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Hormone Gene (hormone + gene)
Selected AbstractsMyocyte enhancer factor 2 (MEF2) is a key modulator of the expression of the prothoracicotropic hormone gene in the silkworm, Bombyx moriFEBS JOURNAL, Issue 15 2005Kunihiro Shiomi Prothoracicotropic hormone (PTTH) plays a central role in controlling molting, metamorphosis, and diapause termination in insects by stimulating the prothoracic glands to synthesize and release the molting hormone, ecdysone. Using Autographa californica nucleopolyhedrovirus (AcNPV)-mediated transient gene transfer into the central nervous sytem (CNS) of the silkworm, Bombyx mori, we identified two cis -regulatory elements that participate in the decision and the enhancement of PTTH gene expression in PTTH-producing neurosecretory cells (PTPCs). The cis -element mediating the enhancement of PTTH gene expression binds the transcription factor Bombyx myocyte enhancer factor 2 (BmMEF2). The BmMEF2 gene was expressed in various tissues including the CNS. In brain, the BmMEF2 gene was expressed at elevated levels in two types of lateral neurosecretory cells, namely PTPCs and corazonin-like immunoreactive lateral neurosecretory cells. Overexpression of BmMEF2 cDNA caused an increase in the transcription of PTTH. Therefore, BmMEF2 appears to be particularly important in the brain where it is responsible for the differentiation of lateral neurosecretory cells, including the enhancement of PTTH gene expression. This is the first report to identify a target gene of MEF2 in the invertebrate nervous system. [source] Variable number of tandem repeats in the growth hormone gene of Sparus aurata: association with growth and effect on gene transcriptionJOURNAL OF FISH BIOLOGY, Issue 2004R. Almuly The GH gene of Sparus aurata(saGH) contains variable number of tandem repeats (VNTR). The hyper-variable minisatellites in the first and third introns segregate in a Mendelian manner and exhibit numerous alleles. Analysis by PCR and sequencing of the two introns in several wild Sparidae species revealed comparable minisatellites with some variations. ,Zoo blot' with the first intron unit as a probe showed this sequence to be characteristic of several families from the Perciformes order. Unexpectedly, a similar minisatellite was found in the first intron of the GH gene in flounder, which belongs to a different order. Transfection of constructs containing a reporter gene and first intron of different length to four cell lines resulted in an inhibitory effect of the longer intron relative to the short intron. A (CA)n microsatellite (saGHpCA) is found in the GH promoter. A similar repeat at the same location is present in GH promoters of several other fish species. High variability (11 alleles) of the saGHpCA was found in a hatchery population. Full-sib family genotyping showed a Mendelian inheritance of these alleles. A significant association was found between allele distribution and body mass in large and average size fishes from a hatchery population. The intron minisatellites may serve as markers for hybrid population and parental assignment. Its presence in families and orders of the higher teleosts may help solving classification uncertainties. Their conservation and inhibitory effect suggest a biological role. The saGHpCA is correlated with growth and may be a good candidate for predicting growth performance. [source] Premature translation of transition protein 2 mRNA causes sperm abnormalities and male infertilityMOLECULAR REPRODUCTION & DEVELOPMENT, Issue 3 2007Khailun Tseden Abstract During mammalian spermiogenesis somatic histones are replaced at first by transition proteins, which are in turn replaced by the protamines, forming the sperm nucleoprotamines. It is believed that transition protein 2 (Tnp2) is necessary for maintaining the normal processing of protamines and, consequently, the completion of chromatin condensation. The transition protein mRNAs are stored in translationally inert messenger ribonucleoprotein particles for up to 7 days until translational activation in elongated spermatids. Substantial evidence suggests an involvement of 3,untranslated region (UTR) in the translational regulation of the Tnp2 mRNAs. In order to determine the role of Tnp2 3,UTR in translational regulation and to study whether the translational repression of Tnp2 mRNA is necessary for normal spermatid differentiation in mice, we generated transgenic mice that carry a Tnp2-hGH transgene. In this transgene, 3,UTR of Tnp2 gene was replaced by 3, 3,UTR of human growth hormone gene. In these transgenic animals, transcription and translation of Tnp2 occur simultaneously in round spermatids which is an evidence for involvement of Tnp2 3,UTR in its translation repression. Premature translation of Tnp2 mRNA caused abnormal head morphogenesis, reduced sperm motility and male infertility. These results show clearly that a strict temporal and stage-specific Tnp2 translation is necessary for the correct differentiation of round spermatids into mature spermatozoa and for male fertility. Mol. Reprod. Dev. © 2006 Wiley-Liss, Inc. [source] Single nucleotide polymorphisms in the corticotrophin - releasing hormone and pro - opiomelancortin genes are associated with growth and carcass yield in beef cattleANIMAL GENETICS, Issue 2 2005F. C. Buchanan Summary A single nucleotide polymorphism (SNP) in the corticotrophin - releasing hormone gene (CRH C22G) alters the fourth amino acid in the signal sequence from proline to arginine. Two other SNPs (CRH A145G and C240G) occur in the propeptide region at residue positions 45 and 77, respectively, that result in serine/asparagine and histidine/aspartic acid substitutions respectively. These SNPs, as well as SNPs in pro - opiomelancortin (POMC), leptin (LEP) and melanocortin - 4 receptor (MC4R), were evaluated for associations with average daily gain, end-of-test rib-eye area, shipping weight and hot carcass weight in a group of 256 steers using a general linear model. The CRH C22G SNP was associated with end-of-test rib-eye area (P < 0.034) and hot carcass weight (P < 0.0015). The SNP in POMC was associated with shipping weight (P < 0.0078) and hot carcass weight (P = 0.006) while it approached significance for average daily gain (P < 0.07). The SNP in MC4R approached significance for hot carcass weight (P < 0.085) while no significance was observed between the leptin SNP and the above listed traits. Because both CRH and POMC regulate appetite, potential interaction effects between these two genes were assessed. The absence of an interaction effect between CRH and POMC with hot carcass weight suggests that these genes act independently to increase carcass yield. These gene effects used singularly or together could result in an economic benefit to the beef industry. [source] Characterization of two melanin-concentrating hormone genes in zebrafish reveals evolutionary and physiological links with the mammalian MCH systemTHE JOURNAL OF COMPARATIVE NEUROLOGY, Issue 5 2009Jennifer R. Berman Abstract Melanin-concentrating hormone (MCH) regulates feeding and complex behaviors in mammals and pigmentation in fish. The relationship between fish and mammalian MCH systems is not well understood. Here, we identify and characterize two MCH genes in zebrafish, Pmch1 and Pmch2. Whereas Pmch1 and its corresponding MCH1 peptide resemble MCH found in other fish, the zebrafish Pmch2 gene and MCH2 peptide share genomic structure, synteny, and high peptide sequence homology with mammalian MCH. Zebrafish Pmch genes are expressed in closely associated but non-overlapping neurons within the hypothalamus, and MCH2 neurons send numerous projections to multiple MCH receptor-rich targets with presumed roles in sensory perception, learning and memory, arousal, and homeostatic regulation. Preliminary functional analysis showed that whereas changes in zebrafish Pmch1 expression correlate with pigmentation changes, the number of MCH2-expressing neurons increases in response to chronic food deprivation. These findings demonstrate that zebrafish MCH2 is the putative structural and functional ortholog of mammalian MCH and help elucidate the nature of MCH evolution among vertebrates. J. Comp. Neurol. 517:695,710, 2009. © 2009 Wiley-Liss, Inc. [source] | ||||||||||