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Leptin基因又称肥胖基因(obese gene),其编码蛋白称为瘦素,是由脂肪细胞分泌的内分泌激素,它作为多种功能调节轴的重要信息传递因子,调控动物机体能量代谢、神经和生殖活动。由于其对动物生长发育的重要作用,Leptin基因很早就受到畜牧研究者的重视。本文仅就牛Leptin基因的有关 相似文献
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徐琪 《上海畜牧兽医通讯》2003,(4):6-8
瘦蛋白 (Leptin)基因是由肥胖基因 (obesegene)编码、脂肪细胞分泌的一种激素 ,具有调节摄食行为、能量消耗、免疫反应和内分泌的功能。近几年来 ,Leptin在控制食物摄入量与肥胖 ,以及对生殖的影响成为众多学者共同关注的话题 ,在人及鼠类进行了大量研究 ,而在家畜方面才刚刚起步。本文主要从Leptin的生物特性、作用机理及其在生殖调控中的作用加以综述。1 Leptin生物学特性1.1 Leptin的化学性质Leptin是由 16 7个氨基酸残基组成 ,N端有 2 1个氨基酸残基构成的信号肽 ,表明Leptin是一种白脂肪细胞分泌蛋白 ,成熟蛋白为 14 6氨基酸残基… 相似文献
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《畜牧兽医学报》2015,(11)
自1998年首次报道从鸡的肝组织中克隆获得"鸡Leptin基因"以来,鸡Leptin基因序列的正确性以及Leptin在家禽中的存在性就一直备受争议。虽然家禽Leptin受体的存在被广泛证实,但对其功能的研究也由于内源性Leptin的缺乏而受到限制。随着后基因组学研究时代的到来,使得在更大范围、更深层次上探寻鸟类Leptin基因的存在与否成为可能。2014年,3个独立的实验室先后报道了部分野生鸟类Leptin基因的克隆和功能验证,将鸟类Leptin及其受体的研究又推向了新的高潮。本文综述了鸟类Leptin及其受体基因的结构特征、起源进化、组织分布及"生理功能"的最新研究进展。 相似文献
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Leptin(瘦蛋白)是肥胖基因(ob基因)表达的蛋白质产物,主要产生于脂肪组织,向大脑反馈能量储存的信息并激活下丘脑中枢,调节进食和能量的消耗,Leptin还可以通过直接或间接地影响了丘脑-垂体-性腺轴来调控动物的繁殖性能。本文从Leptin的生物学基础,作用机制及繁殖调控等方面予以综述。并指出了其在动物繁殖上的应用前景。 相似文献
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动物初情期的启动是其从幼年发育到获得繁殖能力的标志,初情期出现的迟早直接关系到性成熟和以后的繁殖性能.研究发现,很多基因及相关信号通路参与动物初情期启动的调控.目前,关于Leptin信号通路调控动物初情期的报道居多,而TRPC离子通道调控动物初情期的相关综述鲜见报道.因此,文章对Leptin/TRPC离子通道调控动物初... 相似文献
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绵羊CS-1基因的克隆及在凉山半细毛羊不同组织中的表达 总被引:1,自引:1,他引:0
旨在研究绵羊CS-1基因序列及其蛋白质的结构与功能以及其在不同组织中的表达情况,进而预测其与肉质性状的关联性.Calsarcins(Calcineurin-associated sarcomeric protein,CS)家族是一个与钙调神经磷酸酶(Calcineurin,CaN)相结合的肌纤维特异表达蛋白新成员,CS-1基因是与畜禽肉质性状密切相关的重要候选基因.本研究根据牛、人和鼠CS-1基因mRNA,应用比较基因组学技术成功克隆了绵羊CS-1基因全长cDNA,对序列及编码的氨基酸进行生物信息学分析.结果显示,该基因cDNA全长951 bp,完整的开放阅读框(ORF)为79~872 bp,编码264个氨基酸.氨基酸序列中存在3个保守结构域,蛋白质二级结构以无规卷曲和α-螺旋为主,富含疏水区,存在多个磷酸化位点和1个蛋白激酶C(Protein kinase C,PKC)的磷酸化位点.通过实时荧光定量RT-PCR技术分析CS-1基因在凉山半细毛羊部分组织中的表达情况.结果表明:CS-1基因主要在凉山半细毛羊的心脏和背肌中表达,15 d在心脏的表达量最高,极显著高于其它各组织(P<0.01);在心脏和背肌中,CS-1基因的表达量随着年龄的增长而减少,其中在60 d时心脏中的表达量最高.研究结果为绵羊的肉质性状改善提供科学依据. 相似文献
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饲料桑生理活性物质及其饲用价值 总被引:1,自引:0,他引:1
饲料桑蛋白质含量高、氨基酸种类丰富、纤维素含量低,富含多种生理活性物质,是一种优良的多年生饲料资源,对牛、羊、猪、兔、鸡、鱼等多种畜禽都具有很好的适口性。蛋禽日粮中添加桑饲料,可以显著改善蛋黄颜色,提高蛋黄磷脂和不饱和脂肪酸含量,增加蛋清浓稠蛋白含量,改善蛋的风味和品质。肉类畜禽日粮中添加桑饲料,可以显著改善肉品色泽,提高肌肉中肌苷酸和不饱和脂肪酸含量、减少胆固醇含量,降低肌肉滴水损失、延缓pH值下降及脂质氧化变质,提高肉品质量。牛、猪等大型肉类动物采食桑饲料后可减少皮下脂肪沉积,增加肌肉间脂肪含量,有效改善肉的品质风味。综述了饲料桑中主要生理活性物质的种类、含量、结构特征、生理功能及其在畜禽养殖中的饲用价值;从生产性能和改善品质方面分析总结了饲料桑在多种畜禽养殖中的应用效果;提出了减轻抗营养因子不利影响、改善栽培利用效果的技术措施;展望了饲料桑开发应用前景。 相似文献
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Biology of leptin in the pig 总被引:8,自引:0,他引:8
The recently discovered protein, leptin, which is secreted by fat cells in response to changes in body weight or energy, has been implicated in regulation of feed intake, energy expenditure and the neuroendocrine axis in rodents and humans. Leptin was first identified as the gene product found deficient in the obese ob/ob mouse. Administration of leptin to ob/ob mice led to improved reproduction as well as reduced feed intake and weight loss. The porcine leptin receptor has been cloned and is a member of the class 1 cytokine family of receptors. Leptin has been implicated in the regulation of immune function and the anorexia associated with disease. The leptin receptor is localized in the brain and pituitary of the pig. The leptin response to acute inflammation is uncoupled from anorexia and is differentially regulated among swine genotypes. In vitro studies demonstrated that the leptin gene is expressed by porcine preadipocytes and leptin gene expression is highly dependent on dexamethasone induced preadipocyte differentiation. Hormonally driven preadipocyte recruitment and subsequent fat cell size may regulate leptin gene expression in the pig. Expression of CCAAT-enhancer binding protein (C/EBP) mediates insulin dependent preadipocyte leptin gene expression during lipid accretion. In contrast, insulin independent leptin gene expression may be maintained by C/EBP auto-activation and phosphorylation/dephosphorylation. Adipogenic hormones may increase adipose tissue leptin gene expression in the fetus indirectly by inducing preadipocyte recruitment and subsequent differentiation. Central administration of leptin to pigs suppressed feed intake and stimulated growth hormone (GH) secretion. Serum leptin concentrations increased with age and estradiol-induced leptin mRNA expression in fat was age and weight dependent in prepuberal gilts. This occurred at the time of expected puberty in intact contemporaries and was associated with greater LH secretion. Further work demonstrated that leptin acts directly on pituitary cells to enhance LH and GH secretion, and brain tissue to stimulate gonadotropin releasing hormone secretion. Thus, development of nutritional schemes and (or) gene therapy to manipulate leptin secretion will lead to practical methods of controlling appetite, growth and reproduction in farm animals, thereby increasing efficiency of lean meat production. 相似文献
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Studies in the last two decades found that Leptin not only involves in the regulation of mammalian ingestion and energy homeostasis,but also serves as a metabolic signal regulating the mammalian reproduction by acting on the hypothalamic-pituitary-gonadal (HPG) axis,the placenta and the uterus.Leptin gene is one of the most important candidate genes for research on livestock's growth,development and meat quality,and also for research on prolificacy of livestock due to its key role in regulating the mammalian embryo implantation.Therefore,it is of important scientific significance and potential application value in studying functions and mechanisms of Leptin and its receptor gene.This paper is to dwell on how Leptin regulates mammalian breeding activities including the onset of puberty,development of reproductive organs and gonads,secretion of reproductive hormones,and embryo implantation,and also on how some reproduction activities influence the Leptin secretion in the body. 相似文献
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近二十年来的研究发现,瘦素除了参与哺乳动物摄食及能量代谢平衡过程的调节外,还作为一种代谢信号,通过作用于下丘脑—垂体—性腺轴、胎盘和子宫等来调控哺乳动物的繁殖过程。瘦素基因不仅是研究家畜生长发育、肉质等性状的重要候选基因,而且由于瘦素在调控哺乳动物胚胎附植过程中扮演的重要角色,它也是研究家畜多胎性状的重要候选基因之一。研究瘦素及其受体基因的功能及作用机制具有重要的科学意义和潜在的应用价值。文章主要就瘦素对哺乳动物初情期的启动、生殖器官及性腺的发育、生殖激素的分泌、胚胎附植等繁殖活动的调控,以及性别与年龄、妊娠与哺乳、繁殖节律等对瘦素分泌的影响等方面进行综述。 相似文献
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