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Growth Hormone Receptor (growth + hormone_receptor)
Selected AbstractsGenetic diversity of growth hormone receptor gene in cattleANIMAL SCIENCE JOURNAL, Issue 5 2009Bang Zhong LIN ABSTRACT Growth hormone receptor (GHR) belongs to a member of the cytokine receptor superfamily. Polymorphism of presence or absence of an approximately 1.2 kbp LINE-1 element is observed in bovine GHR gene. The present study was carried out for estimating the genetic diversity and the origin of the LINE-1 element in 10 European, Southeastern Asian and East Asian cattle breeds or populations. Genotyping of the LINE-1 revealed predominant LINE-1 presence in European breeds (0.917,0.991), absence in the Bos taurus indicus populations (0.000,0.017), and intermediate presence in Northeast Asian cattle (0.417,0.522). From genetic features of LINE families, LINE-1 of GHR could be attributed to the same origin in both European and Asian cattle, and Asian LINE-1 may not be derived from recent introgression. This result suggested that LINE-1 in bovine GHR gene could have arisen in an ancestral population of Bos taurus taurus. [source] Growth hormone excess and the development of growth hormone receptor antagonistsEXPERIMENTAL PHYSIOLOGY, Issue 11 2008C. E. Higham In 1990, a single amino acid substitution in the growth hormone (GH) gene at position 119 was found to transform the consequent protein from an agonist to an antagonist at the growth hormone receptor (GHR). Further amino acid substitutions plus prolongation of the half-life of the protein by pegylation resulted in the first clinically effective GHR antagonist, pegvisomant. Following extensive clinical trials, this medication has emerged as the most efficacious therapy for treatment-resistant acromegaly. Subsequent advances in our understanding of GH,GHR interactions and downstream GH signalling pathways suggest that pegvisomant binds to preformed GHR dimers and prevents rotational changes within the receptor,GH complex necessary for intracellular signalling to occur. This article reviews the discovery of pegvisomant, from initial experimental data to successful licensing of the drug for treatment-resistant acromegaly, and discusses its other potential therapeutic uses in diseases with abnormalities in the GH,IGF-I axis. [source] Analysis of growth hormone receptor polymorphism in Japanese semisuper centenariansGERIATRICS & GERONTOLOGY INTERNATIONAL, Issue 2 2006Yuchen Du Background: Recent studies have demonstrated a significant association between mutations in genes involved in the GHR/IGF1 signaling pathway and extension of the lifespan of model organisms. Exon 3 insertion or deletion is one common polymorphism in the growth hormone receptor (GHR) of humans. The exon 3 deletion allele is reported to have stronger signaling in the GH/GHR pathway, which may correlate to short lifespan. Methods: We investigated the common polymorphic variation in 119 Japanese semisuper centenarians (SSC; older than 105) compared with 104 healthy younger controls via the polymorphism-based polymerase chain reaction method. Results: The frequency of exon 3 deletion variation of GHR in SSC was found to be higher than controls, although this was not significant statistically. Also, the single nucleotide polymorphism genotype frequency and allele frequency exhibited no differences between SSC and controls. Conclusions: These results show that SSC in Japan do not tend to have the allele of GHR, which has a lower signaling capacity. [source] Effects of vegetable feed ingredients on bone health in Atlantic salmonJOURNAL OF APPLIED ICHTHYOLOGY, Issue 2 2010P. G. Fjelldal Summary The aim of the present study was to examine if dietary inclusion of vegetable lipids (VL) and proteins (VP) influenced markers of bone health in Atlantic salmon. Triplicate groups were fed one of four different diets; 100% fish protein (FP) and fish lipids (FL) (FPFL), 80% VP and 35% VL (80VP35VL), 40% VP and 70% VL (40VP70VL), or 80% VP and 70% VL (80VP70VL) for 12 months on-growth in sea water. Fish were analyzed for vertebral bone mineralization (mineral content, as % of bone dry weight), vertebral deformities (radiology), vertebral bone mRNA expression of factors involved in mineralization (bone gla protein, bgp) and growth regulation (igf-I and growth hormone receptor), as well as plasma vitamin D metabolites. The fish grew from 0.35 to 4 kg during the experimental period. At the end of the experiment, significantly lower prevalence of fish with one or more deformed vertebrae was observed in the 80VP70VL group (11%) compared to the other groups (33,43%). There was a significant higher relative expression of igf -I mRNA in vertebral bone of fish fed the 80VP70VL diet compared to control fish (FPFL), while the other genes studied were unaffected. Elevated plasma 25-hydroxyvitamin D3 recorded in the marine feed group is discussed as a predictor for later development of bone deformities. In conclusion, the present study shows that high inclusion levels of vegetable lipids and proteins may have a positive effect on bone health in Atlantic salmon postsmolts. [source] Expression of growth hormone receptor in benign and malignant cutaneous proliferative entities ,JOURNAL OF CUTANEOUS PATHOLOGY, Issue 6 2000Manuel Ginarte The skin has the necessary elements to respond to growth hormone (GH) and suffers clinical changes in the pathological circumstances of excess and deficiency of GH. The GH has been involved in the development of different types of human neoplasms. Based on these data, we have studied the GH receptor (GHR) expression in acrochordons, seborrheic keratosis, melanocytic nevi, histiocytomas, squamous cell carcinomas, basal cell carcinomas, and malignant melanomas by means of the immunohistochemistry with the monoclonal antibody MAb 263. All the entities showed immunoreactivity for GHR. In the histiocytomas, the expression of GHR in the keratinocytes of the hyperplastic epidermis coating the lesion showed a strong nuclear pattern, but the non-hyperplastic epidermis of the edges of the histiocytomas expressed GHR with a cytoplasmic pattern. In the basal cell carcinoma and squamous cell carcinoma, the immunoreactivity was weaker than in normal skin. In the squamous cell carcinoma, the intensity of immunostaining correlated directly with the grade of cellular differentation. In conclusion, the GH may be involved in the development of different kinds of cutaneous neoplasms, and the intracellular localization of GHR may imply a functional significance, at least in the histiocytomas. [source] Effects of DGAT1 and GHR on milk yield and milk composition in the Chinese dairy populationANIMAL GENETICS, Issue 6 2009D. Sun Summary Previous studies have demonstrated that the p.Lys232Ala substitution in the acylCoA: diacylglycerol acyltransferase (DGAT1) gene and the p.Phe279Tyr mutation in the growth hormone receptor (GHR) gene are the causative quantitative trait loci underlying milk yield and composition on BTA14 and BTA20 respectively. To examine their applications in the genetic improvement of Chinese dairy cattle productivity, we herein investigated the effects of the DGAT1 p.Lys232Ala and GHR p.Phe279Tyr mutations on milk, fat and protein yield, as well as fat and protein percentage in the milk of 1222 Holstein cows. Genotyping was performed using PCR-RFLP for DGAT1 or primer-introduced restriction analysis (PCR-PIRA) for GHR. With a mixed animal model, the significant associations of the DGAT1 p.Lys232Ala substitution with 305-day milk, fat and protein yield were identified (P = 0.0001). The DGAT1 allele that encode lysine at position 232 was associated with increased 305-day milk fat yield, but with decreased 305-day milk and protein yield, whereas the GHR p.Phe279Tyr mutation was found to be significantly associated with protein percentage (P = 0.0014). The allele substitution effect of p.279Phe by p.279Tyr may lead to a significant increase in protein percentage. Our findings indicate that DGAT1 p.232Ala and GHR p.279Phe could be used to increase milk yield and protein yield of Chinese Holstein cows. [source] The effects of polymorphisms in the DGAT1, leptin and growth hormone receptor gene loci on body energy, blood metabolic and reproductive traits of Holstein cowsANIMAL GENETICS, Issue 1 2009G. Oikonomou Summary The objective of this study was to examine the impact of polymorphisms in the acyl-CoA:diacylglycerol acyltransferase (DGAT1), leptin and growth hormone receptor genes on body energy (body condition score, total body energy content and cumulative effective energy balance) and blood metabolic traits (levels of ,-hydroxybutyrate, glucose and non-esterified fatty acids), measured once before the first calving and then repeatedly throughout first lactation in 497 Holstein cows. The influence of the same polymorphisms on cow reproductive performance and health during the first and second lactations was also assessed. Several reproductive traits were considered including interval, conception and insemination traits, as well as incidence of metritis and reproductive problems. Genotyping was performed using PCR-RFLP (DGAT1, leptin) or allele-specific PCR (growth hormone receptor). For each locus, the effect of allele substitution on body energy and blood metabolic traits was estimated using random regression models. The same effect on reproductive traits was assessed with single-trait mixed linear models. Significant (P < 0.05) effects on specific reproductive traits were observed. DGAT1 and growth hormone receptor alleles responsible for significant increases in milk production were found to have an adverse effect on reproduction, while the leptin allele responsible for significant increase in milk production was linked to marginally increased metritis frequency. Furthermore, the three studied loci were also found to significantly (P < 0.05) affect certain body energy and blood metabolic traits. Several associations are published for the first time, but these should be confirmed by other investigators before the polymorphisms are used in gene-assisted selection. [source] The somatotropic axis of the dairy cow revisitedANIMAL SCIENCE JOURNAL, Issue 1 2002Michael Terence ROSE ABSTRACT The greater understanding of the somatotropic axis in the lactating dairy cow that has been achieved in recent years is briefly reviewed in this article. Specifically discussed are: the significance of multiple forms of insulin-like growth factor messenger RNA (ribonucleic acid) caused by alternative splicing, and the possible functions of the various translated extension proteins; the possible roles of multiple sites of growth hormone secretion other than in the pituitary, and the implications for possible autocrine or paracrine growth hormone secretion; the consequences for increased circulating growth hormone half-life, and possibly biological effectiveness, caused by growth hormone binding proteins; and the increasing evidence for the presence of growth hormone receptors in the bovine mammary gland. The need for further research is highlighted in the present review; published information regarding the bovine, in many of these areas, is still largely insufficient. [source] | |||||||||||||