663 research outputs found

    Myostatin-2 gene structure and polymorphism of the promoter and first intron in the marine fish Sparus aurata: evidence for DNA duplications and/or translocations

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    <p>Abstract</p> <p>Background</p> <p>Myostatin (MSTN) is a member of the transforming growth factor-ß superfamily that functions as a negative regulator of skeletal muscle development and growth in mammals. Fish express at least two genes for <it>MSTN</it>: <it>MSTN-1 </it>and <it>MSTN-2</it>. To date, <it>MSTN-2 </it>promoters have been cloned only from salmonids and zebrafish.</p> <p>Results</p> <p>Here we described the cloning and sequence analysis of <it>MSTN-2 </it>gene and its 5' flanking region in the marine fish <it>Sparus aurata </it>(sa<it>MSTN-2</it>). We demonstrate the existence of three alleles of the promoter and three alleles of the first intron. Sequence comparison of the promoter region in the three alleles revealed that although the sequences of the first 1050 bp upstream of the translation start site are almost identical in the three alleles, a substantial sequence divergence is seen further upstream. Careful sequence analysis of the region upstream of the first 1050 bp in the three alleles identified several elements that appear to be repeated in some or all sequences, at different positions. This suggests that the promoter region of sa<it>MSTN-2 </it>has been subjected to various chromosomal rearrangements during the course of evolution, reflecting either insertion or deletion events. Screening of several genomic DNA collections indicated differences in allele frequency, with allele 'b' being the most abundant, followed by allele 'c', whereas allele 'a' is relatively rare. Sequence analysis of sa<it>MSTN-2 </it>gene also revealed polymorphism in the first intron, identifying three alleles. The length difference in alleles '1R' and '2R' of the first intron is due to the presence of one or two copies of a repeated block of approximately 150 bp, located at the 5' end of the first intron. The third allele, '4R', has an additional insertion of 323 bp located 116 bp upstream of the 3' end of the first intron. Analysis of several DNA collections showed that the '2R' allele is the most common, followed by the '4R' allele, whereas the '1R' allele is relatively rare. Progeny analysis of a full-sib family showed a Mendelian mode of inheritance of the two genetic loci. No clear association was found between the two genetic markers and growth rate.</p> <p>Conclusion</p> <p>These results show for the first time a substantial degree of polymorphism in both the promoter and first intron of <it>MSTN-2 </it>gene in a perciform fish species which points to chromosomal rearrangements that took place during evolution.</p

    Vitamin A affects flatfish development in a thyroid hormone signaling and metamorphic stage dependent manner

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    Vitamin A (VA) and retinoid derivatives are known morphogens controlling vertebrate development. Despite the research effort conducted during the last decade, the precise mechanism of how VA induces post-natal bone changes, and particularly those operating through crosstalk with the thyroid hormones (THs) remain to be fully understood. Since effects and mechanisms seem to be dose and time-dependent, flatfish are an interesting study model as they undergo a characteristic process of metamorphosis driven by THs that can be followed by external appearance. Here, we studied the effects of VA imbalance that might determine Senegalese sole (Solea senegalensis) skeletogenetic phenotype through development of thyroid follicles, THs homeostasis and signaling when a dietary VA excess was specifically provided during pre-, pro-or post-metamorphic stages using enriched rotifers and Artemia as carriers. The increased VA content in enriched live prey was associated to a higher VA content in fish at all developmental stages. Dietary VA content clearly affected thyroid follicle development, T3 and T4 immunoreactive staining, skeletogenesis and mineralization in a dose and time-dependent fashion. Gene expression analysis showed that VA levels modified the mRNA abundance of VA- and TH-specific nuclear receptors at specific developmental stages. Present results provide new and key knowledge to better understand how VA and TH pathways interact at tissue, cellular and nuclear level at different developmental periods in Senegalese sole, unveiling how dietary modulation might determine juvenile phenotype and physiology.Ministry of Education and Culture (MEC) of the Spanish Government [AGL2005-02478]; [SFRH/BPD/82049/2011]info:eu-repo/semantics/publishedVersio

    Entangled Stories: The Red Jews in Premodern Yiddish and German Apocalyptic Lore

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    “Far, far away from our areas, somewhere beyond the Mountains of Darkness, on the other side of the Sambatyon River…there lives a nation known as the Red Jews.” The Red Jews are best known from classic Yiddish writing, most notably from Mendele's Kitser masoes Binyomin hashlishi (The Brief Travels of Benjamin the Third). This novel, first published in 1878, represents the initial appearance of the Red Jews in modern Yiddish literature. This comical travelogue describes the adventures of Benjamin, who sets off in search of the legendary Red Jews. But who are these Red Jews or, in Yiddish, di royte yidelekh? The term denotes the Ten Lost Tribes of Israel, the ten tribes that in biblical times had composed the Northern Kingdom of Israel until they were exiled by the Assyrians in the eighth century BCE. Over time, the myth of their return emerged, and they were said to live in an uncharted location beyond the mysterious Sambatyon River, where they would remain until the Messiah's arrival at the end of time, when they would rejoin the rest of the Jewish people. This article is part of a broader study of the Red Jews in Jewish popular culture from the Middle Ages through modernity. It is partially based on a chapter from my book, Umstrittene Erlöser: Politik, Ideologie und jüdisch-christlicher Messianismus in Deutschland, 1500–1600 (Göttingen: Vandenhoeck & Ruprecht, 2011). Several postdoctoral fellowships have generously supported my research on the Red Jews: a Dr. Meyer-Struckmann-Fellowship of the German Academic Foundation, a Harry Starr Fellowship in Judaica/Alan M. Stroock Fellowship for Advanced Research in Judaica at Harvard University, a research fellowship from the Heinrich Hertz-Foundation, and a YIVO Dina Abramowicz Emerging Scholar Fellowship. I thank the organizers of and participants in the colloquia and conferences where I have presented this material in various forms as well as the editors and anonymous reviewers of AJS Review for their valuable comments and suggestions. I am especially grateful to Jeremy Dauber and Elisheva Carlebach of the Institute for Israel and Jewish Studies at Columbia University, where I was a Visiting Scholar in the fall of 2009, for their generous encouragement to write this article. Sue Oren considerably improved my English. The style employed for Romanization of Yiddish follows YIVO's transliteration standards. Unless otherwise noted, translations from the Yiddish, Hebrew, German, and Latin are my own. Quotations from the Bible follow the JPS translation, and those from the Babylonian Talmud are according to the Hebrew-English edition of the Soncino Talmud by Isidore Epstein

    The C313Y Piedmontese mutation decreases myostatin covalent dimerisation and stability

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    <p>Abstract</p> <p>Background</p> <p>Myostatin is a key negative regulator of muscle growth and development, whose activity has important implications for the treatment of muscle wastage disorders. Piedmontese cattle display a double-muscled phenotype associated with the expression of C313Y mutant myostatin. <it>In vivo</it>, C313Y myostatin is proteolytically processed, exported and circulated extracellularly but fails to correctly regulate muscle growth. The C313Y mutation removes the C313-containing disulphide bond, an integral part of the characteristic TGF-β cystine-knot structural motif.</p> <p>Results</p> <p>Here we present <it>in vitro </it>analysis of the structure and stability of the C313Y myostatin protein that reveals significantly decreased covalent dimerisation for C313Y myostatin accompanied by a loss of structural stability compared to wild type. The C313Y myostatin growth factor, processed from full length precursor protein, fails to inhibit C2C12 myoblast proliferation in contrast to wild type myostatin. Although structural modeling shows the substitution of tyrosine causes structural perturbation, biochemical analysis of additional disulphide mutants, C313A and C374A, indicates that an intact cystine-knot motif is a major determinant in myostatin growth factor stability and covalent dimerisation.</p> <p>Conclusions</p> <p>This research shows that the cystine-knot structure is important for myostatin dimerisation and stability, and that disruption of this structural motif perturbs myostatin signaling.</p

    Transient up- and down-regulation of expression of myosin light chain 2 and myostatin mRNA mark the changes from stratified hyperplasia to muscle fiber hypertrophy in larvae of gilthead sea bream (Sparus aurata L.)

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    Hyperplasia and hypertrophy are the two mechanisms by which muscle develops and grows. We study these two mechanisms, during the early development of white muscle in Sparus aurata, by means of histology and the expression of structural and regulatory genes. A clear stage of stratified hyperplasia was identified early in the development of gilthead sea bream but ceased by 35 dph when hypertrophy took over. Mosaic recruitment of new white fibers began as soon as 60 dph. The genes mlc2a and mlc2b were expressed at various levels during the main phases of hyperplasia and hypertrophy. The genes myog and mlc2a were significantly up-regulated during the intensive stratified formation of new fibers and their expression was significantly correlated. Expression of mstn1 and igf1 increased at 35 dph, appeared to regulate the hyperplasia-to-hypertrophy transition, and may have stimulated the expression of mlc2a, mlc2b and col1a1 at the onset of mosaic hyperplasia. The up-regulation of mstn1 at transitional phases in muscle development indicates a dual regulatory role of myostatin in fish larval muscle growth

    The intrafamilial transmission of rheumatoid arthritis--IV : Recalled parent-child relations by rheumatoid arthritics and controls

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    The study is based on data from three survey interviews, taken four months apart, on adults over 30 yr old. Subjects were drawn both from a National sample of the United States and a Clinic sample in Ann Arbor. The results indicate that females with rheumatoid arthritis, in contrast to controls without RA, reported mothers who were more arbitrary in authority, and toward whom the daughter felt more covert hostility but showed less overt aggressiveness. Nevertheless, RA females rated their mothers as strong role models as did the non-RA women. No such differences with the father were evident. Female RA's also showed the lowest childhood self-esteem score, compared to female controls and males. By contrast, RA males reported a more positive image of the mother toward whom less covert hostility was felt. No such differences in the father-child relations were seen.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/32907/1/0000287.pd

    Insulin-like growth factor-I binds in the inner plexiform layer and circumferential germinal zone in the retina of the goldfish

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    Results of the previous study suggest that insulin-related peptides regulate proliferation of retinal progenitors in the adult goldfish. Because of their known roles in retinal neurogenesis, we have chosen to focus future studies on insulin-like growth factor I (IGF-I) and the IGF-I receptor. In the study described here, we characterized the spatial distribution and specificity of IGF-I binding sites in the retina of the adult goldfish by performing receptor-binding autoradiography with [ 125 I]-IGF-I alone and with unlabeled IGF-I-related molecules (IGF-I, IGF-II, insulin, and des-[1-3]-IGF-I) as competitive inhibitors of [ 125 I]-IGF-I binding. The results of these experiments show that IGF-I binds in two locations in the retina of the adult goldfish, within the inner plexiform layer of the differentiated retina and the circumferential germinal zone. The competition experiments suggest that [ 125 I]-IGF-I binds at sites specific for IGF-I, and that both IGF-I receptors and IGF-I binding proteins are present in the retina. J. Comp. Neurol. 394:395–401, 1998. © 1998 Wiley-Liss, Inc.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/34449/1/10_ftp.pd
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