly administered chemo-therapeutics within cancer cells. However, ABC transporters are prominently expressed in the liver and other eliminating organs, and their inhibition has been linked to intracellular accumulation of drugs, altered disposition, and toxicity. The potential for TKIs/AKIs to inhibit other important hepatic efflux transporters, particularly multidrug resistance-associated proteins (MRPs, remains unknown. The aim of the current study was to compare the inhibitory potency of 20 selected TKI/AKIs against MRP4 and BCRP through the use of inverted membrane vesicle assays. Relative IC50 values were estimated by determining TKI/AKI inhibition of MRP4-mediated [3H]-dehydroepiandrosterone sulfate uptake and BCRP-mediated [3H]-estrone sulfate uptake. To provide insight to the clinical relevance of TKI/AKI inhibition of ABC efflux transporters, the ratio of the steady-state maximum total plasma concentration (Css to the IC50 for each compound was calculated with Css/IC50 ratio >0.1 deemed potentially clinically relevant. Such analysis identified several potentially clinically relevant inhibitors of MRP4: alisertib, danusertib, erlotinib, lapatinib, neratinib, nilotinib, pazopanib, sorafenib, and tozasertib. The potentially clinically relevant inhibition of

Using hierarchical clustering of secreted protein families to classify and rank candidate effectors of rust fungi.

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Diane G O Saunders

Full Text Available Rust fungi are obligate biotrophic pathogens that cause considerable damage on crop plants. Puccinia graminis f. sp. tritici, the causal agent of wheat stem rust, and Melampsora larici-populina, the poplar leaf rust pathogen, have strong deleterious impacts on wheat and poplar wood production, respectively. Filamentous pathogens such as rust fungi secrete molecules called disease effectors that act as modulators of host cell physiology and can suppress or trigger host immunity. Current knowledge on effectors from other filamentous plant pathogens can be exploited for the characterisation of effectors in the genome of recently sequenced rust fungi. We designed a comprehensive in silico analysis pipeline to identify the putative effector repertoire from the genome of two plant pathogenic rust fungi. The pipeline is based on the observation that known effector proteins from filamentous pathogens have at least one of the following properties: (i contain a secretion signal, (ii are encoded by in planta induced genes, (iii have similarity to haustorial proteins, (iv are small and cysteine rich, (v contain a known effector motif or a nuclear localization signal, (vi are encoded by genes with long intergenic regions, (vii contain internal repeats, and (viii do not contain PFAM domains, except those associated with pathogenicity. We used Markov clustering and hierarchical clustering to classify protein families of rust pathogens and rank them according to their likelihood of being effectors. Using this approach, we identified eight families of candidate effectors that we consider of high value for functional characterization. This study revealed a diverse set of candidate effectors, including families of haustorial expressed secreted proteins and small cysteine-rich proteins. This comprehensive classification of candidate effectors from these devastating rust pathogens is an initial step towards probing plant germplasm for novel resistance components.

The heat-shock protein/chaperone network and multiple stress resistance.

Science.gov (United States)

Jacob, Pierre; Hirt, Heribert; Bendahmane, Abdelhafid

2017-04-01

Crop yield has been greatly enhanced during the last century. However, most elite cultivars are adapted to temperate climates and are not well suited to more stressful conditions. In the context of climate change, stress resistance is a major concern. To overcome these difficulties, scientists may help breeders by providing genetic markers associated with stress resistance. However, multistress resistance cannot be obtained from the simple addition of single stress resistance traits. In the field, stresses are unpredictable and several may occur at once. Consequently, the use of single stress resistance traits is often inadequate. Although it has been historically linked with the heat stress response, the heat-shock protein (HSP)/chaperone network is a major component of multiple stress responses. Among the HSP/chaperone 'client proteins', many are primary metabolism enzymes and signal transduction components with essential roles for the proper functioning of a cell. HSPs/chaperones are controlled by the action of diverse heat-shock factors, which are recruited under stress conditions. In this review, we give an overview of the regulation of the HSP/chaperone network with a focus on Arabidopsis thaliana. We illustrate the role of HSPs/chaperones in regulating diverse signalling pathways and discuss several basic principles that should be considered for engineering multiple stress resistance in crops through the HSP/chaperone network. © 2016 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.

Ghrelin- and GH-induced insulin resistance: no association with retinol-binding protein-4

DEFF Research Database (Denmark)

Vestergaard, Esben Thyssen; Krag, Morten B; Poulsen, Morten M

2013-01-01

Supraphysiological levels of ghrelin and GH induce insulin resistance. Serum levels of retinol-binding protein-4 (RBP4) correlate inversely with insulin sensitivity in patients with type 2 diabetes. We aimed to determine whether ghrelin and GH affect RBP4 levels in human subjects....

Signatures of cytoplasmic proteins in the exoproteome distinguish community- and hospital-associated methicillin-resistant Staphylococcus aureus USA300 lineages

DEFF Research Database (Denmark)

Mekonnen, Solomon A.; Palma Medina, Laura M.; Glasner, Corinna

2017-01-01

Methicillin-resistant Staphylococcus aureus (MRSA) is the common name for a heterogeneous group of highly drug-resistant staphylococci. Two major MRSA classes are distinguished based on epidemiology, namely community-associated (CA) and hospital-associated (HA) MRSA. Notably, the distinction of CA......- and HA-MRSA based on molecular traits remains difficult due to the high genomic plasticity of S. aureus. Here we sought to pinpoint global distinguishing features of CA- and HA-MRSA through a comparative genome and proteome analysis of the notorious MRSA lineage USA300. We show for the first time that CA......- and HA-MRSA isolates can be distinguished by 2 distinct extracellular protein abundance clusters that are predictive not only for epidemiologic behavior, but also for their growth and survival within epithelial cells. This ‘exoproteome profiling’ also groups more distantly related HA-MRSA isolates...

Rab11-family of interacting protein 2 associates with chlamydial inclusions through its Rab-binding domain and promotes bacterial multiplication.

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Leiva, Natalia; Capmany, Anahí; Damiani, María Teresa

2013-01-01

Chlamydia trachomatis, an obligate intracellular pathogen, survives within host cells in a special compartment named 'inclusion' and takes advantage of host vesicular transport pathways for its growth and replication. Rab GTPases are key regulatory proteins of intracellular trafficking. Several Rabs, among them Rab11 and Rab14, are implicated in chlamydial development. FIP2, a member of the Rab11-Family of Interacting Proteins, presents at the C-terminus a Rab-binding domain that interacts with both Rab11 and Rab14. In this study, we determined and characterized the recruitment of endogenous and GFP-tagged FIP2 to the chlamydial inclusions. The recruitment of FIP2 is specific since other members of the Rab11-Family of Interacting Proteins do not associate with the chlamydial inclusions. The Rab-binding domain of FIP2 is essential for its association. Our results indicate that FIP2 binds to Rab11 at the chlamydial inclusion membrane through its Rab-binding domain. The presence of FIP2 at the chlamydial inclusion favours the recruitment of Rab14. Furthermore, our results show that FIP2 promotes inclusion development and bacterial replication. In agreement, the silencing of FIP2 decreases the bacterial progeny. C. trachomatis likely recruits FIP2 to hijack host intracellular trafficking to redirect vesicles full of nutrients towards the inclusion. © 2012 Blackwell Publishing Ltd.

Guanylate kinase domains of the MAGUK family scaffold proteins as specific phospho-protein-binding modules

OpenAIRE

Zhu, Jinwei; Shang, Yuan; Xia, Caihao; Wang, Wenning; Wen, Wenyu; Zhang, Mingjie

2011-01-01

Membrane-associated guanylate kinases (MAGUK) family proteins contain an inactive guanylate kinase (GK) domain, whose function has been elusive. Here, this domain is revealed as a new type of phospho-peptide-binding module, in which the GMP-binding site has evolved to accommodate phospho-serines or -threonines.

Absence of association between major vault protein (MVP) gene polymorphisms and drug resistance in Chinese Han patients with partial epilepsy.

Science.gov (United States)

Zhou, Luo; Zhang, Mengqi; Long, Hongyu; Long, Lili; Xie, Yuanyuan; Liu, Zhaoqian; Kang, Jin; Chen, Qihua; Feng, Li; Xiao, Bo

2015-11-15

Drug resistance in epilepsy is common despite many antiepileptic drugs (AEDs) available for treatment. The development of drug resistant epilepsy may be a result of multiple factors. Several previous studies reported that the major vault protein (MVP) was significantly increased in epileptogenic brain tissues resected from patients with partial-onset seizures, indicating the possible involvement of MVP in drug resistance. In this article, we aimed to identify the association between single nucleotide polymorphisms (SNPs) of MVP gene and drug resistance of partial epilepsy in a Chinese Han population. A total of 510 patients with partial-onset seizures and 206 healthy controls were recruited. Among the patients, 222 were drug resistant and 288 were responsive. The selection of tagging SNPs was based on the Hapmap database and Haploview software and the genotyping was conducted on the Sequenom MassARRAY iPLEX platform. For the selected loci rs12149746, rs9938630 and rs4788186 in the MVP gene, there was no significant difference in allele or genotype distribution between the drug resistant and responsive groups, or between all of the patients and healthy controls. Linkage disequilibrium between any two loci was detected but there was no significant difference in haplotype frequency between the drug resistant and responsive groups. Our results suggest that MVP genetic polymorphisms and haplotypes may not be associated with drug resistance of partial epilepsy in the Chinese Han population. Copyright © 2015 Elsevier B.V. All rights reserved.

Acquired resistance to cetuximab is associated with the overexpression of Ras family members and the loss of radiosensitization in head and neck cancer cells

International Nuclear Information System (INIS)

Saki, Mohammad; Toulany, Mahmoud; Rodemann, H. Peter

2013-01-01

Purpose: Cetuximab in combination with radiation therapy is used to treat patients with head and neck squamous cell carcinoma (HNSCC). In the present study, the mechanism of acquired resistance to cetuximab in HNSCC cells was investigated in vitro. Material and methods: The HNSCC cell lines UT5 and SAS and UT5 cells with acquired resistance to cetuximab (UT5R9) were used. The radiotoxicity potentials of cetuximab and inhibitors of PI3K, MAPK and farnesylation were tested using a clonogenic survival assay. Western blotting was used to evaluate protein expression. The levels of EGFR ligands were detected by ELISA. Results: Cetuximab inhibited proliferation and induced radiosensitization in UT5 cells but not in SAS cells. In comparison with UT5 cells, cetuximab-resistant SAS cells markedly overexpressed the K-Ras, H-Ras and N-Ras proteins, as detected by Western blotting. Resistance in UT5R9 cells was associated with the overexpression of the K-Ras, H-Ras and N-Ras proteins as well as an increase in the autocrine production of the EGFR ligands amphiregulin and transforming growth factor α (TGFα). UT5R9 cells were significantly more radioresistant than UT5 cells. Radioresistant UT5R9 cells were not radiosensitized by cetuximab, but knocking down H-RAS and N-RAS with siRNA and targeting Ras farnesylation using the farnesyltransferase inhibitor lonafarnib induced radiosensitization in these cells. Targeting PI3K and MEK revealed that the activation of the PI3K/Akt pathway but not the MAPK/ERK pathway is associated with radioresistance in UT5R9 cells. Conclusion: Targeting Ras and PI3K activity improves the outcome of irradiation in cetuximab-resistant HNSCC cell lines in vitro

Members of the HCMV US12 family of predicted heptaspanning membrane proteins have unique intracellular distributions, including association with the cytoplasmic virion assembly complex

International Nuclear Information System (INIS)

Das, Subhendu; Pellett, Philip E.

2007-01-01

The human cytomegalovirus (HCMV) US12 gene family is a group of 10 predicted seven-transmembrane domain proteins that have some features in common with G-protein-coupled receptors. Little is known of their patterns of expression, localization, or functional interactions. Here, we studied the intracellular localization of three US12 family members, US14, US17, and US18, with respect to various intracellular markers and the cytoplasmic virion assembly compartment (AC). The three proteins have distinct patterns of expression, which include associations with the AC. US14 is often distributed in a uniform granular manner throughout the cytoplasm, concentrating in the AC in some cells. US17 is expressed in a segmented manner, with its N-terminal domain localizing to the periphery of what we show here to be the AC and the C-terminal domain localizing to nuclei and the cytoplasm [Das, S., Skomorovska-Prokvolit, Y., Wang, F. Z., Pellett, P.E., 2006. Infection-dependent nuclear localization of US17, a member of the US12 family of human cytomegalovirus-encoded seven-transmembrane proteins. J. Virol. 80, 1191-1203]. Here, we show that the C-terminal domain is present at the center of the AC, in close association with markers of early endosomes; the N-terminal staining corresponds to an area stained by markers for the Golgi and trans-Golgi. US18 is distributed throughout the cytoplasm, concentrating in the AC at later stages of infection; it is localized more to the periphery of the AC than are US14 and US17C, in association with markers of the trans-Golgi. Although not detected in virions, their structures and localization in various zones within the AC suggest possible roles for these proteins in the process of virion maturation and egress

Fatty acid binding protein 3 (fabp3) is associated with insulin, lipids and cardiovascular phenotypes of the metabolic syndrome through epigenetic modifications in a Northern European family population.

Science.gov (United States)

Zhang, Yi; Kent, Jack W; Lee, Adam; Cerjak, Diana; Ali, Omar; Diasio, Robert; Olivier, Michael; Blangero, John; Carless, Melanie A; Kissebah, Ahmed H

2013-03-19

Fatty acid-binding proteins (FABPs) play regulatory roles at the nexus of lipid metabolism and signaling. Dyslipidemia in clinical manifestation frequently co-occurs with obesity, insulin resistance and hypertension in the Metabolic Syndrome (MetS). Animal studies have suggested FABPs play regulatory roles in expressing MetS phenotypes. In our family cohort of Northern European descent, transcript levels in peripheral white blood cells (PWBCs) of a key FABPs, FABP3, is correlated with the MetS leading components. However, evidence supporting the functions of FABPs in humans using genetic approaches has been scarce, suggesting FABPs may be under epigenetic regulation. The objective of this study was to test the hypothesis that CpG methylation status of a key regulator of lipid homeostasis, FABP3, is a quantitative trait associated with status of MetS phenotypes in humans. We used a mass-spec based quantitative method, EpiTYPER®, to profile a CpG island that extends from the promoter to the first exon of the FABP3 gene in our family-based cohort of Northern European descent (n=517). We then conducted statistical analysis of the quantitative relationship of CpG methylation and MetS measures following the variance-component association model. Heritability of each methylation and the effect of age and sex on CpG methylation were also assessed in our families. We find that methylation levels of individual CpG units and the regional average are heritable and significantly influenced by age and sex. Regional methylation was strongly associated with plasma total cholesterol (p=0.00028) and suggestively associated with LDL-cholesterol (p=0.00495). Methylation at individual units was significantly associated with insulin sensitivity, lipid particle sizing and diastolic blood pressure (pmetabolism (βWHR=-0.72; βLDL-c=-0.53) while positively correlated with plasma adiponectin (β=0.24). Further, we show that differential methylation of FABP3 affects binding activity with

Protein function prediction involved on radio-resistant bacteria

International Nuclear Information System (INIS)

Mezhoud, Karim; Mankai, Houda; Sghaier, Haitham; Barkallah, Insaf

2009-01-01

Previously, we identified 58 proteins under positive selection in ionizing-radiation-resistant bacteria (IRRB) but absent in all ionizing-radiation-sensitive bacteria (IRSB). These are good reasons to believe these 58 proteins with their interactions with other proteins (interactomes) are a part of the answer to the question as to how IRRB resist to radiation, because our knowledge of interactomes of positively selected orphan proteins in IRRB might allow us to define cellular pathways important to ionizing-radiation resistance. Using the Database of Interacting Proteins and the PSIbase, we have predicted interactions of orthologs of the 58 proteins under positive selection in IRRB but absent in all IRSB. We used integrate experimental data sets with molecular interaction networks and protein structure prediction from databases. Among these, 18 proteins with their interactomes were identified in Deinococcus radiodurans R1. DNA checkpoint and repair, kinases pathways, energetic and nucleotide metabolisms were the important biological process that found. We predicted the interactomes of 58 proteins under positive selection in IRRB. It is hoped our data will provide new clues as to the cellular pathways that are important for ionizing-radiation resistance. We have identified news proteins involved on DNA management which were not previously mentioned. It is an important input in addition to protein that studied. It does still work to deepen our study on these new proteins

The function of yeast CAP family proteins in lipid export, mating, and pathogen defense.

Science.gov (United States)

Darwiche, Rabih; El Atab, Ola; Cottier, Stéphanie; Schneiter, Roger

2018-04-01

In their natural habitat, yeast cells are constantly challenged by changing environmental conditions and a fierce competition for limiting resources. To thrive under such conditions, cells need to adapt and divide quickly, and be able to neutralize the toxic compounds secreted by their neighbors. Proteins like the pathogen-related yeast, Pry proteins, which belong to the large CAP/SCP/TAPS superfamily, may have an important role in this function. CAP proteins are conserved from yeast to man and are characterized by a unique αβα sandwich fold. They are mostly secreted glycoproteins and have been implicated in many different physiological processes including pathogen defense, virulence, venom toxicity, and sperm maturation. Yeast members of this family bind and export sterols as well as fatty acids, and they render cells resistant to eugenol, an antimicrobial compound present in clove oil. CAP family members might thus exert their various physiological functions through binding, sequestration, and neutralization of such small hydrophobic compounds. © 2017 Federation of European Biochemical Societies.

Functional studies of ssDNA binding ability of MarR family protein TcaR from Staphylococcus epidermidis.

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Yu-Ming Chang

Full Text Available The negative transcription regulator of the ica locus, TcaR, regulates proteins involved in the biosynthesis of poly-N-acetylglucosamine (PNAG. Absence of TcaR increases PNAG production and promotes biofilm formation in Staphylococci. Previously, the 3D structure of TcaR in its apo form and its complex structure with several antibiotics have been analyzed. However, the detailed mechanism of multiple antibiotic resistance regulator (MarR family proteins such as TcaR is unclear and only restricted on the binding ability of double-strand DNA (dsDNA. Here we show by electrophoretic mobility shift assay (EMSA, electron microscopy (EM, circular dichroism (CD, and Biacore analysis that TcaR can interact strongly with single-stranded DNA (ssDNA, thereby identifying a new role in MarR family proteins. Moreover, we show that TcaR preferentially binds 33-mer ssDNA over double-stranded DNA and inhibits viral ssDNA replication. In contrast, such ssDNA binding properties were not observed for other MarR family protein and TetR family protein, suggesting that the results from our studies are not an artifact due to simple charge interactions between TcaR and ssDNA. Overall, these results suggest a novel role for TcaR in regulation of DNA replication. We anticipate that the results of this work will extend our understanding of MarR family protein and broaden the development of new therapeutic strategies for Staphylococci.

Characterization of Hospital-Associated Lineages of Ampicillin-Resistant Enterococcus faecium from Clinical Cases in Dogs and Humans

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Cindy-Love eTremblay

2013-08-01

Full Text Available Ampicillin-resistant Enterococcus faecium (ARE has rapidly emerged worldwide and is one of the most important nosocomial pathogens. However, very few reports are available on ARE isolates from canine clinical cases. The objective of this study was to characterize ARE strains of canine clinical origin from a veterinary teaching hospital in Canada and to compare them with human strains. Ten ARE strains from dogs and humans were characterized by multilocus sequence typing (MLST, pulsed field gel electrophoresis (PFGE, antibiotic susceptibility and biofilm activities, presence of rep-families, CRISPR-cas and putative virulence genes. All ARE strains (n = 10 were resistant to ciprofloxacin and lincomycin. Resistances to tetracycline (n = 6, macrolides (n = 6, and to high concentrations of gentamicin, kanamycin and streptomycin (n = 5 were also observed. Canine ARE isolates were found to be susceptible to vancomycin whereas resistance to this antibiotic was observed in human strains. Ampicillin resistance was linked to PBP5 showing mutations at 25 amino acid positions. Fluoroquinolone resistance was attributable to ParC, GyrA, and GyrB mutations. Data demonstrated that all canine ARE were acm (collagen binding protein-positive and that most harbored the efaAfm gene, encoding for a cell wall adhesin. Biofilm formation was observed in two human strains but not in canine strains. Two to five rep-families were observed per strain but no CRISPR sequences were found. A total of six STs (1, 18, 65, 202, 205, and 803 were found with one belonging to a new ST (ST803. These STs were identical or closely related to human hospital-associated lineages. This report describes for the first time the characterization of canine ARE hospital-associated strains in Canada and also supports the importance of prudent antibiotic use in veterinary medicine to avoid zoonotic spread of canine ARE.

Global characterization of signalling networks associated with tamoxifen resistance in breast cancer

DEFF Research Database (Denmark)

Browne, Brigid C.; Hochgräfe, Falko; Wu, Jianmin

2013-01-01

R cells. Phosphorylation of the tyrosine kinase Yes and expression of the actin‐binding protein myristoylated alanine‐rich C‐kinase substrate (MARCKS) were increased two‐ and eightfold in TamR cells respectively, and these proteins were selected for further analysis. Knockdown of either protein in Tam......Acquired resistance to the anti‐estrogen tamoxifen remains a significant challenge in breast cancer management. In this study, we used an integrative approach to characterize global protein expression and tyrosine phosphorylation events in tamoxifen‐resistant MCF7 breast cancer cells (Tam...... was perturbed in TamR cells, together with pathways enriched for proteins associated with growth factor, cell–cell and cell matrix‐initiated signalling. Consistent with known roles for Ras/MAPK and PI3‐kinase signalling in tamoxifen resistance, tyrosine‐phosphorylated MAPK1, SHC1 and PIK3R2 were elevated in Tam...

Characterization of Soybean WRKY Gene Family and Identification of Soybean WRKY Genes that Promote Resistance to Soybean Cyst Nematode.

Science.gov (United States)

Yang, Yan; Zhou, Yuan; Chi, Yingjun; Fan, Baofang; Chen, Zhixiang

2017-12-19

WRKY proteins are a superfamily of plant transcription factors with important roles in plants. WRKY proteins have been extensively analyzed in plant species including Arabidopsis and rice. Here we report characterization of soybean WRKY gene family and their functional analysis in resistance to soybean cyst nematode (SCN), the most important soybean pathogen. Through search of the soybean genome, we identified 174 genes encoding WRKY proteins that can be classified into seven groups as established in other plants. WRKY variants including a WRKY-related protein unique to legumes have also been identified. Expression analysis reveals both diverse expression patterns in different soybean tissues and preferential expression of specific WRKY groups in certain tissues. Furthermore, a large number of soybean WRKY genes were responsive to salicylic acid. To identify soybean WRKY genes that promote soybean resistance to SCN, we first screened soybean WRKY genes for enhancing SCN resistance when over-expressed in transgenic soybean hairy roots. To confirm the results, we transformed five WRKY genes into a SCN-susceptible soybean cultivar and generated transgenic soybean lines. Transgenic soybean lines overexpressing three WRKY transgenes displayed increased resistance to SCN. Thus, WRKY genes could be explored to develop new soybean cultivars with enhanced resistance to SCN.

Downregulation of the proapoptotic protein MOAP-1 by the UBR5 ubiquitin ligase and its role in ovarian cancer resistance to cisplatin

Science.gov (United States)

Matsuura, K; Huang, N-J; Cocce, K; Zhang, L; Kornbluth, S

2017-01-01

Evasion of apoptosis allows many cancers to resist chemotherapy. Apoptosis is mediated by the serial activation of caspase family proteins. These proteases are often activated upon the release of cytochrome c from the mitochondria, which is promoted by the proapoptotic Bcl-2 family protein, Bax. This function of Bax is enhanced by the MOAP-1 (modulator of apoptosis protein 1) protein in response to DNA damage. Previously, we reported that MOAP-1 is targeted for ubiquitylation and degradation by the APC/CCdh1 ubiquitin ligase. In this study, we identify the HECT (homologous to the E6-AP carboxyl terminus) family E3 ubiquitin ligase, UBR5, as a novel ubiquitin ligase for MOAP-1. We demonstrate that UBR5 interacts physically with MOAP-1, ubiquitylates MOAP-1 in vitro and inhibits MOAP-1 stability in cultured cells. In addition, we show that Dyrk2 kinase, a reported UBR5 interactor, cooperates with UBR5 in mediating MOAP-1 ubiquitylation. Importantly, we found that cisplatin-resistant ovarian cancer cell lines exhibit lower levels of MOAP-1 accumulation than their sensitive counterparts upon cisplatin treatment, consistent with the previously reported role of MOAP-1 in modulating cisplatin-induced apoptosis. Accordingly, UBR5 knockdown increased MOAP-1 expression, enhanced Bax activation and sensitized otherwise resistant cells to cisplatin-induced apoptosis. Furthermore, UBR5 expression was higher in ovarian cancers from cisplatin-resistant patients than from cisplatin-responsive patients. These results show that UBR5 downregulates proapoptotic MOAP-1 and suggest that UBR5 can confer cisplatin resistance in ovarian cancer. Thus UBR5 may be an attractive therapeutic target for ovarian cancer treatment. PMID:27721409

The heat shock protein/chaperone network and multiple stress resistance

KAUST Repository

Jacob, Pierre; Hirt, Heribert; Bendahmane, Abdelhafid

2016-01-01

Crop yield has been greatly enhanced during the last century. However, most elite cultivars are adapted to temperate climates and are not well suited to more stressful conditions. In the context of climate change, stress resistance is a major concern. To overcome these difficulties, scientists may help breeders by providing genetic markers associated with stress resistance. However, multi-stress resistance cannot be obtained from the simple addition of single stress resistance traits. In the field, stresses are unpredictable and several may occur at once. Consequently, the use of single stress resistance traits is often inadequate. Although it has been historically linked with the heat stress response, the heat shock protein (HSP)/chaperone network is a major component of multiple stress responses. Among the HSP/chaperone

The heat shock protein/chaperone network and multiple stress resistance

KAUST Repository

Jacob, Pierre

2016-11-15

Crop yield has been greatly enhanced during the last century. However, most elite cultivars are adapted to temperate climates and are not well suited to more stressful conditions. In the context of climate change, stress resistance is a major concern. To overcome these difficulties, scientists may help breeders by providing genetic markers associated with stress resistance. However, multi-stress resistance cannot be obtained from the simple addition of single stress resistance traits. In the field, stresses are unpredictable and several may occur at once. Consequently, the use of single stress resistance traits is often inadequate. Although it has been historically linked with the heat stress response, the heat shock protein (HSP)/chaperone network is a major component of multiple stress responses. Among the HSP/chaperone

Structure and function of the contactin-associated protein family in myelinated axons and their relationship with nerve diseases

Institute of Scientific and Technical Information of China (English)

Yan Zou; De-en Xu; Wei-feng Zhang; Hai-ying Liu; Xia Li; Xing Zhang; Xiao-fang Ma; Yang Sun; Shi-yi Jiang; Quan-hong Ma

2017-01-01

The contactin-associated protein (Caspr) family participates in nerve excitation and conduction, and neurotransmitter release in myelinated axons. We analyzed the structures and functions of the Caspr family–CNTNAP1 (Caspr1), CNTNAP2 (Caspr2), CNTNAP3 (Caspr3), CNTNAP4 (Caspr4) and CNTNAP5 (Caspr5), Caspr1–5 is not only involved in the formation of myelinated axons, but also participates in maintaining the stability of adjacent connections. Caspr1 participates in the formation, differentiation, and proliferation of neurons and astrocytes, and in motor control and cognitive function. We also analyzed the relationship between the Caspr family and neurodegenerative diseases, multiple sclerosis, and autoimmune encephalitis. However, the effects of Caspr on disease course and prognosis remain poorly understood. The effects of Caspr on disease diagnosis and treatment need further investigation.

Molecular mechanisms of reduced glutathione transport: role of the MRP/CFTR/ABCC and OATP/SLC21A families of membrane proteins

International Nuclear Information System (INIS)

Ballatori, Nazzareno; Hammond, Christine L.; Cunningham, Jennifer B.; Krance, Suzanne M.; Marchan, Rosemarie

2005-01-01

The initial step in reduced glutathione (GSH) turnover in all mammalian cells is its transport across the plasma membrane into the extracellular space; however, the mechanisms of GSH transport are not clearly defined. GSH export is required for the delivery of its constituent amino acids to other tissues, detoxification of drugs, metals, and other reactive compounds of both endogenous and exogenous origin, protection against oxidant stress, and secretion of hepatic bile. Recent studies indicate that some members of the multidrug resistance-associated protein (MRP/CFTR or ABCC) family of ATP-binding cassette (ABC) proteins, as well as some members of the organic anion transporting polypeptide (OATP or SLC21A) family of transporters contribute to this process. In particular, five of the 12 members of the MRP/CFTR family appear to mediate GSH export from cells namely, MRP1, MRP2, MRP4, MRP5, and CFTR. Additionally, two members of the OATP family, rat Oatp1 and Oatp2, have been identified as GSH transporters. For the Oatp1 transporter, efflux of GSH may provide the driving force for the uptake of extracellular substrates. In humans, OATP-B and OATP8 do not appear to transport GSH; however, other members of this family have yet to be characterized in regards to GSH transport. In yeast, the ABC proteins Ycf1p and Bpt1p transport GSH from the cytosol into the vacuole, whereas Hgt1p mediates GSH uptake across the plasma membrane. Because transport is a key step in GSH homeostasis and is intimately linked to its biological functions, GSH export proteins are likely to modulate essential cellular functions

Cross-Resistance between Cry1 Proteins in Fall Armyworm (Spodoptera frugiperda) May Affect the Durability of Current Pyramided Bt Maize Hybrids in Brazil.

Science.gov (United States)

Bernardi, Daniel; Salmeron, Eloisa; Horikoshi, Renato Jun; Bernardi, Oderlei; Dourado, Patrick Marques; Carvalho, Renato Assis; Martinelli, Samuel; Head, Graham P; Omoto, Celso

2015-01-01

Genetically modified plants expressing insecticidal proteins from Bacillus thuringiensis (Bt) offer valuable options for managing insect pests with considerable environmental and economic benefits. Despite the benefits provided by Bt crops, the continuous expression of these insecticidal proteins imposes strong selection for resistance in target pest populations. Bt maize (Zea mays) hybrids have been successful in controlling fall armyworm (Spodoptera frugiperda), the main maize pest in Brazil since 2008; however, field-evolved resistance to the protein Cry1F has recently been reported. Therefore it is important to assess the possibility of cross-resistance between Cry1F and other Cry proteins expressed in Bt maize hybrids. In this study, an F2 screen followed by subsequent selection on MON 89034 maize was used to select an S. frugiperda strain (RR) able to survive on the Bt maize event MON 89034, which expresses the Cry1A.105 and Cry2Ab2 proteins. Field-collected insects from maize expressing the Cry1F protein (event TC1507) represented most of the positive (resistance allele-containing) (iso)families found. The RR strain showed high levels of resistance to Cry1F, which apparently also conferred high levels of cross resistance to Cry1A.105 and Cry1Ab, but had only low-level (10-fold) resistance to Cry2Ab2. Life history studies to investigate fitness costs associated with the resistance in RR strain revealed only small reductions in reproductive rate when compared to susceptible and heterozygous strains, but the RR strain produced 32.2% and 28.4% fewer females from each female relative to the SS and RS (pooled) strains, respectively. Consistent with the lack of significant resistance to Cry2Ab2, MON 89034 maize in combination with appropriate management practices continues to provide effective control of S. frugiperda in Brazil. Nevertheless, the occurrence of Cry1F resistance in S. frugiperda across Brazil, and the cross-resistance to Cry1Ab and Cry1A.105

Multiple drug resistance protein (MDR-1, multidrug resistance-related protein (MRP and lung resistance protein (LRP gene expression in childhood acute lymphoblastic leukemia

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Elvis Terci Valera

Full Text Available CONTEXT: Despite the advances in the cure rate for acute lymphoblastic leukemia, approximately 25% of affected children suffer relapses. Expression of genes for the multiple drug resistance protein (MDR-1, multidrug resistance-related protein (MRP, and lung resistance protein (LRP may confer the phenotype of resistance to the treatment of neoplasias. OBJECTIVE: To analyze the expression of the MDR-1, MRP and LRP genes in children with a diagnosis of acute lymphoblastic leukemia via the semiquantitative reverse transcription polymerase chain reaction (RT-PCR, and to determine the correlation between expression and event-free survival and clinical and laboratory variables. DESIGN: A retrospective clinical study. SETTING: Laboratory of Pediatric Oncology, Department of Pediatrics, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Brazil. METHODS: Bone marrow aspirates from 30 children with a diagnosis of acute lymphoblastic leukemia were assessed for the expression of messenger RNA for the MDR-1, MRP and LRP genes by semi-quantitative RT-PCR. RESULTS: In the three groups studied, only the increased expression of LRP was related to worsened event-free survival (p = 0.005. The presence of the common acute lymphoblastic leukemia antigen (CALLA was correlated with increased LRP expression (p = 0.009 and increased risk of relapse or death (p = 0.05. The relative risk of relapse or death was six times higher among children with high LRP expression upon diagnosis (p = 0.05, as confirmed by multivariate analysis of the three genes studied (p = 0.035. DISCUSSION: Cell resistance to drugs is a determinant of the response to chemotherapy and its detection via RT-PCR may be of clinical importance. CONCLUSIONS: Evaluation of the expression of genes for resistance to antineoplastic drugs in childhood acute lymphoblastic leukemia upon diagnosis, and particularly the expression of the LRP gene, may be of clinical relevance, and should be the

Amyotrophic lateral sclerosis mutant vesicle-associated membrane protein-associated protein-B transgenic mice develop TAR-DNA-binding protein-43 pathology.

LENUS (Irish Health Repository)

Tudor, E L

2010-05-19

Cytoplasmic ubiquitin-positive inclusions containing TAR-DNA-binding protein-43 (TDP-43) within motor neurons are the hallmark pathology of sporadic amyotrophic lateral sclerosis (ALS). TDP-43 is a nuclear protein and the mechanisms by which it becomes mislocalized and aggregated in ALS are not properly understood. A mutation in the vesicle-associated membrane protein-associated protein-B (VAPB) involving a proline to serine substitution at position 56 (VAPBP56S) is the cause of familial ALS type-8. To gain insight into the molecular mechanisms by which VAPBP56S induces disease, we created transgenic mice that express either wild-type VAPB (VAPBwt) or VAPBP56S in the nervous system. Analyses of both sets of mice revealed no overt motor phenotype nor alterations in survival. However, VAPBP56S but not VAPBwt transgenic mice develop cytoplasmic TDP-43 accumulations within spinal cord motor neurons that were first detected at 18 months of age. Our results suggest a link between abnormal VAPBP56S function and TDP-43 mislocalization.

The intrinsically disordered structural platform of the plant defence hub protein RPM1-interacting protein 4 provides insights into its mode of action in the host-pathogen interface and evolution of the nitrate-induced domain protein family.

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Sun, Xiaolin; Greenwood, David R; Templeton, Matthew D; Libich, David S; McGhie, Tony K; Xue, Bin; Yoon, Minsoo; Cui, Wei; Kirk, Christopher A; Jones, William T; Uversky, Vladimir N; Rikkerink, Erik H A

2014-09-01

Arabidopsis thaliana (At) RPM1-interacting protein 4 (RIN4), targeted by many defence-suppressing bacterial type III effectors and monitored by several resistance proteins, regulates plant immune responses to pathogen-associated molecular patterns and type III effectors. Little is known about the overall protein structure of AtRIN4, especially in its unbound form, and the relevance of structure to its diverse biological functions. AtRIN4 contains two nitrate-induced (NOI) domains and is a member of the NOI family. Using experimental and bioinformatic approaches, we demonstrate that the unbound AtRIN4 is intrinsically disordered under physiological conditions. The intrinsically disordered polypeptide chain of AtRIN4 is interspersed with molecular recognition features (MoRFs) and anchor-identified long-binding regions, potentially allowing it to undergo disorder-to-order transitions upon binding to partner(s). A poly-l-proline II structure, often responsible for protein recognition, is also identified in AtRIN4. By performing bioinformatics analyses on RIN4 homologues from different plant species and the NOI proteins from Arabidopsis, we infer the conservation of intrinsic disorder, MoRFs and long-binding regions of AtRIN4 in other plant species and the NOI family. Intrinsic disorder and MoRFs could provide RIN4 proteins with the binding promiscuity and plasticity required to act as hubs in a pivotal position within plant defence signalling cascades. © 2014 FEBS.

Characterization of a Novel Endoplasmic Reticulum Protein Involved in Tubercidin Resistance in Leishmania major.

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Juliana Ide Aoki

2016-09-01

Full Text Available Tubercidin (TUB is a toxic adenosine analog with potential antiparasitic activity against Leishmania, with mechanism of action and resistance that are not completely understood. For understanding the mechanisms of action and identifying the potential metabolic pathways affected by this drug, we employed in this study an overexpression/selection approach using TUB for the identification of potential targets, as well as, drug resistance genes in L. major. Although, TUB is toxic to the mammalian host, these findings can provide evidences for a rational drug design based on purine pathway against leishmaniasis.After transfection of a cosmid genomic library into L. major Friedlin (LmjF parasites and application of the overexpression/selection method, we identified two cosmids (cosTUB1 and cosTU2 containing two different loci capable of conferring significant levels of TUB resistance. In the cosTUB1 contained a gene encoding NUPM1-like protein, which has been previously described as associated with TUB resistance in L. amazonensis. In the cosTUB2 we identified and characterized a gene encoding a 63 kDa protein that we denoted as tubercidin-resistance protein (TRP. Functional analysis revealed that the transfectants were less susceptible to TUB than LmjF parasites or those transfected with the control vector. In addition, the trp mRNA and protein levels in cosTUB2 transfectants were higher than LmjF. TRP immunolocalization revealed that it was co-localized to the endoplasmic reticulum (ER, a cellular compartment with many functions. In silico predictions indicated that TRP contains only a hypothetical transmembrane domain. Thus, it is likely that TRP is a lumen protein involved in multidrug efflux transport that may be involved in the purine metabolic pathway.This study demonstrated for the first time that TRP is associated with TUB resistance in Leishmania. The next challenge is to determine how TRP mediates TUB resistance and whether purine

Characterization of a Novel Endoplasmic Reticulum Protein Involved in Tubercidin Resistance in Leishmania major.

Science.gov (United States)

Aoki, Juliana Ide; Coelho, Adriano Cappellazzo; Muxel, Sandra Marcia; Zampieri, Ricardo Andrade; Sanchez, Eduardo Milton Ramos; Nerland, Audun Helge; Floeter-Winter, Lucile Maria; Cotrim, Paulo Cesar

2016-09-01

Tubercidin (TUB) is a toxic adenosine analog with potential antiparasitic activity against Leishmania, with mechanism of action and resistance that are not completely understood. For understanding the mechanisms of action and identifying the potential metabolic pathways affected by this drug, we employed in this study an overexpression/selection approach using TUB for the identification of potential targets, as well as, drug resistance genes in L. major. Although, TUB is toxic to the mammalian host, these findings can provide evidences for a rational drug design based on purine pathway against leishmaniasis. After transfection of a cosmid genomic library into L. major Friedlin (LmjF) parasites and application of the overexpression/selection method, we identified two cosmids (cosTUB1 and cosTU2) containing two different loci capable of conferring significant levels of TUB resistance. In the cosTUB1 contained a gene encoding NUPM1-like protein, which has been previously described as associated with TUB resistance in L. amazonensis. In the cosTUB2 we identified and characterized a gene encoding a 63 kDa protein that we denoted as tubercidin-resistance protein (TRP). Functional analysis revealed that the transfectants were less susceptible to TUB than LmjF parasites or those transfected with the control vector. In addition, the trp mRNA and protein levels in cosTUB2 transfectants were higher than LmjF. TRP immunolocalization revealed that it was co-localized to the endoplasmic reticulum (ER), a cellular compartment with many functions. In silico predictions indicated that TRP contains only a hypothetical transmembrane domain. Thus, it is likely that TRP is a lumen protein involved in multidrug efflux transport that may be involved in the purine metabolic pathway. This study demonstrated for the first time that TRP is associated with TUB resistance in Leishmania. The next challenge is to determine how TRP mediates TUB resistance and whether purine metabolism is affected

Evolutionary plasticity of plasma membrane interaction in DREPP family proteins.

Science.gov (United States)

Vosolsobě, Stanislav; Petrášek, Jan; Schwarzerová, Kateřina

2017-05-01

The plant-specific DREPP protein family comprises proteins that were shown to regulate the actin and microtubular cytoskeleton in a calcium-dependent manner. Our phylogenetic analysis showed that DREPPs first appeared in ferns and that DREPPs have a rapid and plastic evolutionary history in plants. Arabidopsis DREPP paralogues called AtMDP25/PCaP1 and AtMAP18/PCaP2 are N-myristoylated, which has been reported as a key factor in plasma membrane localization. Here we show that N-myristoylation is neither conserved nor ancestral for the DREPP family. Instead, by using confocal microscopy and a new method for quantitative evaluation of protein membrane localization, we show that DREPPs rely on two mechanisms ensuring their plasma membrane localization. These include N-myristoylation and electrostatic interaction of a polybasic amino acid cluster. We propose that various plasma membrane association mechanisms resulting from the evolutionary plasticity of DREPPs are important for refining plasma membrane interaction of these signalling proteins under various conditions and in various cells. Copyright © 2017 Elsevier B.V. All rights reserved.

Insulin-resistance and metabolic syndrome are related to executive function in women in a large family-based study.

Science.gov (United States)

Schuur, M; Henneman, P; van Swieten, J C; Zillikens, M C; de Koning, I; Janssens, A C J W; Witteman, J C M; Aulchenko, Y S; Frants, R R; Oostra, B A; van Dijk, K Willems; van Duijn, C M

2010-08-01

While type 2 diabetes is well-known to be associated with poorer cognitive performance, few studies have reported on the association of metabolic syndrome (MetS) and contributing factors, such as insulin-resistance (HOMA-IR), low adiponectin-, and high C-reactive protein (CRP)-levels. We studied whether these factors are related to cognitive function and which of the MetS components are independently associated. The study was embedded in an ongoing family-based cohort study in a Dutch population. All participants underwent physical examinations, biomedical measurements, and neuropsychological testing. Linear regression models were used to determine the association between MetS, HOMA-IR, adiponectin levels, CRP, and cognitive test scores. Cross-sectional analyses were performed in 1,898 subjects (mean age 48 years, 43% men). People with MetS had significantly higher HOMA-IR scores, lower adiponectin levels, and higher CRP levels. MetS and high HOMA-IR were associated with poorer executive function in women (P = 0.03 and P = 0.009). MetS and HOMA-IR are associated with poorer executive function in women.

Overexpression of Rice Wall-Associated Kinase 25 (OsWAK25) Alters Resistance to Bacterial and Fungal Pathogens

Science.gov (United States)

Harkenrider, Mitch; Sharma, Rita; De Vleesschauwer, David; Tsao, Li; Zhang, Xuting; Chern, Mawsheng; Canlas, Patrick; Zuo, Shimin; Ronald, Pamela C.

2016-01-01

Wall-associated kinases comprise a sub-family of receptor-like kinases that function in plant growth and stress responses. Previous studies have shown that the rice wall-associated kinase, OsWAK25, interacts with a diverse set of proteins associated with both biotic and abiotic stress responses. Here, we show that wounding and BTH treatments induce OsWAK25 transcript expression in rice. We generated OsWAK25 overexpression lines and show that these lines exhibit a lesion mimic phenotype and enhanced expression of rice NH1 (NPR1 homolog 1), OsPAL2, PBZ1 and PR10. Furthermore, these lines show resistance to the hemibiotrophic pathogens, Xanthomonas oryzae pv. oryzae (Xoo) and Magnaporthe oryzae, yet display increased susceptibility to necrotrophic fungal pathogens, Rhizoctonia solani and Cochliobolus miyabeanus. PMID:26795719

Specific chlamydial inclusion membrane proteins associate with active Src family kinases in microdomains that interact with the host microtubule network.

Science.gov (United States)

Mital, Jeffrey; Miller, Natalie J; Fischer, Elizabeth R; Hackstadt, Ted

2010-09-01

Chlamydiae are Gram-negative obligate intracellular bacteria that cause diseases with significant medical and economic impact. Chlamydia trachomatis replicates within a vacuole termed an inclusion, which is extensively modified by the insertion of a number of bacterial effector proteins known as inclusion membrane proteins (Incs). Once modified, the inclusion is trafficked in a dynein-dependent manner to the microtubule-organizing centre (MTOC), where it associates with host centrosomes. Here we describe a novel structure on the inclusion membrane comprised of both host and bacterial proteins. Members of the Src family of kinases are recruited to the chlamydial inclusion in an active form. These kinases display a distinct, localized punctate microdomain-like staining pattern on the inclusion membrane that colocalizes with four chlamydial inclusion membrane proteins (Incs) and is enriched in cholesterol. Biochemical studies show that at least two of these Incs stably interact with one another. Furthermore, host centrosomes associate with these microdomain proteins in C. trachomatis-infected cells and in uninfected cells exogenously expressing one of the chlamydial effectors. Together, the data suggest that a specific structure on the C. trachomatis inclusion membrane may be responsible for the known interactions of chlamydiae with the microtubule network and resultant effects on centrosome stability.

Structure and function of the contactin-associated protein family in myelinated axons and their relationship with nerve diseases

Directory of Open Access Journals (Sweden)

Yan Zou

2017-01-01

Full Text Available The contactin-associated protein (Caspr family participates in nerve excitation and conduction, and neurotransmitter release in myelinated axons. We analyzed the structures and functions of the Caspr family–CNTNAP1 (Caspr1, CNTNAP2 (Caspr2, CNTNAP3 (Caspr3, CNTNAP4 (Caspr4 and CNTNAP5 (Caspr5, Caspr1–5 is not only involved in the formation of myelinated axons, but also participates in maintaining the stability of adjacent connections. Caspr1 participates in the formation, differentiation, and proliferation of neurons and astrocytes, and in motor control and cognitive function. We also analyzed the relationship between the Caspr family and neurodegenerative diseases, multiple sclerosis, and autoimmune encephalitis. However, the effects of Caspr on disease course and prognosis remain poorly understood. The effects of Caspr on disease diagnosis and treatment need further investigation.

The ubiquitin family meets the Fanconi anemia proteins.

Science.gov (United States)

Renaudin, Xavier; Koch Lerner, Leticia; Menck, Carlos Frederico Martins; Rosselli, Filippo

2016-01-01

Fanconi anaemia (FA) is a hereditary disorder characterized by bone marrow failure, developmental defects, predisposition to cancer and chromosomal abnormalities. FA is caused by biallelic mutations that inactivate genes encoding proteins involved in replication stress-associated DNA damage responses. The 20 FANC proteins identified to date constitute the FANC pathway. A key event in this pathway involves the monoubiquitination of the FANCD2-FANCI heterodimer by the collective action of at least 10 different proteins assembled in the FANC core complex. The FANC core complex-mediated monoubiquitination of FANCD2-FANCI is essential to assemble the heterodimer in subnuclear, chromatin-associated, foci and to regulate the process of DNA repair as well as the rescue of stalled replication forks. Several recent works have demonstrated that the activity of the FANC pathway is linked to several other protein post-translational modifications from the ubiquitin-like family, including SUMO and NEDD8. These modifications are related to DNA damage responses but may also affect other cellular functions potentially related to the clinical phenotypes of the syndrome. This review summarizes the interplay between the ubiquitin and ubiquitin-like proteins and the FANC proteins that constitute a major pathway for the surveillance of the genomic integrity and addresses the implications of their interactions in maintaining genome stability. Copyright © 2016 Elsevier B.V. All rights reserved.

Receptor-like proteins involved in plant disease resistance

NARCIS (Netherlands)

Kruijt, M.; Kock, de M.J.D.; Wit, de P.J.G.M.

2005-01-01

Race-specific resistance in plants against microbial pathogens is governed by several distinct classes of resistance (R) genes. This review focuses on the class that consists of the plasma membrane-bound leucine-rich repeat proteins known as receptor-like proteins (RLPs). The first isolated

Molecular evolution of the keratin associated protein gene family in mammals, role in the evolution of mammalian hair.

Science.gov (United States)

Wu, Dong-Dong; Irwin, David M; Zhang, Ya-Ping

2008-08-23

Hair is unique to mammals. Keratin associated proteins (KRTAPs), which contain two major groups: high/ultrahigh cysteine and high glycine-tyrosine, are one of the major components of hair and play essential roles in the formation of rigid and resistant hair shafts. The KRTAP family was identified as being unique to mammals, and near-complete KRTAP gene repertoires for eight mammalian genomes were characterized in this study. An expanded KRTAP gene repertoire was found in rodents. Surprisingly, humans have a similar number of genes as other primates despite the relative hairlessness of humans. We identified several new subfamilies not previously reported in the high/ultrahigh cysteine KRTAP genes. Genes in many subfamilies of the high/ultrahigh cysteine KRTAP genes have evolved by concerted evolution with frequent gene conversion events, yielding a higher GC base content for these gene sequences. In contrast, the high glycine-tyrosine KRTAP genes have evolved more dynamically, with fewer gene conversion events and thus have a lower GC base content, possibly due to positive selection. Most of the subfamilies emerged early in the evolution of mammals, thus we propose that the mammalian ancestor should have a diverse KRTAP gene repertoire. We propose that hair content characteristics have evolved and diverged rapidly among mammals because of rapid divergent evolution of KRTAPs between species. In contrast, subfamilies of KRTAP genes have been homogenized within each species due to concerted evolution.

Expression of P-glycoprotein, multidrug resistance-associated protein, glutathione-S-transferase pi and p53 in canine transmissible venereal tumor

Directory of Open Access Journals (Sweden)

Daniel G. Gerardi

2014-01-01

Full Text Available The overexpression of proteins P-glycoprotein (P-gp, multidrug resistance-associated protein (MRP1, mutant p53, and the enzyme glutathione-S-transferase (GSTpi are related to resistance to chemotherapy in neoplasms. This study evaluated the expression of these markers by immunohistochemistry in two groups of canine TVT, without history of prior chemotherapy (TVT1, n=9 and in TVTs presented unsatisfactory clinical response to vincristine sulfate (TVT2, n=5. The percentage of specimens positively stained for P-gp, MRP1, GSTpi and p53 were, respectively 88.8%, 0%, 44.5% and 22.2% in TVT1 and 80%, 0%, 80% and 0% in TVT2. In TVT1, one specimen presented positive expression for three markers and four specimens for two markers. In TVT2, three specimens expressed P-gp and GSTpi. In conclusion, the canine TVTs studied expressed the four markers evaluated, but just P-gp and GSTpi were significantly expressed, mainly at cytoplasm and cytoplasm and nuclei, respectively, either before chemotherapy as after vincristine sulfate exposure. Future studies are needed to demonstrate the function of these two markers in conferring multidrug resistance (MDR or predict the response to chemotherapy in canine TVT.

Direct detection of carbapenemase-associated proteins of Acinetobacter baumannii using nanodiamonds coupled with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.

Science.gov (United States)

Chang, Kai-Chih; Chung, Chin-Yi; Yeh, Chen-Hsing; Hsu, Kuo-Hsiu; Chin, Ya-Ching; Huang, Sin-Siang; Liu, Bo-Rong; Chen, Hsi-An; Hu, Anren; Soo, Po-Chi; Peng, Wen-Ping

2018-04-01

The appearance and spread of carbapenem-resistant Acinetobacter baumannii (CRAB) pose a challenge for optimization of antibiotic therapies and outbreak preventions. The carbapenemase production can be detected through culture-based methods (e.g. Modified Hodge Test-MHT) and DNA based methods (e.g. Polymerase Chain Reaction-PCR). The culture-based methods are time-consuming, whereas those of PCR assays need only a few hours but due to its specificity, can only detect known genetic targets encoding carbapenem-resistance genes. Therefore, new approaches to detect carbapenemase-producing A. baumannii are of great importance. Here, we have developed a rapid and novel method using detonation nanodiamonds (DNDs) as a platform for concentration and extraction of A. baumannii carbapenemase-associated proteins prior to matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI TOF-MS) analysis. To concentrate and extract the A. baumannii carbapenemase-associated proteins, we tested several protein precipitation conditions and found a 0.5% trifluoroacetic acid (TFA) solution within the bacterial suspension could result in strong ion signals with DNDs. A total of 66 A. baumannii clinical-isolates including 51 carbapenem-resistant strains and 15 carbapenem-susceptible strains were tested. Our result showed that among the 51 carbapenem-resistant strains 49 strains had a signal at m/z ~40,279 (±87); among the 15 carbapenem-susceptible strains, 4 strains showed a signal at m/z ~40,279. With on-diamond digestion, we confirmed that the captured protein at m/z ~40,279 was related to ADC family extended-spectrum class C beta-lactamase, from A. baumannii. Using this ADC family protein as a biomarker (m/z ~ 40,279) for carbapenem susceptibility testing of A. baumannii, the sensitivity and the specificity could reach 96% and 73% as compared to traditional imipenem susceptibility testing (MIC results). However, the sensitivity and specificity of this method

Structural Insight on the Mechanism of Regulation of the MarR Family of Proteins: High-Resolution Crystal Structure of a Transcriptional Repressor from Methanobacterium thermoautotrophicum

Energy Technology Data Exchange (ETDEWEB)

Saridakis, Vivian; Shahinas, Dea; Xu, Xiaohui; Christendat, Dinesh (York); (Toronto); (CG)

2008-03-31

Transcriptional regulators belonging to the MarR family are characterized by a winged-helix DNA binding domain. These transcriptional regulators regulate the efflux and influx of phenolic agents in bacteria and archaea. In Escherichia coli, MarR regulates the multiple antibiotic resistance operon and its inactivation produces a multiple antibiotic resistance phenotype. In some organisms, active efflux of drug compounds will produce a drug resistance phenotype, whereas in other organisms, active influx of chlorinated hydrocarbons results in their rapid degradation. Although proteins in the MarR family are regulators of important biological processes, their mechanism of action is not well understood and structural information about how phenolic agents regulate the activity of these proteins is lacking. This article presents the three-dimensional structure of a protein of the MarR family, MTH313, in its apo form and in complex with salicylate, a known inactivator. A comparison of these two structures indicates that the mechanism of regulation involves a large conformational change in the DNA binding lobe. Electrophoretic mobility shift assay and biophysical analyses further suggest that salicylate inactivates MTH313 and prevents it from binding to its promoter region.

RStrucFam: a web server to associate structure and cognate RNA for RNA-binding proteins from sequence information.

Science.gov (United States)

Ghosh, Pritha; Mathew, Oommen K; Sowdhamini, Ramanathan

2016-10-07

RNA-binding proteins (RBPs) interact with their cognate RNA(s) to form large biomolecular assemblies. They are versatile in their functionality and are involved in a myriad of processes inside the cell. RBPs with similar structural features and common biological functions are grouped together into families and superfamilies. It will be useful to obtain an early understanding and association of RNA-binding property of sequences of gene products. Here, we report a web server, RStrucFam, to predict the structure, type of cognate RNA(s) and function(s) of proteins, where possible, from mere sequence information. The web server employs Hidden Markov Model scan (hmmscan) to enable association to a back-end database of structural and sequence families. The database (HMMRBP) comprises of 437 HMMs of RBP families of known structure that have been generated using structure-based sequence alignments and 746 sequence-centric RBP family HMMs. The input protein sequence is associated with structural or sequence domain families, if structure or sequence signatures exist. In case of association of the protein with a family of known structures, output features like, multiple structure-based sequence alignment (MSSA) of the query with all others members of that family is provided. Further, cognate RNA partner(s) for that protein, Gene Ontology (GO) annotations, if any and a homology model of the protein can be obtained. The users can also browse through the database for details pertaining to each family, protein or RNA and their related information based on keyword search or RNA motif search. RStrucFam is a web server that exploits structurally conserved features of RBPs, derived from known family members and imprinted in mathematical profiles, to predict putative RBPs from sequence information. Proteins that fail to associate with such structure-centric families are further queried against the sequence-centric RBP family HMMs in the HMMRBP database. Further, all other essential

Early viral replication and induced or constitutive immunity in rainbow trout families with differential resistance to Infectious hematopoietic necrosis virus (IHNV)

Science.gov (United States)

Purcell, M.K.; LaPatra, S.E.; Woodson, J.C.; Kurath, G.; Winton, J.R.

2010-01-01

The main objective of this study was to assess correlates of innate resistance in rainbow trout full-sibling families that differ in susceptibility to Infectious hematopoietic necrosis virus (IHNV). As part of a commercial breeding program, full-sibling families were challenged with IHNV by waterborne exposure at the 1 g size to determine susceptibility to IHNV. Progeny from select families (N = 7 families) that varied in susceptibility (ranging from 32 to 90% cumulative percent mortality (CPM)) were challenged again at the 10 g size by intra-peritoneal injection and overall mortality, early viral replication and immune responses were evaluated. Mortality challenges included 20–40 fish per family while viral replication and immune response studies included 6 fish per family at each time point (24, 48 and 72 h post-infection (hpi)). CPM at the 1 g size was significantly correlated with CPM at the 10 g size, indicating that inherent resistance was a stable trait irrespective of size. In the larger fish, viral load was measured by quantitative reverse-transcriptase PCR in the anterior kidney and was a significant predictor of family disease outcome at 48 hpi. Type I interferon (IFN) transcript levels were significantly correlated with an individual's viral load at 48 and 72 hpi, while type II IFN gene expression was significantly correlated with an individual's viral load at 24 and 48 hpi. Mean family type I but not type II IFN gene expression was weakly associated with susceptibility at 72 hpi. There was no association between mean family susceptibility and the constitutive expression of a range of innate immune genes (e.g. type I and II IFN pathway genes, cytokine and viral recognition receptor genes). The majority of survivors from the challenge had detectable serum neutralizing antibody titers but no trend was observed among families. This result suggests that even the most resistant families experienced sufficient levels of viral replication to trigger specific

Resistance to Inhibitors of Cholinesterase 3 (Ric-3 Expression Promotes Selective Protein Associations with the Human α7-Nicotinic Acetylcholine Receptor Interactome.

Directory of Open Access Journals (Sweden)

Matthew J Mulcahy

Full Text Available The α7-nicotinic acetylcholine receptor (α7-nAChR is a ligand-gated ion channel widely expressed in vertebrates and is associated with numerous physiological functions. As transmembrane ion channels, α7-nAChRs need to be expressed on the surface of the plasma membrane to function. The receptor has been reported to associate with proteins involved with receptor biogenesis, modulation of receptor properties, as well as intracellular signaling cascades and some of these associated proteins may affect surface expression of α7-nAChRs. The putative chaperone resistance to inhibitors of cholinesterase 3 (Ric-3 has been reported to interact with, and enhance the surface expression of, α7-nAChRs. In this study, we identified proteins that associate with α7-nAChRs when Ric-3 is expressed. Using α-bungarotoxin (α-bgtx, we isolated and compared α7-nAChR-associated proteins from two stably transfected, human tumor-derived cell lines: SH-EP1-hα7 expressing human α7-nAChRs and the same cell line further transfected to express Ric-3, SH-EP1-hα7-Ric-3. Mass spectrometric analysis of peptides identified thirty-nine proteins that are associated with α7-nAChRs only when Ric-3 was expressed. Significantly, and consistent with reports of Ric-3 function in the literature, several of the identified proteins are involved in biological processes that may affect nAChR surface expression such as post-translational processing of proteins, protein trafficking, and protein transport. Additionally, proteins affecting the cell cycle, the cytoskeleton, stress responses, as well as cyclic AMP- and inositol triphosphate-dependent signaling cascades were identified. These results illuminate how α-bgtx may be used to isolate and identify α7-nAChRs as well as how the expression of chaperones such as Ric-3 can influence proteins associating with α7-nAChRs. These associating proteins may alter activities of α7-nAChRs to expand their functionally-relevant repertoire as

Mycobacterium tuberculosis whole genome sequencing and protein structure modelling provides insights into anti-tuberculosis drug resistance

KAUST Repository

Phelan, Jody

2016-03-23

Background Combating the spread of drug resistant tuberculosis is a global health priority. Whole genome association studies are being applied to identify genetic determinants of resistance to anti-tuberculosis drugs. Protein structure and interaction modelling are used to understand the functional effects of putative mutations and provide insight into the molecular mechanisms leading to resistance. Methods To investigate the potential utility of these approaches, we analysed the genomes of 144 Mycobacterium tuberculosis clinical isolates from The Special Programme for Research and Training in Tropical Diseases (TDR) collection sourced from 20 countries in four continents. A genome-wide approach was applied to 127 isolates to identify polymorphisms associated with minimum inhibitory concentrations for first-line anti-tuberculosis drugs. In addition, the effect of identified candidate mutations on protein stability and interactions was assessed quantitatively with well-established computational methods. Results The analysis revealed that mutations in the genes rpoB (rifampicin), katG (isoniazid), inhA-promoter (isoniazid), rpsL (streptomycin) and embB (ethambutol) were responsible for the majority of resistance observed. A subset of the mutations identified in rpoB and katG were predicted to affect protein stability. Further, a strong direct correlation was observed between the minimum inhibitory concentration values and the distance of the mutated residues in the three-dimensional structures of rpoB and katG to their respective drugs binding sites. Conclusions Using the TDR resource, we demonstrate the usefulness of whole genome association and convergent evolution approaches to detect known and potentially novel mutations associated with drug resistance. Further, protein structural modelling could provide a means of predicting the impact of polymorphisms on drug efficacy in the absence of phenotypic data. These approaches could ultimately lead to novel resistance

Prioritizing disease candidate proteins in cardiomyopathy-specific protein-protein interaction networks based on "guilt by association" analysis.

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Wan Li

Full Text Available The cardiomyopathies are a group of heart muscle diseases which can be inherited (familial. Identifying potential disease-related proteins is important to understand mechanisms of cardiomyopathies. Experimental identification of cardiomyophthies is costly and labour-intensive. In contrast, bioinformatics approach has a competitive advantage over experimental method. Based on "guilt by association" analysis, we prioritized candidate proteins involving in human cardiomyopathies. We first built weighted human cardiomyopathy-specific protein-protein interaction networks for three subtypes of cardiomyopathies using the known disease proteins from Online Mendelian Inheritance in Man as seeds. We then developed a method in prioritizing disease candidate proteins to rank candidate proteins in the network based on "guilt by association" analysis. It was found that most candidate proteins with high scores shared disease-related pathways with disease seed proteins. These top ranked candidate proteins were related with the corresponding disease subtypes, and were potential disease-related proteins. Cross-validation and comparison with other methods indicated that our approach could be used for the identification of potentially novel disease proteins, which may provide insights into cardiomyopathy-related mechanisms in a more comprehensive and integrated way.

Timing of postexercise protein intake is important for muscle hypertrophy with resistance training in elderly humans

DEFF Research Database (Denmark)

Esmarck, B.; Andersen, J.L.; Olsen, S.

2001-01-01

1. Age-associated loss of skeletal muscle mass and strength can partly be counteracted by resistance training, causing a net synthesis of muscular proteins. Protein synthesis is influenced synergistically by postexercise amino acid supplementation, but the importance of the timing of protein intake...

Multidrug resistance-associated protein 4 is a bile transporter of Clonorchis sinensis simulated by in silico docking.

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Dai, Fuhong; Yoo, Won Gi; Lee, Ji-Yun; Lu, Yanyan; Pak, Jhang Ho; Sohn, Woon-Mok; Hong, Sung-Jong

2017-11-21

Multidrug resistance-associated protein 4 (MRP4) is a member of the C subfamily of the ABC family of ATP-binding cassette (ABC) transporters. MRP4 regulates ATP-dependent efflux of various organic anionic substrates and bile acids out of cells. Since Clonorchis sinensis lives in host's bile duct, accumulation of bile juice can be toxic to the worm's tissues and cells. Therefore, C. sinensis needs bile transporters to reduce accumulation of bile acids within its body. We cloned MRP4 (CsMRP4) from C. sinensis and obtained a cDNA encoding an open reading frame of 1469 amino acids. Phylogenetic analysis revealed that CsMRP4 belonged to the MRP/SUR/CFTR subfamily. A tertiary structure of CsMRP4 was generated by homology modeling based on multiple structures of MRP1 and P-glycoprotein. CsMRP4 had two membrane-spanning domains (MSD1 & 2) and two nucleotide-binding domains (NBD1 & 2) as common structural folds. Docking simulation with nine bile acids showed that CsMRP4 transports bile acids through the inner cavity. Moreover, it was found that CsMRP4 mRNA was more abundant in the metacercariae than in the adults. Mouse immune serum, generated against the CsMRP4-NBD1 (24.9 kDa) fragment, localized CsMRP4 mainly in mesenchymal tissues and oral and ventral suckers of the metacercariae and the adults. Our findings shed new light on MRPs and their homologs and provide a platform for further structural and functional investigations on the bile transporters and parasites' survival.

The Role of Bcl-2 Family Proteins in Therapy Responses of Malignant Astrocytic Gliomas: Bcl2L12 and Beyond

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Fotini M. Kouri

2012-01-01

Full Text Available Glioblastoma (GBM is a highly aggressive and lethal brain cancer with a median survival of less than two years after diagnosis. Hallmarks of GBM tumors include soaring proliferative indices, high levels of angiogenesis, diffuse invasion into normal brain parenchyma, resistance toward therapy-induced apoptosis, and pseudopallisading necrosis. Despite the recent advances in neurosurgery, radiation therapy, and the development of targeted chemotherapeutic regimes, GBM remains one of the deadliest types of cancer. Particularly, the alkylating agent temozolomide (TMZ in combination with radiation therapy prolonged patient survival only marginally, and clinical studies assessing efficacies of targeted therapies, foremost ATP mimetics inhibiting the activity of receptor tyrosine kinases (RTKs, revealed only few initial responders; tumor recurrence is nearly universal, and salvage therapies to combat such progression remain ineffective. Consequently, myriad preclinical and clinical studies began to define the molecular mechanisms underlying therapy resistance of GBM tumors, and pointed to the Bcl-2 protein family, in particular the atypical member Bcl2-Like 12 (Bcl2L12, as important regulators of therapy-induced cell death. This review will discuss the multi-faceted modi operandi of Bcl-2 family proteins, describe their roles in therapy resistance of malignant glioma, and outline current and future drug development efforts to therapeutically target Bcl-2 proteins.

Apical sorting of lysoGPI-anchored proteins occurs independent of association with detergent-resistant membranes but dependent on their N-glycosylation.

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Castillon, Guillaume Alain; Michon, Laetitia; Watanabe, Reika

2013-06-01

Most glycosylphosphatidylinositol-anchored proteins (GPI-APs) are located at the apical surface of epithelial cells. The apical delivery of GPI-APs is believed to result from their association with lipid rafts. We find that overexpression of C-terminally tagged PGAP3 caused predominant production of lysoGPI-APs, an intermediate precursor in the GPI lipid remodeling process in Madin-Darby canine kidney cells. In these cells, produced lysoGPI-APs are not incorporated into detergent-resistant membranes (DRMs) but still are delivered apically, suggesting that GPI-AP association with DRMs is not necessary for apical targeting. In contrast, apical transport of both fully remodeled and lyso forms of GPI-APs is dependent on N-glycosylation, confirming a general role of N-glycans in apical protein transport. We also find that depletion of cholesterol causes apical-to-basolateral retargeting not only of fully remodeled GPI-APs, but also of lysoGPI-APs, as well as endogenous soluble and transmembrane proteins that would normally be targeted to the apical membrane. These findings confirm the essential role for cholesterol in the apical protein targeting and further demonstrate that the mechanism of cholesterol-dependent apical sorting is not related to DRM association of GPI-APs.

Hormone signaling linked to silkmoth sex pheromone biosynthesis involves Ca2+/calmodulin-dependent protein kinase II-mediated phosphorylation of the insect PAT family protein Bombyx mori lipid storage droplet protein-1(BmLsd)

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The structurally-related members of the PAT family of proteins, which are so name based on similarity amongst perilipin, adipophilin/adipocyte differentiation-related protein (ADRP), and tail-interacting protein of 47 kilodaltons (TIP47), are cytoplasmic lipid droplet (LD)-associated proteins charac...

Breast cancer resistance protein is localized at the plasma membrane in mitoxantrone- and topotecan-resistant cell lines

NARCIS (Netherlands)

Scheffer, GL; Maliepaard, M; Pijnenborg, ACLM; van Gastelen, MA; Schroeijers, AB; Allen, JD; Ross, DD; van der Valk, P; Dalton, WS; Schellens, JHM; Scheper, RJ; de Jong, MC

2000-01-01

Tumor cells may display a multidrug resistant phenotype by overexpression of ATP-binding cassette transporters such as multidrug resistance (,MDR1) P-glycoprotein, multidrug resistance protein 1 (MRP1), and breast cancer resistance protein (BCRP). The presence of BCRP has thus far been reported

NSP-CAS Protein Complexes: Emerging Signaling Modules in Cancer.

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Wallez, Yann; Mace, Peter D; Pasquale, Elena B; Riedl, Stefan J

2012-05-01

The CAS (CRK-associated substrate) family of adaptor proteins comprises 4 members, which share a conserved modular domain structure that enables multiple protein-protein interactions, leading to the assembly of intracellular signaling platforms. Besides their physiological role in signal transduction downstream of a variety of cell surface receptors, CAS proteins are also critical for oncogenic transformation and cancer cell malignancy through associations with a variety of regulatory proteins and downstream effectors. Among the regulatory partners, the 3 recently identified adaptor proteins constituting the NSP (novel SH2-containing protein) family avidly bind to the conserved carboxy-terminal focal adhesion-targeting (FAT) domain of CAS proteins. NSP proteins use an anomalous nucleotide exchange factor domain that lacks catalytic activity to form NSP-CAS signaling modules. Additionally, the NSP SH2 domain can link NSP-CAS signaling assemblies to tyrosine-phosphorylated cell surface receptors. NSP proteins can potentiate CAS function by affecting key CAS attributes such as expression levels, phosphorylation state, and subcellular localization, leading to effects on cell adhesion, migration, and invasion as well as cell growth. The consequences of these activities are well exemplified by the role that members of both families play in promoting breast cancer cell invasiveness and resistance to antiestrogens. In this review, we discuss the intriguing interplay between the NSP and CAS families, with a particular focus on cancer signaling networks.

MRP proteins as potential mediators of heavy metal resistance in zebrafish cells.

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Long, Yong; Li, Qing; Wang, Youhui; Cui, Zongbin

2011-04-01

Acquired resistance of mammalian cells to heavy metals is closely relevant to enhanced expression of several multidrug resistance-associated proteins (MRP), but it remains unclear whether MRP proteins confer resistance to heavy metals in zebrafish. In this study, we obtained zebrafish (Danio rerio) fibroblast-like ZF4 cells with resistance to toxic heavy metals after chronic cadmium exposure and selection for 6months. These cadmium-resistant cells (ZF4-Cd) were maintained in 5μM cadmium and displayed cross-resistance to cadmium, mercury, arsenite and arsenate. ZF4-Cd cells remained the resistance to heavy metals after protracted culture in cadmium-free medium. In comparison with ZF4-WT cells, ZF4-Cd cells exhibited accelerated rate of cadmium excretion, enhanced activity of MRP-like transport, elevated expression of abcc2, abcc4 and mt2 genes, and increased content of cellular GSH. Inhibition of MRP-like transport activity, GSH biosynthesis and GST activity significantly attenuated the resistance of ZF4-Cd cells to heavy metals. The results indicate that some of MRP transporters are involved in the efflux of heavy metals conjugated with cellular GSH and thus play crucial roles in heavy metal detoxification of zebrafish cells. Copyright © 2010 Elsevier Inc. All rights reserved.

Herpesviruses dUTPases: A New Family of Pathogen-Associated Molecular Pattern (PAMP Proteins with Implications for Human Disease

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Marshall V. Williams

2016-12-01

Full Text Available The human herpesviruses are ubiquitous viruses and have a prevalence of over 90% in the adult population. Following a primary infection they establish latency and can be reactivated over a person’s lifetime. While it is well accepted that human herpesviruses are implicated in numerous diseases ranging from dermatological and autoimmune disease to cancer, the role of lytic proteins in the pathophysiology of herpesvirus-associated diseases remains largely understudies. Only recently have we begun to appreciate the importance of lytic proteins produced during reactivation of the virus, in particular the deoxyuridine triphosphate nucleotidohydrolases (dUTPase, as key modulators of the host innate and adaptive immune responses. In this review, we provide evidence from animal and human studies of the Epstein–Barr virus as a prototype, supporting the notion that herpesviruses dUTPases are a family of proteins with unique immunoregulatory functions that can alter the inflammatory microenvironment and thus exacerbate the immune pathology of herpesvirus-related diseases including myalgic encephalomyelitis/chronic fatigue syndrome, autoimmune diseases, and cancer.

Mechanosensitive molecular networks involved in transducing resistance exercise-signals into muscle protein accretion

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Emil Rindom

2016-11-01

Full Text Available Loss of skeletal muscle myofibrillar protein with disease and/or inactivity can severely deteriorate muscle strength and function. Strategies to counteract wasting of muscle myofibrillar protein are therefore desirable and invite for considerations on the potential superiority of specific modes of resistance exercise and/or the adequacy of low load resistance exercise regimens as well as underlying mechanisms. In this regard, delineation of the potentially mechanosensitive molecular mechanisms underlying muscle protein synthesis (MPS, may contribute to understanding on how differentiated resistance exercise can transduce a mechanical signal into stimulation of muscle accretion. Recent findings suggest specific upstream exercise-induced mechano-sensitive myocellular signaling pathways to converge on mammalian target of rapamycin complex 1 (mTORC1, to influence MPS. This may e.g. implicate mechanical activation of signaling through a diacylglycerol kinase (DGKζ-phosphatidic acid (PA axis or implicate integrin deformation to signal through a Focal adhesion kinase (FAK-Tuberous Sclerosis Complex 2TSC2-Ras homolog enriched in brain (Rheb axis. Moreover, since initiation of translation is reliant on mRNA, it is also relevant to consider potentially mechanosensitive signaling pathways involved in muscle myofibrillar gene transcription and whether some of these pathways converge with those affecting mTORC1 activation for MPS. In this regard, recent findings suggest how mechanical stress may implicate integrin deformation and/or actin dynamics to signal through a Ras homolog gene family member A protein (RhoA-striated muscle activator of Rho signaling (STARS axis or how it may implicate deformation of Notch to affect Bone Morphogenetic Protein (BMP signaling through a small mother of decapentaplegic (Smad axis.

SigniSite: Identification of residue-level genotype-phenotype correlations in protein multiple sequence alignments

DEFF Research Database (Denmark)

Jessen, Leon Ivar; Hoof, Ilka; Lund, Ole

2013-01-01

Site does not require any pre-definition of subgroups or binary classification. Input is a set of protein sequences where each sequence has an associated real number, quantifying a given phenotype. SigniSite will then identify which amino acid residues are significantly associated with the data set......) using a set of human immunodeficiency virus protease-inhibitor genotype–phenotype data and corresponding resistance mutation scores from the Stanford University HIV Drug Resistance Database, and a data set of protein families with experimentally annotated SDPs. For both data sets, SigniSite was found...

Effects of whey protein supplement in the elderly submitted to resistance training: systematic review and meta-analysis.

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Colonetti, Tamy; Grande, Antonio Jose; Milton, Karen; Foster, Charlie; Alexandre, Maria Cecilia Manenti; Uggioni, Maria Laura Rodrigues; Rosa, Maria Inês da

2017-05-01

We performed a systematic review to map the evidence and analyze the effect of whey protein supplementation in the elderly submitted to resistance training. A comprehensive search on Medline, LILACS, EMBASE, and the Cochrane Library for relevant publications was conducted until August 2015. The terms used in the search were: "Resistance training"; "Whey protein"; "Elderly". A total of 632 studies were screened. Five studies were included composing a sample of 391 patients. The supplement whey protein was associated with higher total protein ingestion 9.40 (95% CI: 4.03-14.78), and with an average change in plasma leucine concentration. The supplementation was also associated with increased mixed muscle protein synthesis 1.26 (95% CI: 0.46-2.07) compared to the control group. We observed an increase in total protein intake, resulting in increased concentration of leucine and mixed muscle protein fractional synthesis rate.

R-Flurbiprofen Traps Prostaglandins within Cells by Inhibition of Multidrug Resistance-Associated Protein-4.

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Wobst, Ivonne; Ebert, Lisa; Birod, Kerstin; Wegner, Marthe-Susanna; Hoffmann, Marika; Thomas, Dominique; Angioni, Carlo; Parnham, Michael J; Steinhilber, Dieter; Tegeder, Irmgard; Geisslinger, Gerd; Grösch, Sabine

2016-12-30

R -flurbiprofen is the non-COX-inhibiting enantiomer of flurbiprofen and is not converted to S -flurbiprofen in human cells. Nevertheless, it reduces extracellular prostaglandin E₂ (PGE₂) in cancer or immune cell cultures and human extracellular fluid. Here, we show that R -flurbiprofen acts through a dual mechanism: (i) it inhibits the translocation of cPLA 2α to the plasma membrane and thereby curtails the availability of arachidonic acid and (ii) R -flurbiprofen traps PGE₂ inside of the cells by inhibiting multidrug resistance-associated protein 4 (MRP4, ABCC4), which acts as an outward transporter for prostaglandins. Consequently, the effects of R -flurbiprofen were mimicked by RNAi-mediated knockdown of MRP4. Our data show a novel mechanism by which R -flurbiprofen reduces extracellular PGs at physiological concentrations, particularly in cancers with high levels of MRP4, but the mechanism may also contribute to its anti-inflammatory and immune-modulating properties and suggests that it reduces PGs in a site- and context-dependent manner.

THE ROLE OF MULTIDRUG RESISTANCE ASSOCIATED PROTEIN (MRP) IN THE BLOOD-BRAIN BARRIER AND OPIOID ANALGESIA

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Su, Wendy; Pasternak, Gavril W.

2013-01-01

The blood brain barrier protects the brain from circulating compounds and drugs. The ATP-binding cassette (ABC) transporter P-glycoprotein (Pgp) is involved with the barrier, both preventing the influx of agent from the blood into the brain and facilitating the efflux of compounds from the brain into the blood, raising the possibility of a similar role for other transporters. Multidrug resistance associated protein (MRP), a 190 kDa protein similar to Pgp is also ABC transport that has been implicated in the blood brain barrier. The current study explores its role in opioid action. Immunohistochemically, it is localized in the choroid plexus in ratsand can be selectively downregulated by antisense treatment at both the level of mRNA, as shown by RT-PCR, and protein, as demonstrated immunohistochemically. Behaviorally, downregulation of MRP significantly enhances the analgesic potency of systemic morphine in MRP knockout mice and in antisense-treated rats by lowering the blood brain barrier. Following intracerebroventricular administration, a number of compounds, including some opioids, are rapidly secreted from the brain into the blood where they contribute to the overall analgesic effects by activating peripheral systems. MRP plays a role in this efflux. Downregulating MRP expression leads to a corresponding decrease in the transport and a diminished analgesic response from opioids administered intracerebroventricularly. Thus, the transporter protein MRP plays a role in maintaining the blood-brain barrier and modulates the activity of opioids. PMID:23508590

In silico modeling of the yeast protein and protein family interaction network

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Goh, K.-I.; Kahng, B.; Kim, D.

2004-03-01

Understanding of how protein interaction networks of living organisms have evolved or are organized can be the first stepping stone in unveiling how life works on a fundamental ground. Here we introduce an in silico ``coevolutionary'' model for the protein interaction network and the protein family network. The essential ingredient of the model includes the protein family identity and its robustness under evolution, as well as the three previously proposed: gene duplication, divergence, and mutation. This model produces a prototypical feature of complex networks in a wide range of parameter space, following the generalized Pareto distribution in connectivity. Moreover, we investigate other structural properties of our model in detail with some specific values of parameters relevant to the yeast Saccharomyces cerevisiae, showing excellent agreement with the empirical data. Our model indicates that the physical constraints encoded via the domain structure of proteins play a crucial role in protein interactions.

Initial infection of roots and leaves reveals different resistance phenotypes associated with coat protein gene-mediated resistance to Potato mop-top virus.

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Germundsson, Anna; Sandgren, Maria; Barker, Hugh; Savenkov, Eugene I; Valkonen, Jari P T

2002-05-01

Resistance to the pomovirus Potato mop-top virus (PMTV) was studied in potato (Solanum tuberosum cv. Saturna) and Nicotiana benthamiana transformed with the coat protein (CP) gene of PMTV. The incidence of PMTV infections was reduced in tubers of the CP-transgenic potatoes grown in the field in soil infested with the viruliferous vector, Spongospora subterranea. However, in those tubers that were infected, all three virus RNAs were detected and virus titres were high. The CP-transgenic N. benthamiana plants were inoculated with PMTV using two methods. Following mechanical inoculation of leaves, no RNA 3 (the CP-encoding RNA homologous to the transgene) was detected in leaves, but in some plants low amounts of RNA 3 were detected in roots; RNA 2 was readily detected in leaves and roots of several plants. Inoculation of roots using viruliferous S. subterranea resulted in infection of roots in all plants and the three PMTV RNAs were detected. However, no systemic movement of PMTV from roots to the above-ground parts was observed, indicating a novel expression of resistance. These data indicate that the CP gene-mediated resistance to PMTV specifically restricts accumulation of PMTV RNA 3, and is more effective in leaves than roots. Furthermore, expression of resistance is different depending on whether leaves or roots are inoculated. Data do not exclude the possibility that both a protein-mediated and an RNA-mediated resistance mechanism are involved.

Neisseria meningitidis rifampicin resistant strains: analysis of protein differentially expressed

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Schininà Maria

2010-09-01

Full Text Available Abstract Background Several mutations have been described as responsible for rifampicin resistance in Neisseria meningitidis. However, the intriguing question on why these strains are so rare remains open. The aim of this study was to investigate the protein content and to identify differential expression in specific proteins in two rifampicin resistant and one susceptible meningococci using two-dimensional electrophoresis (2-DE combined with mass spectrometry. Results In our experimental conditions, able to resolve soluble proteins with an isoelectric point between 4 and 7, twenty-three proteins have been found differentially expressed in the two resistant strains compared to the susceptible. Some of them, involved in the main metabolic pathways, showed an increased expression, mainly in the catabolism of pyruvate and in the tricarboxylic acid cycle. A decreased expression of proteins belonging to gene regulation and to those involved in the folding of polypeptides has also been observed. 2-DE analysis showed the presence of four proteins displaying a shift in their isoelectric point in both resistant strains, confirmed by the presence of amino acid changes in the sequence analysis, absent in the susceptible. Conclusions The analysis of differentially expressed proteins suggests that an intricate series of events occurs in N. meningitidis rifampicin resistant strains and the results here reported may be considered a starting point in understanding their decreased invasion capacity. In fact, they support the hypothesis that the presence of more than one protein differentially expressed, having a role in the metabolism of the meningococcus, influences its ability to infect and to spread in the population. Different reports have described and discussed how a drug resistant pathogen shows a high biological cost for survival and that may also explain why, for some pathogens, the rate of resistant organisms is relatively low considering the

Involvement of the Eukaryote-Like Kinase-Phosphatase System and a Protein That Interacts with Penicillin-Binding Protein 5 in Emergence of Cephalosporin Resistance in Cephalosporin-Sensitive Class A Penicillin-Binding Protein Mutants in Enterococcus faecium

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Charlene Desbonnet

2016-04-01

Full Text Available The intrinsic resistance of Enterococcus faecium to ceftriaxone and cefepime (here referred to as “cephalosporins” is reliant on the presence of class A penicillin-binding proteins (Pbps PbpF and PonA. Mutants lacking these Pbps exhibit cephalosporin susceptibility that is reversible by exposure to penicillin and by selection on cephalosporin-containing medium. We selected two cephalosporin-resistant mutants (Cro1 and Cro2 of class A Pbp-deficient E. faecium CV598. Genome analysis revealed changes in the serine-threonine kinase Stk in Cro1 and a truncation in the associated phosphatase StpA in Cro2 whose respective involvements in resistance were confirmed in separate complementation experiments. In an additional effort to identify proteins linked to cephalosporin resistance, we performed tandem affinity purification using Pbp5 as bait in penicillin-exposed E. faecium; these experiments yielded a protein designated Pbp5-associated protein (P5AP. Transcription of the P5AP gene was increased after exposure to penicillin in wild-type strains and in Cro2 and suppressed in Cro2 complemented with the wild-type stpA. Transformation of class A Pbp-deficient strains with the plasmid-carried P5AP gene conferred cephalosporin resistance. These data suggest that Pbp5-associated cephalosporin resistance in E. faecium devoid of typical class A Pbps is related to the presence of P5AP, whose expression is influenced by the activity of the serine-threonine phosphatase/kinase system.

Insect Resistance to Bacillus thuringiensis Toxin Cry2Ab Is Conferred by Mutations in an ABC Transporter Subfamily A Protein.

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Wee Tek Tay

2015-11-01

Full Text Available The use of conventional chemical insecticides and bacterial toxins to control lepidopteran pests of global agriculture has imposed significant selection pressure leading to the rapid evolution of insecticide resistance. Transgenic crops (e.g., cotton expressing the Bt Cry toxins are now used world wide to control these pests, including the highly polyphagous and invasive cotton bollworm Helicoverpa armigera. Since 2004, the Cry2Ab toxin has become widely used for controlling H. armigera, often used in combination with Cry1Ac to delay resistance evolution. Isolation of H. armigera and H. punctigera individuals heterozygous for Cry2Ab resistance in 2002 and 2004, respectively, allowed aspects of Cry2Ab resistance (level, fitness costs, genetic dominance, complementation tests to be characterised in both species. However, the gene identity and genetic changes conferring this resistance were unknown, as was the detailed Cry2Ab mode of action. No cross-resistance to Cry1Ac was observed in mutant lines. Biphasic linkage analysis of a Cry2Ab-resistant H. armigera family followed by exon-primed intron-crossing (EPIC marker mapping and candidate gene sequencing identified three independent resistance-associated INDEL mutations in an ATP-Binding Cassette (ABC transporter gene we named HaABCA2. A deletion mutation was also identified in the H. punctigera homolog from the resistant line. All mutations truncate the ABCA2 protein. Isolation of further Cry2Ab resistance alleles in the same gene from field H. armigera populations indicates unequal resistance allele frequencies and the potential for Bt resistance evolution. Identification of the gene involved in resistance as an ABC transporter of the A subfamily adds to the body of evidence on the crucial role this gene family plays in the mode of action of the Bt Cry toxins. The structural differences between the ABCA2, and that of the C subfamily required for Cry1Ac toxicity, indicate differences in the

Resistance training reduces whole-body protein turnover and improves net protein retention in untrained young males.

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Hartman, Joseph W; Moore, Daniel R; Phillips, Stuart M

2006-10-01

It is thought that resistance exercise results in an increased need for dietary protein; however, data also exists to support the opposite conclusion. The purpose of this study was to determine the impact of resistance exercise training on protein metabolism in novices with the hypothesis that resistance training would reduce protein turnover and improve whole-body protein retention. Healthy males (n = 8, 22 +/- 1 y, BMI = 25.3 +/- 1.8 kg.m(-2)) participated in a progressive whole-body split routine resistance-training program 5d/week for 12 weeks. Before (PRE) and after (POST) the training, oral [15N]-glycine ingestion was used to assess nitrogen flux (Q), protein synthesis (PS), protein breakdown (PB), and net protein balance (NPB = PS-PB). Macronutrient intake was controlled over a 5d period PRE and POST, while estimates of protein turnover and urinary nitrogen balance (N(bal) = N(in) - urine N(out)) were conducted. Bench press and leg press increased 40% and 50%, respectively (p training-induced increases in both NPB (PRE = 0.22 +/- 0.13 g.kg(-1).d(-1); POST = 0.54 +/- 0.08 g.kg(-1).d(-1)) and urinary nitrogen balance (PRE = 2.8 +/- 1.7 g N.d(-1); POST = 6.5 +/- 0.9 g N.d(-1)) were observed. A program of resistance training that induced significant muscle hypertrophy resulted in reductions of both whole-body PS and PB, but an improved NPB, which favoured the accretion of skeletal muscle protein. Urinary nitrogen balance increased after training. The reduction in PS and PB and a higher NPB in combination with an increased nitrogen balance after training suggest that dietary requirements for protein in novice resistance-trained athletes are not higher, but lower, after resistance training.

Upregulation of human heme oxygenase gene expression by Ets-family proteins.

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Deramaudt, B M; Remy, P; Abraham, N G

1999-03-01

Overexpression of human heme oxygenase-1 has been shown to have the potential to promote EC proliferation and angiogenesis. Since Ets-family proteins have been shown to play an important role in angiogenesis, we investigated the presence of ETS binding sites (EBS), GGAA/T, and ETS protein contributing to human HO-1 gene expression. Several chloramphenicol acetyltransferase constructs were examined in order to analyze the effect of ETS family proteins on the transduction of HO-1 in Xenopus oocytes and in microvessel endothelial cells. Heme oxygenase promoter activity was up-regulated by FLI-1ERGETS-1 protein(s). Chloramphenicol acetyltransferase (CAT) assays demonstrated that the promoter region (-1500 to +19) contains positive and negative control elements and that all three members of the ETS protein family were responsible for the up-regulation of HHO-1. Electrophoretic mobility shift assays (EMSA), performed with nuclear extracts from endothelial cells overexpressing HHO-1 gene, and specific HHO-1 oligonucleotides probes containing putative EBS resulted in a specific and marked bandshift. Synergistic binding was observed in EMSA between AP-1 on the one hand, FLI-1, ERG, and ETS-1 protein on the other. Moreover, 5'-deletion analysis demonstrated the existence of a negative control element of HHO-1 expression located between positions -1500 and -120 on the HHO-1 promoter. The presence of regulatory sequences for transcription factors such as ETS-1, FLI-1, or ERG, whose activity is associated with cell proliferation, endothelial cell differentiation, and matrix metalloproteinase transduction, may be an indication of the important role that HO-1 may play in coronary collateral circulation, tumor growth, angiogenesis, and hemoglobin-induced endothelial cell injuries.

Inverse association between soya food consumption and insulin resistance in Japanese adults.

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Nakamoto, Mariko; Uemura, Hirokazu; Sakai, Tohru; Katsuura-Kamano, Sakurako; Yamaguchi, Miwa; Hiyoshi, Mineyoshi; Arisawa, Kokichi

2015-08-01

The purpose of the present study was to examine the association between soya food consumption and insulin resistance using baseline data of the Japan Multi-Institutional Collaborative Cohort (J-MICC) Study in Tokushima, Japan. This cross-sectional study included 1274 subjects, aged 34-70 years at baseline, living in Tokushima Prefecture between 2008 and 2013. Fasting blood samples were collected and information on lifestyle characteristics including soya food intake and medical history were obtained using a structured self-administered questionnaire. The homeostasis model assessment of insulin resistance (HOMA-IR) was measured and those with HOMA-IR ≥ 2.5 were defined as having insulin resistance. Multiple logistic regression models were used to analyse the association between soya product intake and the prevalence of insulin resistance. Rural communities located in Tokushima Prefecture, Japan, between 2008 and 2013. A total of 1148 adults (565 men and 583 women), aged 34-70 years. The frequency of intake of miso soup, total non-fried soya products and total soya products showed significant inverse dose-response relationships with insulin resistance, after adjustments for potential confounders. When soya product intake was calculated as soya protein and isoflavone, the odds ratios of insulin resistance decreased significantly as the estimated intake of soya protein increased. Furthermore, significant inverse dose-response relationships were observed for total non-fried soya products and total soya products, after adjustment for total vegetable or total fibre consumption. The present results indicate that the intake of soya products and non-fried soya products is associated with reduced insulin resistance in the Japanese population.

Integral and peripheral association of proteins and protein complexes with Yersinia pestis inner and outer membranes

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Bunai Christine L

2009-02-01

Full Text Available Abstract Yersinia pestis proteins were sequentially extracted from crude membranes with a high salt buffer (2.5 M NaBr, an alkaline solution (180 mM Na2CO3, pH 11.3 and membrane denaturants (8 M urea, 2 M thiourea and 1% amidosulfobetaine-14. Separation of proteins by 2D gel electrophoresis was followed by identification of more than 600 gene products by MS. Data from differential 2D gel display experiments, comparing protein abundances in cytoplasmic, periplasmic and all three membrane fractions, were used to assign proteins found in the membrane fractions to three protein categories: (i integral membrane proteins and peripheral membrane proteins with low solubility in aqueous solutions (220 entries; (ii peripheral membrane proteins with moderate to high solubility in aqueous solutions (127 entries; (iii cytoplasmic or ribosomal membrane-contaminating proteins (80 entries. Thirty-one proteins were experimentally associated with the outer membrane (OM. Circa 50 proteins thought to be part of membrane-localized, multi-subunit complexes were identified in high Mr fractions of membrane extracts via size exclusion chromatography. This data supported biologically meaningful assignments of many proteins to the membrane periphery. Since only 32 inner membrane (IM proteins with two or more predicted transmembrane domains (TMDs were profiled in 2D gels, we resorted to a proteomic analysis by 2D-LC-MS/MS. Ninety-four additional IM proteins with two or more TMDs were identified. The total number of proteins associated with Y. pestis membranes increased to 456 and included representatives of all six β-barrel OM protein families and 25 distinct IM transporter families.

Identification and analysis of YELLOW protein family genes in the silkworm, Bombyx mori

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Yi Yong-Zhu

2006-08-01

Full Text Available Abstract Background The major royal jelly proteins/yellow (MRJP/YELLOW family possesses several physiological and chemical functions in the development of Apis mellifera and Drosophila melanogaster. Each protein of the family has a conserved domain named MRJP. However, there is no report of MRJP/YELLOW family proteins in the Lepidoptera. Results Using the YELLOW protein sequence in Drosophila melanogaster to BLAST silkworm EST database, we found a gene family composed of seven members with a conserved MRJP domain each and named it YELLOW protein family of Bombyx mori. We completed the cDNA sequences with RACE method. The protein of each member possesses a MRJP domain and a putative cleavable signal peptide consisting of a hydrophobic sequence. In view of genetic evolution, the whole Bm YELLOW protein family composes a monophyletic group, which is distinctly separate from Drosophila melanogaster and Apis mellifera. We then showed the tissue expression profiles of Bm YELLOW protein family genes by RT-PCR. Conclusion A Bombyx mori YELLOW protein family is found to be composed of at least seven members. The low homogeneity and unique pattern of gene expression by each member among the family ensure us to prophesy that the members of Bm YELLOW protein family would play some important physiological functions in silkworm development.

BAG3-mediated Mcl-1 stabilization contributes to drug resistance via interaction with USP9X in ovarian cancer.

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Habata, Shutaro; Iwasaki, Masahiro; Sugio, Asuka; Suzuki, Miwa; Tamate, Masato; Satohisa, Seiro; Tanaka, Ryoichi; Saito, Tsuyoshi

2016-07-01

Paclitaxel in combination with carboplatin improves survival among patients with susceptible ovarian cancers, but no strategy has been established against resistant ovarian cancers. BAG3 (Bcl-2-associated athanogene 3) is one of six BAG family proteins, which are involved in such cellular processes as proliferation, migration and apoptosis. In addition, expression of BAG3 with Mcl-1, a Bcl-2 family protein, reportedly associates with resistance to chemotherapy. Our aim in this study was to evaluate the functional role of BAG3 and Mcl-1 in ovarian cancer chemoresistance and explore possible new targets for treatment. We found that combined expression of BAG3 and Mcl-1 was significantly associated with a poor prognosis in ovarian cancer patients. In vitro, BAG3 knockdown in ES2 clear ovarian cancer cells significantly increased the efficacy of paclitaxel in combination with the Mcl-1 antagonist MIM1, with or without the Bcl-2 family antagonist ABT737. Moreover, BAG3 was found to positively regulate Mcl-1 levels by binding to and inhibiting USP9X. Our data show that BAG3 and Mcl-1 are key mediators of resistance to chemotherapy in ovarian cancer. In BAG3 knockdown ES2 clear ovarian cancer cells, combination with ABT737 and MIM1 enhanced the efficacy of paclitaxel. These results suggest that inhibiting BAG3 in addition to anti-apoptotic Bcl-2 family proteins may be a useful therapeutic strategy for the treatment of chemoresistant ovarian cancers.

ErpC, a member of the complement regulator-acquiring family of surface proteins from Borrelia burgdorferi, possesses an architecture previously unseen in this protein family

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Caesar, Joseph J. E.; Johnson, Steven; Kraiczy, Peter; Lea, Susan M.

2013-01-01

The structure of ErpC, a member of the complement regulator-acquiring surface protein family from B. burgdorferi, has been solved, providing insights into the strategies of complement evasion by this zoonotic bacterium and suggesting a common architecture for other members of this protein family. Borrelia burgdorferi is a spirochete responsible for Lyme disease, the most commonly occurring vector-borne disease in Europe and North America. The bacterium utilizes a set of proteins, termed complement regulator-acquiring surface proteins (CRASPs), to aid evasion of the human complement system by recruiting and presenting complement regulator factor H on its surface in a manner that mimics host cells. Presented here is the atomic resolution structure of a member of this protein family, ErpC. The structure provides new insights into the mechanism of recruitment of factor H and other factor H-related proteins by acting as a molecular mimic of host glycosaminoglycans. It also describes the architecture of other CRASP proteins belonging to the OspE/F-related paralogous protein family and suggests that they have evolved to bind specific complement proteins, aiding survival of the bacterium in different hosts

The SGS3 protein involved in PTGS finds a family

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Bateman Alex

2002-08-01

Full Text Available Abstract Background Post transcriptional gene silencing (PTGS is a recently discovered phenomenon that is an area of intense research interest. Components of the PTGS machinery are being discovered by genetic and bioinformatics approaches, but the picture is not yet complete. Results The gene for the PTGS impaired Arabidopsis mutant sgs3 was recently cloned and was not found to have similarity to any other known protein. By a detailed analysis of the sequence of SGS3 we have defined three new protein domains: the XH domain, the XS domain and the zf-XS domain, that are shared with a large family of uncharacterised plant proteins. This work implicates these plant proteins in PTGS. Conclusion The enigmatic SGS3 protein has been found to contain two predicted domains in common with a family of plant proteins. The other members of this family have been predicted to be transcription factors, however this function seems unlikely based on this analysis. A bioinformatics approach has implicated a new family of plant proteins related to SGS3 as potential candidates for PTGS related functions.

Two familial ALS proteins function in prevention/repair of transcription-associated DNA damage.

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Hill, Sarah J; Mordes, Daniel A; Cameron, Lisa A; Neuberg, Donna S; Landini, Serena; Eggan, Kevin; Livingston, David M

2016-11-29

Amyotrophic lateral sclerosis (ALS) is a progressive motor neuron dysfunction disease that leads to paralysis and death. There is currently no established molecular pathogenesis pathway. Multiple proteins involved in RNA processing are linked to ALS, including FUS and TDP43, and we propose a disease mechanism in which loss of function of at least one of these proteins leads to an accumulation of transcription-associated DNA damage contributing to motor neuron cell death and progressive neurological symptoms. In support of this hypothesis, we find that FUS or TDP43 depletion leads to increased sensitivity to a transcription-arresting agent due to increased DNA damage. Thus, these proteins normally contribute to the prevention or repair of transcription-associated DNA damage. In addition, both FUS and TDP43 colocalize with active RNA polymerase II at sites of DNA damage along with the DNA damage repair protein, BRCA1, and FUS and TDP43 participate in the prevention or repair of R loop-associated DNA damage, a manifestation of aberrant transcription and/or RNA processing. Gaining a better understanding of the role(s) that FUS and TDP43 play in transcription-associated DNA damage could shed light on the mechanisms underlying ALS pathogenesis.

The ALMT Gene Family Performs Multiple Functions in Plants

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Jie Liu

2018-02-01

Full Text Available The aluminium activated malate transporter (ALMT gene family is named after the first member of the family identified in wheat (Triticum aestivum L.. The product of this gene controls resistance to aluminium (Al toxicity. ALMT genes encode transmembrane proteins that function as anion channels and perform multiple functions involving the transport of organic anions (e.g., carboxylates and inorganic anions in cells. They share a PF11744 domain and are classified in the Fusaric acid resistance protein-like superfamily, CL0307. The proteins typically have five to seven transmembrane regions in the N-terminal half and a long hydrophillic C-terminal tail but predictions of secondary structure vary. Although widely spread in plants, relatively little information is available on the roles performed by other members of this family. In this review, we summarized functions of ALMT gene families, including Al resistance, stomatal function, mineral nutrition, microbe interactions, fruit acidity, light response and seed development.

Hepatocyte SLAMF3 reduced specifically the multidrugs resistance protein MRP-1 and increases HCC cells sensitization to anti-cancer drugs.

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Fouquet, Grégory; Debuysscher, Véronique; Ouled-Haddou, Hakim; Eugenio, Mélanie Simoes; Demey, Baptiste; Singh, Amrathlal Rabbind; Ossart, Christèle; Al Bagami, Mohammed; Regimbeau, Jean-Marc; Nguyen-Khac, Eric; Naassila, Mickael; Marcq, Ingrid; Bouhlal, Hicham

2016-05-31

Multidrug resistance MDR proteins (MRPs) are members of the C family of a group of proteins named ATP binding cassette (ABC) transporters. MRPs can transport drugs including anticancer drugs, nucleoside analogs, antimetabolites and tyrosine kinase inhibitors. Drugs used in HCC therapy, such as tyrosine kinase inhibitor sorafenib, are substrates of uptake and/or efflux transporters. Variable expression of MRPs at the plasma membrane of tumor cells may contribute to drug resistance and subsequent clinical response. Recently, we reported that the hepatocyte SLAMF3 expression (Signaling Lymphocytic Activation Molecule Family member 3) was reduced in tumor cells from hepatocellular carcinoma (HCC) compared to its high expression in adjacent tissues. In the present study, we make a strong correlation between induced SLAMF3 overexpression and the specific loss of MRP-1 expression and its functionalities as a drugs resistance transporter. No changes were observed on expression of ABCG2 and MDR. More importantly, we highlight a strong inverse correlation between MRP-1 and SLAMF3 expression in patients with HCC. We propose that the SLAMF3 overexpression in cancerous cells could represent a potential therapeutic strategy to improve the drugs sensibility of resistant cells and thus control the therapeutic failure in HCC patients.

Receptor-interacting protein (RIP) kinase family

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Zhang, Duanwu; Lin, Juan; Han, Jiahuai

2010-01-01

Receptor-interacting protein (RIP) kinases are a group of threonine/serine protein kinases with a relatively conserved kinase domain but distinct non-kinase regions. A number of different domain structures, such as death and caspase activation and recruitment domain (CARD) domains, were found in different RIP family members, and these domains should be keys in determining the specific function of each RIP kinase. It is known that RIP kinases participate in different biological processes, including those in innate immunity, but their downstream substrates are largely unknown. This review will give an overview of the structures and functions of RIP family members, and an update of recent progress in RIP kinase research. PMID:20383176

Evolution of the MAGUK protein gene family in premetazoan lineages

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Ruiz-Trillo Iñaki

2010-04-01

Full Text Available Abstract Background Cell-to-cell communication is a key process in multicellular organisms. In multicellular animals, scaffolding proteins belonging to the family of membrane-associated guanylate kinases (MAGUK are involved in the regulation and formation of cell junctions. These MAGUK proteins were believed to be exclusive to Metazoa. However, a MAGUK gene was recently identified in an EST survey of Capsaspora owczarzaki, an unicellular organism that branches off near the metazoan clade. To further investigate the evolutionary history of MAGUK, we have undertook a broader search for this gene family using available genomic sequences of different opisthokont taxa. Results Our survey and phylogenetic analyses show that MAGUK proteins are present not only in Metazoa, but also in the choanoflagellate Monosiga brevicollis and in the protist Capsaspora owczarzaki. However, MAGUKs are absent from fungi, amoebozoans or any other eukaryote. The repertoire of MAGUKs in Placozoa and eumetazoan taxa (Cnidaria + Bilateria is quite similar, except for one class that is missing in Trichoplax, while Porifera have a simpler MAGUK repertoire. However, Vertebrata have undergone several independent duplications and exhibit two exclusive MAGUK classes. Three different MAGUK types are found in both M. brevicollis and C. owczarzaki: DLG, MPP and MAGI. Furthermore, M. brevicollis has suffered a lineage-specific diversification. Conclusions The diversification of the MAGUK protein gene family occurred, most probably, prior to the divergence between Metazoa+choanoflagellates and the Capsaspora+Ministeria clade. A MAGI-like, a DLG-like, and a MPP-like ancestral genes were already present in the unicellular ancestor of Metazoa, and new gene members have been incorporated through metazoan evolution within two major periods, one before the sponge-eumetazoan split and another within the vertebrate lineage. Moreover, choanoflagellates have suffered an independent MAGUK

Silencing of the major family of NBS-LRR-encoding genes in lettuce results in the loss of multiple resistance specificities.

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Wroblewski, Tadeusz; Piskurewicz, Urszula; Tomczak, Anna; Ochoa, Oswaldo; Michelmore, Richard W

2007-09-01

The RGC2 gene cluster in lettuce (Lactuca sativa) is one of the largest known families of genes encoding nucleotide binding site-leucine-rich repeat (NBS-LRR) proteins. One of its members, RGC2B, encodes Dm3 which determines resistance to downy mildew caused by the oomycete Bremia lactucae carrying the cognate avirulence gene, Avr3. We developed an efficient strategy for analysis of this large family of low expressed genes using post-transcriptional gene silencing (PTGS). We transformed lettuce cv. Diana (carrying Dm3) using chimeric gene constructs designed to simultaneously silence RGC2B and the GUS reporter gene via the production of interfering hairpin RNA (ihpRNA). Transient assays of GUS expression in leaves accurately predicted silencing of both genes and were subsequently used to assay silencing in transgenic T(1) plants and their offspring. Levels of mRNA were reduced not only for RGC2B but also for all seven diverse RGC2 family members tested. We then used the same strategy to show that the resistance specificity encoded by the genetically defined Dm18 locus in lettuce cv. Mariska is the result of two resistance specificities, only one of which was silenced by ihpRNA derived from RGC2B. Analysis of progeny from crosses between transgenic, silenced tester stocks and lettuce accessions carrying other resistance genes previously mapped to the RGC2 locus indicated that two additional resistance specificities to B. lactucae, Dm14 and Dm16, as well as resistance to lettuce root aphid (Pemphigus bursarius L.), Ra, are encoded by RGC2 family members.

Multidrug resistance-associated protein 4 is a bile transporter of Clonorchis sinensis simulated by in silico docking

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Fuhong Dai

2017-11-01

Full Text Available Abstract Background Multidrug resistance-associated protein 4 (MRP4 is a member of the C subfamily of the ABC family of ATP-binding cassette (ABC transporters. MRP4 regulates ATP-dependent efflux of various organic anionic substrates and bile acids out of cells. Since Clonorchis sinensis lives in host’s bile duct, accumulation of bile juice can be toxic to the worm’s tissues and cells. Therefore, C. sinensis needs bile transporters to reduce accumulation of bile acids within its body. Results We cloned MRP4 (CsMRP4 from C. sinensis and obtained a cDNA encoding an open reading frame of 1469 amino acids. Phylogenetic analysis revealed that CsMRP4 belonged to the MRP/SUR/CFTR subfamily. A tertiary structure of CsMRP4 was generated by homology modeling based on multiple structures of MRP1 and P-glycoprotein. CsMRP4 had two membrane-spanning domains (MSD1 & 2 and two nucleotide-binding domains (NBD1 & 2 as common structural folds. Docking simulation with nine bile acids showed that CsMRP4 transports bile acids through the inner cavity. Moreover, it was found that CsMRP4 mRNA was more abundant in the metacercariae than in the adults. Mouse immune serum, generated against the CsMRP4-NBD1 (24.9 kDa fragment, localized CsMRP4 mainly in mesenchymal tissues and oral and ventral suckers of the metacercariae and the adults. Conclusions Our findings shed new light on MRPs and their homologs and provide a platform for further structural and functional investigations on the bile transporters and parasites’ survival.

Sub-grouping and sub-functionalization of the RIFIN multi-copy protein family

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Sonnhammer Erik L

2008-01-01

Full Text Available Abstract Background Parasitic protozoans possess many multicopy gene families which have central roles in parasite survival and virulence. The number and variability of members of these gene families often make it difficult to predict possible functions of the encoded proteins. The families of extra-cellular proteins that are exposed to a host immune response have been driven via immune selection to become antigenically variant, and thereby avoid immune recognition while maintaining protein function to establish a chronic infection. Results We have combined phylogenetic and function shift analyses to study the evolution of the RIFIN proteins, which are antigenically variant and are encoded by the largest multicopy gene family in Plasmodium falciparum. We show that this family can be subdivided into two major groups that we named A- and B-RIFIN proteins. This suggested sub-grouping is supported by a recently published study that showed that, despite the presence of the Plasmodium export (PEXEL motif in all RIFIN variants, proteins from each group have different cellular localizations during the intraerythrocytic life cycle of the parasite. In the present study we show that function shift analysis, a novel technique to predict functional divergence between sub-groups of a protein family, indicates that RIFINs have undergone neo- or sub-functionalization. Conclusion These results question the general trend of clustering large antigenically variant protein groups into homogenous families. Assigning functions to protein families requires their subdivision into meaningful groups such as we have shown for the RIFIN protein family. Using phylogenetic and function shift analysis methods, we identify new directions for the investigation of this broad and complex group of proteins.

Ectopic expression of X-linked lymphocyte-regulated protein pM1 renders tumor cells resistant to antitumor immunity.

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Kang, Tae Heung; Noh, Kyung Hee; Kim, Jin Hee; Bae, Hyun Cheol; Lin, Ken Y; Monie, Archana; Pai, Sara I; Hung, Chien-Fu; Wu, T-C; Kim, Tae Woo

2010-04-15

Tumor immune escape is a major obstacle in cancer immunotherapy, but the mechanisms involved remain poorly understood. We have previously developed an immune evasion tumor model using an in vivo immune selection strategy and revealed Akt-mediated immune resistance to antitumor immunity induced by various cancer immunotherapeutic agents. In the current study, we used microarray gene analysis to identify an Akt-activating candidate molecule overexpressed in immune-resistant tumors compared with parental tumors. X-linked lymphocyte-regulated protein pM1 (XLR) gene was the most upregulated in immune-resistant tumors compared with parental tumor cells. Furthermore, the retroviral transduction of XLR in parental tumor cells led to activation of Akt, resulting in upregulation of antiapoptotic proteins and the induction of immune resistance phenotype in parental tumor cells. In addition, we found that transduction of parental tumor cells with other homologous genes from the mouse XLR family, such as synaptonemal complex protein 3 (SCP3) and XLR-related, meiosis-regulated protein (XMR) and its human counterpart of SCP3 (hSCP3), also led to activation of Akt, resulting in the upregulation of antiapoptotic proteins and induction of immune resistance phenotype. Importantly, characterization of a panel of human cervical cancers revealed relatively higher expression levels of hSCP3 in human cervical cancer tissue compared with normal cervical tissue. Thus, our data indicate that ectopic expression of XLR and its homologues in tumor cells represents a potentially important mechanism for tumor immune evasion and serves as a promising molecular target for cancer immunotherapy. (c) 2010 AACR.

MHC polymorphism and disease resistance to vibrio anguillarum in 8 families of half-smooth tongue sole (Cynoglossus semilaevis

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Liu Yan-hong

2011-09-01

Full Text Available Abstract Background Genes in the major histocompatibility complex (MHC have a critical role in both the innate and adaptive immune responses because of their involvement in presenting foreign peptides to T cells. However, the nature has remained largely unknown. Results We examined the genetic variation in MHC class IIB in half-smooth tongue sole (Cynoglossus semilaevis after challenge with vibrio anguillarum. Two thousand and four hundred fry from 12 half-smooth tongue sole families were challenged with Vibrio anguillarum. To determine any association between alleles and resistance or susceptibility to V. anguillarum, 160 individuals from four high-resistance (HR, 73.27% mortality families were selected for MHC IIB exon2 gene sequence analysis. The MHC IIB exon2 genes of tongue sole displayed a high level of polymorphism and were discovered at least four loci. Meanwhile, the dN/dS [the ratio of non-synonymous (dN substitutions to synonymous (dS substitutions] in the peptide-binding region (PBR was higher than that in the non-peptide-binding region (non-PBR. Eighty-eight alleles were discovered among 160 individuals, and 13 out of 88 alleles were used to analyze the distribution pattern between the resistant and susceptible families. Certain alleles presented in HR and LR with a different frequency, while other alleles were discovered in only the HR or LR families, not both. Five alleles, Cyse-DBB*6501, Cyse-DBB*4002, Cyse-DBB*6102, Cyse-DBB*5601 and Cyse-DBB*2801, were found to be associated with susceptibility to V. anguillarum with a frequency of 1.25%, 1.25%, 1.25%, 1.25% and 2.5% in the HR families, and 35%, 33.75%, 27.5%, 16.25%, 15% in the LR families (p Cyse-DBB*3301, Cyse-DBB*4701, Cyse-DBB*6801 and Cyse-DBB*5901, were found to be associated with resistance to V. anguillarum, with a frequency of 13.75%, 11.25%, 11.25%, 8.75% in the HR families and 1.25%, 1.25%, 1.25%, 1.25% and 1.25% in the LR families (p Conclusions Elucidation of the

CaMKII-MEDIATED PHOSPHORYLATION OF THE BOMBYX MORI LIPID STORAGE DROPLET PROTEIN-1 (BmLsd1), AN INSECT PAT FAMILY PROTEIN, IS ESSENTIAL FOR SILKMOTH SEX PHEROMONE BIOSYNTHESIS

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The structurally-related members of the PAT family of proteins, which are so name based on similarity amongst perilipin, adipophilin/adipocyte differentiation-related protein (ADRP), and tail-interacting protein of 47 kilodaltons (TIP47), are cytoplasmic lipid droplet (LD)-associated proteins charac...

Automatic discovery of cross-family sequence features associated with protein function

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Krings Andrea

2006-01-01

Full Text Available Abstract Background Methods for predicting protein function directly from amino acid sequences are useful tools in the study of uncharacterised protein families and in comparative genomics. Until now, this problem has been approached using machine learning techniques that attempt to predict membership, or otherwise, to predefined functional categories or subcellular locations. A potential drawback of this approach is that the human-designated functional classes may not accurately reflect the underlying biology, and consequently important sequence-to-function relationships may be missed. Results We show that a self-supervised data mining approach is able to find relationships between sequence features and functional annotations. No preconceived ideas about functional categories are required, and the training data is simply a set of protein sequences and their UniProt/Swiss-Prot annotations. The main technical aspect of the approach is the co-evolution of amino acid-based regular expressions and keyword-based logical expressions with genetic programming. Our experiments on a strictly non-redundant set of eukaryotic proteins reveal that the strongest and most easily detected sequence-to-function relationships are concerned with targeting to various cellular compartments, which is an area already well studied both experimentally and computationally. Of more interest are a number of broad functional roles which can also be correlated with sequence features. These include inhibition, biosynthesis, transcription and defence against bacteria. Despite substantial overlaps between these functions and their corresponding cellular compartments, we find clear differences in the sequence motifs used to predict some of these functions. For example, the presence of polyglutamine repeats appears to be linked more strongly to the "transcription" function than to the general "nuclear" function/location. Conclusion We have developed a novel and useful approach for

Ribosomal protein L3 mutations are associated with cfr-mediated linezolid resistance in clinical isolates of Staphylococcus cohnii.

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Xu, Hongtao; Tian, Rui; Li, Yanming; Chen, Dongke; Liu, Yalin; Hu, Yunjian; Xiao, Fei

2015-06-01

From June, 2012 to November, 2013 five linezolid-resistant Staphylococcus cohnii isolates were identified in our hospital in Beijing, China. The investigation of the resistance mechanisms confirmed that the cfr-carrying plasmids were the main cause of linezolid resistance in those clinical isolates. Moreover, all the five isolates had ribosomal protein L3 mutations, which had different coordinate effect on cfr-mediated linezolid resistance directly through the substitution of serine 158 by phenylalanine or tyrosine in L3 protein. In this study, two types of plasmids (p432, p438) (Accession No. KM114207) were found, which share high sequence identity with previously reported cfr-carrying pRM01 and pMHZ plasmids originated from northern and southern China, showing wide regional dissemination in China. The stability of linezolid resistance was studied by passaging single colonies serially on antibiotic-free blood medium, which showed that the susceptible derivatives emerged until the passages 39-42 with the elimination of cfr-carrying plasmid. Thus the high stability of this plasmid may pose a risk for the transmission among patients or even cause an outbreak in clinical settings.

Regulation of Multidrug Resistance Proteins by Genistein in a Hepatocarcinoma Cell Line: Impact on Sorafenib Cytotoxicity

OpenAIRE

Rigalli, Juan Pablo; Ciriaci, Nadia; Arias, Agostina; Ceballos, Mar?a Paula; Villanueva, Silvina Stella Maris; Luquita, Marcelo Gabriel; Mottino, Aldo Domingo; Ghanem, Carolina In?s; Catania, Viviana Alicia; Ruiz, Mar?a Laura

2015-01-01

Hepatocellular carcinoma (HCC) is the fifth most frequent cancer worldwide. Sorafenib is the only drug available that improves the overall survival of HCC patients. P-glycoprotein (P-gp), Multidrug resistance-associated proteins 2 and 3 (MRP2 and 3) and Breast cancer resistance protein (BCRP) are efflux pumps that play a key role in cancer chemoresistance. Their modulation by dietary compounds may affect the intracellular accumulation and therapeutic efficacy of drugs that are substrates of t...

Mechanisms of resistance to HER family targeting antibodies

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Kruser, Tim J. [Department of Human Oncology, University of Wisconsin School of Medicine and Public Health, Madison, WI (United States); Wheeler, Deric L., E-mail: dlwheeler@wisc.edu [Department of Human Oncology, University of Wisconsin School of Medicine and Public Health, Madison, WI (United States)

2010-04-15

The epidermal growth factor (EGF) family of receptor tyrosine kinases consists of four members: EGFR (HER1/ErbB1), HER2/neu (ErbB2), HER3 (ErbB3) and HER4 (ErbB4). Receptor activation via ligand binding leads to downstream signaling that influence cell proliferation, angiogenesis, invasion and metastasis. Aberrant expression or activity of EGFR and HER2 have been strongly linked to the etiology of several human epithelial cancers including but not limited to head and neck squamous cell carcinoma (HNSCC), non-small cell lung cancer (NSCLC), colorectal cancer (CRC), and breast cancer. With this, intense efforts have been made to inhibit the activity of the EGFR and HER2 by designing antibodies against the ligand binding domains (cetuximab, panitumumab and trastuzumab) or small molecules against the tyrosine kinase domains (erlotinib, gefitinib, and lapatinib). Both approaches have shown considerable clinical promise. However, increasing evidence suggests that the majority of patients do not respond to these therapies, and those who show initial response ultimately become refractory to treatment. While mechanisms of resistance to tyrosine kinase inhibitors have been extensively studied, resistance to monoclonal antibodies is less well understood, both in the laboratory and in the clinical setting. In this review, we discuss resistance to antibody-based therapies against the EGFR and HER2, similarities between these resistance profiles, and strategies to overcome resistance to HER family targeting monoclonal antibody therapy.

Structure of Rhodococcus equi virulence-associated protein B (VapB) reveals an eight-stranded antiparallel β-barrel consisting of two Greek-key motifs

International Nuclear Information System (INIS)

Geerds, Christina; Wohlmann, Jens; Haas, Albert; Niemann, Hartmut H.

2014-01-01

The structure of VapB, a member of the Vap protein family that is involved in virulence of the bacterial pathogen R. equi, was determined by SAD phasing and reveals an eight-stranded antiparallel β-barrel similar to avidin, suggestive of a binding function. Made up of two Greek-key motifs, the topology of VapB is unusual or even unique. Members of the virulence-associated protein (Vap) family from the pathogen Rhodococcus equi regulate virulence in an unknown manner. They do not share recognizable sequence homology with any protein of known structure. VapB and VapA are normally associated with isolates from pigs and horses, respectively. To contribute to a molecular understanding of Vap function, the crystal structure of a protease-resistant VapB fragment was determined at 1.4 Å resolution. The structure was solved by SAD phasing employing the anomalous signal of one endogenous S atom and two bound Co ions with low occupancy. VapB is an eight-stranded antiparallel β-barrel with a single helix. Structural similarity to avidins suggests a potential binding function. Unlike other eight- or ten-stranded β-barrels found in avidins, bacterial outer membrane proteins, fatty-acid-binding proteins and lysozyme inhibitors, Vaps do not have a next-neighbour arrangement but consist of two Greek-key motifs with strand order 41238567, suggesting an unusual or even unique topology

Structure of Rhodococcus equi virulence-associated protein B (VapB) reveals an eight-stranded antiparallel β-barrel consisting of two Greek-key motifs

Energy Technology Data Exchange (ETDEWEB)

Geerds, Christina [Bielefeld University, Universitaetsstrasse 25, 33615 Bielefeld (Germany); Wohlmann, Jens; Haas, Albert [University of Bonn, Ulrich-Haberland Strasse 61a, 53121 Bonn (Germany); Niemann, Hartmut H., E-mail: hartmut.niemann@uni-bielefeld.de [Bielefeld University, Universitaetsstrasse 25, 33615 Bielefeld (Germany)

2014-06-18

The structure of VapB, a member of the Vap protein family that is involved in virulence of the bacterial pathogen R. equi, was determined by SAD phasing and reveals an eight-stranded antiparallel β-barrel similar to avidin, suggestive of a binding function. Made up of two Greek-key motifs, the topology of VapB is unusual or even unique. Members of the virulence-associated protein (Vap) family from the pathogen Rhodococcus equi regulate virulence in an unknown manner. They do not share recognizable sequence homology with any protein of known structure. VapB and VapA are normally associated with isolates from pigs and horses, respectively. To contribute to a molecular understanding of Vap function, the crystal structure of a protease-resistant VapB fragment was determined at 1.4 Å resolution. The structure was solved by SAD phasing employing the anomalous signal of one endogenous S atom and two bound Co ions with low occupancy. VapB is an eight-stranded antiparallel β-barrel with a single helix. Structural similarity to avidins suggests a potential binding function. Unlike other eight- or ten-stranded β-barrels found in avidins, bacterial outer membrane proteins, fatty-acid-binding proteins and lysozyme inhibitors, Vaps do not have a next-neighbour arrangement but consist of two Greek-key motifs with strand order 41238567, suggesting an unusual or even unique topology.

CD44 Promotes intoxication by the clostridial iota-family toxins.

Science.gov (United States)

Wigelsworth, Darran J; Ruthel, Gordon; Schnell, Leonie; Herrlich, Peter; Blonder, Josip; Veenstra, Timothy D; Carman, Robert J; Wilkins, Tracy D; Van Nhieu, Guy Tran; Pauillac, Serge; Gibert, Maryse; Sauvonnet, Nathalie; Stiles, Bradley G; Popoff, Michel R; Barth, Holger

2012-01-01

Various pathogenic clostridia produce binary protein toxins associated with enteric diseases of humans and animals. Separate binding/translocation (B) components bind to a protein receptor on the cell surface, assemble with enzymatic (A) component(s), and mediate endocytosis of the toxin complex. Ultimately there is translocation of A component(s) from acidified endosomes into the cytosol, leading to destruction of the actin cytoskeleton. Our results revealed that CD44, a multifunctional surface protein of mammalian cells, facilitates intoxication by the iota family of clostridial binary toxins. Specific antibody against CD44 inhibited cytotoxicity of the prototypical Clostridium perfringens iota toxin. Versus CD44(+) melanoma cells, those lacking CD44 bound less toxin and were dose-dependently resistant to C. perfringens iota, as well as Clostridium difficile and Clostridium spiroforme iota-like, toxins. Purified CD44 specifically interacted in vitro with iota and iota-like, but not related Clostridium botulinum C2, toxins. Furthermore, CD44 knockout mice were resistant to iota toxin lethality. Collective data reveal an important role for CD44 during intoxication by a family of clostridial binary toxins.

The Pentapeptide Repeat Proteins

OpenAIRE

Vetting, Matthew W.; Hegde, Subray S.; Fajardo, J. Eduardo; Fiser, Andras; Roderick, Steven L.; Takiff, Howard E.; Blanchard, John S.

2006-01-01

The Pentapeptide Repeat Protein (PRP) family has over 500 members in the prokaryotic and eukaryotic kingdoms. These proteins are composed of, or contain domains composed of, tandemly repeated amino acid sequences with a consensus sequence of [S,T,A,V][D,N][L,F]-[S,T,R][G]. The biochemical function of the vast majority of PRP family members is unknown. The three-dimensional structure of the first member of the PRP family was determined for the fluoroquinolone resistance protein (MfpA) from Myc...

Localization of multidrug resistance-associated protein 2 in the nonpigmented ciliary epithelium of the eye.

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Pelis, Ryan M; Shahidullah, Mohammad; Ghosh, Sikha; Coca-Prados, Miguel; Wright, Stephen H; Delamere, Nicholas A

2009-05-01

The nonpigmented epithelium (NPE) of the ciliary body represents an important component of the blood-aqueous barrier of the eye. Many therapeutic drugs penetrate poorly across the NPE into the aqueous humor of the eye interior. Several of these therapeutic drugs, such as methotrexate, vincristine, and etoposide, are substrates of the multidrug resistance-associated protein 2 (MRP2). Abundant MRP2 protein was detected by Western blot in homogenates of human ciliary body and freshly dissected porcine NPE. In cultured porcine NPE, the intracellular accumulation of the MRP2 substrates calcein (1.8-fold), 5-(and-6)-carboxy-2',7'-dichlorofluorescein (22.1-fold), and doxorubicin (1.9-fold) was significantly increased in the presence of 50 microM MK571 ((E)-3-[[[3-[2-(7-chloro-2-quinolinyl)-ethenyl]phenyl]-[[3-dimethylamino)-3-oxopropyl]thio]methyl]thio]-propanoic acid), an MRP inhibitor. In addition, the intracellular accumulation of the MRP2 substrate glutathione methylfluorescein was increased by 50 microM MK571 (4.3-fold), 500 microM indomethacin (2.6-fold), and 50 microM cyclosporin A (2.1-fold) but not by 500 microM sulfinpyrazone. These data are consistent with MRP2-mediated transport activity in cultured NPE, and MRP2 mRNA (reverse transcriptase-polymerase chain reaction) and protein (Western blot) were detected in the cultured cells. Immunolocalization studies in native human and porcine eyes showed MRP2 protein at the apical interface of the NPE and pigmented cell layers. Close examination of MRP2 immunoreactivity supported the conclusion that MRP2 is localized in the apical membrane of the NPE. MRP2 at the apical membrane of NPE cells may be involved in protecting intraocular tissues from exposure to potentially harmful toxins.

F-BAR family proteins, emerging regulators for cell membrane dynamic changes-from structure to human diseases.

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Liu, Suxuan; Xiong, Xinyu; Zhao, Xianxian; Yang, Xiaofeng; Wang, Hong

2015-05-09

Eukaryotic cell membrane dynamics change in curvature during physiological and pathological processes. In the past ten years, a novel protein family, Fes/CIP4 homology-Bin/Amphiphysin/Rvs (F-BAR) domain proteins, has been identified to be the most important coordinators in membrane curvature regulation. The F-BAR domain family is a member of the Bin/Amphiphysin/Rvs (BAR) domain superfamily that is associated with dynamic changes in cell membrane. However, the molecular basis in membrane structure regulation and the biological functions of F-BAR protein are unclear. The pathophysiological role of F-BAR protein is unknown. This review summarizes the current understanding of structure and function in the BAR domain superfamily, classifies F-BAR family proteins into nine subfamilies based on domain structure, and characterizes F-BAR protein structure, domain interaction, and functional relevance. In general, F-BAR protein binds to cell membrane via F-BAR domain association with membrane phospholipids and initiates membrane curvature and scission via Src homology-3 (SH3) domain interaction with its partner proteins. This process causes membrane dynamic changes and leads to seven important cellular biological functions, which include endocytosis, phagocytosis, filopodium, lamellipodium, cytokinesis, adhesion, and podosome formation, via distinct signaling pathways determined by specific domain-binding partners. These cellular functions play important roles in many physiological and pathophysiological processes. We further summarize F-BAR protein expression and mutation changes observed in various diseases and developmental disorders. Considering the structure feature and functional implication of F-BAR proteins, we anticipate that F-BAR proteins modulate physiological and pathophysiological processes via transferring extracellular materials, regulating cell trafficking and mobility, presenting antigens, mediating extracellular matrix degradation, and transmitting

Genetic dissection of powdery mildew resistance in interspecific half-sib grapevine families using SNP-based maps.

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Teh, Soon Li; Fresnedo-Ramírez, Jonathan; Clark, Matthew D; Gadoury, David M; Sun, Qi; Cadle-Davidson, Lance; Luby, James J

2017-01-01

Quantitative trait locus (QTL) identification in perennial fruit crops is impeded largely by their lengthy generation time, resulting in costly and labor-intensive maintenance of breeding programs. In a grapevine (genus Vitis ) breeding program, although experimental families are typically unreplicated, the genetic backgrounds may contain similar progenitors previously selected due to their contribution of favorable alleles. In this study, we investigated the utility of joint QTL identification provided by analyzing half-sib families. The genetic control of powdery mildew was studied using two half-sib F 1 families, namely GE0711/1009 (MN1264 × MN1214; N  = 147) and GE1025 (MN1264 × MN1246; N  = 125) with multiple species in their ancestry. Maternal genetic maps consisting of 1077 and 1641 single nucleotide polymorphism (SNP) markers, respectively, were constructed using a pseudo-testcross strategy. Ratings of field resistance to powdery mildew were obtained based on whole-plant evaluation of disease severity. This 2-year analysis uncovered two QTLs that were validated on a consensus map in these half-sib families with improved precision relative to the parental maps. Examination of haplotype combinations based on the two QTL regions identified strong association of haplotypes inherited from 'Seyval blanc', through MN1264, with powdery mildew resistance. This investigation also encompassed the use of microsatellite markers to establish a correlation between 206-bp (UDV-015b) and 357-bp (VViv67) fragment sizes with resistance-carrying haplotypes. Our work is one of the first reports in grapevine demonstrating the use of SNP-based maps and haplotypes for QTL identification and tagging of powdery mildew resistance in half-sib families.

PATtyFams: Protein families for the microbial genomes in the PATRIC database

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James J Davis

2016-02-01

Full Text Available The ability to build accurate protein families is a fundamental operation in bioinformatics that influences comparative analyses, genome annotation and metabolic modeling. For several years we have been maintaining protein families for all microbial genomes in the PATRIC database (Pathosystems Resource Integration Center, patricbrc.org in order to drive many of the comparative analysis tools that are available through the PATRIC website. However, due to the burgeoning number of genomes, traditional approaches for generating protein families are becoming prohibitive. In this report, we describe a new approach for generating protein families, which we call PATtyFams. This method uses the k-mer-based function assignments available through RAST (Rapid Annotation using Subsystem Technology to rapidly guide family formation, and then differentiates the function-based groups into families using a Markov Cluster algorithm (MCL. This new approach for generating protein families is rapid, scalable and has properties that are consistent with alignment-based methods.

The netrin protein family.

Science.gov (United States)

Rajasekharan, Sathyanath; Kennedy, Timothy E

2009-01-01

The name netrin is derived from the Sanskrit Netr, meaning 'guide'. Netrins are a family of extracellular proteins that direct cell and axon migration during embryogenesis. Three secreted netrins (netrins 1, 3 and 4), and two glycosylphosphatidylinositol (GPI)-anchored membrane proteins, netrins G1 and G2, have been identified in mammals. The secreted netrins are bifunctional, acting as attractants for some cell types and repellents for others. Receptors for the secreted netrins include the Deleted in Colorectal Cancer (DCC) family, the Down's syndrome cell adhesion molecule (DSCAM), and the UNC-5 homolog family: Unc5A, B, C and D in mammals. Netrin Gs do not appear to interact with these receptors, but regulate synaptic interactions between neurons by binding to the transmembrane netrin G ligands NGL1 and 2. The chemotropic function of secreted netrins has been best characterized with regard to axon guidance during the development of the nervous system. Extending axons are tipped by a flattened, membranous structure called the growth cone. Multiple extracellular guidance cues direct axonal growth cones to their ultimate targets where synapses form. Such cues can be locally derived (short-range), or can be secreted diffusible cues that allow target cells to signal axons from a distance (long-range). The secreted netrins function as short-range and long-range guidance cues in different circumstances. In addition to directing cell migration, functional roles for netrins have been identified in the regulation of cell adhesion, the maturation of cell morphology, cell survival and tumorigenesis.

Drug efflux proteins in multidrug resistant bacteria

NARCIS (Netherlands)

vanVeen, HW; Konings, WN

Bacteria contain an array of transport proteins in their cytoplasmic membrane. Many of these proteins play an important role in conferring resistance to toxic compounds. The multidrug efflux systems encountered in prokaryotic cells are very similar to those observed in eukaryotic cells. Therefore, a

Analysis of substructural variation in families of enzymatic proteins with applications to protein function prediction

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Fofanov Viacheslav Y

2010-05-01

Full Text Available Abstract Background Structural variations caused by a wide range of physico-chemical and biological sources directly influence the function of a protein. For enzymatic proteins, the structure and chemistry of the catalytic binding site residues can be loosely defined as a substructure of the protein. Comparative analysis of drug-receptor substructures across and within species has been used for lead evaluation. Substructure-level similarity between the binding sites of functionally similar proteins has also been used to identify instances of convergent evolution among proteins. In functionally homologous protein families, shared chemistry and geometry at catalytic sites provide a common, local point of comparison among proteins that may differ significantly at the sequence, fold, or domain topology levels. Results This paper describes two key results that can be used separately or in combination for protein function analysis. The Family-wise Analysis of SubStructural Templates (FASST method uses all-against-all substructure comparison to determine Substructural Clusters (SCs. SCs characterize the binding site substructural variation within a protein family. In this paper we focus on examples of automatically determined SCs that can be linked to phylogenetic distance between family members, segregation by conformation, and organization by homology among convergent protein lineages. The Motif Ensemble Statistical Hypothesis (MESH framework constructs a representative motif for each protein cluster among the SCs determined by FASST to build motif ensembles that are shown through a series of function prediction experiments to improve the function prediction power of existing motifs. Conclusions FASST contributes a critical feedback and assessment step to existing binding site substructure identification methods and can be used for the thorough investigation of structure-function relationships. The application of MESH allows for an automated

Prevalence of Resistence to Activated Protein C (Apc-Resistance in Blood Donors in Kosovo

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Ymer Mekaj

2009-11-01

Full Text Available AbstractOne of the most frequent hereditary causes of thrombophilia is, without a doubt, resistance to Activated Protein C (APC-resistance, which is a consequence of point mutation in gene coding for coagulation Factor V (Factor V Leiden in 90-95% of cases.The aim of this paper was to determine prevalence of APC-resistance in a group of healthy blood donors. The size of the group is quite representative of Kosovo Albanians.A total of 944 blood donors were examined (537 males and 407 females, for whom APC-resistance was determined by functional methods of coagulation using the kit ACTICLOT® Protein C Resistance. Method is based on the test of APTT determined twice: first in the presence and second in the absence of activated Protein C (APC. The ratio of these two values constitutes is called Activated Protein C - Sensitivity Ratio (APC-SR.From 944 examined donors, pathologic values of APC-SR (1,3-1,9 were found in 32 persons (3,4% of the total number. The distribution among sexes was 3,35% (18/537 in male and 3,43% (14/407 in female subjects. The mean values of APC-SR (1,64 in male and 1,71 in female subjects were not significantly different (P = 0,22.Based on these results, we conclude that the prevalence of APC resistance in Albanian population of Kosovo is within the lower limit of prevalence in general population in different countries of European countries, which, according to some authors ranges is from 3 to 7%.

Pregnancy-associated polyuria in familial renal glycosuria.

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Toka, Hakan R; Yang, Jun; Zera, Chloe A; Duffield, Jeremy S; Pollak, Martin R; Mount, David B

2013-12-01

A pregnant woman presented at gestational week 28 with loss of consciousness and profound polyuria. Further characterization revealed osmotic diuresis due to massive glycosuria without hyperglycemia. Glycosuria reduced substantially postpartum, from approximately 100 to approximately 30 g/1.73 m2 per day. DNA sequencing analysis of the SLC5A2 gene encoding the renal glucose transporter SGLT2 showed a homozygous frame-shift mutation (occurring after the glutamine at amino acid 168 and leading to premature termination of the protein at amino acid 186) diagnostic of familial renal glycosuria. Pregnant women with familial renal glycosuria can be at risk of profound polyuria during pregnancy due to the associated increase in glycosuria. These findings also have implications for the use of SGLT2 inhibitors in clinical practice. Published by Elsevier Inc.

Dietary protein to maximize resistance training: a review and examination of protein spread and change theories.

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Bosse, John D; Dixon, Brian M

2012-09-08

An appreciable volume of human clinical data supports increased dietary protein for greater gains from resistance training, but not all findings are in agreement. We recently proposed "protein spread theory" and "protein change theory" in an effort to explain discrepancies in the response to increased dietary protein in weight management interventions. The present review aimed to extend "protein spread theory" and "protein change theory" to studies examining the effects of protein on resistance training induced muscle and strength gains. Protein spread theory proposed that there must have been a sufficient spread or % difference in g/kg/day protein intake between groups during a protein intervention to see muscle and strength differences. Protein change theory postulated that for the higher protein group, there must be a sufficient change from baseline g/kg/day protein intake to during study g/kg/day protein intake to see muscle and strength benefits. Seventeen studies met inclusion criteria. In studies where a higher protein intervention was deemed successful there was, on average, a 66.1% g/kg/day between group intake spread versus a 10.2% g/kg/day spread in studies where a higher protein diet was no more effective than control. The average change in habitual protein intake in studies showing higher protein to be more effective than control was +59.5% compared to +6.5% when additional protein was no more effective than control. The magnitudes of difference between the mean spreads and changes of the present review are similar to our previous review on these theories in a weight management context. Providing sufficient deviation from habitual intake appears to be an important factor in determining the success of additional protein in enhancing muscle and strength gains from resistance training. An increase in dietary protein favorably effects muscle and strength during resistance training.

The tumor necrosis factor-alpha-induced protein 8 family in immune homeostasis and inflammatory cancer diseases.

Science.gov (United States)

Luan, Y Y; Yao, Y M; Sheng, Z Y

2013-01-01

Within the immune system homeostasis is maintained by a myriad of mechanisms that include the regulation of immune cell activation and programmed cell death. The breakdown of immune homeostasis may lead to fatal inflammatory diseases. We set out to identify genes of tumor necrosis factor-alpha-induced protein 8 (TNFAIP8) family that has a functional role in the process of immune homeostasis. Tumor necrosis factor-alpha-induced protein 8 (TNFAIP8), which functions as an oncogenic molecule, is also associated with enhanced cell survival and inhibition of apoptosis. Tumor necrosis factor-alpha-induced protein 8-like 2 (TIPE2) governs immune homeostasis in both the innate and adaptive immune system and prevents hyper-responsiveness by negatively regulating signaling via T cell receptors and Toll-like receptors (TLRs). There also exist two highly homologous but uncharacterized proteins, TIPE1 and TIPE3. This review is an attempt to provide a summary of TNFAIP8 family associated with immune homeostasis and inflammatory cancer diseases.

DAZ Family Proteins, Key Players for Germ Cell Development

Science.gov (United States)

Fu, Xia-Fei; Cheng, Shun-Feng; Wang, Lin-Qing; Yin, Shen; De Felici, Massimo; Shen, Wei

2015-01-01

DAZ family proteins are found almost exclusively in germ cells in distant animal species. Deletion or mutations of their encoding genes usually severely impair either oogenesis or spermatogenesis or both. The family includes Boule (or Boll), Dazl (or Dazla) and DAZ genes. Boule and Dazl are situated on autosomes while DAZ, exclusive of higher primates, is located on the Y chromosome. Deletion of DAZ gene is the most common causes of infertility in humans. These genes, encoding for RNA binding proteins, contain a highly conserved RNA recognition motif and at least one DAZ repeat encoding for a 24 amino acids sequence able to bind other mRNA binding proteins. Basically, Daz family proteins function as adaptors for target mRNA transport and activators of their translation. In some invertebrate species, BOULE protein play a pivotal role in germline specification and a conserved regulatory role in meiosis. Depending on the species, DAZL is expressed in primordial germ cells (PGCs) and/or pre-meiotic and meiotic germ cells of both sexes. Daz is found in fetal gonocytes, spermatogonia and spermatocytes of adult testes. Here we discuss DAZ family genes in a phylogenic perspective, focusing on the common and distinct features of these genes, and their pivotal roles during gametogenesis evolved during evolution. PMID:26327816

Two members of TaRLK family confer powdery mildew resistance in common wheat.

Science.gov (United States)

Chen, Tingting; Xiao, Jin; Xu, Jun; Wan, Wentao; Qin, Bi; Cao, Aizhong; Chen, Wei; Xing, Liping; Du, Chen; Gao, Xiquan; Zhang, Shouzhong; Zhang, Ruiqi; Shen, Wenbiao; Wang, Haiyan; Wang, Xiue

2016-01-25

Powdery mildew, caused by Blumeria graminearum f.sp. tritici (Bgt), is one of the most severe fungal diseases of wheat. The exploration and utilization of new gene resources is the most effective approach for the powdery mildew control. We report the cloning and functional analysis of two wheat LRR-RLKs from T. aestivum c.v. Prins- T. timopheevii introgression line IGV1-465, named TaRLK1 and TaRLK2, which play positive roles in regulating powdery mildew resistance in wheat. The two LRR-RLKs contain an ORF of 3,045 nucleotides, encoding a peptide of 1014 amino acids, with seven amino acids difference. Their predicted proteins possess a signal peptide, several LRRs, a trans-membrane domain, and a Ser/Thr protein kinase domain. In response to Bgt infection, the TaRLK1/2 expression is up-regulated in a developmental-stage-dependent manner. Single-cell transient over-expression and gene-silencing assays indicate that both genes positively regulate the resistance to mixed Bgt inoculums. Transgenic lines over-expressing TaRLK1 or TaRLK2 in a moderate powdery mildew susceptible wheat variety Yangmai 158 led to significantly enhanced powdery mildew resistance. Exogenous applied salicylic acid (SA) or hydrogen peroxide (H2O2) induced the expression of both genes, and H2O2 had a higher accumulation at the Bgt penetration sites in RLK over-expression transgenic plants, suggesting a possible involvement of SA and altered ROS homeostasis in the defense response to Bgt infection. The two LRR-RLKs are located in the long arm of wheat chromosome 2B, in which the powdery mildew resistance gene Pm6 is located, but in different regions. Two members of TaRLK family were cloned from IGV1-465. TaRLK1 and TaRLK2 contribute to powdery mildew resistance of wheat, providing new resistance gene resources for wheat breeding.

Mechanism of the pharmacokinetic interaction between methotrexate and benzimidazoles: potential role for breast cancer resistance protein in clinical drug-drug interactions

NARCIS (Netherlands)

Breedveld, Pauline; Zelcer, Noam; Pluim, Dick; Sönmezer, Ozgür; Tibben, Matthijs M.; Beijnen, Jos H.; Schinkel, Alfred H.; van Tellingen, Olaf; Borst, Piet; Schellens, Jan H. M.

2004-01-01

The antifolate drug methotrexate (MTX) is transported by breast cancer resistance protein (BCRP; ABCG2) and multidrug resistance-associated protein1-4 (MRP1-4; ABCC1-4). In cancer patients, coadministration of benzimidazoles and MTX can result in profound MTX-induced toxicity coinciding with an

Variability and action mechanism of a family of anticomplement proteins in Ixodes ricinus.

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Bernard Couvreur

Full Text Available BACKGROUND: Ticks are blood feeding arachnids that characteristically take a long blood meal. They must therefore counteract host defence mechanisms such as hemostasis, inflammation and the immune response. This is achieved by expressing batteries of salivary proteins coded by multigene families. METHODOLOGY/PRINCIPAL FINDINGS: We report the in-depth analysis of a tick multigene family and describe five new anticomplement proteins in Ixodes ricinus. Compared to previously described Ixodes anticomplement proteins, these segregated into a new phylogenetic group or subfamily. These proteins have a novel action mechanism as they specifically bind to properdin, leading to the inhibition of C3 convertase and the alternative complement pathway. An excess of non-synonymous over synonymous changes indicated that coding sequences had undergone diversifying selection. Diversification was not associated with structural, biochemical or functional diversity, adaptation to host species or stage specificity but rather to differences in antigenicity. CONCLUSIONS/SIGNIFICANCE: Anticomplement proteins from I. ricinus are the first inhibitors that specifically target a positive regulator of complement, properdin. They may provide new tools for the investigation of role of properdin in physiological and pathophysiological mechanisms. They may also be useful in disorders affecting the alternative complement pathway. Looking for and detecting the different selection pressures involved will help in understanding the evolution of multigene families and hematophagy in arthropods.

Supplementary Material for: Mycobacterium tuberculosis whole genome sequencing and protein structure modelling provides insights into anti-tuberculosis drug resistance

KAUST Repository

Phelan, Jody; Coll, Francesc; McNerney, Ruth; Ascher, David; Pires, Douglas; Furnham, Nick; Coeck, Nele; Hill-Cawthorne, Grant; Nair, Mridul; Mallard, Kim; Ramsay, Andrew; Campino, Susana; Hibberd, Martin; Pain, Arnab; Rigouts, Leen; Clark, Taane

2016-01-01

Abstract Background Combating the spread of drug resistant tuberculosis is a global health priority. Whole genome association studies are being applied to identify genetic determinants of resistance to anti-tuberculosis drugs. Protein structure

HIPPI: highly accurate protein family classification with ensembles of HMMs

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Nam-phuong Nguyen

2016-11-01

Full Text Available Abstract Background Given a new biological sequence, detecting membership in a known family is a basic step in many bioinformatics analyses, with applications to protein structure and function prediction and metagenomic taxon identification and abundance profiling, among others. Yet family identification of sequences that are distantly related to sequences in public databases or that are fragmentary remains one of the more difficult analytical problems in bioinformatics. Results We present a new technique for family identification called HIPPI (Hierarchical Profile Hidden Markov Models for Protein family Identification. HIPPI uses a novel technique to represent a multiple sequence alignment for a given protein family or superfamily by an ensemble of profile hidden Markov models computed using HMMER. An evaluation of HIPPI on the Pfam database shows that HIPPI has better overall precision and recall than blastp, HMMER, and pipelines based on HHsearch, and maintains good accuracy even for fragmentary query sequences and for protein families with low average pairwise sequence identity, both conditions where other methods degrade in accuracy. Conclusion HIPPI provides accurate protein family identification and is robust to difficult model conditions. Our results, combined with observations from previous studies, show that ensembles of profile Hidden Markov models can better represent multiple sequence alignments than a single profile Hidden Markov model, and thus can improve downstream analyses for various bioinformatic tasks. Further research is needed to determine the best practices for building the ensemble of profile Hidden Markov models. HIPPI is available on GitHub at https://github.com/smirarab/sepp .

[Interconnection between architecture of protein globule and disposition of conformational conservative oligopeptides in proteins from one protein family].

Science.gov (United States)

Batianovskiĭ, A V; Filatov, I V; Namiot, V A; Esipova, N G; Volotovskiĭ, I D

2012-01-01

It was shown that selective interactions between helical segments of macromolecules can realize in globular proteins in the segments characterized by the same periodicities of charge distribution i.e. between conformationally conservative oligopeptides. It was found that in the macromolecules of alpha-helical proteins conformationally conservative oligopeptides are disposed at a distance being characteristic of direct interactions. For representatives of many structural families of alpha-type proteins specific disposition of conformationally conservative segments is observed. This disposition is inherent to a particular structural family. Disposition of conformationally conservative segments is not related to homology of the amino acid sequence but reflects peculiarities of native 3D-architectures of protein globules.

Evolutionary hierarchy of vertebrate-like heterotrimeric G protein families.

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Krishnan, Arunkumar; Mustafa, Arshi; Almén, Markus Sällman; Fredriksson, Robert; Williams, Michael J; Schiöth, Helgi B

2015-10-01

Heterotrimeric G proteins perform a crucial role as molecular switches controlling various cellular responses mediated by G protein-coupled receptor (GPCR) signaling pathway. Recent data have shown that the vertebrate-like G protein families are found across metazoans and their closest unicellular relatives. However, an overall evolutionary hierarchy of vertebrate-like G proteins, including gene family annotations and in particular mapping individual gene gain/loss events across diverse holozoan lineages is still incomplete. Here, with more expanded invertebrate taxon sampling, we have reconstructed phylogenetic trees for each of the G protein classes/families and provide a robust classification and hierarchy of vertebrate-like heterotrimeric G proteins. Our results further extend the evidence that the common ancestor (CA) of holozoans had at least five ancestral Gα genes corresponding to all major vertebrate Gα classes and contain a total of eight genes including two Gβ and one Gγ. Our results also indicate that the GNAI/O-like gene likely duplicated in the last CA of metazoans to give rise to GNAI- and GNAO-like genes, which are conserved across invertebrates. Moreover, homologs of GNB1-4 paralogon- and GNB5 family-like genes are found in most metazoans and that the unicellular holozoans encode two ancestral Gβ genes. Similarly, most bilaterian invertebrates encode two Gγ genes which include a representative of the GNG gene cluster and a putative homolog of GNG13. Interestingly, our results also revealed key evolutionary events such as the Drosophila melanogaster eye specific Gβ subunit that is found conserved in most arthropods and several previously unidentified species specific expansions within Gαi/o, Gαs, Gαq, Gα12/13 classes and the GNB1-4 paralogon. Also, we provide an overall proposed evolutionary scenario on the expansions of all G protein families in vertebrate tetraploidizations. Our robust classification/hierarchy is essential to further

Identification of genetic markers linked to anthracnose resistance in sorghum using association analysis.

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Upadhyaya, Hari D; Wang, Yi-Hong; Sharma, Rajan; Sharma, Shivali

2013-06-01

Anthracnose in sorghum caused by Colletotrichum sublineolum is one of the most destructive diseases affecting sorghum production under warm and humid conditions. Markers and genes linked to resistance to the disease are important for plant breeding. Using 14,739 SNP markers, we have mapped eight loci linked to resistance in sorghum through association analysis of a sorghum mini-core collection consisting of 242 diverse accessions evaluated for anthracnose resistance for 2 years in the field. The mini-core was representative of the International Crops Research Institute for the Semi-Arid Tropics' world-wide sorghum landrace collection. Eight marker loci were associated with anthracnose resistance in both years. Except locus 8, disease resistance-related genes were found in all loci based on their physical distance from linked SNP markers. These include two NB-ARC class of R genes on chromosome 10 that were partially homologous to the rice blast resistance gene Pib, two hypersensitive response-related genes: autophagy-related protein 3 on chromosome 1 and 4 harpin-induced 1 (Hin1) homologs on chromosome 8, a RAV transcription factor that is also part of R gene pathway, an oxysterol-binding protein that functions in the non-specific host resistance, and homologs of menthone:neomenthol reductase (MNR) that catalyzes a menthone reduction to produce the antimicrobial neomenthol. These genes and markers may be developed into molecular tools for genetic improvement of anthracnose resistance in sorghum.

Whole-genome sequencing reveals the mechanisms for evolution of streptomycin resistance in Lactobacillus plantarum.

Science.gov (United States)

Zhang, Fuxin; Gao, Jiayuan; Wang, Bini; Huo, Dongxue; Wang, Zhaoxia; Zhang, Jiachao; Shao, Yuyu

2018-04-01

In this research, we investigated the evolution of streptomycin resistance in Lactobacillus plantarum ATCC14917, which was passaged in medium containing a gradually increasing concentration of streptomycin. After 25 d, the minimum inhibitory concentration (MIC) of L. plantarum ATCC14917 had reached 131,072 µg/mL, which was 8,192-fold higher than the MIC of the original parent isolate. The highly resistant L. plantarum ATCC14917 isolate was then passaged in antibiotic-free medium to determine the stability of resistance. The MIC value of the L. plantarum ATCC14917 isolate decreased to 2,048 µg/mL after 35 d but remained constant thereafter, indicating that resistance was irreversible even in the absence of selection pressure. Whole-genome sequencing of parent isolates, control isolates, and isolates following passage was used to study the resistance mechanism of L. plantarum ATCC14917 to streptomycin and adaptation in the presence and absence of selection pressure. Five mutated genes (single nucleotide polymorphisms and structural variants) were verified in highly resistant L. plantarum ATCC14917 isolates, which were related to ribosomal protein S12, LPXTG-motif cell wall anchor domain protein, LrgA family protein, Ser/Thr phosphatase family protein, and a hypothetical protein that may correlate with resistance to streptomycin. After passage in streptomycin-free medium, only the mutant gene encoding ribosomal protein S12 remained; the other 4 mutant genes had reverted to the wild type as found in the parent isolate. Although the MIC value of L. plantarum ATCC14917 was reduced in the absence of selection pressure, it remained 128-fold higher than the MIC value of the parent isolate, indicating that ribosomal protein S12 may play an important role in streptomycin resistance. Using the mobile elements database, we demonstrated that streptomycin resistance-related genes in L. plantarum ATCC14917 were not located on mobile elements. This research offers a way of

The sensitivity of diffuse large B-cell lymphoma cell lines to histone deacetylase inhibitor-induced apoptosis is modulated by BCL-2 family protein activity.

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Ryan C Thompson

Full Text Available BACKGROUND: Diffuse large B-cell lymphoma (DLBCL is a genetically heterogeneous disease and this variation can often be used to explain the response of individual patients to chemotherapy. One cancer therapeutic approach currently in clinical trials uses histone deacetylase inhibitors (HDACi's as monotherapy or in combination with other agents. METHODOLOGY/PRINCIPAL FINDINGS: We have used a variety of cell-based and molecular/biochemical assays to show that two pan-HDAC inhibitors, trichostatin A and vorinostat, induce apoptosis in seven of eight human DLBCL cell lines. Consistent with previous reports implicating the BCL-2 family in regulating HDACi-induced apoptosis, ectopic over-expression of anti-apoptotic proteins BCL-2 and BCL-XL or pro-apoptotic protein BIM in these cell lines conferred further resistance or sensitivity, respectively, to HDACi treatment. Additionally, BCL-2 family antgonist ABT-737 increased the sensitivity of several DLBCL cell lines to vorinostat-induced apoptosis, including one cell line (SUDHL6 that is resistant to vorinostat alone. Moreover, two variants of the HDACi-sensitive SUDHL4 cell line that have decreased sensitivity to vorinostat showed up-regulation of BCL-2 family anti-apoptotic proteins such as BCL-XL and MCL-1, as well as decreased sensitivity to ABT-737. These results suggest that the regulation and overall balance of anti- to pro-apoptotic BCL-2 family protein expression is important in defining the sensitivity of DLBCL to HDACi-induced apoptosis. However, the sensitivity of DLBCL cell lines to HDACi treatment does not correlate with expression of any individual BCL-2 family member. CONCLUSIONS/SIGNIFICANCE: These studies indicate that the sensitivity of DLBCL to treatment with HDACi's is dependent on the complex regulation of BCL-2 family members and that BCL-2 antagonists may enhance the response of a subset of DLBCL patients to HDACi treatment.

Practical analysis of specificity-determining residues in protein families.

Science.gov (United States)

Chagoyen, Mónica; García-Martín, Juan A; Pazos, Florencio

2016-03-01

Determining the residues that are important for the molecular activity of a protein is a topic of broad interest in biomedicine and biotechnology. This knowledge can help understanding the protein's molecular mechanism as well as to fine-tune its natural function eventually with biotechnological or therapeutic implications. Some of the protein residues are essential for the function common to all members of a family of proteins, while others explain the particular specificities of certain subfamilies (like binding on different substrates or cofactors and distinct binding affinities). Owing to the difficulty in experimentally determining them, a number of computational methods were developed to detect these functional residues, generally known as 'specificity-determining positions' (or SDPs), from a collection of homologous protein sequences. These methods are mature enough for being routinely used by molecular biologists in directing experiments aimed at getting insight into the functional specificity of a family of proteins and eventually modifying it. In this review, we summarize some of the recent discoveries achieved through SDP computational identification in a number of relevant protein families, as well as the main approaches and software tools available to perform this type of analysis. © The Author 2015. Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

Scrapie susceptibility-linked polymorphisms modulate the in vitro conversion of sheep prion protein to protease-resistant forms

NARCIS (Netherlands)

Bossers, A.; Belt, P.B.G.M.; Raymond, G.J.; Caughey, B.; Vries, de R.; Smits, M.

1997-01-01

Prion diseases are natural transmissible neurodegenerative disorders in humans and animals. They are characterized by the accumulation of a protease-resistant scrapie-associated prion protein (PrPSc) of the host-encoded cellular prion protein (PrPC) mainly in the central nervous system.

The 1p-encoded protein stathmin and resistance of malignant gliomas to nitrosoureas.

Science.gov (United States)

Ngo, Teri-T B; Peng, Tien; Liang, Xing-Jie; Akeju, Oluwaseun; Pastorino, Sandra; Zhang, Wei; Kotliarov, Yuri; Zenklusen, Jean C; Fine, Howard A; Maric, Dragan; Wen, Patrick Y; De Girolami, Umberto; Black, Peter McL; Wu, Wells W; Shen, Rong-Fong; Jeffries, Neal O; Kang, Dong-Won; Park, John K

2007-04-18

Malignant gliomas are generally resistant to all conventional therapies. Notable exceptions are anaplastic oligodendrogliomas with loss of heterozygosity on chromosome 1p (1p+/-). Patients with 1p+/- anaplastic oligodendroglioma frequently respond to procarbazine, 1-(2-chloroethyl)-3-cyclohexyl-l-nitrosourea, and vincristine. Because the underlying biologic basis for this clinical finding is unclear, we evaluated differentially expressed 1p-encoded proteins in 1p+/- and 1p+/+ malignant glioma cell lines and then examined whether their expression was associated with outcome of patients with anaplastic oligodendroglioma. We used a comparative proteomic screen of A172 (1p+/-) and U251 (1p+/+) malignant glioma cell lines to identify differentially expressed 1p-encoded proteins, including stathmin, a microtubule-associated protein. 1p+/- and 1p+/+ anaplastic oligodendroglioma specimens from 24 patients were assessed for stathmin expression by immunohistochemistry. The relationship between stathmin expression and clinical outcome was assessed with Kaplan-Meier analyses. RNA inhibition and cDNA transfection experiments tested effects of stathmin under- and overexpression, respectively, on the in vitro and in vivo resistance of malignant glioma cells to treatment with nitrosourea. For in vivo resistance studies, 36 mice with intracranial and 16 mice with subcutaneous xenograft tumor implants were used (one tumor per mouse). Flow cytometry was used for cell cycle analysis. Immunoblotting was used to assess protein expression. All statistical tests were two-sided. Decreased stathmin expression in tumors was statistically significantly associated with loss of heterozygosity in 1p (Pnitrosourea-treated mice carrying xenograft tumors. Median survival of mice with stathmin+/- tumors was 95 days (95% CI = 68.7 to 121.3 days) and that of mice with stathmin+/+ tumors was 64 days (95% CI = 58.2 to 69.8 days) (difference = 31 days, 95% CI = 4.1 to 57.9 days; PNitrosoureas induced

No evidence for association of autism with rare heterozygous point mutations in Contactin-Associated Protein-Like 2 (CNTNAP2, or in Other Contactin-Associated Proteins or Contactins.

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John D Murdoch

2015-01-01

Full Text Available Contactins and Contactin-Associated Proteins, and Contactin-Associated Protein-Like 2 (CNTNAP2 in particular, have been widely cited as autism risk genes based on findings from homozygosity mapping, molecular cytogenetics, copy number variation analyses, and both common and rare single nucleotide association studies. However, data specifically with regard to the contribution of heterozygous single nucleotide variants (SNVs have been inconsistent. In an effort to clarify the role of rare point mutations in CNTNAP2 and related gene families, we have conducted targeted next-generation sequencing and evaluated existing sequence data in cohorts totaling 2704 cases and 2747 controls. We find no evidence for statistically significant association of rare heterozygous mutations in any of the CNTN or CNTNAP genes, including CNTNAP2, placing marked limits on the scale of their plausible contribution to risk.

Investigating the Role of the Host Multidrug Resistance Associated Protein Transporter Family in Burkholderia cepacia Complex Pathogenicity Using a Caenorhabditis elegans Infection Model.

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Tedesco, Pietro; Visone, Marco; Parrilli, Ermenegilda; Tutino, Maria Luisa; Perrin, Elena; Maida, Isabel; Fani, Renato; Ballestriero, Francesco; Santos, Radleigh; Pinilla, Clemencia; Di Schiavi, Elia; Tegos, George; de Pascale, Donatella

2015-01-01

This study investigated the relationship between host efflux system of the non-vertebrate nematode Caenorhabditis elegans and Burkholderia cepacia complex (Bcc) strain virulence. This is the first comprehensive effort to profile host-transporters within the context of Bcc infection. With this aim, two different toxicity tests were performed: a slow killing assay that monitors mortality of the host by intestinal colonization and a fast killing assay that assesses production of toxins. A Virulence Ranking scheme was defined, that expressed the toxicity of the Bcc panel members, based on the percentage of surviving worms. According to this ranking the 18 Bcc strains were divided in 4 distinct groups. Only the Cystic Fibrosis isolated strains possessed profound nematode killing ability to accumulate in worms' intestines. For the transporter analysis a complete set of isogenic nematode single Multidrug Resistance associated Protein (MRP) efflux mutants and a number of efflux inhibitors were interrogated in the host toxicity assays. The Bcc pathogenicity profile of the 7 isogenic C. elegans MRP knock-out strains functionality was classified in two distinct groups. Disabling host transporters enhanced nematode mortality more than 50% in 5 out of 7 mutants when compared to wild type. In particular mrp-2 was the most susceptible phenotype with increased mortality for 13 out 18 Bcc strains, whereas mrp-3 and mrp-4 knock-outs had lower mortality rates, suggesting a different role in toxin-substrate recognition. The use of MRP efflux inhibitors in the assays resulted in substantially increased (>40% on average) mortality of wild-type worms.

Supplementary Material for: Mycobacterium tuberculosis whole genome sequencing and protein structure modelling provides insights into anti-tuberculosis drug resistance

KAUST Repository

Phelan, Jody

2016-01-01

Abstract Background Combating the spread of drug resistant tuberculosis is a global health priority. Whole genome association studies are being applied to identify genetic determinants of resistance to anti-tuberculosis drugs. Protein structure and interaction modelling are used to understand the functional effects of putative mutations and provide insight into the molecular mechanisms leading to resistance. Methods To investigate the potential utility of these approaches, we analysed the genomes of 144 Mycobacterium tuberculosis clinical isolates from The Special Programme for Research and Training in Tropical Diseases (TDR) collection sourced from 20 countries in four continents. A genome-wide approach was applied to 127 isolates to identify polymorphisms associated with minimum inhibitory concentrations for first-line anti-tuberculosis drugs. In addition, the effect of identified candidate mutations on protein stability and interactions was assessed quantitatively with well-established computational methods. Results The analysis revealed that mutations in the genes rpoB (rifampicin), katG (isoniazid), inhA-promoter (isoniazid), rpsL (streptomycin) and embB (ethambutol) were responsible for the majority of resistance observed. A subset of the mutations identified in rpoB and katG were predicted to affect protein stability. Further, a strong direct correlation was observed between the minimum inhibitory concentration values and the distance of the mutated residues in the three-dimensional structures of rpoB and katG to their respective drugs binding sites. Conclusions Using the TDR resource, we demonstrate the usefulness of whole genome association and convergent evolution approaches to detect known and potentially novel mutations associated with drug resistance. Further, protein structural modelling could provide a means of predicting the impact of polymorphisms on drug efficacy in the absence of phenotypic data. These approaches could ultimately lead to novel

Impact of hormone-associated resistance to activated protein C on the thrombotic potential of oral contraceptives: a prospective observational study.

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Heiko Rühl

Full Text Available The increased thrombotic risk of oral contraceptives (OC has been attributed to various alterations of the hemostatic system, including acquired resistance to activated protein C (APC. To evaluate to what extent OC-associated APC resistance induces a prothrombotic state we monitored plasma levels of thrombin and molecular markers specific for thrombin formation in women starting OC use. Elevated plasma levels of thrombin have been reported to characterize situations of high thrombotic risk such as trauma-induced hypercoagulability, but have not yet been studied during OC use.Blood samples were collected prospectively from healthy women (n = 21 before and during three menstruation cycles after start of OC. APC resistance was evaluated using a thrombin generation-based assay. Plasma levels of thrombin and APC were directly measured using highly sensitive oligonucleotide-based enzyme capture assay (OECA technology. Thrombin generation markers and other hemostasis parameters were measured additionally.All women developed APC resistance as indicated by an increased APC sensitivity ratio compared with baseline after start of OC (p = 0.0003. Simultaneously, plasma levels of thrombin, prothrombin fragment 1+2, and of thrombin-antithrombin complexes did not change, ruling out increased thrombin formation. APC plasma levels were also not influenced by OC use, giving further evidence that increased thrombin formation did not occur.In the majority of OC users no enhanced thrombin formation occurs despite the development of APC resistance. It cannot be ruled out, however, that thrombin formation might occur to a greater extent in the presence of additional risk factors. If this were the case, endogenous thrombin levels might be a potential biomarker candidate to identify women at high thrombotic risk during OC treatment. Large-scale studies are required to assess the value of plasma levels of thrombin as predictors of OC-associated thrombotic risk.

Identification of cytosolic peroxisome proliferator binding protein as a member of the heat shock protein HSP70 family.

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Alvares, K; Carrillo, A; Yuan, P M; Kawano, H; Morimoto, R I; Reddy, J K

1990-01-01

Clofibrate and many of its structural analogues induce proliferation of peroxisomes in the hepatic parenchymal cells of rodents and certain nonrodent species including primates. This induction is tissue specific, occurring mainly in the liver parenchymal cells and to a lesser extent in the kidney cortical epithelium. The induction of peroxisomes is associated with a predictable pleiotropic response, characterized by hepatomegaly, and increased activities and mRNA levels of certain peroxisomal enzymes. Using affinity chromatography, we had previously isolated a protein that binds to clofibric acid. We now show that this protein is homologous with the heat shock protein HSP70 family by analysis of amino acid sequences of isolated peptides from trypsin-treated clofibric acid binding protein and by cross-reactivity with a monoclonal antibody raised against the conserved region of the 70-kDa heat shock proteins. The clofibric acid-Sepharose column could bind HSP70 proteins isolated from various species, which could then be eluted with either clofibric acid or ATP. Conversely, when a rat liver cytosol containing multiple members of the HSP70 family was passed through an ATP-agarose column, and eluted with clofibric acid, only P72 (HSC70) was eluted. These results suggest that clofibric acid, a peroxisome proliferator, preferentially interacts with P72 at or near the ATP binding site. Images PMID:2371272

Techniques for overcoming community resistance to family planning programs.

Science.gov (United States)

Palley, H A

1968-01-01

Methods of overcoming resistance to publicly subsidized family planning programs are discussed. The main sources of opposition include groups that oppose family planning for moral reasons, and those who object to the spending of government funds to provide services and information. Such opposition can be weakened by indicating that family planning clinics fulf: 11 important medical needs. Presenting social justification for family planning can help to lower oppostion. In order to secure participation in the programs by low income groups it is essential to have community leaders involved in policy decisions and to use indigenous community paraprofessionals in the clinics. A coalition of representatives of the poor community and the health and welfare system, aided by the community organization, can lead to an effective family planning program.

Whey protein consumption after resistance exercise reduces energy intake at a post-exercise meal.

Science.gov (United States)

Monteyne, Alistair; Martin, Alex; Jackson, Liam; Corrigan, Nick; Stringer, Ellen; Newey, Jack; Rumbold, Penny L S; Stevenson, Emma J; James, Lewis J

2018-03-01

Protein consumption after resistance exercise potentiates muscle protein synthesis, but its effects on subsequent appetite in this context are unknown. This study examined appetite and energy intake following consumption of protein- and carbohydrate-containing drinks after resistance exercise. After familiarisation, 15 resistance training males (age 21 ± 1 years, body mass 78.0 ± 11.9 kg, stature 1.78 ± 0.07 m) completed two randomised, double-blind trials, consisting of lower-body resistance exercise, followed by consumption of a whey protein (PRO 23.9 ± 3.6 g protein) or dextrose (CHO 26.5 ± 3.8 g carbohydrate) drink in the 5 min post-exercise. An ad libitum meal was served 60 min later, with subjective appetite measured throughout. Drinks were flavoured and matched for energy content and volume. The PRO drink provided 0.3 g/kg body mass protein. Ad libitum energy intake (PRO 3742 ± 994 kJ; CHO 4172 ± 1132 kJ; P = 0.007) and mean eating rate (PRO 339 ± 102 kJ/min; CHO 405 ± 154 kJ/min; P = 0.009) were lower during PRO. The change in eating rate was associated with the change in energy intake (R = 0.661, P = 0.007). No interaction effects were observed for subjective measures of appetite. The PRO drink was perceived as creamier and thicker, and less pleasant, sweet and refreshing (P consumption after resistance exercise reduces subsequent energy intake, and this might be partially mediated by a reduced eating rate. Whilst this reduced energy intake is unlikely to impair hypertrophy, it may be of value in supporting an energy deficit for weight loss.

Receptor-interacting protein (RIP) kinase family

OpenAIRE

Zhang, Duanwu; Lin, Juan; Han, Jiahuai

2010-01-01

Receptor-interacting protein (RIP) kinases are a group of threonine/serine protein kinases with a relatively conserved kinase domain but distinct non-kinase regions. A number of different domain structures, such as death and caspase activation and recruitment domain (CARD) domains, were found in different RIP family members, and these domains should be keys in determining the specific function of each RIP kinase. It is known that RIP kinases participate in different biological processes, incl...

Diversifying Selection in the Wheat Stem Rust Fungus Acts Predominantly on Pathogen-Associated Gene Families and Reveals Candidate Effectors

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Jana eSperschneider

2014-09-01

Full Text Available Plant pathogens cause severe losses to crop plants and threaten global food production. One striking example is the wheat stem rust fungus, Puccinia graminis f. sp. tritici, which can rapidly evolve new virulent pathotypes in response to resistant host lines. Like several other filamentous fungal and oomycete plant pathogens, its genome features expanded gene families that have been implicated in host-pathogen interactions, possibly encoding effector proteins that interact directly with target host defence proteins. Previous efforts to understand virulence largely relied on the prediction of secreted, small and cysteine-rich proteins as candidate effectors and thus delivered an overwhelming number of candidates. Here, we implement an alternative analysis strategy that uses the signal of adaptive evolution as a line of evidence for effector function, combined with comparative information and expression data. We demonstrate that in planta up-regulated genes that are rapidly evolving are found almost exclusively in pathogen-associated gene families, affirming the impact of host-pathogen co-evolution on genome structure and the adaptive diversification of specialised gene families. In particular, we predict 42 effector candidates that are conserved only across pathogens, induced during infection and rapidly evolving. One of our top candidates has recently been shown to induce genotype-specific hypersensitive cell death in wheat. This shows that comparative genomics incorporating the evolutionary signal of adaptation is powerful for predicting effector candidates for laboratory verification. Our system can be applied to a wide range of pathogens and will give insight into host-pathogen dynamics, ultimately leading to progress in strategies for disease control.

Microarray-based analysis of IncA/C plasmid-associated genes from multidrug-resistant Salmonella enterica.

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Lindsey, Rebecca L; Frye, Jonathan G; Fedorka-Cray, Paula J; Meinersmann, Richard J

2011-10-01

In the family Enterobacteriaceae, plasmids have been classified according to 27 incompatibility (Inc) or replicon types that are based on the inability of different plasmids with the same replication mechanism to coexist in the same cell. Certain replicon types such as IncA/C are associated with multidrug resistance (MDR). We developed a microarray that contains 286 unique 70-mer oligonucleotide probes based on sequences from five IncA/C plasmids: pYR1 (Yersinia ruckeri), pPIP1202 (Yersinia pestis), pP99-018 (Photobacterium damselae), pSN254 (Salmonella enterica serovar Newport), and pP91278 (Photobacterium damselae). DNA from 59 Salmonella enterica isolates was hybridized to the microarray and analyzed for the presence or absence of genes. These isolates represented 17 serovars from 14 different animal hosts and from different geographical regions in the United States. Qualitative cluster analysis was performed using CLUSTER 3.0 to group microarray hybridization results. We found that IncA/C plasmids occurred in two lineages distinguished by a major insertion-deletion (indel) region that contains genes encoding mostly hypothetical proteins. The most variable genes were represented by transposon-associated genes as well as four antimicrobial resistance genes (aphA, merP, merA, and aadA). Sixteen mercury resistance genes were identified and highly conserved, suggesting that mercury ion-related exposure is a stronger pressure than anticipated. We used these data to construct a core IncA/C genome and an accessory genome. The results of our studies suggest that the transfer of antimicrobial resistance determinants by transfer of IncA/C plasmids is somewhat less common than exchange within the plasmids orchestrated by transposable elements, such as transposons, integrating and conjugative elements (ICEs), and insertion sequence common regions (ISCRs), and thus pose less opportunity for exchange of antimicrobial resistance.

Marked variability in the extent of protein disorder within and between viral families.

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Ravindra Pushker

Full Text Available Intrinsically disordered regions in eukaryotic proteomes contain key signaling and regulatory modules and mediate interactions with many proteins. Many viral proteomes encode disordered proteins and modulate host factors through the use of short linear motifs (SLiMs embedded within disordered regions. However, the degree of viral protein disorder across different viruses is not well understood, so we set out to establish the constraints acting on viruses, in terms of their use of disordered protein regions. We surveyed predicted disorder across 2,278 available viral genomes in 41 families, and correlated the extent of disorder with genome size and other factors. Protein disorder varies strikingly between viral families (from 2.9% to 23.1% of residues, and also within families. However, this substantial variation did not follow the established trend among their hosts, with increasing disorder seen across eubacterial, archaebacterial, protists, and multicellular eukaryotes. For example, among large mammalian viruses, poxviruses and herpesviruses showed markedly differing disorder (5.6% and 17.9%, respectively. Viral families with smaller genome sizes have more disorder within each of five main viral types (ssDNA, dsDNA, ssRNA+, dsRNA, retroviruses, except for negative single-stranded RNA viruses, where disorder increased with genome size. However, surveying over all viruses, which compares tiny and enormous viruses over a much bigger range of genome sizes, there is no strong association of genome size with protein disorder. We conclude that there is extensive variation in the disorder content of viral proteomes. While a proportion of this may relate to base composition, to extent of gene overlap, and to genome size within viral types, there remain important additional family and virus-specific effects. Differing disorder strategies are likely to impact on how different viruses modulate host factors, and on how rapidly viruses can evolve novel

Expression of P-glycoprotein and multidrug resistance associated protein in Ehrlich ascites tumor cells after fractionated irradiation

International Nuclear Information System (INIS)

Nielsen, Dorte; Maare, Christian; Eriksen, Jens; Litman, Thomas; Skovsgaard, Torben

2001-01-01

Purpose: To characterize irradiated murine tumor cells with respect to drug resistance, drug kinetics, and ATPase activity, and to evaluate the possible role of P-glycoprotein (PGP) and murine multidrug resistance associated protein (Mrp1) in the drug-resistant phenotype of these cells. Methods and Materials: Sensitive Ehrlich ascites tumor cells (EHR2) were in vitro exposed to fractionated irradiation (60 Gy). Western blot analysis was performed for determination of PGP and Mrp1, reverse transcriptase-polymerase chain reaction (RT-PCR) for determination of mdr1a + b mRNA, and semiquantitative RT-PCR for Mrp1 mRNA. The clonogenic assay was applied to investigate sensitivity, whereas the steady-state drug accumulation of daunorubicin (DNR), 3 H-vincristine (VCR), and 3 H-etoposide (VP16) was measured by spectrofluorometry and scintillation counting, respectively. For determining of ATPase activity, the release of inorganic phosphate from ATP was quantified using a colorimetric method. Results: Compared with EHR2, the irradiated cell line EHR2/irr showed increased expression of PGP (threefold), Mrp1 (eightfold), and Mrp1 mRNA (sixfold), and a slight reduction of mdr1b mRNA, whereas mdr1a was present in EHR2 but could not be detected in EHR2/irr. EHR2/irr developed sixfold resistance to VP16, twofold resistance to vincristine, but remained sensitive to DNR. Addition of the PGP inhibitor, verapamil (VER) or depletion of glutathione by buthionine sulfoximine (BSO) partly reversed the resistance in EHR2/irr. In EHR2/irr, the steady-state accumulation of 3 H-VCR and 3 H-VP16 was significantly decreased as compared with EHR2, whereas the accumulation of DNR was unchanged. The ATPase activity of plasma membrane vesicles prepared from EHR2/irr cells was similar to that of wild-type EHR2 cells. The ATPase activity was neither stimulated by vinblastine nor VER. Conclusion: Irradiation induced a multidrug-resistant phenotype in sensitive tumor cells. This phenotype was

Preliminary evidence for obesity-associated insulin resistance in adolescents without elevations of inflammatory cytokines

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Cohen Jessica I

2012-06-01

Full Text Available Abstract Background To ascertain whether the associations between obesity, inflammation, and insulin resistance established in human adult studies are found among adolescents. Methods We contrasted 36 obese and 24 lean youth on fasting glucose, insulin levels, lipid profile, hemoglobin A1C, markers of hepatic function, white blood cell count, C-reactive protein (CRP and fibrinogen levels. The cytokines IL-6, TNF-α, IFN-γ, IL-10 and IL-4 and the adipokines leptin, resistin, and adiponectin were also compared between the two groups. The fasting glucose and insulin values were used to estimate the degree of insulin resistance with the homeostatic model assessment of insulin resistance (HOMA-IR. T-tests and correlations were run to examine group differences and associations between groups. In addition, regression analyses were used to ascertain whether the markers of inflammation were predictive of the degree of insulin resistance. Results Although obese adolescents had clear evidence of insulin resistance, only CRP, fibrinogen and leptin were elevated; there were no group differences in pro- or anti-inflammatory cytokines nor adiponectin and resistin. Anthropometric measures of obesity and level of insulin resistance were highly correlated to the acute phase reactants CRP and fibrinogen; however, the degree of insulin resistance was not predicted by the pro- or anti-inflammatory cytokine markers. Obese adolescents had higher white blood cell counts. In addition they had higher circulating alanine aminotransferase concentrations and lower circulating albumin and total protein than lean adolescents, possibly as a result of hepatocyte damage from fatty liver. Conclusion Unlike rodent or adult studies, we found that wide-spread systemic inflammation is not necessarily associated with insulin resistance among adolescents. This finding does not support the current paradigm that the associations between obesity and insulin resistance are, to a

Navigating into the binding pockets of the HER family protein kinases: discovery of novel EGFR inhibitor as antitumor agent.

Science.gov (United States)

Liu, Wei; Ning, Jin-Feng; Meng, Qing-Wei; Hu, Jing; Zhao, Yan-Bin; Liu, Chao; Cai, Li

2015-01-01

The epidermal growth factor receptor (EGFR) family has been validated as a successful antitumor drug target for decades. Known EGFR inhibitors were exposed to distinct drug resistance against the various EGFR mutants within non-small-cell lung cancer (NSCLC), particularly the T790M mutation. Although so far a number of studies have been reported on the development of third-generation EGFR inhibitors for overcoming the resistance issue, the design procedure largely depends on the intuition of medicinal chemists. Here we retrospectively make a detailed analysis of the 42 EGFR family protein crystal complexes deposited in the Protein Data Bank (PDB). Based on the analysis of inhibitor binding modes in the kinase catalytic cleft, we identified a potent EGFR inhibitor (compound A-10) against drug-resistant EGFR through fragment-based drug design. This compound showed at least 30-fold more potency against EGFR T790M than the two control molecules erlotinib and gefitinib in vitro. Moreover, it could exhibit potent HER2 inhibitory activities as well as tumor growth inhibitory activity. Molecular docking studies revealed a structural basis for the increased potency and mutant selectivity of this compound. Compound A-10 may be selected as a promising candidate in further preclinical studies. In addition, our findings could provide a powerful strategy to identify novel selective kinase inhibitors on the basis of detailed kinase-ligand interaction space in the PDB.

Slipins: ancient origin, duplication and diversification of the stomatin protein family

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Young J Peter W

2008-02-01

Full Text Available Abstract Background Stomatin is a membrane protein that was first isolated from human red blood cells. Since then, a number of stomatin-like proteins have been identified in all three domains of life. The conservation among these proteins is remarkable, with bacterial and human homologs sharing 50 % identity. Despite being associated with a variety of diseases such as cancer, kidney failure and anaemia, precise functions of these proteins remain unclear. Results We have constructed a comprehensive phylogeny of all 'stomatin-like' sequences that share a 150 amino acid domain. We show these proteins comprise an ancient family that arose early in prokaryotic evolution, and we propose a new nomenclature that reflects their phylogeny, based on the name "slipin" (stomatin-like protein. Within prokaryotes there are two distinct subfamilies that account for the two different origins of the eight eukaryotic stomatin subfamilies, one of which gave rise to eukaryotic SLP-2, renamed here "paraslipin". This was apparently acquired through the mitochondrial endosymbiosis and is widely distributed amongst the major kingdoms. The other prokaryotic subfamily gave rise to the ancestor of the remaining seven eukaryotic subfamilies. The highly diverged "alloslipin" subfamily is represented only by fungal, viral and ciliate sequences. The remaining six subfamilies, collectively termed "slipins", are confined to metazoa. Protostome stomatin, as well as a newly reported arthropod subfamily slipin-4, are restricted to invertebrate groups, whilst slipin-1 (previously SLP-1 is present in nematodes and higher metazoa. In vertebrates, the stomatin family expanded considerably, with at least two duplication events giving rise to podocin and slipin-3 subfamilies (previously SLP-3, with the retained ancestral sequence giving rise to vertebrate stomatin. Conclusion Stomatin-like proteins have their origin in an ancient duplication event that occurred early on in the evolution

Positive muscle protein net balance and differential regulation of atrogene expression after resistance exercise and milk protein supplementation

DEFF Research Database (Denmark)

Reitelseder, Søren; Agergaard, Jakob; Doessing, Simon

2014-01-01

Purpose Resistance exercise and amino acid availability are positive regulators of muscle protein net balance (NB). However, anabolic responses to resistance exercise and protein supplementation deserve further elucidation. The purpose was to compare intakes of whey, caseinate (both: 0.30 g/kg lean...... body mass), or a non-caloric control after heavy resistance exercise on protein turnover and mRNA expressions of forkhead homeobox type O (FOXO) isoforms, muscle RING finger 1 (MuRF1), and Atrogin1 in young healthy males. Methods Protein turnover was determined by stable isotope-labeled leucine...

Two novel heat-soluble protein families abundantly expressed in an anhydrobiotic tardigrade.

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Ayami Yamaguchi

Full Text Available Tardigrades are able to tolerate almost complete dehydration by reversibly switching to an ametabolic state. This ability is called anhydrobiosis. In the anhydrobiotic state, tardigrades can withstand various extreme environments including space, but their molecular basis remains largely unknown. Late embryogenesis abundant (LEA proteins are heat-soluble proteins and can prevent protein-aggregation in dehydrated conditions in other anhydrobiotic organisms, but their relevance to tardigrade anhydrobiosis is not clarified. In this study, we focused on the heat-soluble property characteristic of LEA proteins and conducted heat-soluble proteomics using an anhydrobiotic tardigrade. Our heat-soluble proteomics identified five abundant heat-soluble proteins. All of them showed no sequence similarity with LEA proteins and formed two novel protein families with distinct subcellular localizations. We named them Cytoplasmic Abundant Heat Soluble (CAHS and Secretory Abundant Heat Soluble (SAHS protein families, according to their localization. Both protein families were conserved among tardigrades, but not found in other phyla. Although CAHS protein was intrinsically unstructured and SAHS protein was rich in β-structure in the hydrated condition, proteins in both families changed their conformation to an α-helical structure in water-deficient conditions as LEA proteins do. Two conserved repeats of 19-mer motifs in CAHS proteins were capable to form amphiphilic stripes in α-helices, suggesting their roles as molecular shield in water-deficient condition, though charge distribution pattern in α-helices were different between CAHS and LEA proteins. Tardigrades might have evolved novel protein families with a heat-soluble property and this study revealed a novel repertoire of major heat-soluble proteins in these anhydrobiotic animals.

Enhancing the prediction of protein pairings between interacting families using orthology information

Directory of Open Access Journals (Sweden)

Pazos Florencio

2008-01-01

Full Text Available Abstract Background It has repeatedly been shown that interacting protein families tend to have similar phylogenetic trees. These similarities can be used to predicting the mapping between two families of interacting proteins (i.e. which proteins from one family interact with which members of the other. The correct mapping will be that which maximizes the similarity between the trees. The two families may eventually comprise orthologs and paralogs, if members of the two families are present in more than one organism. This fact can be exploited to restrict the possible mappings, simply by impeding links between proteins of different organisms. We present here an algorithm to predict the mapping between families of interacting proteins which is able to incorporate information regarding orthologues, or any other assignment of proteins to "classes" that may restrict possible mappings. Results For the first time in methods for predicting mappings, we have tested this new approach on a large number of interacting protein domains in order to statistically assess its performance. The method accurately predicts around 80% in the most favourable cases. We also analysed in detail the results of the method for a well defined case of interacting families, the sensor and kinase components of the Ntr-type two-component system, for which up to 98% of the pairings predicted by the method were correct. Conclusion Based on the well established relationship between tree similarity and interactions we developed a method for predicting the mapping between two interacting families using genomic information alone. The program is available through a web interface.

National Military Family Association

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Insulin-resistance and metabolic syndrome are related to executive function in women in a large family-based study

NARCIS (Netherlands)

M. Schuur (Maaike); P. Henneman (Peter); J.C. van Swieten (John); M.C. Zillikens (Carola); I. de Koning (Inge); A.C.J.W. Janssens (Cécile); J.C.M. Witteman (Jacqueline); Y.S. Aulchenko (Yurii); R.R. Frants (Rune); B.A. Oostra (Ben); J.A.P. Willems van Dijk (Ko); C.M. van Duijn (Cornelia)

2010-01-01

textabstractWhile type 2 diabetes is well-known to be associated with poorer cognitive performance, few studies have reported on the association of metabolic syndrome (MetS) and contributing factors, such as insulin-resistance (HOMA-IR), low adiponectin-, and high C-reactive protein (CRP)- levels.

[Factors associated with insulin resistence in rural populations].

Science.gov (United States)

Mendes, Larissa Loures; Gazzinelli, Andréa; Velásquez-Meléndez, Gustavo

2009-04-01

This study explores the relations of anthropometric, body composition assessments, biochemical and hemodynamic parameters with insulin resistance in two rural communities. Sample was composed by adults aged 18 or older, both sexes. Participants were excluded if pregnant and diabetic. Data collection included demographic lifestyle, hemodynamic, anthropometric and biochemical variables. From the 567 subjects, 50.4% were men and 49.6%, women. Most of the sample was non-white (75.7%), lived with partner (69.3%) and had low educational level. Overweight and obesity prevalences were 17.4% and 5.5%, respectively. Multivariate analysis found risk factors associated to insulin resistance for non-diabetic adults with low income and educational level: overweight, obesity, elevated waist-to-hip ratio, C-reactive protein and skin color.

Resveratrol Inhibits Porcine Intestinal Glucose and Alanine Transport: Potential Roles of Na+/K+-ATPase Activity, Protein Kinase A, AMP-Activated Protein Kinase and the Association of Selected Nutrient Transport Proteins with Detergent Resistant Membranes

Directory of Open Access Journals (Sweden)

Stefanie Klinger

2018-03-01

Full Text Available Background: Beneficial effects of Resveratrol (RSV have been demonstrated, including effects on transporters and channels. However, little is known about how RSV influences intestinal transport. The aim of this study was to further characterize the effects of RSV on intestinal transport and the respective mechanisms. Methods: Porcine jejunum and ileum were incubated with RSV (300 µM, 30 min in Ussing chambers (functional studies and tissue bathes (detection of protein expression, phosphorylation, association with detergent resistant membranes (DRMs. Results: RSV reduced alanine and glucose-induced short circuit currents (ΔIsc and influenced forskolin-induced ΔIsc. The phosphorylation of sodium–glucose-linked transporter 1 (SGLT1, AMP-activated protein kinase (AMPK, protein kinase A substrates (PKA-S and liver kinase B1 (LKB1 increased but a causative relation to the inhibitory effects could not directly be established. The DRM association of SGLT1, peptide transporter 1 (PEPT1 and (phosphorylated Na+/H+-exchanger 3 (NHE3 did not change. Conclusion: RSV influences the intestinal transport of glucose, alanine and chloride and is likely to affect other transport processes. As the effects of protein kinase activation vary between the intestinal localizations, it would appear that increasing cyclic adenosine monophosphate (cAMP levels are part of the mechanism. Nonetheless, the physiological responses depend on cell type-specific structures.

Diastolic dysfunction is associated with insulin resistance, but not with aldosterone level in normotensive offspring of hypertensive families.

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Zizek, Bogomir; Poredos, Pavel; Trojar, Andrej; Zeljko, Tadej

2008-01-01

We investigated left ventricular (LV) morphology and function in association with insulin level/insulin resistance (IR) and aldosterone level in normotensive offspring of subjects with essential hypertension (familial trait, FT). The study encompassed 76 volunteers of whom 44 were normotensive with FT (aged 28-39 years) and 32 age-matched controls without FT. LV mass and function were measured using conventional echocardiography and tissue Doppler imaging. LV diastolic function was reported as peak septal annular velocities (E(m) and E(m)/A(m) ratio) in tissue Doppler imaging. Fasting insulin and aldosterone were determined. In subjects with FT, the LV mass was higher than in controls (92.14 +/- 24.02 vs. 70.08 +/- 20.58 g; p < 0.001). The study group had a worse LV diastolic function than control subjects (lower E(m) and E(m)/A(m) ratio; p < 0.001). In subjects with FT, the E(m)/A(m) ratio was independently associated with IR (partial p = 0.029 in multivariate model, R(2) = 0.51), but not with LV mass. The aldosterone level was comparable in both groups. In normotensive individuals with FT, LV morphological and functional abnormalities were found. LV dysfunction but not an increase in LV mass is associated with IR. The aldosterone level is probably not responsible for the development of early hypertensive heart disease. (c) 2008 S. Karger AG, Basel.

Palmitoylation of POTE family proteins for plasma membrane targeting

International Nuclear Information System (INIS)

Das, Sudipto; Ise, Tomoko; Nagata, Satoshi; Maeda, Hiroshi; Bera, Tapan K.; Pastan, Ira

2007-01-01

The POTE gene family is composed of 13 paralogs and likely evolved by duplications and remodeling of the human genome. One common property of POTE proteins is their localization on the inner aspect of the plasma membrane. To determine the structural elements required for membrane localization, we expressed mutants of different POTEs in 293T cells as EGFP fusion proteins. We also tested their palmitoylation by a biotin-switch assay. Our data indicate that the membrane localizations of different POTEs are mediated by similar 3-4 short cysteine rich repeats (CRRs) near the amino-terminuses and that palmitoylation on paired cysteine residues in each CRR motif is responsible for the localization. Multiple palmitoylation in the small CRRs can result in the strong association of whole POTEs with plasma membrane

Redundancy and divergence in the amyloid precursor protein family.

Science.gov (United States)

Shariati, S Ali M; De Strooper, Bart

2013-06-27

Gene duplication provides genetic material required for functional diversification. An interesting example is the amyloid precursor protein (APP) protein family. The APP gene family has experienced both expansion and contraction during evolution. The three mammalian members have been studied quite extensively in combined knock out models. The underlying assumption is that APP, amyloid precursor like protein 1 and 2 (APLP1, APLP2) are functionally redundant. This assumption is primarily supported by the similarities in biochemical processing of APP and APLPs and on the fact that the different APP genes appear to genetically interact at the level of the phenotype in combined knockout mice. However, unique features in each member of the APP family possibly contribute to specification of their function. In the current review, we discuss the evolution and the biology of the APP protein family with special attention to the distinct properties of each homologue. We propose that the functions of APP, APLP1 and APLP2 have diverged after duplication to contribute distinctly to different neuronal events. Our analysis reveals that APLP2 is significantly diverged from APP and APLP1. Copyright © 2013 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

Irisin is Associated with Urotensin II and Protein Energy Wasting in Hemodialysis Patients

Directory of Open Access Journals (Sweden)

Wan-Yu He

2016-02-01

Full Text Available Aims/Introduction: Irisin is a newly identified myokine which can promote energy expenditure. Urotensin II (UII is identified as the most potent mammalian vasoconstrictor to date. Previous studies showed that UII can aggravate insulin resistance while irisin alleviate insulin resistance. Through this study, it is our aim to elucidate if UII can induce insulin resistance and also have an association with the irisin level in hemodialysis (HD patients. Materials and Methods: One hundred and twenty-eight patients on maintenance hemodialysis treatment and forty healthy subjects were enrolled in this study. Blood irisin concentrations and UII concentrations were measured by ELISA and RIA respectively. The body composition was analyzed by bioelectrical impedance. Results: The serum irisin levels and UII levels were both significantly lower in HD patients in comparison to that of the healthy subjects. The serum irisin levels were lower in HD patients with protein energy wasting than those of the patients without protein energy wasting. The independent determinants of circulating Ln (irisin (the natural logarithm of irisin were UII lean body mass and patients with protein energy wasting. Conclusions: Our results are the first to provide the clinical evidence of the association among irisin, UII, and protein energy wasting. Our results hint that UII and protein energy wasting might inhibit the release or synthesis of irisin from skeletal muscles in HD patients.

Evolutionary gradient of predicted nuclear localization signals (NLS)-bearing proteins in genomes of family Planctomycetaceae.

Science.gov (United States)

Guo, Min; Yang, Ruifu; Huang, Chen; Liao, Qiwen; Fan, Guangyi; Sun, Chenghang; Lee, Simon Ming-Yuen

2017-04-04

The nuclear envelope is considered a key classification marker that distinguishes prokaryotes from eukaryotes. However, this marker does not apply to the family Planctomycetaceae, which has intracellular spaces divided by lipidic intracytoplasmic membranes (ICMs). Nuclear localization signal (NLS), a short stretch of amino acid sequence, destines to transport proteins from cytoplasm into nucleus, and is also associated with the development of nuclear envelope. We attempted to investigate the NLS motifs in Planctomycetaceae genomes to demonstrate the potential molecular transition in the development of intracellular membrane system. In this study, we identified NLS-like motifs that have the same amino acid compositions as experimentally identified NLSs in genomes of 11 representative species of family Planctomycetaceae. A total of 15 NLS types and 170 NLS-bearing proteins were detected in the 11 strains. To determine the molecular transformation, we compared NLS-bearing protein abundances in the 11 representative Planctomycetaceae genomes with them in genomes of 16 taxonomically varied microorganisms: nine bacteria, two archaea and five fungi. In the 27 strains, 29 NLS types and 1101 NLS-bearing proteins were identified, principal component analysis showed a significant transitional gradient from bacteria to Planctomycetaceae to fungi on their NLS-bearing protein abundance profiles. Then, we clustered the 993 non-redundant NLS-bearing proteins into 181 families and annotated their involved metabolic pathways. Afterwards, we aligned the ten types of NLS motifs from the 13 families containing NLS-bearing proteins among bacteria, Planctomycetaceae or fungi, considering their diversity, length and origin. A transition towards increased complexity from non-planctomycete bacteria to Planctomycetaceae to archaea and fungi was detected based on the complexity of the 10 types of NLS-like motifs in the 13 NLS-bearing proteins families. The results of this study reveal that

Oncogenic Signaling by Leukemia-Associated Mutant Cbl Proteins

Science.gov (United States)

Nadeau, Scott; An, Wei; Palermo, Nick; Feng, Dan; Ahmad, Gulzar; Dong, Lin; Borgstahl, Gloria E. O.; Natarajan, Amarnath; Naramura, Mayumi; Band, Vimla; Band, Hamid

2013-01-01

Members of the Cbl protein family (Cbl, Cbl-b, and Cbl-c) are E3 ubiquitin ligases that have emerged as critical negative regulators of protein tyrosine kinase (PTK) signaling. This function reflects their ability to directly interact with activated PTKs and to target them as well as their associated signaling components for ubiquitination. Given the critical roles of PTK signaling in driving oncogenesis, recent studies in animal models and genetic analyses in human cancer have firmly established that Cbl proteins function as tumor suppressors. Missense mutations or small in-frame deletions within the regions of Cbl protein that are essential for its E3 activity have been identified in nearly 5% of leukemia patients with myelodysplastic/myeloproliferative disorders. Based on evidence from cell culture studies, in vivo models and clinical data, we discuss the potential signaling mechanisms of mutant Cbl-driven oncogenesis. Mechanistic insights into oncogenic Cbl mutants and associated animal models are likely to enhance our understanding of normal hematopoietic stem cell homeostasis and provide avenues for targeted therapy of mutant Cbl-driven cancers. PMID:23997989

Antifolate resistance mediated by the multidrug resistance proteins MRP1 and MRP2

NARCIS (Netherlands)

Hooijberg, J. H.; Broxterman, H. J.; Kool, M.; Assaraf, Y. G.; Peters, G. J.; Noordhuis, P.; Scheper, R. J.; Borst, P.; Pinedo, H. M.; Jansen, G.

1999-01-01

Transfection of multidrug resistance proteins (MRPs) MRP1 and MRP2 in human ovarian carcinoma 2008 cells conferred a marked level of resistance to short-term (1-4 h) exposure to the polyglutamatable antifolates methotrexate (MTX; 21-74-fold), ZD1694 (4-138-fold), and GW1843 (101-156-fold). Evidence

Comparative genomics of the IncA/C multidrug resistance plasmid family.

Science.gov (United States)

Fricke, W Florian; Welch, Timothy J; McDermott, Patrick F; Mammel, Mark K; LeClerc, J Eugene; White, David G; Cebula, Thomas A; Ravel, Jacques

2009-08-01

Multidrug resistance (MDR) plasmids belonging to the IncA/C plasmid family are widely distributed among Salmonella and other enterobacterial isolates from agricultural sources and have, at least once, also been identified in a drug-resistant Yersinia pestis isolate (IP275) from Madagascar. Here, we present the complete plasmid sequences of the IncA/C reference plasmid pRA1 (143,963 bp), isolated in 1971 from the fish pathogen Aeromonas hydrophila, and of the cryptic IncA/C plasmid pRAx (49,763 bp), isolated from Escherichia coli transconjugant D7-3, which was obtained through pRA1 transfer in 1980. Using comparative sequence analysis of pRA1 and pRAx with recent members of the IncA/C plasmid family, we show that both plasmids provide novel insights into the evolution of the IncA/C MDR plasmid family and the minimal machinery necessary for stable IncA/C plasmid maintenance. Our results indicate that recent members of the IncA/C plasmid family evolved from a common ancestor, similar in composition to pRA1, through stepwise integration of horizontally acquired resistance gene arrays into a conserved plasmid backbone. Phylogenetic comparisons predict type IV secretion-like conjugative transfer operons encoded on the shared plasmid backbones to be closely related to a group of integrating conjugative elements, which use conjugative transfer for horizontal propagation but stably integrate into the host chromosome during vegetative growth. A hipAB toxin-antitoxin gene cluster found on pRA1, which in Escherichia coli is involved in the formation of persister cell subpopulations, suggests persistence as an early broad-spectrum antimicrobial resistance mechanism in the evolution of IncA/C resistance plasmids.

The SNARE protein SNAP23 and the SNARE-interacting protein Munc18c in human skeletal muscle are implicated in insulin resistance/type 2 diabetes

DEFF Research Database (Denmark)

Boström, Pontus; Andersson, Linda; Vind, Birgitte

2010-01-01

/cytosolic compartment in the patients with the type 2 diabetes. Expression of the SNARE-interacting protein Munc18c was higher in skeletal muscle from patients with type 2 diabetes. Studies in L6 cells showed that Munc18c promoted the expression of SNAP23. CONCLUSIONS: We have translated our previous in vitro results......OBJECTIVE: Our previous studies suggest that the SNARE protein synaptosomal-associated protein of 23 kDa (SNAP23) is involved in the link between increased lipid levels and insulin resistance in cardiomyocytes. The objective was to determine whether SNAP23 may also be involved in the known...... association between lipid accumulation in skeletal muscle and insulin resistance/type 2 diabetes in humans, as well as to identify a potential regulator of SNAP23. RESEARCH DESIGN AND METHODS: We analyzed skeletal muscle biopsies from patients with type 2 diabetes and healthy, insulin-sensitive control...

Characterisation of the nascent polypeptide-associated complex in fission yeast

DEFF Research Database (Denmark)

Andersen, Katrine M; Semple, Colin A; Hartmann-Petersen, Rasmus

2007-01-01

with other cell proteins, but has also been found to associate with DNA junctions, and to be involved in other processes including transcription regulation and mitochondrial protein import.Here, we characterize NAC in fission yeast. We find that NAC is associated with ribosomes, while a significant fraction...... defects in protein degradation. Accordingly, we find that the NAC UBA domain belongs to an ancient and distinct subgroup of the UBA family. In contrast to the situation with budding yeast, fission yeast cells devoid of NAC were not temperature sensitive. However, they displayed resistance to the amino...

The anti-apoptotic BAG3 protein is involved in BRAF inhibitor resistance in melanoma cells.

Science.gov (United States)

Guerriero, Luana; Palmieri, Giuseppe; De Marco, Margot; Cossu, Antonio; Remondelli, Paolo; Capunzo, Mario; Turco, Maria Caterina; Rosati, Alessandra

2017-10-06

BAG3 protein, a member of BAG family of co-chaperones, has a pro-survival role in several tumour types. BAG3 anti-apoptotic properties rely on its characteristic to bind several intracellular partners, thereby modulating crucial events such as apoptosis, differentiation, cell motility, and autophagy. In human melanomas, BAG3 positivity is correlated with the aggressiveness of the tumour cells and can sustain IKK-γ levels, allowing a sustained activation of NF-κB. Furthermore, BAG3 is able to modulate BRAFV600E levels and activity in thyroid carcinomas. BRAFV600E is the most frequent mutation detected in malignant melanomas and is targeted by Vemurafenib, a specific inhibitor found to be effective in the treatment of advanced melanoma. However, patients with BRAF-mutated melanoma may result insensitive ab initio or, mostly, develop acquired resistance to the treatment with this molecule. Here we show that BAG3 down-modulation interferes with BRAF levels in melanoma cells and sensitizes them to Vemurafenib treatment. Furthermore, the down-modulation of BAG3 protein in an in vitro model of acquired resistance to Vemurafenib can induce sensitization to the BRAFV600E specific inhibition by interfering with BRAF pathway through reduction of ERK phosphorylation, but also on parallel survival pathways. Future studies on BAG3 molecular interactions with key proteins responsible of acquired BRAF inhibitor resistance may represent a promising field for novel multi-drugs treatment design.

Conservation and divergence of C-terminal domain structure in the retinoblastoma protein family

Energy Technology Data Exchange (ETDEWEB)

Liban, Tyler J.; Medina, Edgar M.; Tripathi, Sarvind; Sengupta, Satyaki; Henry, R. William; Buchler, Nicolas E.; Rubin, Seth M. (UCSC); (Duke); (MSU)

2017-04-24

The retinoblastoma protein (Rb) and the homologous pocket proteins p107 and p130 negatively regulate cell proliferation by binding and inhibiting members of the E2F transcription factor family. The structural features that distinguish Rb from other pocket proteins have been unclear but are critical for understanding their functional diversity and determining why Rb has unique tumor suppressor activities. We describe here important differences in how the Rb and p107 C-terminal domains (CTDs) associate with the coiled-coil and marked-box domains (CMs) of E2Fs. We find that although CTD–CM binding is conserved across protein families, Rb and p107 CTDs show clear preferences for different E2Fs. A crystal structure of the p107 CTD bound to E2F5 and its dimer partner DP1 reveals the molecular basis for pocket protein–E2F binding specificity and how cyclin-dependent kinases differentially regulate pocket proteins through CTD phosphorylation. Our structural and biochemical data together with phylogenetic analyses of Rb and E2F proteins support the conclusion that Rb evolved specific structural motifs that confer its unique capacity to bind with high affinity those E2Fs that are the most potent activators of the cell cycle.

The Sorcerer II Global Ocean Sampling Expedition: Expanding theUniverse of Protein Families

Energy Technology Data Exchange (ETDEWEB)

Yooseph, Shibu; Sutton, Granger; Rusch, Douglas B.; Halpern,Aaron L.; Williamson, Shannon J.; Remington, Karin; Eisen, Jonathan A.; Heidelberg, Karla B.; Manning, Gerard; Li, Weizhong; Jaroszewski, Lukasz; Cieplak, Piotr; Miller, Christopher S.; Li, Huiying; Mashiyama, Susan T.; Joachimiak, Marcin P.; van Belle, Christopher; Chandonia, John-Marc; Soergel, David A.; Zhai, Yufeng; Natarajan, Kannan; Lee, Shaun; Raphael,Benjamin J.; Bafna, Vineet; Friedman, Robert; Brenner, Steven E.; Godzik,Adam; Eisenberg, David; Dixon, Jack E.; Taylor, Susan S.; Strausberg,Robert L.; Frazier, Marvin; Venter, J.Craig

2006-03-23

Metagenomics projects based on shotgun sequencing of populations of micro-organisms yield insight into protein families. We used sequence similarity clustering to explore proteins with a comprehensive dataset consisting of sequences from available databases together with 6.12 million proteins predicted from an assembly of 7.7 million Global Ocean Sampling (GOS) sequences. The GOS dataset covers nearly all known prokaryotic protein families. A total of 3,995 medium- and large-sized clusters consisting of only GOS sequences are identified, out of which 1,700 have no detectable homology to known families. The GOS-only clusters contain a higher than expected proportion of sequences of viral origin, thus reflecting a poor sampling of viral diversity until now. Protein domain distributions in the GOS dataset and current protein databases show distinct biases. Several protein domains that were previously categorized as kingdom specific are shown to have GOS examples in other kingdoms. About 6,000 sequences (ORFans) from the literature that heretofore lacked similarity to known proteins have matches in the GOS data. The GOS dataset is also used to improve remote homology detection. Overall, besides nearly doubling the number of current proteins, the predicted GOS proteins also add a great deal of diversity to known protein families and shed light on their evolution. These observations are illustrated using several protein families, including phosphatases, proteases, ultraviolet-irradiation DNA damage repair enzymes, glutamine synthetase, and RuBisCO. The diversity added by GOS data has implications for choosing targets for experimental structure characterization as part of structural genomics efforts. Our analysis indicates that new families are being discovered at a rate that is linear or almost linear with the addition of new sequences, implying that we are still far from discovering all protein families in nature.

The Sorcerer II Global Ocean Sampling expedition: expanding the universe of protein families.

Science.gov (United States)

Yooseph, Shibu; Sutton, Granger; Rusch, Douglas B; Halpern, Aaron L; Williamson, Shannon J; Remington, Karin; Eisen, Jonathan A; Heidelberg, Karla B; Manning, Gerard; Li, Weizhong; Jaroszewski, Lukasz; Cieplak, Piotr; Miller, Christopher S; Li, Huiying; Mashiyama, Susan T; Joachimiak, Marcin P; van Belle, Christopher; Chandonia, John-Marc; Soergel, David A; Zhai, Yufeng; Natarajan, Kannan; Lee, Shaun; Raphael, Benjamin J; Bafna, Vineet; Friedman, Robert; Brenner, Steven E; Godzik, Adam; Eisenberg, David; Dixon, Jack E; Taylor, Susan S; Strausberg, Robert L; Frazier, Marvin; Venter, J Craig

2007-03-01

Metagenomics projects based on shotgun sequencing of populations of micro-organisms yield insight into protein families. We used sequence similarity clustering to explore proteins with a comprehensive dataset consisting of sequences from available databases together with 6.12 million proteins predicted from an assembly of 7.7 million Global Ocean Sampling (GOS) sequences. The GOS dataset covers nearly all known prokaryotic protein families. A total of 3,995 medium- and large-sized clusters consisting of only GOS sequences are identified, out of which 1,700 have no detectable homology to known families. The GOS-only clusters contain a higher than expected proportion of sequences of viral origin, thus reflecting a poor sampling of viral diversity until now. Protein domain distributions in the GOS dataset and current protein databases show distinct biases. Several protein domains that were previously categorized as kingdom specific are shown to have GOS examples in other kingdoms. About 6,000 sequences (ORFans) from the literature that heretofore lacked similarity to known proteins have matches in the GOS data. The GOS dataset is also used to improve remote homology detection. Overall, besides nearly doubling the number of current proteins, the predicted GOS proteins also add a great deal of diversity to known protein families and shed light on their evolution. These observations are illustrated using several protein families, including phosphatases, proteases, ultraviolet-irradiation DNA damage repair enzymes, glutamine synthetase, and RuBisCO. The diversity added by GOS data has implications for choosing targets for experimental structure characterization as part of structural genomics efforts. Our analysis indicates that new families are being discovered at a rate that is linear or almost linear with the addition of new sequences, implying that we are still far from discovering all protein families in nature.

The Sorcerer II Global Ocean Sampling expedition: expanding the universe of protein families.

Directory of Open Access Journals (Sweden)

Shibu Yooseph

2007-03-01

Full Text Available Metagenomics projects based on shotgun sequencing of populations of micro-organisms yield insight into protein families. We used sequence similarity clustering to explore proteins with a comprehensive dataset consisting of sequences from available databases together with 6.12 million proteins predicted from an assembly of 7.7 million Global Ocean Sampling (GOS sequences. The GOS dataset covers nearly all known prokaryotic protein families. A total of 3,995 medium- and large-sized clusters consisting of only GOS sequences are identified, out of which 1,700 have no detectable homology to known families. The GOS-only clusters contain a higher than expected proportion of sequences of viral origin, thus reflecting a poor sampling of viral diversity until now. Protein domain distributions in the GOS dataset and current protein databases show distinct biases. Several protein domains that were previously categorized as kingdom specific are shown to have GOS examples in other kingdoms. About 6,000 sequences (ORFans from the literature that heretofore lacked similarity to known proteins have matches in the GOS data. The GOS dataset is also used to improve remote homology detection. Overall, besides nearly doubling the number of current proteins, the predicted GOS proteins also add a great deal of diversity to known protein families and shed light on their evolution. These observations are illustrated using several protein families, including phosphatases, proteases, ultraviolet-irradiation DNA damage repair enzymes, glutamine synthetase, and RuBisCO. The diversity added by GOS data has implications for choosing targets for experimental structure characterization as part of structural genomics efforts. Our analysis indicates that new families are being discovered at a rate that is linear or almost linear with the addition of new sequences, implying that we are still far from discovering all protein families in nature.

Trends in global warming and evolution of matrix protein 2 family from influenza A virus.

Science.gov (United States)

Yan, Shao-Min; Wu, Guang

2009-12-01

The global warming is an important factor affecting the biological evolution, and the influenza is an important disease that threatens humans with possible epidemics or pandemics. In this study, we attempted to analyze the trends in global warming and evolution of matrix protein 2 family from influenza A virus, because this protein is a target of anti-flu drug, and its mutation would have significant effect on the resistance to anti-flu drugs. The evolution of matrix protein 2 of influenza A virus from 1959 to 2008 was defined using the unpredictable portion of amino-acid pair predictability. Then the trend in this evolution was compared with the trend in the global temperature, the temperature in north and south hemispheres, and the temperature in influenza A virus sampling site, and species carrying influenza A virus. The results showed the similar trends in global warming and in evolution of M2 proteins although we could not correlate them at this stage of study. The study suggested the potential impact of global warming on the evolution of proteins from influenza A virus.

Family-based transmission disequilibrium test (TDT) and case-control association studies reveal surfactant protein A (SP-A) susceptibility alleles for respiratory distress syndrome (RDS) and possible race differences

NARCIS (Netherlands)

Floros, J.; Fan, R.; Matthews, A.; DiAngelo, S.; Luo, J.; Nielsen, H.; Dunn, M.; Gewolb, I. H.; Koppe, J.; Van Sonderen, L.; Farri-Kostopoulos, L.; Tzaki, M.; Rämet, M.; Merrill, J.

2001-01-01

A key cause of respiratory distress syndrome (RDS) in the prematurely born infant is deficiency of pulmonary surfactant, a lipoprotein complex. Both low levels of surfactant protein A (SP-A) and SP-A alleles have been associated with RDS. Using the candidate gene approach, we performed family-based

Protein thermostability prediction within homologous families using temperature-dependent statistical potentials.

Directory of Open Access Journals (Sweden)

Fabrizio Pucci

Full Text Available The ability to rationally modify targeted physical and biological features of a protein of interest holds promise in numerous academic and industrial applications and paves the way towards de novo protein design. In particular, bioprocesses that utilize the remarkable properties of enzymes would often benefit from mutants that remain active at temperatures that are either higher or lower than the physiological temperature, while maintaining the biological activity. Many in silico methods have been developed in recent years for predicting the thermodynamic stability of mutant proteins, but very few have focused on thermostability. To bridge this gap, we developed an algorithm for predicting the best descriptor of thermostability, namely the melting temperature Tm, from the protein's sequence and structure. Our method is applicable when the Tm of proteins homologous to the target protein are known. It is based on the design of several temperature-dependent statistical potentials, derived from datasets consisting of either mesostable or thermostable proteins. Linear combinations of these potentials have been shown to yield an estimation of the protein folding free energies at low and high temperatures, and the difference of these energies, a prediction of the melting temperature. This particular construction, that distinguishes between the interactions that contribute more than others to the stability at high temperatures and those that are more stabilizing at low T, gives better performances compared to the standard approach based on T-independent potentials which predict the thermal resistance from the thermodynamic stability. Our method has been tested on 45 proteins of known Tm that belong to 11 homologous families. The standard deviation between experimental and predicted Tm's is equal to 13.6°C in cross validation, and decreases to 8.3°C if the 6 worst predicted proteins are excluded. Possible extensions of our approach are discussed.

Receptor oligomerization in family B1 of G-protein-coupled receptors

DEFF Research Database (Denmark)

Roed, Sarah Norklit; Ørgaard, Anne; Jørgensen, Rasmus

2012-01-01

, the glucagon receptor, and the receptors for parathyroid hormone (PTHR1 and PTHR2). The dysregulation of several family B1 receptors is involved in diseases, such as diabetes, chronic inflammation, and osteoporosis which underlines the pathophysiological importance of this GPCR subfamily. In spite of this......, investigation of family B1 receptor oligomerization and especially its pharmacological importance is still at an early stage. Even though GPCR oligomerization is a well-established phenomenon, there is a need for more investigations providing a direct link between these interactions and receptor functionality......The superfamily of the seven transmembrane G-protein-coupled receptors (7TM/GPCRs) is the largest family of membrane-associated receptors. GPCRs are involved in the pathophysiology of numerous human diseases, and they constitute an estimated 30-40% of all drug targets. During the last two decades...

F2 screen, inheritance and cross-resistance of field-derived Vip3A resistance in Spodoptera frugiperda (Lepidoptera: Noctuidae) collected from Louisiana, USA.

Science.gov (United States)

Yang, Fei; Morsello, Shannon; Head, Graham P; Sansone, Chris; Huang, Fangneng; Gilreath, Ryan T; Kerns, David L

2017-11-28

Fall armyworm, Spodoptera frugiperda, is a target pest of the Vip3A protein used in pyramided Bt corn and cotton in the USA. In this study, we provide the first documentation of a resistance allele conferring Vip3A resistance in a field-derived population of S. frugiperda from the USA, and characterize its inheritance and cross-resistance. An F 2 screen with 104 two-parent families generated from a field collection of S. frugiperda in Louisiana, USA, resulted in one family carrying a Vip3A resistance allele. The Vip3A-resistant strain (RR) derived from the two-parent family showed a high level of resistance to Vip3A in both diet and whole-plant bioassays, with a resistance ratio of >632.0-fold relative to a susceptible population (SS) based on diet-overlay bioassays. The inheritance of Vip3A resistance was monogenic, autosomal and recessive. Furthermore, the Vip3A resistance conferred no cross-resistance to Cry1F, Cry2Ab2 or Cry2Ae purified proteins, with resistance ratios of 3.5, 5.0 and 1.1, respectively. These findings provide valuable information for characterizing Vip3A resistance, resistance monitoring, and developing effective resistance management strategies for the sustainable use of the Vip3A technology. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Improved annotation of antibiotic resistance determinants reveals microbial resistomes cluster by ecology.

Science.gov (United States)

Gibson, Molly K; Forsberg, Kevin J; Dantas, Gautam

2015-01-01

Antibiotic resistance is a dire clinical problem with important ecological dimensions. While antibiotic resistance in human pathogens continues to rise at alarming rates, the impact of environmental resistance on human health is still unclear. To investigate the relationship between human-associated and environmental resistomes, we analyzed functional metagenomic selections for resistance against 18 clinically relevant antibiotics from soil and human gut microbiota as well as a set of multidrug-resistant cultured soil isolates. These analyses were enabled by Resfams, a new curated database of protein families and associated highly precise and accurate profile hidden Markov models, confirmed for antibiotic resistance function and organized by ontology. We demonstrate that the antibiotic resistance functions that give rise to the resistance profiles observed in environmental and human-associated microbial communities significantly differ between ecologies. Antibiotic resistance functions that most discriminate between ecologies provide resistance to β-lactams and tetracyclines, two of the most widely used classes of antibiotics in the clinic and agriculture. We also analyzed the antibiotic resistance gene composition of over 6000 sequenced microbial genomes, revealing significant enrichment of resistance functions by both ecology and phylogeny. Together, our results indicate that environmental and human-associated microbial communities harbor distinct resistance genes, suggesting that antibiotic resistance functions are largely constrained by ecology.

Nonlinear analysis of sequence symmetry of beta-trefoil family proteins

Energy Technology Data Exchange (ETDEWEB)

Li Mingfeng [Biomolecular Physics and Modeling Group, Department of Physics, Huazhong University of Science and Technology, Wuhan 430074, Hubei (China); Huang Yanzhao [Biomolecular Physics and Modeling Group, Department of Physics, Huazhong University of Science and Technology, Wuhan 430074, Hubei (China); Xu Ruizhen [Biomolecular Physics and Modeling Group, Department of Physics, Huazhong University of Science and Technology, Wuhan 430074, Hubei (China); Xiao Yi [Biomolecular Physics and Modeling Group, Department of Physics, Huazhong University of Science and Technology, Wuhan 430074, Hubei (China)]. E-mail: yxiao@mail.hust.edu.cn

2005-07-01

The tertiary structures of proteins of beta-trefoil family have three-fold quasi-symmetry while their amino acid sequences appear almost at random. In the present paper we show that these amino acid sequences have hidden symmetries in fact and furthermore the degrees of these hidden symmetries are the same as those of their tertiary structures. We shall present a modified recurrence plot to reveal hidden symmetries in protein sequences. Our results can explain the contradiction in sequence-structure relations of proteins of beta-trefoil family.

GCK-MODY diabetes as a protein misfolding disease: the mutation R275C promotes protein misfolding, self-association and cellular degradation.

Science.gov (United States)

Negahdar, Maria; Aukrust, Ingvild; Molnes, Janne; Solheim, Marie H; Johansson, Bente B; Sagen, Jørn V; Dahl-Jørgensen, Knut; Kulkarni, Rohit N; Søvik, Oddmund; Flatmark, Torgeir; Njølstad, Pål R; Bjørkhaug, Lise

2014-01-25

GCK-MODY, dominantly inherited mild hyperglycemia, is associated with more than 600 mutations in the glucokinase gene. Different molecular mechanisms have been shown to explain GCK-MODY. Here, we report a Pakistani family harboring the glucokinase mutation c.823C>T (p.R275C). The recombinant and in cellulo expressed mutant pancreatic enzyme revealed slightly increased enzyme activity (kcat) and normal affinity for α-D-glucose, and resistance to limited proteolysis by trypsin comparable with wild-type. When stably expressed in HEK293 cells and MIN6 β-cells (at different levels), the mutant protein appeared misfolded and unstable with a propensity to form dimers and aggregates. Its degradation rate was increased, involving the lysosomal and proteasomal quality control systems. On mutation, a hydrogen bond between the R275 side-chain and the carbonyl oxygen of D267 is broken, destabilizing the F260-L271 loop structure and the protein. This promotes the formation of dimers/aggregates and suggests that an increased cellular degradation is the molecular mechanism by which R275C causes GCK-MODY. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Methyl-CpG-Binding Protein (MBD) Family: Epigenomic Read-Outs Functions and Roles in Tumorigenesis and Psychiatric Diseases.

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Gigek, Carolina Oliveira; Chen, Elizabeth Suchi; Smith, Marilia Arruda Cardoso

2016-01-01

Epigenetics is the study of the heritable changes on gene expression that are responsible for the regulation of development and that have an impact on several diseases. However, it is of equal importance to understand how epigenetic machinery works. DNA methylation is the most studied epigenetic mark and is generally associated with the regulation of gene expression through the repression of promoter activity and by affecting genome stability. Therefore, the ability of the cell to interpret correct methylation marks and/or the correct interpretation of methylation plays a role in many diseases. The major family of proteins that bind methylated DNA is the methyl-CpG binding domain proteins, or the MBDs. Here, we discuss the structure that makes these proteins a family, the main functions and interactions of all protein family members and their role in human disease such as psychiatric disorders and cancer. © 2015 Wiley Periodicals, Inc.

Effect of Resistance Exercise Training Associated with Skeletal Muscle Hypertrophy on Serum Pro-Inflammatory Cytokines in STZ-induced Diabetes

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Mahdieh Molanouri Shamsi

2016-06-01

Full Text Available Skeletal muscle atrophy is associated with type 1 diabetes. Effects of resistance exercise training associated with skeletal muscle hypertrophy on serum inflammatory cytokines was exactly not clarified. Protein levels of inflammatory cytokines IL-6, TNF-α, and interleukin-1beta (IL-1β in serum of healthy and streptozotocin (STZ- induced diabetic rats subjected to resistance exercise training were assessed in this study. Rats were divided into the control, training, control diabetic and diabetic training groups. Training groups performed the resistance training consisted of climbing a 1 m ladder with increasing weight added to the tail. Proteins levels of IL-6, TNF-α and IL-1β in serum were measured by the ELIZA method. The results of this study indicated that resistance training induced skeletal muscle hypertrophy in diabetic samples (P<0.05. Also, Resistance training decrease IL-6 protein levels in serum. Inflammatory cytokines could act as stress factors in diabetes. It seems that this kind of exercise training individually could not change cytokines levels in serum.

Structural insights and ab initio sequencing within the DING proteins family

International Nuclear Information System (INIS)

Elias, Mikael; Liebschner, Dorothee; Gotthard, Guillaume; Chabriere, Eric

2011-01-01

DING proteins constitute a recently discovered protein family that is ubiquitous in eukaryotes. The structural insights and the physiological involvements of these intriguing proteins are hereby deciphered. DING proteins constitute an intriguing family of phosphate-binding proteins that was identified in a wide range of organisms, from prokaryotes and archae to eukaryotes. Despite their seemingly ubiquitous occurrence in eukaryotes, their encoding genes are missing from sequenced genomes. Such a lack has considerably hampered functional studies. In humans, these proteins have been related to several diseases, like atherosclerosis, kidney stones, inflammation processes and HIV inhibition. The human phosphate binding protein is a human representative of the DING family that was serendipitously discovered from human plasma. An original approach was developed to determine ab initio the complete and exact sequence of this 38 kDa protein by utilizing mass spectrometry and X-ray data in tandem. Taking advantage of this first complete eukaryotic DING sequence, a immunohistochemistry study was undertaken to check the presence of DING proteins in various mice tissues, revealing that these proteins are widely expressed. Finally, the structure of a bacterial representative from Pseudomonas fluorescens was solved at sub-angstrom resolution, allowing the molecular mechanism of the phosphate binding in these high-affinity proteins to be elucidated

Structural insights and ab initio sequencing within the DING proteins family

Energy Technology Data Exchange (ETDEWEB)

Elias, Mikael, E-mail: mikael.elias@weizmann.ac.il [Weizmann Institute of Science, Rehovot (Israel); Liebschner, Dorothee [CRM2, Nancy Université (France); Gotthard, Guillaume; Chabriere, Eric [AFMB, Université Aix-Marseille II (France)

2011-01-01

DING proteins constitute a recently discovered protein family that is ubiquitous in eukaryotes. The structural insights and the physiological involvements of these intriguing proteins are hereby deciphered. DING proteins constitute an intriguing family of phosphate-binding proteins that was identified in a wide range of organisms, from prokaryotes and archae to eukaryotes. Despite their seemingly ubiquitous occurrence in eukaryotes, their encoding genes are missing from sequenced genomes. Such a lack has considerably hampered functional studies. In humans, these proteins have been related to several diseases, like atherosclerosis, kidney stones, inflammation processes and HIV inhibition. The human phosphate binding protein is a human representative of the DING family that was serendipitously discovered from human plasma. An original approach was developed to determine ab initio the complete and exact sequence of this 38 kDa protein by utilizing mass spectrometry and X-ray data in tandem. Taking advantage of this first complete eukaryotic DING sequence, a immunohistochemistry study was undertaken to check the presence of DING proteins in various mice tissues, revealing that these proteins are widely expressed. Finally, the structure of a bacterial representative from Pseudomonas fluorescens was solved at sub-angstrom resolution, allowing the molecular mechanism of the phosphate binding in these high-affinity proteins to be elucidated.

Expression of multidrug resistance-related protein (MRP-1), lung resistance-related protein (LRP) and topoisomerase-II (TOPO-II) in Wilms' tumor: immunohistochemical study using TMA methodology.

Science.gov (United States)

Fridman, Eduard; Skarda, Jozef; Pinthus, Jonatan H; Ramon, Jonathan; Mor, Yoran

2008-06-01

MRP-1, LRP and TOPO-II are all associated with protection of the cells from the adverse effects of various chemotherapeutics. The aim of this study was to measure the expression of these proteins in Wilms' tumor (WT). TMA block was constructed from 14 samples of WT's and from xenografts derived from them. Sections of the TMA were used for immunostaining against MRP-1, LRP and TOPO-IIa. All normal kidneys expressed MRP-1 but were either weakly or negatively stained for LRP and TOPO-IIa. In WT samples, MRP-1 was universally expressed, exclusively in the tubular component, while there was no expression of LRP and TOPO-IIa showed heterogeneous distribution. The xenografts varied in their MRP-1 and TOPO-IIa expression and exhibited weak/negative staining of LRP. This study shows that although all the proteins evaluated, had different expression patterns in the tumor samples, the most prominent changes in expression were found for MRP-1. The exact clinical implications of these changes in expression and their relevance to the resistance of these tumors to chemotherapy requires further investigation. The finding of different expression profiles for the multidrug resistance proteins in the original WT's and their xenografts suggests that the results of animal cancer models may be difficult to interpret.

Macrolide Resistance Mediated by a Bifidobacterium breve Membrane Protein

OpenAIRE

Margolles, Abelardo; Moreno, José Antonio; van Sinderen, Douwe; de los Reyes-Gavilán, Clara G.

2005-01-01

A gene coding for a hypothetical membrane protein from Bifidobacterium breve was expressed in Lactococcus lactis. Immunoblotting demonstrated that this protein is located in the membrane. Phenotypical changes in sensitivity towards 21 antibiotics were determined. The membrane protein-expressing cells showed higher levels of resistance to several macrolides.

The DExH/D protein family database.

Science.gov (United States)

Jankowsky, E; Jankowsky, A

2000-01-01

DExH/D proteins are essential for all aspects of cellular RNA metabolism and processing, in the replication of many viruses and in DNA replication. DExH/D proteins are subject to current biological, biochemical and biophysical research which provides a continuous wealth of data. The DExH/D protein family database compiles this information and makes it available over the WWW (http://www.columbia.edu/ ej67/dbhome.htm ). The database can be fully searched by text based queries, facilitating fast access to specific information about this important class of enzymes.

Familial short fifth metacarpals and insulin resistance

International Nuclear Information System (INIS)

Hyari, Muwafag; Hamamy, Hanan; Barham, Muries; Ajlouni, Kamel; Al-Hadidy, Azmy

2006-01-01

Very few reports on the phenotype of short fifth metacarpals have been published in the medical literature. We report a Jordanian family in which three sisters aged 15, 13 and 8 years revealed bilateral shortening of the fifth fingers and radiological shortening of the fifth metacarpals. The father had unilateral short fifth metacarpal. The elder two sisters, their father as well as their brother and another sister manifested insulin resistance. Spherocytosis was diagnosed in one of the girls and her father. The parents are non-consanguineous. This constellation of findings has not been previously reported and could point to the presence of two disorders segregating in the family or to a novel syndrome with autosomal dominant inheritance and variable expressivity. (orig.)

Clustering evolving proteins into homologous families.

Science.gov (United States)

Chan, Cheong Xin; Mahbob, Maisarah; Ragan, Mark A

2013-04-08

Clustering sequences into groups of putative homologs (families) is a critical first step in many areas of comparative biology and bioinformatics. The performance of clustering approaches in delineating biologically meaningful families depends strongly on characteristics of the data, including content bias and degree of divergence. New, highly scalable methods have recently been introduced to cluster the very large datasets being generated by next-generation sequencing technologies. However, there has been little systematic investigation of how characteristics of the data impact the performance of these approaches. Using clusters from a manually curated dataset as reference, we examined the performance of a widely used graph-based Markov clustering algorithm (MCL) and a greedy heuristic approach (UCLUST) in delineating protein families coded by three sets of bacterial genomes of different G+C content. Both MCL and UCLUST generated clusters that are comparable to the reference sets at specific parameter settings, although UCLUST tends to under-cluster compositionally biased sequences (G+C content 33% and 66%). Using simulated data, we sought to assess the individual effects of sequence divergence, rate heterogeneity, and underlying G+C content. Performance decreased with increasing sequence divergence, decreasing among-site rate variation, and increasing G+C bias. Two MCL-based methods recovered the simulated families more accurately than did UCLUST. MCL using local alignment distances is more robust across the investigated range of sequence features than are greedy heuristics using distances based on global alignment. Our results demonstrate that sequence divergence, rate heterogeneity and content bias can individually and in combination affect the accuracy with which MCL and UCLUST can recover homologous protein families. For application to data that are more divergent, and exhibit higher among-site rate variation and/or content bias, MCL may often be the better

Downregulation and Mutation of a Cadherin Gene Associated with Cry1Ac Resistance in the Asian Corn Borer, Ostrinia furnacalis (Guenée

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Tingting Jin

2014-09-01

Full Text Available Development of resistance in target pests is a major threat to long-term use of transgenic crops expressing Bacillus thuringiensis (Bt Cry toxins. To manage and/or delay the evolution of resistance in target insects through the implementation of effective strategies, it is essential to understand the basis of resistance. One of the most important mechanisms of insect resistance to Bt crops is the alteration of the interactions between Cry toxins and their receptors in the midgut. A Cry1Ac-selected strain of Asian corn borer (ACB, Ostrinia furnacalis, a key pest of maize in China, evolved three mutant alleles of a cadherin-like protein (OfCAD (MPR-r1, MPR-r2 and MPR-r3, which mapped within the toxin-binding region (TBR. Each of the three mutant alleles possessed two or three amino acid substitutions in this region, especially Thr1457→Ser. In highly resistant larvae (ACB-Ac200, MPR-r2 had a 26-amino acid residue deletion in the TBR, which resulted in reduced binding of Cry1Ac compared to the MPR from the susceptible strain, suggesting that the number of amino acid deletions influences the level of resistance. Furthermore, downregulation of OfCAD gene (ofcad transcription was observed in the Cry1Ac resistant strain, ACB-Ac24, suggesting that Cry1Ac resistance in ACB is associated with the downregulation of the transcript levels of the cadherin-like protein gene. The OfCAD identified from ACB exhibited a high degree of similarity to other members of the cadherin super-family in lepidopteran species.

Candidate gene association analyses for ketosis resistance in Holsteins.

Science.gov (United States)

Kroezen, V; Schenkel, F S; Miglior, F; Baes, C F; Squires, E J

2018-06-01

High-yielding dairy cattle are susceptible to ketosis, a metabolic disease that negatively affects the health, fertility, and milk production of the cow. Interest in breeding for more robust dairy cattle with improved resistance to disease is global; however, genetic evaluations for ketosis would benefit from the additional information provided by genetic markers. Candidate genes that are proposed to have a biological role in the pathogenesis of ketosis were investigated in silico and a custom panel of 998 putative single nucleotide polymorphism (SNP) markers was developed. The objective of this study was to test the associations of these new markers with deregressed estimated breeding values (EBV) for ketosis. A sample of 653 Canadian Holstein cows that had been previously genotyped with a medium-density SNP chip were regenotyped with the custom panel. The EBV for ketosis in first and later lactations were obtained for each animal and deregressed for use as pseudo-phenotypes for association analyses. Results of the mixed inheritance model for single SNP association analyses suggested 15 markers in 6 unique candidate genes were associated with the studied trait. Genes encoding proteins involved in metabolic processes, including the synthesis and degradation of fatty acids and ketone bodies, gluconeogenesis, lipid mobilization, and the citric acid cycle, were identified to contain SNP associated with ketosis resistance. This work confirmed the presence of previously described quantitative trait loci for dairy cattle, suggested novel markers for ketosis-resistance, and provided insight into the underlying biology of this disease. Copyright © 2018 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Linkage disequilibrium at the APA insecticidal seed protein locus of common bean (Phaseolus vulgaris L.).

Science.gov (United States)

Blair, Matthew W; Prieto, Sergio; Díaz, Lucy M; Buendía, Héctor F; Cardona, César

2010-04-29

An interesting seed protein family with a role in preventing insect herbivory is the multi-gene, APA family encoding the alpha-amylase inhibitor, phytohemagglutinin and arcelin proteins of common bean (Phaseolus vulgaris). Variability for this gene family exists and has been exploited to breed for insect resistance. For example, the arcelin locus has been successfully transferred from wild to cultivated common bean genotypes to provide resistance against the bruchid species Zabrotes subfasciatus although the process has been hampered by a lack of genetic tools for and understanding about the locus. In this study, we analyzed linkage disequilibrium (LD) between microsatellite markers at the APA locus and bruchid resistance in a germplasm survey of 105 resistant and susceptible genotypes and compared this with LD in other parts of the genome. Microsatellite allele diversity was found to vary with each of the eight APA-linked markers analyzed, and two markers within the APA locus were found to be diagnostic for bruchid resistance or susceptibility and for the different arcelin alleles inherited from the wild accessions. Arc1 was found to provide higher levels of resistance than Arc5 and the markers in the APA locus were highly associated with resistance showing that introgression of this gene-family from wild beans provides resistance in cultivated beans. LD around the APA locus was found to be intermediate compared to other regions of the genome and the highest LD was found within the APA locus itself for example between the markers PV-atct001 and PV-ag004. We found the APA locus to be an important genetic determinant of bruchid resistance and also found that LD existed mostly within the APA locus but not beyond it. Moderate LD was also found for some other regions of the genome perhaps related to domestication genes. The LD pattern may reflect the introgression of arcelin from the wild into the cultivated background through breeding. LD and association studies for

Structure of the GH1 domain of guanylate kinase-associated protein from Rattus norvegicus

International Nuclear Information System (INIS)

Tong, Junsen; Yang, Huiseon; Eom, Soo Hyun; Chun, ChangJu; Im, Young Jun

2014-01-01

Graphical abstract: - Highlights: • The crystal structure of GKAP homology domain 1 (GH1) was determined. • GKAP GH1 is a three-helix bundle connected by short flexible loops. • The predicted helix α4 associates weakly with the helix α3, suggesting dynamic nature of the GH1 domain. - Abstract: Guanylate-kinase-associated protein (GKAP) is a scaffolding protein that links NMDA receptor-PSD-95 to Shank–Homer complexes by protein–protein interactions at the synaptic junction. GKAP family proteins are characterized by the presence of a C-terminal conserved GKAP homology domain 1 (GH1) of unknown structure and function. In this study, crystal structure of the GH1 domain of GKAP from Rattus norvegicus was determined in fusion with an N-terminal maltose-binding protein at 2.0 Å resolution. The structure of GKAP GH1 displays a three-helix bundle connected by short flexible loops. The predicted helix α4 which was not visible in the crystal structure associates weakly with the helix α3 suggesting dynamic nature of the GH1 domain. The strict conservation of GH1 domain across GKAP family members and the lack of a catalytic active site required for enzyme activity imply that the GH1 domain might serve as a protein–protein interaction module for the synaptic protein clustering

Structure of the GH1 domain of guanylate kinase-associated protein from Rattus norvegicus

Energy Technology Data Exchange (ETDEWEB)

Tong, Junsen; Yang, Huiseon [College of Pharmacy, Chonnam National University, Gwangju 500-757 (Korea, Republic of); Eom, Soo Hyun [School of Life Sciences, Steitz Center for Structural Biology, and Department of Chemistry, Gwangju Institute of Science and Technology, Gwangju 500-712 (Korea, Republic of); Chun, ChangJu, E-mail: cchun1130@jnu.ac.kr [College of Pharmacy, Chonnam National University, Gwangju 500-757 (Korea, Republic of); Im, Young Jun, E-mail: imyoungjun@jnu.ac.kr [College of Pharmacy, Chonnam National University, Gwangju 500-757 (Korea, Republic of)

2014-09-12

Graphical abstract: - Highlights: • The crystal structure of GKAP homology domain 1 (GH1) was determined. • GKAP GH1 is a three-helix bundle connected by short flexible loops. • The predicted helix α4 associates weakly with the helix α3, suggesting dynamic nature of the GH1 domain. - Abstract: Guanylate-kinase-associated protein (GKAP) is a scaffolding protein that links NMDA receptor-PSD-95 to Shank–Homer complexes by protein–protein interactions at the synaptic junction. GKAP family proteins are characterized by the presence of a C-terminal conserved GKAP homology domain 1 (GH1) of unknown structure and function. In this study, crystal structure of the GH1 domain of GKAP from Rattus norvegicus was determined in fusion with an N-terminal maltose-binding protein at 2.0 Å resolution. The structure of GKAP GH1 displays a three-helix bundle connected by short flexible loops. The predicted helix α4 which was not visible in the crystal structure associates weakly with the helix α3 suggesting dynamic nature of the GH1 domain. The strict conservation of GH1 domain across GKAP family members and the lack of a catalytic active site required for enzyme activity imply that the GH1 domain might serve as a protein–protein interaction module for the synaptic protein clustering.

Sifting through genomes with iterative-sequence clustering produces a large, phylogenetically diverse protein-family resource.

Science.gov (United States)

Sharpton, Thomas J; Jospin, Guillaume; Wu, Dongying; Langille, Morgan G I; Pollard, Katherine S; Eisen, Jonathan A

2012-10-13

New computational resources are needed to manage the increasing volume of biological data from genome sequencing projects. One fundamental challenge is the ability to maintain a complete and current catalog of protein diversity. We developed a new approach for the identification of protein families that focuses on the rapid discovery of homologous protein sequences. We implemented fully automated and high-throughput procedures to de novo cluster proteins into families based upon global alignment similarity. Our approach employs an iterative clustering strategy in which homologs of known families are sifted out of the search for new families. The resulting reduction in computational complexity enables us to rapidly identify novel protein families found in new genomes and to perform efficient, automated updates that keep pace with genome sequencing. We refer to protein families identified through this approach as "Sifting Families," or SFams. Our analysis of ~10.5 million protein sequences from 2,928 genomes identified 436,360 SFams, many of which are not represented in other protein family databases. We validated the quality of SFam clustering through statistical as well as network topology-based analyses. We describe the rapid identification of SFams and demonstrate how they can be used to annotate genomes and metagenomes. The SFam database catalogs protein-family quality metrics, multiple sequence alignments, hidden Markov models, and phylogenetic trees. Our source code and database are publicly available and will be subject to frequent updates (http://edhar.genomecenter.ucdavis.edu/sifting_families/).

An Exploration of Feminist Family Therapists' Resistance to and Collusion with Oppression

OpenAIRE

Goodwin, Annabelle Michelle

2011-01-01

In this study, I explore the ways in which feminist family therapists encourage exploration of, resistance to, and collusion with, oppression. I explore qualitatively the critical dialogues, both inner, and with others, that feminist family therapists employ to address oppressive systems. My research questions are: a. How do family therapists who identify as feminist describe how their feminist identities and ideas about feminism have evolved over time? b. How do feminist family therapists re...

Association of Serum Ferritin Levels with Metabolic Syndrome and Insulin Resistance.

Science.gov (United States)

Padwal, Meghana K; Murshid, Mohsin; Nirmale, Prachee; Melinkeri, R R

2015-09-01

The impact of CVDs and Type II DM is increasing over the last decade. It has been estimated that by 2025 their incidence will double. Ferritin is one of the key proteins regulating iron homeostasis and is a widely available clinical biomarker of iron status. Some studies suggest that prevalence of atherosclerosis and insulin resistance increases significantly with increasing serum ferritin. Metabolic syndrome is known to be associated with increased risk of atherosclerosis as well as insulin resistance. The present study was designed to explore the association of serum ferritin levels with metabolic syndrome and insulin resistance. The present study was prospective, cross sectional. The study protocol was approved by IEC. The study group consisted of 90 participants (50 cases of metabolic syndrome and 40 age and sex matched controls). Diagnosis of metabolic syndrome was done as per NCEP ATP III criteria. Estimation of serum Ferritin and Insulin was done by Chemiluminescence Immunoassay (CLIA) while Glucose by Glucose Oxidase and Peroxidase (GOD-POD) method. Insulin Resistance was calculated by HOMA IR score. Data obtained was statistically analysed by using student t-test. We found statistically significant rise in the levels of serum ferritin (p=syndrome as compared with controls. High serum ferritin levels though within normal range are significantly associated with both metabolic syndrome and insulin resistance.

The nuclear IκB family of proteins controls gene regulation and immune homeostasis.

Science.gov (United States)

MaruYama, Takashi

2015-10-01

The inhibitory IκB family of proteins is subdivided into two groups based on protein localization in the cytoplasm or in the nucleus. These proteins interact with NF-κB, a major transcription factor regulating the expression of many inflammatory cytokines, by modulating its transcriptional activity. However, nuclear IκB family proteins not only interact with NF-κB to change its transcriptional activity, but they also bind to chromatin and control gene expression. This review provides an overview of nuclear IκB family proteins and their role in immune homeostasis. Copyright © 2015 Elsevier B.V. All rights reserved.

Systematic mutagenesis of genes encoding predicted autotransported proteins of Burkholderia pseudomallei identifies factors mediating virulence in mice, net intracellular replication and a novel protein conferring serum resistance.

Directory of Open Access Journals (Sweden)

Natalie R Lazar Adler

Full Text Available Burkholderia pseudomallei is the causative agent of the severe tropical disease melioidosis, which commonly presents as sepsis. The B. pseudomallei K96243 genome encodes eleven predicted autotransporters, a diverse family of secreted and outer membrane proteins often associated with virulence. In a systematic study of these autotransporters, we constructed insertion mutants in each gene predicted to encode an autotransporter and assessed them for three pathogenesis-associated phenotypes: virulence in the BALB/c intra-peritoneal mouse melioidosis model, net intracellular replication in J774.2 murine macrophage-like cells and survival in 45% (v/v normal human serum. From the complete repertoire of eleven autotransporter mutants, we identified eight mutants which exhibited an increase in median lethal dose of 1 to 2-log10 compared to the isogenic parent strain (bcaA, boaA, boaB, bpaA, bpaC, bpaE, bpaF and bimA. Four mutants, all demonstrating attenuation for virulence, exhibited reduced net intracellular replication in J774.2 macrophage-like cells (bimA, boaB, bpaC and bpaE. A single mutant (bpaC was identified that exhibited significantly reduced serum survival compared to wild-type. The bpaC mutant, which demonstrated attenuation for virulence and net intracellular replication, was sensitive to complement-mediated killing via the classical and/or lectin pathway. Serum resistance was rescued by in trans complementation. Subsequently, we expressed recombinant proteins of the passenger domain of four predicted autotransporters representing each of the phenotypic groups identified: those attenuated for virulence (BcaA, those attenuated for virulence and net intracellular replication (BpaE, the BpaC mutant with defects in virulence, net intracellular replication and serum resistance and those displaying wild-type phenotypes (BatA. Only BcaA and BpaE elicited a strong IFN-γ response in a restimulation assay using whole blood from seropositive donors

Insulin resistance and associated factors: a cross-sectional study of bank employees.

Science.gov (United States)

Salaroli, Luciane Bresciani; Cattafesta, Monica; Molina, Maria Del Carmen Bisi; Zandonade, Eliana; Bissoli, Nazaré Souza

2017-04-01

Insulin resistance is characterized by the failure of target cells to respond to normal levels of circulating insulin, and this condition is related to cardiovascular disease. This study sought to evaluate the prevalence of insulin resistance and its association with markers of metabolic abnormalities and metabolic syndrome in bank employees. A cross-sectional study was performed on 498 working men and women aged ≥20 years old. The Homeostasis Model Assessment (HOMA-IR) was used to determine the presence of insulin resistance based on cut-off values of ≤2.71 for normal insulin levels and >2.71 for insulin resistance, as established for the adult Brazilian population. It was observed that the 52 (10.4%) overweight individuals with insulin resistance were 4.97 times (95%CI 1.31-18.83) more likely to have high HOMA-IR values than the normal-weight participants; among those who were obese, the likelihood increased to 17.87 (95%CI 4.36-73.21). Individuals with large waist circumferences were 3.27 times (95%CI 1.03-10.38) more likely to develop insulin resistance than those who were within normal parameters. The HOMA-IR values differed between subjects with and without metabolic syndrome, with values of 2.83±2.5 and 1.10±0.81 (p=0.001), respectively. The levels of insulin, ultrasensitive C-reactive protein and uric acid were also associated with insulin resistance. The prevalence of insulin resistance among bank employees is high, and insulin resistance is associated with and serves as a marker of metabolic syndrome. Cardiovascular disease and metabolic syndrome-associated metabolic abnormalities were observed, and insulin resistance may be a risk factor in this group of professionals.

Complete sequence of Fig fleck-associated virus, a novel member of the family Tymoviridae.

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Elbeaino, Toufic; Digiaro, Michele; Martelli, Giovanni P

2011-11-01

The complete nucleotide sequence and the genome organization were determined of a novel virus, tentatively named Fig fleck-associated virus (FFkaV). The viral genome is a positive-sense, single-stranded RNA 7046 nucleotides in size excluding the 3'-terminal poly(A) tract, and comprising two open reading frames. ORF1 encodes a polypeptide of 2161 amino acids (p240), which contains the signatures of replication-associated proteins and the coat protein cistron (p24) at its 3' end. ORF2 codes for a 461 amino acid protein (p50) identified as a putative movement proteins (MP). In phylogenetic trees constructed with sequences of the putative polymerase and CP proteins FFkaV consistently groups with members of the genus Maculavirus, family Tymoviridae. However, the genome organization diverges from that of the two completely sequenced maculaviruses, Grapevine fleck virus (GFkV) and Bombix mori Macula-like virus (BmMLV), as it exhibits a structure resembling that of Maize rayado fino virus (MRFV), the type species of the genus Marafivirus and of Olive latent virus 3 (OLV-3), an unclassified virus in the family Tymoviridae. FFkaV was found in field-grown figs from six Mediterranean countries with an incidence ranging from 15% to 25%. Copyright © 2011 Elsevier B.V. All rights reserved.

Using Förster-Resonance Energy Transfer to Measure Protein Interactions Between Bcl-2 Family Proteins on Mitochondrial Membranes.

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Pogmore, Justin P; Pemberton, James M; Chi, Xiaoke; Andrews, David W

2016-01-01

The Bcl-2 family of proteins regulates the process of mitochondrial outer membrane permeabilization, causing the release of cytochrome c and committing a cell to apoptosis. The majority of the functional interactions between these proteins occur at, on, or within the mitochondrial outer membrane, complicating structural studies of the proteins and complexes. As a result most in vitro studies of these protein-protein interactions use truncated proteins and/or detergents which can cause artificial interactions. Herein, we describe a detergent-free, fluorescence-based, in vitro technique to study binding between full-length recombinant Bcl-2 family proteins, particularly cleaved BID (cBID) and BCL-XL, on the membranes of purified mitochondria.

Protein resistance of surfaces modified with oligo(ethylene glycol) aryl diazonium derivatives.

Science.gov (United States)

Fairman, Callie; Ginges, Joshua Z; Lowe, Stuart B; Gooding, J Justin

2013-07-22

Anti-fouling surfaces are of great importance for reducing background interference in biosensor signals. Oligo(ethylene glycol) (OEG) moieties are commonly used to confer protein resistance on gold, silicon and carbon surfaces. Herein, we report the modification of surfaces using electrochemical deposition of OEG aryl diazonium salts. Using electrochemical and contact angle measurements, the ligand packing density is found to be loose, which supports the findings of the fluorescent protein labelling that aryl diazonium OEGs confer resistance to nonspecific adsorption of proteins albeit lower than alkane thiol-terminated OEGs. In addition to protein resistance, aryl diazonium attachment chemistry results in stable modification. In common with OEG species on gold electrodes, OEGs with distal hydroxyl moieties do confer superior protein resistance to those with a distal methoxy group. This is especially the case for longer derivatives where superior coiling of the OEG chains is possible. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Effect of protein/essential amino acids and resistance training on skeletal muscle hypertrophy: A case for whey protein

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Stout Jeffrey R

2010-06-01

Full Text Available Abstract Regardless of age or gender, resistance training or provision of adequate amounts of dietary protein (PRO or essential amino acids (EAA can increase muscle protein synthesis (MPS in healthy adults. Combined PRO or EAA ingestion proximal to resistance training, however, can augment the post-exercise MPS response and has been shown to elicit a greater anabolic effect than exercise plus carbohydrate. Unfortunately, chronic/adaptive response data comparing the effects of different protein sources is limited. A growing body of evidence does, however, suggest that dairy PRO, and whey in particular may: 1 stimulate the greatest rise in MPS, 2 result in greater muscle cross-sectional area when combined with chronic resistance training, and 3 at least in younger individuals, enhance exercise recovery. Therefore, this review will focus on whey protein supplementation and its effects on skeletal muscle mass when combined with heavy resistance training.

INTEGRATING GENETIC AND STRUCTURAL DATA ON HUMAN PROTEIN KINOME IN NETWORK-BASED MODELING OF KINASE SENSITIVITIES AND RESISTANCE TO TARGETED AND PERSONALIZED ANTICANCER DRUGS.

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Verkhivker, Gennady M

2016-01-01

The human protein kinome presents one of the largest protein families that orchestrate functional processes in complex cellular networks, and when perturbed, can cause various cancers. The abundance and diversity of genetic, structural, and biochemical data underlies the complexity of mechanisms by which targeted and personalized drugs can combat mutational profiles in protein kinases. Coupled with the evolution of system biology approaches, genomic and proteomic technologies are rapidly identifying and charactering novel resistance mechanisms with the goal to inform rationale design of personalized kinase drugs. Integration of experimental and computational approaches can help to bring these data into a unified conceptual framework and develop robust models for predicting the clinical drug resistance. In the current study, we employ a battery of synergistic computational approaches that integrate genetic, evolutionary, biochemical, and structural data to characterize the effect of cancer mutations in protein kinases. We provide a detailed structural classification and analysis of genetic signatures associated with oncogenic mutations. By integrating genetic and structural data, we employ network modeling to dissect mechanisms of kinase drug sensitivities to oncogenic EGFR mutations. Using biophysical simulations and analysis of protein structure networks, we show that conformational-specific drug binding of Lapatinib may elicit resistant mutations in the EGFR kinase that are linked with the ligand-mediated changes in the residue interaction networks and global network properties of key residues that are responsible for structural stability of specific functional states. A strong network dependency on high centrality residues in the conformation-specific Lapatinib-EGFR complex may explain vulnerability of drug binding to a broad spectrum of mutations and the emergence of drug resistance. Our study offers a systems-based perspective on drug design by unravelling

Structural basis of protein oxidation resistance: a lysozyme study.

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Marion Girod

Full Text Available Accumulation of oxidative damage in proteins correlates with aging since it can cause irreversible and progressive degeneration of almost all cellular functions. Apparently, native protein structures have evolved intrinsic resistance to oxidation since perfectly folded proteins are, by large most robust. Here we explore the structural basis of protein resistance to radiation-induced oxidation using chicken egg white lysozyme in the native and misfolded form. We study the differential resistance to oxidative damage of six different parts of native and misfolded lysozyme by a targeted tandem/mass spectrometry approach of its tryptic fragments. The decay of the amount of each lysozyme fragment with increasing radiation dose is found to be a two steps process, characterized by a double exponential evolution of their amounts: the first one can be largely attributed to oxidation of specific amino acids, while the second one corresponds to further degradation of the protein. By correlating these results to the structural parameters computed from molecular dynamics (MD simulations, we find the protein parts with increased root-mean-square deviation (RMSD to be more susceptible to modifications. In addition, involvement of amino acid side-chains in hydrogen bonds has a protective effect against oxidation Increased exposure to solvent of individual amino acid side chains correlates with high susceptibility to oxidative and other modifications like side chain fragmentation. Generally, while none of the structural parameters alone can account for the fate of peptides during radiation, together they provide an insight into the relationship between protein structure and susceptibility to oxidation.

Elicitin-induced distal systemic resistance in plants is mediated through the protein-protein interactions influenced by selected lysine residues

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Hana eUhlíková

2016-02-01

Full Text Available Elicitins are a family of small proteins with sterol-binding activity that are secreted by Phytophthora and Pythium spp. classified as oomycete PAMPs. Although alfa- and beta-elicitins bind with the same affinity to one high affinity binding site on the plasma membrane, beta-elicitins (possessing 6-7 lysine residues are generally 50- to 100-fold more active at inducing distal HR and systemic resistance than the alfa-isoforms (with only 1-3 lysine residues.To examine the role of lysine residues in elicitin biological activity, we employed site-directed mutagenesis to prepare a series of beta-elicitin cryptogein variants with mutations on specific lysine residues. In contrast to direct infiltration of protein into leaves, application to the stem revealed a rough correlation between protein’s charge and biological activity, resulting in protection against Phytophthora parasitica. A detailed analysis of proteins’ movement in plants showed no substantial differences in distribution through phloem indicating differences in consequent apoplastic or symplastic transport. In this process, an important role of homodimer formation together with the ability to form a heterodimer with potential partner represented by endogenous plants LTPs is suggested. Our work demonstrates a key role of selected lysine residues in these interactions and stresses the importance of processes preceding elicitin recognition responsible for induction of distal systemic resistance.

Identification and characterization of cytosolic Hansenula polymorpha proteins belonging to the Hsp70 protein family

NARCIS (Netherlands)

Titorenko, Vladimir I.; Evers, Melchior E.; Diesel, Andre; Samyn, Bart; Beeumen, Josef van; Roggenkamp, Rainer; Kiel, Jan A.K.W.; Klei, Ida J. van der; Veenhuis, Marten

We have isolated two members of the Hsp70 protein family from the yeast Hansenula polymorpha using affinity chromatography. Both proteins were located in the cytoplasm. One of these, designated Hsp72, was inducible in nature (e.g. by heat shock). The second protein (designated Hsc74) was

Targeting protein kinases to reverse multidrug resistance in sarcoma.

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Chen, Hua; Shen, Jacson; Choy, Edwin; Hornicek, Francis J; Duan, Zhenfeng

2016-02-01

Sarcomas are a group of cancers that arise from transformed cells of mesenchymal origin. They can be classified into over 50 subtypes, accounting for approximately 1% of adult and 15% of pediatric cancers. Wide surgical resection, radiotherapy, and chemotherapy are the most common treatments for the majority of sarcomas. Among these therapies, chemotherapy can palliate symptoms and prolong life for some sarcoma patients. However, sarcoma cells can have intrinsic or acquired resistance after treatment with chemotherapeutics drugs, leading to the development of multidrug resistance (MDR). MDR attenuates the efficacy of anticancer drugs and results in treatment failure for sarcomas. Therefore, overcoming MDR is an unmet need for sarcoma therapy. Certain protein kinases demonstrate aberrant expression and/or activity in sarcoma cells, which have been found to be involved in the regulation of sarcoma cell progression, such as cell cycle, apoptosis, and survival. Inhibiting these protein kinases may not only decrease the proliferation and growth of sarcoma cells, but also reverse their resistance to chemotherapeutic drugs to subsequently reduce the doses of anticancer drugs and decrease drug side-effects. The discovery of novel strategies targeting protein kinases opens a door to a new area of sarcoma research and provides insight into the mechanisms of MDR in chemotherapy. This review will focus on the recent studies in targeting protein kinase to reverse chemotherapeutic drug resistance in sarcoma. Copyright © 2015 Elsevier Ltd. All rights reserved.

The Ablation of Mitochondrial Protein Phosphatase Pgam5 Confers Resistance Against Metabolic Stress.

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Sekine, Shiori; Yao, Akari; Hattori, Kazuki; Sugawara, Sho; Naguro, Isao; Koike, Masato; Uchiyama, Yasuo; Takeda, Kohsuke; Ichijo, Hidenori

2016-03-01

Phosphoglycerate mutase family member 5 (PGAM5) is a mitochondrial protein phosphatase that has been reported to be involved in various stress responses from mitochondrial quality control to cell death. However, its roles in vivo are largely unknown. Here, we show that Pgam5-deficient mice are resistant to several metabolic insults. Under cold stress combined with fasting, Pgam5-deficient mice better maintained body temperature than wild-type mice and showed an extended survival rate. Serum triglycerides and lipid content in brown adipose tissue (BAT), a center of adaptive thermogenesis, were severely reduced in Pgam5-deficient mice. Moreover, although Pgam5 deficiency failed to maintain proper mitochondrial integrity in BAT, it reciprocally resulted in the dramatic induction of fibroblast growth factor 21 (FGF21) that activates various functions of BAT including thermogenesis. Thus, the enhancement of lipid metabolism and FGF21 may contribute to the cold resistance of Pgam5-deficient mice under fasting condition. Finally, we also found that Pgam5-deficient mice are resistant to high-fat-diet-induced obesity. Our study uncovered that PGAM5 is involved in the whole-body metabolism in response to stresses that impose metabolic challenges on mitochondria.

A novel mode of regulation of the Staphylococcus aureus Vancomycin-resistance-associated response regulator VraR mediated by Stk1 protein phosphorylation.

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Canova, Marc J; Baronian, Grégory; Brelle, Solène; Cohen-Gonsaud, Martin; Bischoff, Markus; Molle, Virginie

2014-04-25

The Staphylococcus aureus Vancomycin-resistance-associated response regulator VraR is known as an important response regulator, member of the VraTSR three-component signal transduction system that modulates the expression of the cell wall stress stimulon in response to a number of different cell wall active antibiotics. Given its crucial role in regulating gene expression in response to antibiotic challenges, VraR must be tightly regulated. We report here for the first time in S. aureus convergence of two major signal transduction systems, serine/threonine protein kinase and two (three)-component systems. We demonstrate that VraR can be phosphorylated by the staphylococcal Ser/Thr protein kinase Stk1 and that phosphorylation negatively affects its DNA-binding properties. Mass spectrometric analyses and site-directed mutagenesis identified Thr106, Thr119, Thr175 and Thr178 as phosphoacceptors. A S. aureus ΔvraR mutant expressing a VraR derivative that mimics constitutive phosphorylation, VraR_Asp, still exhibited markedly decreased antibiotic resistance against different cell wall active antibiotics, when compared to the wild-type, suggesting that VraR phosphorylation may represent a novel and presumably more general mechanism of regulation of the two (three)-component systems in staphylococci. Copyright © 2014 Elsevier Inc. All rights reserved.

Sifting through genomes with iterative-sequence clustering produces a large, phylogenetically diverse protein-family resource

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Sharpton Thomas J

2012-10-01

Full Text Available Abstract Background New computational resources are needed to manage the increasing volume of biological data from genome sequencing projects. One fundamental challenge is the ability to maintain a complete and current catalog of protein diversity. We developed a new approach for the identification of protein families that focuses on the rapid discovery of homologous protein sequences. Results We implemented fully automated and high-throughput procedures to de novo cluster proteins into families based upon global alignment similarity. Our approach employs an iterative clustering strategy in which homologs of known families are sifted out of the search for new families. The resulting reduction in computational complexity enables us to rapidly identify novel protein families found in new genomes and to perform efficient, automated updates that keep pace with genome sequencing. We refer to protein families identified through this approach as “Sifting Families,” or SFams. Our analysis of ~10.5 million protein sequences from 2,928 genomes identified 436,360 SFams, many of which are not represented in other protein family databases. We validated the quality of SFam clustering through statistical as well as network topology–based analyses. Conclusions We describe the rapid identification of SFams and demonstrate how they can be used to annotate genomes and metagenomes. The SFam database catalogs protein-family quality metrics, multiple sequence alignments, hidden Markov models, and phylogenetic trees. Our source code and database are publicly available and will be subject to frequent updates (http://edhar.genomecenter.ucdavis.edu/sifting_families/.

Expression and activity of multidrug resistance protein 1 in a murine thymoma cell line

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Echevarria-Lima, Juliana; Kyle-Cezar, Fernanda; Leite, Daniela F P; Capella, Luiz; Capella, Márcia A M; Rumjanek, Vivian M

2005-01-01

Multidrug resistance proteins [MRPs and P-glycoprotein (Pgp)] are members of the family of ATP-binding cassette (ABC) transport proteins, originally described as being involved in the resistance against anti-cancer agents in tumour cells. These proteins act as ATP-dependent efflux pumps and have now been described in normal cells where they exert physiological roles. The aim of this work was to investigate the expression and activity of MRP and Pgp in the thymoma cell line, EL4. It was observed that EL4 cells expressed mRNA for MRP1, but not for MRP2, MRP3 or Pgp. The activity of ABC transport proteins was evaluated by using the efflux of the fluorescent probes carboxy-2′-7′-dichlorofluorescein diacetate (CFDA) and rhodamine 123 (Rho 123). EL4 cells did not retain CFDA intracellularly, and MRP inhibitors (probenecid, indomethacin and MK 571) decreased MRP1 activity in a concentration-dependent manner. As expected, EL4 cells accumulated Rho 123, and the presence of cyclosporin A and verapamil did not modify this accumulation. Most importantly, when EL4 cells were incubated in the presence of the MRP1 inhibitors indomethacin and MK 571 for 6 days, they started to express CD4 and CD8 molecules on their surface, producing double-positive cells and CD8 single-positive cells. Our results suggest that MRP activity is important for the maintenance of the undifferentiated state in this cell type. This finding might have implications in the physiological process of normal thymocyte maturation. PMID:15804283

Developmental expression of Drosophila Wiskott-Aldrich Syndrome family proteins

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Rodriguez-Mesa, Evelyn; Abreu-Blanco, Maria Teresa; Rosales-Nieves, Alicia E.; Parkhurst, Susan M.

2012-01-01

Background Wiskott-Aldrich Syndrome (WASP) family proteins participate in many cellular processes involving rearrangements of the actin cytoskeleton. To the date, four WASP subfamily members have been described in Drosophila: Wash, WASp, SCAR, and Whamy. Wash, WASp, and SCAR are essential during early Drosophila development where they function in orchestrating cytoplasmic events including membrane-cytoskeleton interactions. A mutant for Whamy has not yet been reported. Results We generated monoclonal antibodies that are specific to Drosophila Wash, WASp, SCAR, and Whamy, and use these to describe their spatial and temporal localization patterns. Consistent with the importance of WASP family proteins in flies, we find that Wash, WASp, SCAR, and Whamy are dynamically expressed throughout oogenesis and embryogenesis. For example, we find that Wash accumulates at the oocyte cortex. WASp is highly expressed in the PNS, while SCAR is the most abundantly expressed in the CNS. Whamy exhibits an asymmetric subcellular localization that overlaps with mitochondria and is highly expressed in muscle. Conclusion All four WASP family members show specific expression patterns, some of which reflect their previously known roles and others revealing new potential functions. The monoclonal antibodies developed offer valuable new tools to investigate how WASP family proteins regulate actin cytoskeleton dynamics. PMID:22275148

Expression of the breast cancer resistance protein in breast cancer

NARCIS (Netherlands)

Faneyte, Ian F.; Kristel, Petra M. P.; Maliepaard, Marc; Scheffer, George L.; Scheper, Rik J.; Schellens, Jan H. M.; van de Vijver, Marc J.

2002-01-01

PURPOSE: The breast cancer resistance protein (BCRP) is involved in in vitro multidrug resistance and was first identified in the breast cancer cell line MCF7/AdrVp. The aim of this study was to investigate the role of BCRP in resistance of breast cancer to anthracycline treatment. EXPERIMENTAL

A study on hypophosphatemic vitamin D resistant rickets in a family

Energy Technology Data Exchange (ETDEWEB)

Chung, Doo Young; Byon, Joo Nam; Suh, Chee Jang; Won, Jong Jin [Won Kwang University School of Medicine, Seoul (Korea, Republic of)

1984-09-15

Hypophosphatemic vitamin D resistant rickets is a form of rickets characterized by typical structural deformities and roentgenographic and metabolic changes. It has a strong familiar tendency and appear to genetically transmitted. Authors experienced 7 patients with hypophoshatemic vitamin D resistant rickets which have been manifested through three generation in a family at Won Kwang University Hospital from December 1982 to May 1984. Authors studied hypophoshatemic vitamin D resistant rickets clinically, radiologically, biochemically and pathologically, and reported with review of literatures.

Influence of multidrug resistance and drug transport proteins on chemotherapy drug metabolism.

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Joyce, Helena; McCann, Andrew; Clynes, Martin; Larkin, Annemarie

2015-05-01

Chemotherapy involving the use of anticancer drugs remains an important strategy in the overall management of patients with metastatic cancer. Acquisition of multidrug resistance remains a major impediment to successful chemotherapy. Drug transporters in cell membranes and intracellular drug metabolizing enzymes contribute to the resistance phenotype and determine the pharmacokinetics of anticancer drugs in the body. ATP-binding cassette (ABC) transporters mediate the transport of endogenous metabolites and xenobiotics including cytotoxic drugs out of cells. Solute carrier (SLC) transporters mediate the influx of cytotoxic drugs into cells. This review focuses on the substrate interaction of these transporters, on their biology and what role they play together with drug metabolizing enzymes in eliminating therapeutic drugs from cells. The majority of anticancer drugs are substrates for the ABC transporter and SLC transporter families. Together, these proteins have the ability to control the influx and the efflux of structurally unrelated chemotherapeutic drugs, thereby modulating the intracellular drug concentration. These interactions have important clinical implications for chemotherapy because ultimately they determine therapeutic efficacy, disease progression/relapse and the success or failure of patient treatment.

A plant small polypeptide is a novel component of DNA-binding protein phosphatase 1-mediated resistance to plum pox virus in Arabidopsis.

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Castelló, María José; Carrasco, Jose Luis; Navarrete-Gómez, Marisa; Daniel, Jacques; Granot, David; Vera, Pablo

2011-12-01

DNA-binding protein phosphatases (DBPs) have been identified as a novel class of plant-specific regulatory factors playing a role in plant-virus interactions. NtDBP1 from tobacco (Nicotiana tabacum) was shown to participate in transcriptional regulation of gene expression in response to virus infection in compatible interactions, and AtDBP1, its closest relative in the model plant Arabidopsis (Arabidopsis thaliana), has recently been found to mediate susceptibility to potyvirus, one of the most speciose taxa of plant viruses. Here, we report on the identification of a novel family of highly conserved small polypeptides that interact with DBP1 proteins both in tobacco and Arabidopsis, which we have designated DBP-interacting protein 2 (DIP2). The interaction of AtDIP2 with AtDBP1 was demonstrated in vivo by bimolecular fluorescence complementation, and AtDIP2 was shown to functionally interfere with AtDBP1 in yeast. Furthermore, reducing AtDIP2 gene expression leads to increased susceptibility to the potyvirus Plum pox virus and to a lesser extent also to Turnip mosaic virus, whereas overexpression results in enhanced resistance. Therefore, we describe a novel family of conserved small polypeptides in plants and identify AtDIP2 as a novel host factor contributing to resistance to potyvirus in Arabidopsis.

Heterologously expressed bacterial and human multidrug resistance proteins confer cadmium resistance to Escherichia coli

NARCIS (Netherlands)

Achard-Joris, M; van Saparoea, HBV; Driessen, AJM; Bourdineaud, JP; Bourdineaud, Jean-Paul

2005-01-01

The human MDR1 gene is induced by cadmium exposure although no resistance to this metal is observed in human cells overexpressing hMDR1. To access the role of MDR proteins in cadmium resistance, human MDR1, Lactococcus lactis lmrA, and Oenococcus oeni omrA were expressed in an Escherichia coli tolC

Use of peptide antibodies to probe for the mitoxantrone resistance-associated protein MXR/BCRP/ABCP/ABCG2

DEFF Research Database (Denmark)

Litman, Thomas; Jensen, Ulla; Hansen, Alastair

2002-01-01

Recent studies have characterized the ABC half-transporter associated with mitoxantrone resistance in human cancer cell lines. Encoded by the ABCG2 gene, overexpression confers resistance to camptothecins, as well as to mitoxantrone. We developed four polyclonal antibodies against peptides corres...

Lack of association between the fatty acid binding protein 2 (FABP2) polymorphism with obesity and insulin resistance in two aboriginal populations from Chile.

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Pérez-Bravo, F; Fuentes, M; Angel, B; Sanchez, H; Carrasco, E; Santos, J L; Lera, L; Albala, C

2006-12-01

The aim of this study was to assess the frequency of fatty acid binding protein 2 (FABP2) Ala54Thr genetic polymorphism and to evaluate its association with obesity and insulin resistance in Chilean aboriginal populations. A sample of 96 urban Aymara and 111 urban Mapuche subjects aged 20-80 years were recruited for this cross-sectional study. Glucose, insulin and lipid profile were measured in fasting plasma samples. Insulin resistance was estimated through the HOMA-IR model. FABP2 Ala54Thr genotypes were determined by PCR followed by RFLP analysis. The allele frequency of Thr54 variant was estimated as 18.2% in Aymara subjects, which is one of the lowest reported to date. The corresponding frequency in Mapuche subjects was 31.9% (pMapuche group: OR=2.37, 95% CI 1.319-4.277, p=0.004) It is unlikely that Ala54Thr polymorphism of the FABP2 gene plays a relevant role in obesity and insulin resistance in Chilean ethnic groups.

An ochre mutation in the vitamin D receptor gene causes hereditary 1,25-dihydroxyvitamin D3-resistant rickets in three families

International Nuclear Information System (INIS)

Ritchie, H.H.; Hughes, M.R.; Thompson, E.T.; Pike, J.W.; O'Malley, B.W.; Malloy, P.J.; Feldman, D.; Hochberg, Z.

1989-01-01

Hereditary 1,25-dihydroxyvitamin D 3 -resistant rickets is a rare autosomal-recessive disease resulting from target-organ resistance to the action of the active hormonal form of vitamin D. Four affected children from three related families with the classical syndrome of hereditary 1,25-dihydroxyvitamin D 3 -resistant rickets and the absence of detectable binding to the vitamin D receptor (VDR) in cultured fibroblasts or lymphoblasts were examined for genetic abnormalities in the VDR gene. Genomic DNA from Epstein-Barr virus-transformed lymphoblasts of eight family members was isolated and amplified by polymerase chain reaction techniques. Amplified fragments containing the eight structural exons encoding the VDR protein were sequenced. The DNA from all affected children exhibited a single C → A base substitution within exon 7 at nucleotide 970. Although the affected children were all homozygotic for the mutation, the four parents tested all exhibited both wild-type and mutant alleles, indicating a heterozygous state. Recreated mutant receptor exhibited no specific 1,25-[ 3 H]dihydroxyvitamin D 3 binding and failed to activate a cotransfected VDR promoter-reporter gene construct. Thus these findings identify an ochre mutation in a human steroid hormone receptor in patients with hereditary 1,25-dihydroxyvitamin D 3 -resistant rickets

Dissection of Resistance Genes to Pseudomonas syringae pv. phaseolicola in UI3 Common Bean Cultivar.

Science.gov (United States)

González, Ana M; Godoy, Luís; Santalla, Marta

2017-11-23

Few quantitative trait loci have been mapped for resistance to Pseudomonas syringae pv. phaseolicola in common bean. Two F₂ populations were developed from the host differential UI3 cultivar. The objective of this study was to further characterize the resistance to races 1, 5, 7 and 9 of Psp included in UI3. Using a QTL mapping approach, 16 and 11 main-effect QTLs for pod and primary leaf resistance were located on LG10, explaining up to 90% and 26% of the phenotypic variation, respectively. The homologous genomic region corresponding to primary leaf resistance QTLs detected tested positive for the presence of resistance-associated gene cluster encoding nucleotide-binding and leucine-rich repeat (NL), Natural Resistance Associated Macrophage (NRAMP) and Pentatricopeptide Repeat family (PPR) proteins. It is worth noting that the main effect QTLs for resistance in pod were located inside a 3.5 Mb genomic region that included the Phvul.010G021200 gene, which encodes a protein that has the highest sequence similarity to the RIN4 gene of Arabidopsis, and can be considered an important candidate gene for the organ-specific QTLs identified here. These results support that resistance to Psp from UI3 might result from the immune response activated by combinations of R proteins, and suggest the guard model as an important mechanism in pod resistance to halo blight. The candidate genes identified here warrant functional studies that will help in characterizing the actual defense gene(s) in UI3 genotype.

A Review on Structures and Functions of Bcl-2 Family Proteins from Homo sapiens.

Science.gov (United States)

Sivakumar, Dakshinamurthy; Sivaraman, Thirunavukkarasu

2016-01-01

Cancer cells evade apoptosis, which is regulated by proteins of Bcl-2 family in the intrinsic pathways. Numerous experimental three-dimensional (3D) structures of the apoptotic proteins and the proteins bound with small chemical molecules/peptides/proteins have been reported in the literature. In this review article, the 3D structures of the Bcl-2 family proteins from Homo sapiens and as well complex structures of the anti-apoptotic proteins bound with small molecular inhibitors reported in the literature to date have been comprehensively listed out and described in detail. Moreover, the molecular mechanisms by which the Bcl-2 family proteins modulate the apoptotic processes and strategies for designing antagonists to anti-apoptotic proteins have been concisely discussed.

Characterization and drug resistance patterns of Ewing's sarcoma family tumor cell lines.

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William A May

Full Text Available Despite intensive treatment with chemotherapy, radiotherapy and surgery, over 70% of patients with metastatic Ewing's Sarcoma Family of Tumors (EFT will die of their disease. We hypothesize that properly characterized laboratory models reflecting the drug resistance of clinical tumors will facilitate the application of new therapeutic agents to EFT. To determine resistance patterns, we studied newly established EFT cell lines derived from different points in therapy: two established at diagnosis (CHLA-9, CHLA-32, two after chemotherapy and progressive disease (CHLA-10, CHLA-25, and two at relapse after myeloablative therapy and autologous bone marrow transplantation (post-ABMT (CHLA-258, COG-E-352. The new lines were compared to widely studied EFT lines TC-71, TC-32, SK-N-MC, and A-673. These lines were extensively characterized with regard to identity (short tandem repeat (STR analysis, p53, p16/14 status, and EWS/ETS breakpoint and target gene expression profile. The DIMSCAN cytotoxicity assay was used to assess in vitro drug sensitivity to standard chemotherapy agents. No association was found between drug resistance and the expression of EWS/ETS regulated genes in the EFT cell lines. No consistent association was observed between drug sensitivity and p53 functionality or between drug sensitivity and p16/14 functionality across the cell lines. Exposure to chemotherapy prior to cell line initiation correlated with drug resistance of EFT cell lines in 5/8 tested agents at clinically achievable concentrations (CAC or the lower tested concentration (LTC: (cyclophosphamide (as 4-HC and doxorubicin at CAC, etoposide, irinotecan (as SN-38 and melphalan at LTC; P<0.1 for one agent, and P<0.05 for four agents. This panel of well-characterized drug-sensitive and drug-resistant cell lines will facilitate in vitro preclinical testing of new agents for EFT.

Asteroid Family Associations of Main-Belt Comets

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Hsieh, Henry H.; Novakovic, Bojan; Kim, Yoonyoung; Brasser, Ramon

2016-10-01

We present a population-level analysis of the asteroid family associations of known main-belt comets or main-belt comet candidates (which, to date, have largely just been analyzed on individual bases as they have been discovered). In addition to family associations that have already been reported in the literature, we have identified dynamical relationships between 324P/La Sagra and the Alauda family, P/2015 X6 (PANSTARRS) and the Aeolia family, and P/2016 G1 (PANSTARRS) and the Adeona family. We will discuss the overall implications of these family associations, particularly as they pertain to the hypothesis that members of primitive asteroid family members may be more susceptible to producing observable sublimation-driven dust emission activity, and thus becoming main-belt comets. We will also discuss the significance of other dynamical and physical properties of a family or sub-family as they relate to the likelihood of that family containing one or more currently active main-belt comets.

Associations between depressive symptoms and insulin resistance

DEFF Research Database (Denmark)

Adriaanse, M C; Dekker, J M; Nijpels, G

2006-01-01

AIMS/HYPOTHESIS: The association between depression and insulin resistance has been investigated in only a few studies, with contradictory results reported. The aim of this study was to determine whether the association between symptoms of depression and insulin resistance varies across glucose...... established type 2 diabetes mellitus. Main outcome measures were insulin resistance defined by the homeostasis model assessment for insulin resistance (HOMA-IR) and symptoms of depression using the Centre for Epidemiologic Studies Depression Scale (CES-D). RESULTS: In the total sample, we found a weak.......942). The association between depressive symptoms and insulin resistance was similar for men and women. CONCLUSIONS/INTERPRETATION: We found only weak associations between depressive symptoms and insulin resistance, which did not differ among different glucose metabolism subgroups or between men and women....

Parental employment and work-family stress: Associations with family food environments

Science.gov (United States)

Bauer, Katherine W.; Hearst, Mary O.; Escoto, Kamisha; Berge, Jerica M.; Neumark-Sztainer, Dianne

2013-01-01

Parental employment provides many benefits to children's health. However, an increasing number of studies have observed associations between mothers' full-time employment and less healthful family food environments. Few studies have examined other ways in which parental employment may be associated with the family food environment, including the role of fathers' employment and parents' stress balancing work and home obligations. This study utilized data from Project F-EAT, a population-based study of a socio-demographically diverse sample of 3709 parents of adolescents living in a metropolitan area in the Midwestern United States, to examine cross-sectional associations between mothers' and fathers' employment status and parents' work-life stress with multiple aspects of the family food environment. Among parents participating in Project F-EAT, 64% of fathers and 46% of mothers were full-time employed, while 25% of fathers and 37% of mothers were not employed. Results showed that full-time employed mothers reported fewer family meals, less frequent encouragement of their adolescents' healthful eating, lower fruit and vegetable intake, and less time spent on food preparation, compared to part-time and not-employed mothers, after adjusting for socio-demographics. Full-time employed fathers reported significantly fewer hours of food preparation; no other associations were seen between fathers' employment status and characteristics of the family food environment. In contrast, higher work-life stress among both parents was associated with less healthful family food environment characteristics including less frequent family meals and more frequent sugar-sweetened beverage and fast food consumption by parents. Among dual-parent families, taking into account the employment characteristics of the other parent did not substantially alter the relationships between work-life stress and family food environment characteristics. While parental employment is beneficial for many

Parental employment and work-family stress: associations with family food environments.

Science.gov (United States)

Bauer, Katherine W; Hearst, Mary O; Escoto, Kamisha; Berge, Jerica M; Neumark-Sztainer, Dianne

2012-08-01

Parental employment provides many benefits to children's health. However, an increasing number of studies have observed associations between mothers' full-time employment and less healthful family food environments. Few studies have examined other ways in which parental employment may be associated with the family food environment, including the role of fathers' employment and parents' stress balancing work and home obligations. This study utilized data from Project F-EAT, a population-based study of a socio-demographically diverse sample of 3709 parents of adolescents living in a metropolitan area in the Midwestern United States, to examine cross-sectional associations between mothers' and fathers' employment status and parents' work-life stress with multiple aspects of the family food environment. Among parents participating in Project F-EAT, 64% of fathers and 46% of mothers were full-time employed, while 25% of fathers and 37% of mothers were not employed. Results showed that full-time employed mothers reported fewer family meals, less frequent encouragement of their adolescents' healthful eating, lower fruit and vegetable intake, and less time spent on food preparation, compared to part-time and not-employed mothers, after adjusting for socio-demographics. Full-time employed fathers reported significantly fewer hours of food preparation; no other associations were seen between fathers' employment status and characteristics of the family food environment. In contrast, higher work-life stress among both parents was associated with less healthful family food environment characteristics including less frequent family meals and more frequent sugar-sweetened beverage and fast food consumption by parents. Among dual-parent families, taking into account the employment characteristics of the other parent did not substantially alter the relationships between work-life stress and family food environment characteristics. While parental employment is beneficial for many

Characterization of the Pichia pastoris protein-O-mannosyltransferase gene family.

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Juergen H Nett

Full Text Available The methylotrophic yeast, Pichiapastoris, is an important organism used for the production of therapeutic proteins. However, the presence of fungal-like glycans, either N-linked or O-linked, can elicit an immune response or enable the expressed protein to bind to mannose receptors, thus reducing their efficacy. Previously we have reported the elimination of β-linked glycans in this organism. In the current report we have focused on reducing the O-linked mannose content of proteins produced in P. pastoris, thereby reducing the potential to bind to mannose receptors. The initial step in the synthesis of O-linked glycans in P. pastoris is the transfer of mannose from dolichol-phosphomannose to a target protein in the yeast secretory pathway by members of the protein-O-mannosyltransferase (PMT family. In this report we identify and characterize the members of the P. pastoris PMT family. Like Candida albicans, P. pastoris has five PMT genes. Based on sequence homology, these PMTs can be grouped into three sub-families, with both PMT1 and PMT2 sub-families possessing two members each (PMT1 and PMT5, and PMT2 and PMT6, respectively. The remaining sub-family, PMT4, has only one member (PMT4. Through gene knockouts we show that PMT1 and PMT2 each play a significant role in O-glycosylation. Both, by gene knockouts and the use of Pmt inhibitors we were able to significantly reduce not only the degree of O-mannosylation, but also the chain-length of these glycans. Taken together, this reduction of O-glycosylation represents an important step forward in developing the P. pastoris platform as a suitable system for the production of therapeutic glycoproteins.

Effects of aging and insulin resistant states on protein anabolic responses in older adults.

Science.gov (United States)

Morais, Jose A; Jacob, Kathryn Wright; Chevalier, Stéphanie

2018-07-15

levels during an intravenous fed state supplying a generous amount of protein, in active healthy elderly women. Obese elderly women with and without type 2 diabetes have insulin resistance of protein anabolism at the whole-body level, but this resistance is worsened with diabetes when glucose metabolism is further impaired. More investigation is needed to determine the exact role of insulin in promoting anabolism with aging. The findings from our group are relevant for the field of sarcopenia research as they provide a rationale to offer low cost nutritional interventions for overcoming this detrimental condition associated with aging and diabetes. Copyright © 2018. Published by Elsevier Inc.

Low-dose oral contraceptives and acquired resistance to activated protein C: a randomised cross-over study

NARCIS (Netherlands)

Rosing, J.; Middeldorp, S.; Curvers, J.; Christella, M.; Thomassen, L. G.; Nicolaes, G. A.; Meijers, J. C.; Bouma, B. N.; Büller, H. R.; Prins, M. H.; Tans, G.

1999-01-01

BACKGROUND: We have reported previously that, compared with use of second-generation oral contraceptives, the use of third-generation oral contraceptives is associated with increased resistance to the anticoagulant action of activated protein C (APC). Owing to the cross-sectional design of that

Homologs of the Acinetobacter baumannii AceI transporter represent a new family of bacterial multidrug efflux systems.

Science.gov (United States)

Hassan, Karl A; Liu, Qi; Henderson, Peter J F; Paulsen, Ian T

2015-02-10

Multidrug efflux systems are a major cause of resistance to antimicrobials in bacteria, including those pathogenic to humans, animals, and plants. These proteins are ubiquitous in these pathogens, and five families of bacterial multidrug efflux systems have been identified to date. By using transcriptomic and biochemical analyses, we recently identified the novel AceI (Acinetobacter chlorhexidine efflux) protein from Acinetobacter baumannii that conferred resistance to the biocide chlorhexidine, via an active efflux mechanism. Proteins homologous to AceI are encoded in the genomes of many other bacterial species and are particularly prominent within proteobacterial lineages. In this study, we expressed 23 homologs of AceI and examined their resistance and/or transport profiles. MIC analyses demonstrated that, like AceI, many of the homologs conferred resistance to chlorhexidine. Many of the AceI homologs conferred resistance to additional biocides, including benzalkonium, dequalinium, proflavine, and acriflavine. We conducted fluorimetric transport assays using the AceI homolog from Vibrio parahaemolyticus and confirmed that resistance to both proflavine and acriflavine was mediated by an active efflux mechanism. These results show that this group of AceI homologs represent a new family of bacterial multidrug efflux pumps, which we have designated the proteobacterial antimicrobial compound efflux (PACE) family of transport proteins. Bacterial multidrug efflux pumps are an important class of resistance determinants that can be found in every bacterial genome sequenced to date. These transport proteins have important protective functions for the bacterial cell but are a significant problem in the clinical setting, since a single efflux system can mediate resistance to many structurally and mechanistically diverse antibiotics and biocides. In this study, we demonstrate that proteins related to the Acinetobacter baumannii AceI transporter are a new class of multidrug

RACK1 downregulates levels of the pro-apoptotic protein Fem1b in apoptosis-resistant colon cancer cells.

Science.gov (United States)

Subauste, M Cecilia; Ventura-Holman, Tereza; Du, Liqin; Subauste, Jose S; Chan, Shing-Leng; Yu, Victor C; Maher, Joseph F

2009-12-01

Evasion of apoptosis plays an important role in colon cancer progression. Following loss of the Apc tumor suppressor gene in mice, the gene encoding Fem1b is upregulated early in neoplastic intestinal epithelium. Fem1b is a pro-apoptotic protein that interacts with Fas, TNFR1 and Apaf-1, and increased expression of Fem1b induces apoptosis of cancer cells. Fem1b is a homolog of FEM-1, a protein in Caenorhabditis elegans that is negatively regulated by ubiquitination and proteasomal degradation. To study Fem1b regulation in colon cancer progression, we used apoptotis-sensitive SW480 cells, derived from a primary colon cancer, and their isogenic, apoptosis-resistant counterparts SW620 cells, derived from a subsequent metastatic lesion in the same patient. Treatment with proteasome inhibitor increased Fem1b protein levels in SW620 cells, but not in SW480 cells. In SW620 cells we found that endogenous Fem1b co-immunoprecipitates in complexes with RACK1, a protein known to mediate ubiquitination and proteasomal degradation of other pro-apoptotic proteins and to be upregulated in colon cancer. Full-length Fem1b, or the N-terminal region of Fem1b, associated with RACK1 when co-expressed in HEK293T cells, and RACK1 stimulated ubiquitination of Fem1b. RACK1 overexpression in SW620 cells led to downregulation of Fem1b protein levels. Conversely, downregulation of RACK1 led to upregulation of Fem1b protein levels, associated with induction of apoptosis, and this apoptosis was inhibited by blocking Fem1b protein upregulation. In conclusion, RACK1 downregulates levels of the pro-apoptotic protein Fem1b in metastatic, apoptosis-resistant colon cancer cells, which may promote apoptosis-resistance during progression of colon cancer.

Resistance Exercise Training-Induced Muscle Hypertrophy Was Associated with Reduction of Inflammatory Markers in Elderly Women

Directory of Open Access Journals (Sweden)

Kishiko Ogawa

2010-01-01

Full Text Available Aging is associated with low-grade inflammation. The benefits of regular exercise for the elderly are well established, whereas less is known about the impact of low-intensity resistance exercise on low-grade inflammation in the elderly. Twenty-one elderly women (mean age ± SD, 85.0 ± 4.5 years participated in 12 weeks of resistance exercise training. Muscle thickness and circulating levels of C-reactive protein (CRP, serum amyloid A (SAA, heat shock protein (HSP70, tumor necrosis factor (TNF-α, interleukin (IL-1, IL-6, monocyte chemotactic protein (MCP-1, insulin, insulin-like growth factor (IGF-I, and vascular endothelial growth factor (VEGF were measured before and after the exercise training. Training reduced the circulating levels of CRP, SAA (P<.05, HSP70, IGF-I, and insulin (P<.01. The training-induced reductions in CRP and TNF-α were significantly (P<.01, P<.05 associated with increased muscle thickness (r=−0.61, r=−0.54, respectively. None of the results were significant after applying a Bonferroni correction. Resistance training may assist in maintaining or improving muscle volume and reducing low-grade inflammation.

Plasma phospholipid transfer protein activity is related to insulin resistance : impaired acute lowering by insulin in obese Type II diabetic patients

NARCIS (Netherlands)

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

Cholesteryl ester transfer protein (CETP) and phospholipid transfer protein (PLTP) have important functions in high density lipoprotein (HDL) metabolism. We determined the association of plasma CETP and PLTP activities (measured with exogenous' substrate assays) with insulin resistance, plasma

Activation of mitochondrial promoter PH-binding protein in a radio-resistant Chinese hamster cell strain associated with Bcl-2

International Nuclear Information System (INIS)

Roychoudhury, Paromita; Ghosh, Utpal; Bhattacharyya, Nitai P.; Chaudhuri, Keya

2006-01-01

The cellular response to ionizing radiation is mediated by a complex interaction of number of proteins involving different pathways. Previously, we have shown that up regulation of mitochondrial genes ND1, ND4, and COX1 transcribed from the heavy strand promoter (P H ) has been increased in a radio-resistant cell strain designated as M5 in comparison with the parental Chinese hamster V79 cells. These genes are also up regulated in Chinese hamster V79 cells VB13 that express exogenous human Bcl2. In the present study, the expression of the gene ND6 that is expressed from the light strand promoter (P L ) was found to be similar in both the cell lines, as determined by RT-PCR. To test the possibility that this differential expression of mitochondrial genes under these two promoters was mediated by differences in proteins' affinity to interact with these promoters, we have carried out electrophoretic mobility shift assay (EMSA) using mitochondrial cell extracts from these two cell lines. Our result of these experiments revealed that two different proteins formed complex with the synthetic promoters and higher amount of protein from M5 cell extracts interacted with the P H promoter in comparison to that observed with cell extracts from Chinese hamster V79 cells. The promoter-specific differential binding of proteins was also observed in VB13. These results showed that differential mitochondrial gene expression observed earlier in the radio-resistant M5 cells was due to enhanced interaction proteins with the promoters P H and mediated by the expression of Bcl2

Overexpression of protein kinase A - RIalpha reduces lipofection efficiency of cisplatin-resistant human tumor cells.

Science.gov (United States)

Son, K K; Rosenblatt, J

2001-04-10

Cisplatin-resistant variant A2780CP/vector cells were 4.0-5.3-fold more transfectable and 7.6-fold more resistant to cisplatin than their parent cisplatin-sensitive human ovarian carcinoma A2780/vector cells. Overexpression of cAMP-dependent protein kinase Type I regulatory alpha subunit (PKA-RIalpha) gene in A2780CP cells significantly reduced (maximum 47.0%) the transfection activity, with a slight reduction (maximum 27.3%) of cisplatin resistance, of A2780CP cells. However, RIalpha-overexpressing A2780CP (A2780CP/RIalpha) cells were still 2.5-to 3.0-fold more transfectable and 5.5-fold more resistant to cisplatin than A2780 cells. This results suggest that gene transfer efficiency is associated with cisplatin resistance, in part, through the PKA-mediated cAMP signal transduction pathway.

Characterization of resistance gene analogues (RGAs) in apple (Malus × domestica Borkh.) and their evolutionary history of the Rosaceae family.

Science.gov (United States)

Perazzolli, Michele; Malacarne, Giulia; Baldo, Angela; Righetti, Laura; Bailey, Aubrey; Fontana, Paolo; Velasco, Riccardo; Malnoy, Mickael

2014-01-01

The family of resistance gene analogues (RGAs) with a nucleotide-binding site (NBS) domain accounts for the largest number of disease resistance genes and is one of the largest gene families in plants. We have identified 868 RGAs in the genome of the apple (Malus × domestica Borkh.) cultivar 'Golden Delicious'. This represents 1.51% of the total number of predicted genes for this cultivar. Several evolutionary features are pronounced in M. domestica, including a high fraction (80%) of RGAs occurring in clusters. This suggests frequent tandem duplication and ectopic translocation events. Of the identified RGAs, 56% are located preferentially on six chromosomes (Chr 2, 7, 8, 10, 11, and 15), and 25% are located on Chr 2. TIR-NBS and non-TIR-NBS classes of RGAs are primarily exclusive of different chromosomes, and 99% of non-TIR-NBS RGAs are located on Chr 11. A phylogenetic reconstruction was conducted to study the evolution of RGAs in the Rosaceae family. More than 1400 RGAs were identified in six species based on their NBS domain, and a neighbor-joining analysis was used to reconstruct the phylogenetic relationships among the protein sequences. Specific phylogenetic clades were found for RGAs of Malus, Fragaria, and Rosa, indicating genus-specific evolution of resistance genes. However, strikingly similar RGAs were shared in Malus, Pyrus, and Prunus, indicating high conservation of specific RGAs and suggesting a monophyletic origin of these three genera.

Characterization of resistance gene analogues (RGAs in apple (Malus × domestica Borkh. and their evolutionary history of the Rosaceae family.

Directory of Open Access Journals (Sweden)

Michele Perazzolli

Full Text Available The family of resistance gene analogues (RGAs with a nucleotide-binding site (NBS domain accounts for the largest number of disease resistance genes and is one of the largest gene families in plants. We have identified 868 RGAs in the genome of the apple (Malus × domestica Borkh. cultivar 'Golden Delicious'. This represents 1.51% of the total number of predicted genes for this cultivar. Several evolutionary features are pronounced in M. domestica, including a high fraction (80% of RGAs occurring in clusters. This suggests frequent tandem duplication and ectopic translocation events. Of the identified RGAs, 56% are located preferentially on six chromosomes (Chr 2, 7, 8, 10, 11, and 15, and 25% are located on Chr 2. TIR-NBS and non-TIR-NBS classes of RGAs are primarily exclusive of different chromosomes, and 99% of non-TIR-NBS RGAs are located on Chr 11. A phylogenetic reconstruction was conducted to study the evolution of RGAs in the Rosaceae family. More than 1400 RGAs were identified in six species based on their NBS domain, and a neighbor-joining analysis was used to reconstruct the phylogenetic relationships among the protein sequences. Specific phylogenetic clades were found for RGAs of Malus, Fragaria, and Rosa, indicating genus-specific evolution of resistance genes. However, strikingly similar RGAs were shared in Malus, Pyrus, and Prunus, indicating high conservation of specific RGAs and suggesting a monophyletic origin of these three genera.

Characterization of Resistance Gene Analogues (RGAs) in Apple (Malus × domestica Borkh.) and Their Evolutionary History of the Rosaceae Family

Science.gov (United States)

Baldo, Angela; Righetti, Laura; Bailey, Aubrey; Fontana, Paolo; Velasco, Riccardo; Malnoy, Mickael

2014-01-01

The family of resistance gene analogues (RGAs) with a nucleotide-binding site (NBS) domain accounts for the largest number of disease resistance genes and is one of the largest gene families in plants. We have identified 868 RGAs in the genome of the apple (Malus × domestica Borkh.) cultivar ‘Golden Delicious’. This represents 1.51% of the total number of predicted genes for this cultivar. Several evolutionary features are pronounced in M. domestica, including a high fraction (80%) of RGAs occurring in clusters. This suggests frequent tandem duplication and ectopic translocation events. Of the identified RGAs, 56% are located preferentially on six chromosomes (Chr 2, 7, 8, 10, 11, and 15), and 25% are located on Chr 2. TIR-NBS and non-TIR-NBS classes of RGAs are primarily exclusive of different chromosomes, and 99% of non-TIR-NBS RGAs are located on Chr 11. A phylogenetic reconstruction was conducted to study the evolution of RGAs in the Rosaceae family. More than 1400 RGAs were identified in six species based on their NBS domain, and a neighbor-joining analysis was used to reconstruct the phylogenetic relationships among the protein sequences. Specific phylogenetic clades were found for RGAs of Malus, Fragaria, and Rosa, indicating genus-specific evolution of resistance genes. However, strikingly similar RGAs were shared in Malus, Pyrus, and Prunus, indicating high conservation of specific RGAs and suggesting a monophyletic origin of these three genera. PMID:24505246

Familial hyperinsulinemia associated with secretion of an abnormal insulin, and coexistence of insulin resistance in the propositus.

Science.gov (United States)

Vinik, A I; Seino, S; Funakoshi, A; Schwartz, J; Matsumoto, M; Schteingart, D E; Fu, Z Z; Tsai, S T

1986-04-01

A 45-yr-old muscular nonobese white man who had a 9-yr history of syncopal episodes was studied on several occasions between April 1979 and August 1984. Fasting glucose concentrations ranged between 74-115 mg/dl, and those of insulin ranged between 14-64 microU/ml. Reactive hypoglycemia 3-4 h after ingestion of glucose occurred in the first 2 yr. Glucose tolerance was impaired in 1979, from February 1982 through September 1983, and again in August 1984. The maximum plasma insulin response to glucose ranged between 475-1630 microU/ml. When studied in November 1982, insulin (0.1 U/kg) caused a fall in blood glucose concentration of only 25% (normal, greater than 50%), and maximal glucose utilization during the euglycemic hyperinsulinemic clamp was 7.5 mg/kg . min (normal, greater than 12 mg/kg . min). Plasma counterregulatory hormone concentrations were normal, and antibodies to insulin and the insulin receptor were absent. Binding of exogenous insulin to the patient's cellular receptors (monocytes, red blood cells, and skin fibroblasts) was normal. Insulin was purified from plasma by immunoaffinity and molecular sieve chromatography and was found to elute later than human insulin on reversed phase high performance liquid chromatography. It was more hydrophobic than normal human insulin and had only 10% of the activity of normal insulin in terms of ability to bind to and stimulate glucose metabolism in isolated rat adipocytes. The abnormal insulin was identified in two of three sons and a sister, but not in the mother, brother, or niece. Sensitivity to insulin was normal in the two sons who had abnormal insulin. These results suggest that in this family the abnormal insulin was due to a biosynthetic defect, inherited as an autosomal dominant trait. The hyperinsulinemia was not associated with diabetes in family members who had no insulin resistance.

A combinatorial approach to detect coevolved amino acid networks in protein families of variable divergence.

Directory of Open Access Journals (Sweden)

Julie Baussand

2009-09-01

Full Text Available Communication between distant sites often defines the biological role of a protein: amino acid long-range interactions are as important in binding specificity, allosteric regulation and conformational change as residues directly contacting the substrate. The maintaining of functional and structural coupling of long-range interacting residues requires coevolution of these residues. Networks of interaction between coevolved residues can be reconstructed, and from the networks, one can possibly derive insights into functional mechanisms for the protein family. We propose a combinatorial method for mapping conserved networks of amino acid interactions in a protein which is based on the analysis of a set of aligned sequences, the associated distance tree and the combinatorics of its subtrees. The degree of coevolution of all pairs of coevolved residues is identified numerically, and networks are reconstructed with a dedicated clustering algorithm. The method drops the constraints on high sequence divergence limiting the range of applicability of the statistical approaches previously proposed. We apply the method to four protein families where we show an accurate detection of functional networks and the possibility to treat sets of protein sequences of variable divergence.

Associations between family characteristics and parental empowerment in the family, family service situations and the family service system.

Science.gov (United States)

Vuorenmaa, M; Perälä, M-L; Halme, N; Kaunonen, M; Åstedt-Kurki, P

2016-01-01

Parental empowerment signifies parents' sense of confidence in managing their children, interacting with services that their children use and improving child care services. High empowerment is associated with parents' resilience to demands and their confidence to make decisions and take actions that positively affect their families. Most families with children access various healthcare and education services. Professionals working in these services are therefore ideally placed to reinforce parental empowerment. However, little is known about the characteristics associated with parental empowerment within a generic sample of parents or in the context of basic child care services. The aim of this study was to assess how family characteristics are associated with maternal and paternal empowerment in the family, in service situations and in the service system. Parental empowerment was measured among 955 parents (mothers = 571; fathers = 384) of children aged 0-9 years using the Generic Family Empowerment Scale. Family characteristics were assessed through questions on children, parents and the life situation. Associations between empowerment and family characteristics were evaluated using one-way analysis of variance and t-test. Parental empowerment was predicted by multiple linear regression analysis. Parents' concerns related to their parenting, such as whether they possessed sufficient skills as a parent or losing their temper with children, as well as experiences of stress in everyday life, were negatively associated with all dimensions of maternal and paternal empowerment. Both determinants were more common and more significant in empowerment than child-related problems. Promoting parental self-confidence and providing appropriate emotional and concrete support for everyday functioning may reinforce parental empowerment, thereby enhancing families' well-being and coping, as well as improving their access to required services and timely support. Finally

Production of low-affinity penicillin-binding protein by low- and high-resistance groups of methicillin-resistant Staphylococcus aureus.

Science.gov (United States)

Murakami, K; Nomura, K; Doi, M; Yoshida, T

1987-01-01

Methicillin- and cephem-resistant Staphylococcus aureus (137 strains) for which the cefazolin MICs are at least 25 micrograms/ml could be classified into low-resistance (83% of strains) and high-resistance (the remaining 17%) groups by the MIC of flomoxef (6315-S), a 1-oxacephalosporin. The MICs were less than 6.3 micrograms/ml and more than 12.5 micrograms/ml in the low- and high-resistance groups, respectively. All strains produced penicillin-binding protein 2' (PBP 2'), which has been associated with methicillin resistance and which has very low affinity for beta-lactam antibiotics. Production of PBP 2' was regulated differently in low- and high-resistance strains. With penicillinase-producing strains of the low-resistance group, cefazolin, cefamandole, and cefmetazole induced PBP 2' production about 5-fold, while flomoxef induced production 2.4-fold or less. In contrast, penicillinase-negative variants of low-resistance strains produced PBP 2' constitutively in large amounts and induction did not occur. With high-resistance strains, flomoxef induced PBP 2' to an extent similar to that of cefazolin in both penicillinase-producing and -negative strains, except for one strain in which the induction did not occur. The amount of PBP 2' induced by beta-lactam antibiotics in penicillinase-producing strains of the low-resistance group correlated well with resistance to each antibiotic. Large amounts of PBP 2' in penicillinase-negative variants of the low-resistance group did not raise the MICs of beta-lactam compounds, although these strains were more resistant when challenged with flomoxef for 2 h. Different regulation of PBP 2' production was demonstrated in the high- and low-resistance groups, and factor(s) other than PBP 2' were suggested to be involved in the methicillin resistance of high-resistance strains. Images PMID:3499861

Molecular Simulations of Sequence-Specific Association of Transmembrane Proteins in Lipid Bilayers

Science.gov (United States)

Doxastakis, Manolis; Prakash, Anupam; Janosi, Lorant

2011-03-01

Association of membrane proteins is central in material and information flow across the cellular membranes. Amino-acid sequence and the membrane environment are two critical factors controlling association, however, quantitative knowledge on such contributions is limited. In this work, we study the dimerization of helices in lipid bilayers using extensive parallel Monte Carlo simulations with recently developed algorithms. The dimerization of Glycophorin A is examined employing a coarse-grain model that retains a level of amino-acid specificity, in three different phospholipid bilayers. Association is driven by a balance of protein-protein and lipid-induced interactions with the latter playing a major role at short separations. Following a different approach, the effect of amino-acid sequence is studied using the four transmembrane domains of the epidermal growth factor receptor family in identical lipid environments. Detailed characterization of dimer formation and estimates of the free energy of association reveal that these helices present significant affinity to self-associate with certain dimers forming non-specific interfaces.

A compendium of transcription factor and Transcriptionally active protein coding gene families in cowpea (Vigna unguiculata L.).

Science.gov (United States)

Misra, Vikram A; Wang, Yu; Timko, Michael P

2017-11-22

Cowpea (Vigna unguiculata (L.) Walp.) is the most important food and forage legume in the semi-arid tropics of sub-Saharan Africa where approximately 80% of worldwide production takes place primarily on low-input, subsistence farm sites. Among the major goals of cowpea breeding and improvement programs are the rapid manipulation of agronomic traits for seed size and quality and improved resistance to abiotic and biotic stresses to enhance productivity. Knowing the suite of transcription factors (TFs) and transcriptionally active proteins (TAPs) that control various critical plant cellular processes would contribute tremendously to these improvement aims. We used a computational approach that employed three different predictive pipelines to data mine the cowpea genome and identified over 4400 genes representing 136 different TF and TAP families. We compare the information content of cowpea to two evolutionarily close species common bean (Phaseolus vulgaris), and soybean (Glycine max) to gauge the relative informational content. Our data indicate that correcting for genome size cowpea has fewer TF and TAP genes than common bean (4408 / 5291) and soybean (4408/ 11,065). Members of the GROWTH-REGULATING FACTOR (GRF) and Auxin/indole-3-acetic acid (Aux/IAA) gene families appear to be over-represented in the genome relative to common bean and soybean, whereas members of the MADS (Minichromosome maintenance deficient 1 (MCM1), AGAMOUS, DEFICIENS, and serum response factor (SRF)) and C2C2-YABBY appear to be under-represented. Analysis of the AP2-EREBP APETALA2-Ethylene Responsive Element Binding Protein (AP2-EREBP), NAC (NAM (no apical meristem), ATAF1, 2 (Arabidopsis transcription activation factor), CUC (cup-shaped cotyledon)), and WRKY families, known to be important in defense signaling, revealed changes and phylogenetic rearrangements relative to common bean and soybean that suggest these groups may have evolved different functions. The availability of detailed

Differential association of the Na+/H+ Exchanger Regulatory Factor (NHERF) family of adaptor proteins with the raft- and the non-raft brush border membrane fractions of NHE3.

Science.gov (United States)

Sultan, Ayesha; Luo, Min; Yu, Qin; Riederer, Brigitte; Xia, Weiliang; Chen, Mingmin; Lissner, Simone; Gessner, Johannes E; Donowitz, Mark; Yun, C Chris; deJonge, Hugo; Lamprecht, Georg; Seidler, Ursula

2013-01-01

Trafficking, brush border membrane (BBM) retention, and signal-specific regulation of the Na+/H+ exchanger NHE3 is regulated by the Na+/H+ Exchanger Regulatory Factor (NHERF) family of PDZ-adaptor proteins, which enable the formation of multiprotein complexes. It is unclear, however, what determines signal specificity of these NHERFs. Thus, we studied the association of NHE3, NHERF1 (EBP50), NHERF2 (E3KARP), and NHERF3 (PDZK1) with lipid rafts in murine small intestinal BBM. Detergent resistant membranes ("lipid rafts") were isolated by floatation of Triton X-incubated small intestinal BBM from a variety of knockout mouse strains in an Optiprep step gradient. Acid-activated NHE3 activity was measured fluorometrically in BCECF-loaded microdissected villi, or by assessment of CO2/HCO3(-) mediated increase in fluid absorption in perfused jejunal loops of anethetized mice. NHE3 was found to partially associate with lipid rafts in the native BBM, and NHE3 raft association had an impact on NHE3 transport activity and regulation in vivo. NHERF1, 2 and 3 were differentially distributed to rafts and non-rafts, with NHERF2 being most raft-associated and NHERF3 entirely non-raft associated. NHERF2 expression enhanced the localization of NHE3 to membrane rafts. The use of acid sphingomyelinase-deficient mice, which have altered membrane lipid as well as lipid raft composition, allowed us to test the validity of the lipid raft concept in vivo. The differential association of the NHERFs with the raft-associated and the non-raft fraction of NHE3 in the brush border membrane is one component of the differential and signal-specific NHE3 regulation by the different NHERFs. © 2013 S. Karger AG, Basel.

An ace up their sleeve: a transcriptomic approach exposes the AceI efflux protein of Acinetobacter baumannii and reveals the drug efflux potential hidden in many microbial pathogens

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Karl A Hassan

2015-04-01

Full Text Available The era of antibiotics as a cure-all for bacterial infections appears to be coming to an end. The emergence of multidrug resistance in many hospital-associated pathogens has resulted in superbugs that are effectively untreatable. Multidrug efflux pumps are well known mediators of bacterial drug resistance. Genome sequencing efforts have highlighted an abundance of putative efflux pump genes in bacteria. However, it is not clear how many of these pumps play a role in antimicrobial resistance. Several studies have demonstrated that efflux pump genes that participate in drug resistance are typically under tight regulatory control and expressed only in response to their substrates. Consequently, changes in gene expression following antimicrobial shock treatments may be used to identify efflux pumps that mediate antimicrobial resistance, informing targeted functional analyses of these proteins. Using this approach we have characterised novel efflux pumps in both Gram-negative and Gram-positive bacteria. Notably, we recently applied this strategy to characterise the AceI efflux pump from Acinetobacter. AceI is a prototype for a new family of multidrug efflux proteins that is conserved across many proteobacterial lineages. Different efflux pumps in this family have been shown to confer resistance to biocides including chlorhexidine, dequalinium, benzalkonium, proflavine and/or acriflavine. The discovery of this novel family of multidrug efflux proteins raises the possibility that additional undiscovered intrinsic resistance proteins may be encoded in the core genomes of pathogenic bacteria.

Enhanced resistance in Theobroma cacao against oomycete and fungal pathogens by secretion of phosphatidylinositol-3-phosphate-binding proteins.

Science.gov (United States)

Helliwell, Emily E; Vega-Arreguín, Julio; Shi, Zi; Bailey, Bryan; Xiao, Shunyuan; Maximova, Siela N; Tyler, Brett M; Guiltinan, Mark J

2016-03-01

The internalization of some oomycete and fungal pathogen effectors into host plant cells has been reported to be blocked by proteins that bind to the effectors' cell entry receptor, phosphatidylinositol-3-phosphate (PI3P). This finding suggested a novel strategy for disease control by engineering plants to secrete PI3P-binding proteins. In this study, we tested this strategy using the chocolate tree Theobroma cacao. Transient expression and secretion of four different PI3P-binding proteins in detached leaves of T. cacao greatly reduced infection by two oomycete pathogens, Phytophthora tropicalis and Phytophthora palmivora, which cause black pod disease. Lesion size and pathogen growth were reduced by up to 85%. Resistance was not conferred by proteins lacking a secretory leader, by proteins with mutations in their PI3P-binding site, or by a secreted PI4P-binding protein. Stably transformed, transgenic T. cacao plants expressing two different PI3P-binding proteins showed substantially enhanced resistance to both P. tropicalis and P. palmivora, as well as to the fungal pathogen Colletotrichum theobromicola. These results demonstrate that secretion of PI3P-binding proteins is an effective way to increase disease resistance in T. cacao, and potentially in other plants, against a broad spectrum of pathogens. © 2015 Society for Experimental Biology, Association of Applied Biologists and John Wiley & Sons Ltd.

An ochre mutation in the vitamin D receptor gene causes hereditary 1,25-dihydroxyvitamin D sub 3 -resistant rickets in three families

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Ritchie, H.H.; Hughes, M.R.; Thompson, E.T.; Pike, J.W.; O' Malley, B.W. (Baylor College of Medicine, Houston, TX (USA)); Malloy, P.J.; Feldman, D. (Stanford Univ. School of Medicine, CA (USA)); Hochberg, Z. (Rambam Medical Center, Haifa (Israel))

1989-12-01

Hereditary 1,25-dihydroxyvitamin D{sub 3}-resistant rickets is a rare autosomal-recessive disease resulting from target-organ resistance to the action of the active hormonal form of vitamin D. Four affected children from three related families with the classical syndrome of hereditary 1,25-dihydroxyvitamin D{sub 3}-resistant rickets and the absence of detectable binding to the vitamin D receptor (VDR) in cultured fibroblasts or lymphoblasts were examined for genetic abnormalities in the VDR gene. Genomic DNA from Epstein-Barr virus-transformed lymphoblasts of eight family members was isolated and amplified by polymerase chain reaction techniques. Amplified fragments containing the eight structural exons encoding the VDR protein were sequenced. The DNA from all affected children exhibited a single C {yields} A base substitution within exon 7 at nucleotide 970. Although the affected children were all homozygotic for the mutation, the four parents tested all exhibited both wild-type and mutant alleles, indicating a heterozygous state. Recreated mutant receptor exhibited no specific 1,25-({sup 3}H)dihydroxyvitamin D{sub 3} binding and failed to activate a cotransfected VDR promoter-reporter gene construct. Thus these findings identify an ochre mutation in a human steroid hormone receptor in patients with hereditary 1,25-dihydroxyvitamin D{sub 3}-resistant rickets.

Contemporary Issues in Protein Requirements and Consumption for Resistance Trained Athletes

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Wilson Jacob

2006-06-01

Full Text Available Abstract In recent years an explosion of research papers concerning protein consumption has been published. The need to consolidate this information has become critical from both practical and future research standpoints. For this reason, the following paper presents an in depth analysis of contemporary issues in protein requirements and consumption for resistance trained athletes. Specifically, the paper covers: 1. protein requirements for resistance trained athletes; 2. the effect of the digestion rate of protein on muscular protein balance; 3. the optimal timing of protein intake relative to exercise; 4. the optimal pattern of protein ingestion, relative to how an individual should consume their protein throughout a 24 hour period, and what sources are utilized during this time frame; 5. protein composition and its interaction with measures of protein balance and strength performance; 6. the combination of protein and carbohydrates on plasma insulin levels and protein balance; 7. the efficacy of protein supplements and whole food protein sources. Our goal is to provide the reader with practical information in optimizing protein intake as well as for provision of sound advice to their clients. Finally, special care was taken to provide future research implications.

Familial adult spinal muscular atrophy associated with the VAPB gene: report of 42 cases in Brazil

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Victor Kosac

2013-10-01

Full Text Available Familial spinal muscular atrophy (FSMA associated with the vesicle-associated membrane protein-associated protein B (VAPB gene is a rare autosomal dominant disease with late onset and slow progression. We studied 10 of 42 patients from 5 families by taking clinical histories and performing physical exams, electrophysiological studies, and genetic tests. All patients presented late onset disease with slow progression characterized by fasciculations, proximal weakness, amyotrophy, and hypoactive deep tendon reflex, except two who exhibited brisk reflex. Two patients showed tongue fasciculations and respiratory insufficiency. Electrophysiological studies revealed patterns of lower motor neuron disease, and genetic testing identified a P56S mutation of the VAPB gene. Although it is a rare motor neuron disease, FSMA with this mutation might be much more prevalent in Brazil than expected, and many cases may be undiagnosed. Genetic exams should be performed whenever it is suspected in Brazil.