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猪胰岛素样生长因子Ⅰ基因表达与调控的研究进展 总被引：1，自引：0，他引：1
胰岛素样生长因子-Ⅰ(Ⅰ nsulin-like growth factor-Ⅰ,I GF-Ⅰ)是机体生长、发育和代谢的一个重要调控因子,同时也是生长激素(growth hormone,GH)启动生长活性的主要介导者.血液中的I GF-Ⅰ主要来源于肝脏,以内分泌的形式作用于其他组织;许多肝外组织也能合成I GF-Ⅰ,其主要以自分泌或旁分泌的形式发挥作用.多种因素调控其表达.本文就猪I GF-Ⅰ的表达与调控方面的最新研究进展进行一综述. 相似文献
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畜禽生长激素释放因子(GRF)的研究进展 总被引：4，自引：0，他引：4
生长激素释放因子(growth hormone- releasing factor,GRF)又称生长激素释放激素(growth hormone- releasinghorm one,GHRH) ,是存在于脊椎动物体内的一种生物活性多肽,由下丘脑合成并分泌,对脊椎动物的生长、发育及代谢调控起着极其重要的作用。其主要功能是,作为脑垂体生长激素(growth hormone,GH)的正性调控因子,能特异地诱导生长激素的合成与分泌,增高动物机体内的GH水平。而生长激素释放抑制因子(som atostain,SS)则抑制GH的合成与释放。GRF与其伴随的SS低谷诱发形成GH的分泌峰,峰的高度取决于GRF的强度及垂体对GRF的敏感… 相似文献
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本研究旨在探讨生长分化因子9(GDF9)及其受体在雄性成年狗睾丸中的定位与表达。采用RT-PCR、免疫组织化学法、免疫印迹法检测GDF9及其受体ALK5蛋白在成年狗睾丸中的表达与定位。GDF9蛋白在成年狗睾丸中的表达显示,GDF9阶段特异性地定位在成年狗睾丸生精上皮的圆形精细胞和粗线期精母细胞胞质。GDF9I型膜受体ALK5蛋白在成年狗睾丸中的表达显示,ALK5主要定位在圆形精细胞。本研究显示,GDF9及其膜受体ALK5在成年狗睾丸中均有表达,提示,GDF9由圆形精细胞和粗线期精母细胞特异性分泌,通过旁分泌形式调控支持细胞间紧密连接及支持细胞与生殖细胞间的细胞连接,并以自分泌形式调控生殖细胞的生长与迁移。 相似文献
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肌肉生长抑制素调控肌肉和脂肪组织代谢的研究进展 总被引：1，自引：0，他引：1
肌肉生长抑制素(myostatin,MSTN),又名生长分化因子-8(growth differentiation factor 8,GDF-8),是一种主要由骨骼肌分泌的蛋白质,在肌肉生长发育过程中起负调控作用。若MSTN基因编码区碱基突变或缺失,可以导致肌肉异常肥大,出现典型的"双肌"性状。近年来研究还发现,MSTN在脂肪组织中也表达,并在脂肪沉积的过程中发挥重要调控作用。因此,本文将从MSTN的基因结构、组织分布、作用机制以及功能等几个方面的相关研究进展进行综述,重点阐述其在肌肉和脂肪组织中的调控作用及机制,以期更深入了解MSTN,为畜牧业新品种的改良和肉质性状的改善奠定理论基础。 相似文献
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肌肉生长抑制素(myostatin,MSTN)基因也叫生长分化因子(growth differentiation factor-8,GDF8),其作为肌肉生长发育及分化的负向调控因子,可通过抑制正向调控因子--生肌决定因子(myogenic determination gene,MyoD)的转录活性来抑制成肌细胞的增殖和分化。MSTN基因在进化过程中具有较高的突变性,在不同动物中的表达量和表达范围均不相同。作者就该基因的表达、生物学功能、作用机制及在不同动物中的研究进展进行了详细阐述。 相似文献
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生长分化因子9(growth differentiation factor 9,GDF9)也称FecG基因,是影响家畜繁殖力的常染色体主效候选基因,此基因在性腺轴相关组织及内脏组织器官中均有表达,且shRNA下调GDF9基因的表达可能对动物生长轴的调控造成影响,因此,推测GDF9基因对动物正常的生长发育也具有重要作用。为探讨GDF9基因作为山羊生长性状候选基因的可能性,寻找与山羊生长性状相关的分子标记,本研究以陕北白绒山羊(n=638)为研究对象,并结合已有报道利用DNA池检测GDF9基因的InDel位点,评估InDel位点与生长性状的相关性。本研究发现,在638只陕北白绒山羊GDF9基因3′调控区存在12-bp的插入缺失(InDel),群体共出现3种基因型(II,ID,DD),其中I和D等位基因频率分别为0.461和0.539,优势基因型为杂合型(ID)频率为0.874。关联性分析结果表明,该突变位点与陕北白绒山羊体高显著相关(P<0.01),同时显著影响十字部高性状(P<0.05)。其他性状虽然没有显著的相关性,但是其体重、体长等重要生长性状也表现相同的趋势。因此,GDF9基因可作为陕北白绒山羊生长性状选育的候选基因,为陕北白绒山羊选育工作提供理论依据。 相似文献
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生长激素(growth hormone,GH)是由脑垂体前叶分泌的一种多肽激素,它作为一种特殊的生物活性蛋白促进机体合成代谢和蛋白质合成。GH传统的作用机制是垂体产生GH开始作用于膜受体,然后刺激肝脏胰岛素生长因子(insulin-like growth factor-1,IGF-1)生成,进而影响机体多个器官发育。近年的研究表明,GH除了内分泌作用途径,还可通过自分泌及旁分泌途径产生生物学效应。GH自分泌可以参与调控雄性和雌性动物生殖功能;GH自分泌对肌肉组织的代谢和生长也有重要影响,另外,GH自分泌与肿瘤的发生有密切的关系,其在一定程度上可以促进部分癌细胞的增殖,分化与迁移。通过对GH自分泌作用机制的研究有望发现自分泌GH在动物体内新的生物学作用,也有助于研究并治疗GH自分泌异常引发的相关疾病。 相似文献
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《广东畜牧兽医科技》2021,46(4)
生长分化因子8(Growth differentiation factor 8,GDF-8),又名肌肉生长抑制素(Myostatin,MSTN),是转化生长因子(Transforming growth factor,TGF)超家族中的一员,主要参与肌肉发育的负调控。近期研究发现GDF-8还参与生殖活动。本文通过了解GDF-8在生殖系统中的表达与定位,探索GDF-8在生殖配子的形成与胚胎发育中的作用,分析其对生殖活动的影响等方面,提出GDF-8基因不仅对于动物肌肉的生长发育有调控作用,而且在生殖活动方面也具有重要作用。本文为多角度认识GDF-8的生理与病理功能及其在生命活动中的作用提供新思路。 相似文献
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In several transformed cell lines, the growth factors IGF-I and epidermal growth factor (EGF) activate second messenger systems that cause the phosphorylation of the estrogen receptor (ER). One kinase catalysing receptor phosphorylation is mitogen activated protein (MAP) kinase, and the result of phosphorylation is an increase in receptor transactivation function. EGF and IGF-I, secreted locally and systemically, are involved in uterine-conceptus interactions in early pregnancy, and therefore it is of interest to determine whether these growth factors affect ER function in the uterus. An estrogen response element, chloramphenicol acetyl transferase reporter gene construct (CATERE) was transfected into bovine endometrial epithelial and stromal cells in vitro, and CAT measured during transient expression. Growth factors were added at various times following transfection, and MAP kinase phosphorylation was monitored by western blotting of p42 and p44. The MEK inhibitor U 0126 was used to determine whether the effect of IGF-I on CATERE expression was mediated through MAP kinase, and the anti-estrogen ICI 182780 was used to identify effects involving the ER. In stromal cells, reporter gene activity was increased in a dose dependent manner by IGF-I or hEGF in the presence or absence of estradiol-17beta. In the absence of estradiol the effect of IGF-I was not inhibited by ICI 182780. The effect of IGF-I occurred within an hour, before any detectable increase in cell proliferation, and the activation of CAT expression in response to IGF-I or EGF was blocked by U 0126. In contrast to their effects in stromal cells, neither IGF-I nor EGF affected CAT expression in bovine endometrial epithelial cells. Measurement of phosphorylated MAP kinases p42/p44 by western blotting showed that EGF but not IGF-I activated MAP kinase phosphorylation in both epithelial and stromal cells. In stromal cells, the fact that U 0126 blocked the CAT responses to IGF-I and EGF indicates the involvement of a MAP kinase. But since IGF-I did not activate p42/p44, a different MAP kinase, not detected by the antibody used here, is implicated. As the response was not blocked by ICI 182780, we conclude this effect is independent of ER activation. Therefore in bovine uterine cells in culture effects on MAP kinases p42/p44 can be dissociated from those on ERE-dependent gene expression, and reporter gene expression may be independent of ER activation. 相似文献
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Sosa C Abecia JA Carriquiry M Forcada F Martin GB Palacín I Meikle A 《Domestic animal endocrinology》2009,36(1):13-23
This study investigated whether a 27-day period of nutrition at half-maintenance during early pregnancy (up to Day 14) could alter maternal endocrine responses. Forty-six ewes were fed all or half of their maintenance requirements and slaughtered on Day 14 of the oestrous cycle or pregnancy. We used real time RT-PCR to study gene expression of growth hormone receptor (GHR) and leptin in adipose tissue and GHR, GHR1A and of the insulin-like growth factor I (IGF-I) in the liver. Blood profiles of metabolites and metabolic hormones were also determined. Throughout the experiment, underfed animals presented lower body weight and body condition, greater plasma concentrations of non-esterified fatty acids (NEFA), and lower plasma concentrations of leptin, compared to adequately fed animals. Undernutrition affected the patterns of gene expression in adipose and hepatic tissues, and the responses differed between pregnant and non-pregnant ewes. In adequately fed ewes, pregnancy up-regulated leptin mRNA expression in adipose tissue, a response that was impaired in underfed ewes. The hepatic expression of IGF-I mRNA was increased by pregnancy in underfed animals while no effect was observed in adequately fed ewes. It remains to be determined whether the changes in the endocrine milieu are paralleled by modifications in uterine gene expression that could alter the environment of the embryo during early pregnancy. 相似文献
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Luo ZF Fang XL Shu G Wang SB Zhu XT Gao P Chen LL Chen CY Xi QY Zhang YL Jiang QY 《Journal of animal science》2011,89(8):2356-2364
Sorbic acid (SA) is a PUFA with a conjugated double bond. The conjugated fatty acids, including CLA, are multifunctional bioactive fatty acids with the ability to improve growth performance. The effect of SA on pig growth performance was examined to determine its mechanism of action. The ADG, ADFI, and serum IGF-I concentration were examined, as were IGF-I secretion and IGF system gene expression in hepatocytes. Two hundred forty 21-d-old Duroc × Landrace × Yorkshire weaned piglets (6.86 ± 0.02 kg) were randomly divided into 4 groups, each consisting of 3 pens of 20 piglets (10 female and 10 male). The 4 groups of piglets were kept in a temperature-controlled room (26 to 28 °C), and feed and water were provided to the pigs ad libitum. Weanling piglets were fed diets that included 0, 0.5, 2, or 4 g of SA/kg for 42 d. The diet supplemented with 0.5 g/kg of SA improved (P < 0.05) ADG, BW, and G:F, whereas supplementation with all 3 SA doses increased (P < 0.05) ADG and G:F at 21 to 42 d of age. The greatest concentration of plasma triglycerides was observed (P < 0.05) in the 4 g/kg of SA group. The SA increased (0.5 g of SA/kg, P > 0.05; 1 g of SA/kg, P < 0.05; and 2 g of SA/kg, P < 0.05, respectively) plasma total serum protein and globulin concentrations in a dose-dependent manner. It was noted that the smallest SA treatment dose (0.5 g/kg) dramatically increased (P < 0.05) serum IGF-I concentration but decreased (P < 0.05) the concentrations of blood urea N and cortisol. The SA increased (P < 0.05) IGF-I, IGF-II, IGF-I receptor (IGF-IR), and PPARα gene mRNA expression and IGF-I secretion, but not (P > 0.05) IGFBP or PPARγ mRNA expression, in pig primary hepatocytes. These results indicate that SA improves growth performance by regulating IGF system gene expression and hormone secretion. 相似文献
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In sheep, perinatal maturation of the endocrine arm of the insulin-like growth factor (IGF) system is characterized by two developmental events. First, concentrations of circulating IGF-I increase rapidly after birth and become responsive to changes in nutrition and growth hormone (GH). Second, the liver initiates synthesis of a serum protein called the acidlabile subunit (ALS). The acid-labile subunit promotes the endocrine actions of IGF-I and -II by recruiting them to long-lived complexes of 150 kDa. In this study, we examined the effect of nutrition on hepatic expression of the ALS gene around the time of birth and later in life. Expression of genes encoding other components of the circulating IGF system was also measured. At d 130 of fetal life, fetuses suffering from chronic undernutrition caused by placental insufficiency had lower expression of the ALS and IGF-I genes than well-nourished fetuses, but they did not have any changes in the expression of the IGF-binding protein (IGFBP)-2 or IGFBP-3 genes. In early postnatal life, hepatic gene expression was analyzed between d 12 and 38 in lambs fed a milk replacer at levels sustaining weight gains of 150 or 337 g/d. The lower plane of nutrition decreased the expression of the ALS, IGF-I, and GH receptor genes and increased the expression of the IGFBP-2 gene; expression of the IGFBP-3 gene was not affected by nutrition at this stage of life. Finally, hepatic gene expression was measured in 3-mo-old lambs offered ad libitum levels of a balanced diet or of a diet limiting for both energy and protein. Although the rate of growth of the lambs fed the limiting diet was reduced by 38%, the only effect detected in hepatic gene expression was a ninefold increase in the abundance of IGFBP-2 mRNA. Overall, these results indicate that undernutrition during late fetal and early postnatal life delays hepatic expression of the ALS gene and final maturation of the endocrine IGF system. 相似文献
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S A Semevolos A J Nixon B D Brower-Toland 《American journal of veterinary research》2001,62(7):1088-1094
OBJECTIVE: To determine molecular changes in the expression of insulin-like growth factor-I (IGF-I) and transforming growth factor-beta1 (TGF-beta1) in horses with osteochondrosis, and to characterize expression of matrix aggrecan and collagen types I, II, and X in articular cartilage of affected joints. SAMPLE POPULATION: Articular cartilage from affected stifle or shoulder joints of 11 horses with naturally acquired osteochondrosis and corresponding joints of 11 clinically normal horses. PROCEDURE: Harvested specimens were snap frozen in liquid nitrogen, and total RNA was isolated. Specimens were fixed in 4% paraformaldehyde for histologic examinations. Expression of matrix molecules was assessed by analysis of northern blots and in situ hybridization, using equine-specific cDNA probes and riboprobes, respectively. Expression of IGF-I and TGF-beta1 was assessed by use of noncompetitive quantitative polymerase chain reaction, in situ hybridization, and immunohistochemical analysis. RESULTS: Cartilage obtained from osteochondrosis lesions had significantly greater expression of IGF-I, compared with normal cartilage. Expression of TGF-beta1 and collagen type I were higher, but not significantly so, in affected tissues. Expression of aggrecan or collagen types II and X did not differ between affected and clinically normal cartilage. CONCLUSIONS AND CLINICAL RELEVANCE: Increased expression of growth factors and collagen type I was found in cartilage from osteochondrosis lesions. However, this probably reflects a healing response to injured tissue rather than a primary alteration. Therefore, methods aimed at altering concentrations of growth factors in cartilage of growing horses would be unlikely to alter the incidence or progress of the disease. 相似文献
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Gene expression in sexually dimorphic muscles in sheep 总被引：4，自引：0，他引：4