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Leptin是动物肥胖基因的表达产物,有人称之为肥胖蛋白,具有明显降低机体肥胖程度的功能,因此也有人称之为瘦蛋白。最早发现这种新蛋白的是美国洛克菲勒大学的Zhang,YR等人(1994)发现小白鼠的能量平衡受到某种物质的调控,该物质主要是由肥胖基因编码的。他们克隆了几种类型的小白鼠肥胖基因并进行测序,发现mRNA由4.5kb组成,其中一段编码167个氨基酸的序列相对保守。进而他们又从小白鼠白脂肪组织eDNA文库中克隆出了肥胖基因eDNA,测序发现5’端由97个碱基组成,随后是编码167个氨基酸的保守序列,3’端则由3700多个碱基组成的非翻译序列。这段保守序列编码产物就是高效调控能量平衡的物质,命名为Leptin。最近猪、鸡的Leptin基因也得到了克隆,并获得了表达产物。 相似文献
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猪肥胖(OB)基因的研究进展 总被引:1,自引:0,他引:1
OB基因是近年刚被克隆的新基因,其产物Leptin是反映体内脂肪含量和调节体重的重要信号因子。克隆和分析研究OB基因,对猪的育种和提高瘦肉率有重要意义。本文综述了最近国内外猪OB基因的研究进展,主要包括OB基因cDNA的克隆和分析、OB基因产物Leptin的测序、表达及生物学功能、OB-R基因的研究现状等,对OB基因的研究前景进行了展望。 相似文献
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肥胖基因(obese gene,ob)是近年来克隆的一种基因.畜禽ob基因研究工作目前主要集中在基因克隆与定位、生理机能、多态性分析以及与生产性状之间的关系等方面.ob基因编码的瘦蛋白(Leptin)是由白色脂肪细胞分泌的一种蛋白质,具有降低动物采食量、维持动物能量平衡、调节动物的繁殖机能和提高动物的免疫功能等作用.近些年来,国内外很多科研单位对ob基因的研究投入了大量的工作,进行了较深入的研究.现就ob基因研究进展及其应用前景作一综述. 相似文献
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瘦素的生物学功能研究进展 总被引:1,自引:0,他引:1
瘦素(leptin),亦称瘦蛋白、抗肥胖因子、苗条素,是主要由脂肪细胞分泌的一种激素样蛋白质。瘦素具有参与采食调控、能量代谢、生殖发育、骨代谢、造血和免疫等过程的生物学功能。1994年zhang Y等首次利用基因定位克隆技术克隆得到小鼠的肥胖基因(obesegene,ob基因), 相似文献
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鸭肥胖基因的分子克隆、序列分析及原核表达 总被引:5,自引:0,他引:5
根据人、小鼠、猪等动物的肥胖基因编码区序列的保守性设计1对引物,利用RT-PCR技术扩增出鸭肥胖基因的cDNA编码序列,将PCR产物插入pGEM-T载体,经:PCR和双酶切鉴定正确后进行序列测定,分析表明该cDNA序列由438个核苷酸组成,编码146个氨基酸组成的多肽,鸭与人、猪、小鼠、大鼠的核苷酸相似性分别为83%、84%、98%、94%;氨基酸的相似性分别为86%、83%、99%、96%。为了研究鸭肥胖基因体外表达的特点,构建了原核表达载体pET-28a-Ya,在大肠杆菌中进行了诱导表达。结果表明,鸭肥胖基因在大肠杆菌中进行了高效特异性融合表达,融合蛋白分子量约为20ku,其中16ku为鸭肥胖基因表达的蛋白质,经薄层扫描分析,目的蛋白约占菌体总蛋白的30%。鸭肥胖基因的克隆和表达研究,为进一步研究鸭leptin的功能与应用奠定了基础。 相似文献
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The aim of the current research was to investigate the possible occurrence of a single nucleotide polymorphism (SNP) in exon 2 of the equine leptin gene in obese mares determined to be hyperleptinemic. Three experiments were conducted: one to determine the prevalence of hyperleptinemic horses in the resident herd; another to complete the sequencing of exon 2 and flanking introns of the equine leptin gene, which had been partially sequenced by others; and a third to compare the exon 2 sequences of obese, hyperleptinemic mares with those of obese mares not displaying hyperleptinemia. In experiment 1, jugular blood was collected from 31 mares, and they were categorized by age, body condition score (BCS), and average plasma leptin concentrations. Mean BCS was correlated (P < .001) with leptin concentrations; age was not. Five obese, hyperleptinemic and five obese, nonhyperleptinemic mares were selected to study the possibility of polymorphism in exon 2. First, in experiment 2, forward and reverse primers were designed from the Bos taurus leptin gene (GenBank Accession # U50365) to identify and subsequently clone the equine leptin gene to provide material for sequencing. The multiple copies of genomic DNA were then used for sequencing of exon 2 and the flanking introns. Comparative genomics was used to further identify and characterize regulatory elements in the 5' and 3' flanking regions of the leptin gene. In experiment 3, DNA from the five mares of each type (previously selected in experiment 1) was extracted, and exon 2 was sequenced and analyzed for possible SNP. The sequences of exon 2 for the 10 mares were identical; thus, no polymorphism was present. It was concluded that approximately one third of obese, pasture-maintained mares and geldings in the resident herd display hyperleptinemia relative to other horses of similar body condition, but this condition was not associated with the occurrence of SNP in exon 2 of the leptin gene. 相似文献
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Leptin(瘦素)是肥胖基因ob基因的表达产物,由脂肪细胞分泌,与下丘脑Leptin受体结合,可抑制食欲中枢,减少进食量,并通过兴奋交感神经系统,促进脂肪分解,增加产热,从而发挥降低体重,提高瘦肉率的功能。对Leptin的生物学功能及其对脂肪沉积的调控作用进行综述,以期为营养上调控畜禽肉品质,以及生产优质畜禽产品提供理论依据和科研基础。 相似文献
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试验选用内江猪、荣昌猪和长白猪初产母猪,研究肥胖基因mRNA在不同品种间的表达差异及其与繁殖性能间的关系。从发情第1天开始,连续3d测定血清促卵泡素(FSH)、促黄体素(LH)和瘦素(Leptin)水平,并于第3天各屠宰5头母猪以测定皮下脂肪组织obmRNA表达丰度,同时对其他母猪进行繁殖性能观测。结果表明:内江猪和荣昌猪皮下脂肪组织obmRNA表达丰度及血清Leptin浓度显著高于长白猪种。obmRNA表达丰度与Leptin浓度高度正相关,且两者与初产母猪的血清FSH、LH和总产仔数呈正相关,而与初生个体重呈负相关。 相似文献
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Park ES Seong JK Yi SJ Kim JS Lee HS Lee IS Yoon YS 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2005,67(7):639-646
This study was carried out to investigate the changes of orexin-A (OXA) and neuropeptide Y (NPY) expression in the hypothalamus of the obese and lean Zucker Diabetic Fatty (ZDF) rats which have a missense mutation in the leptin receptor gene. The mean body weights (MBW) between the obese and lean ZDF rats were significantly different at 28 and 70 postnatal days. However, at 14 postnatal day, there was no significant difference in the MBW between the obese and lean ZDF rats in both male and female. The OXA immunoreactivities were not significantly different between the obese and lean ZDF rats in both sexes at 14, 28, and 70 postnatal days, respectively. The NPY immunoreactivity was higher in the obese than in the lean ZDF rats in both male and female at 28 and 70 postnatal days, whereas there was no significant difference between the obese and lean ZDF rats at 14 postnatal day. These results indicate that both OXA and NPY might halt their roles for food intake in the obese phenotype of the male and female ZDF rats in the preweaning period of 14 postnatal day, whereas NPY might play a main role in the obesity of these rats in the weaning period of 28 and 70 postnatal days. 相似文献
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The brain-pituitary-adipocyte axis: role of leptin in modulating neuroendocrine function. 总被引:6,自引:0,他引:6
C R Barb 《Journal of animal science》1999,77(5):1249-1257
The recently discovered protein leptin has a molecular mass of 16 kDa, consists of 146 amino acids, and is synthesized and secreted by adipose tissue. Leptin affects feed intake, the neuroendocrine-axis, and immunological processes. The protein was first identified as the gene product that is deficient in the obese ob/ob mouse. Leptin serves as a circulating signal of nutritional status and plays a pivotal role in regulation of body weight, energy expenditure, growth, and reproduction. 相似文献
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H J Mersmann 《Journal of animal science》1985,60(1):131-135
In vitro lipolytic rate was determined in adipose tissue from genetically obese and lean pigs. There were about 20 pigs/genetic strain at 25 and 80 kg and 10 pigs/strain at 50 kg body weight. When expressed on a cellular basis, the in vitro adipose tissue basal (no exogenous hormone) lipolytic rate was similar in obese and lean pigs at 25 and 50 kg body weight. At 80 kg body weight the basal rate was greater in obese than in lean pigs. The in vitro adipose tissue epinephrine-stimulated lipolytic rate expressed on a cell basis was greater at 25 kg, was similar at 50 kg body weight and tended (P less than or equal to .1) to be greater at 80 kg in obese compared with lean pigs. The in vitro sensitivity of lipolysis to epinephrine was slightly greater in lean compared with obese pigs. The data obtained in vitro indicate that obese pigs do not have low adipose tissue lipolytic rates compared with lean pigs. Consequently, adipose tissue lipolysis does not appear to be a major metabolic factor leading to the excessive fat accretion in these obese pigs. 相似文献