牦牛瘦素受体基因(LEPR)多态性分析  

Polymorphism of Leptin Receptor Gene(LEPR) in Yak(Bos grunniens)

作　　者：闫伟[1] 罗玉柱[1] 杨勤 成述儒[1] 胡江[1] 

机构地区：[1]甘肃省草食动物生物技术重点实验室/甘肃农业大学动物科学技术学院,兰州730070 [2]甘南州畜牧兽医科学研究所,合作747000

出　　处：《农业生物技术学报》2011年第2期323-329,共7页Journal of Agricultural Biotechnology

基　　金：国家科技支撑计划课题(No.2007BAD52B05和No.2009BAC53B06);甘肃省重点实验室建设计划项目(No.085RTSA004);甘肃省发改委项目共同资助

摘　　要：瘦素受体(LEPR)是瘦素(leptin)发挥作用的重要中介物。LEPR基因突变与人的肥胖,以及普通牛、猪等动物的脂肪沉积相关。本研究根据GenBank中普通牛(Bos tauras)LEPR基因序列设计3对引物,采用PCR-SSCP方法检测天祝白牦牛、甘南牦牛和青海牦牛(Bos grunniens)LEPR基因第4、5及8外显子及其相邻区域多态性。结果表明,牦牛LEPR基因第4外显子和第8外显子及其相邻区域分别存在多态性。对应普通牛LEPR基因序列,3类群牦牛该基因第4外显子及相邻区域检测到5处单碱基突变并形成2种等位基因A和B,第4外显子存在2处错义突变;该区域A为优势等位基因,PIC<0.25为低度多态。3类群牦牛LEPR基因第8外显子及其相邻区域发现5处SNPs,其中第8外显子存在3处错义突变;等位基因在牦牛群体间分布不均衡,除天祝白牦牛发现6种等位基因A-F外,其余两类群牦牛仅发现3种等位基因A-C;3类群牦牛中A均为优势等位基因,该位点PIC>0.25,为中、高度多态且显著偏离Hardy-Weinberg平衡状态(P<0.05)。3类群牦牛LEPR基因第5外显子及相邻区域未发现多态性,但相对于普通牛该基因序列,在第4、5内含子区存在3处SNPs。LEPR基因第8外显子编码识别和结合相应配体的C2区,牦牛LEPR基因存在较丰富的多态性,可作为其调控性状的潜在分子标记位点。Leptin receptor（LEPR） plays a pivotal role in regulating leptin function as leptin binding protein.Variation in the LERP gene has been associated with obesity in human and fat deposition in cattle,swine and other animals.In this study,three pairs of primers were designed respectively referring to bovine（Bos tauras） LERP exon 4,exon 5 and exon 8 as well as their contiguous parts sequence in GenBank,so as to investigate the variations in corresponding part of LERP gene in Tianzhu white yak,Gannan yak and Qinghai yak（Bos grunniens） by polymerase chain reaction-single strand conformational polymorphism（PCR-SSCP） analysis.The polymorphisms were observed at LERP exon 4 and exon 8 as well as their contiguous parts in yak.Two allelic variations containing five single nucleotide polymorphisms（SNPs） were observed including two missense mutations at LERP exon 4 and contiguous parts in three yak populations.Allele A was the most common allele and the polymorphism was low with PIC less than 0.25 at this region of LEPR gene in yak.Five SNPs including three missenses mutations were checked at LERP exon 8 and contiguous parts in yak,but alleles distributed disproportionably among three yak populations,such as alleles A→F observed in Tianzhu white yak,but alleles A→C in Gannan yak and Qinghai yak.Allele A was the most common allele,and that allelic and genotype frequency were significantly deviated from Hardy-Weinberg balanced（P0.05）.The polymorphism was higher or moderate with PIC more than 0.25 at LERP exon 8 in three yak populations.No polymorphism was found at LERP exon 5 and contiguous parts,but three SNPs were observed at intron 4 and intron 5 relative to bovine LERP gene sequence.Exon 8 for LEPR gene codes the amino acids consisting of C2 domain of LEPR where amino acids recognizes and binds ligand,for LEPR gene with much polymorphism,exon 8 would become a potential locus for genetic markers,in which it may be possible for traits regulation.

关 键 词：牦牛 瘦素受体基因(LEPR) PCR-SSCP SNPS 

分 类 号：S813.1[农业科学—畜牧学]