奶牛HSP70 基因表达及其连锁微卫星标记与耐热性状的相关性  

Analysis of HSP70 mRNA level and association between linked microsatellite loci and heat tolerance traits in dairy cows

作　　者：刘延鑫[1] 李大齐[1] 崔群维[1] 史红霞[1] 王根林[1] 

机构地区：[1]南京农业大学动物科技学院。南京210095

出　　处：《遗传》2010年第9期935-941,共7页Hereditas（Beijing)

基　　金：国家科技支撑计划项目(编号:2006BAD04A01,2006BAD04A12);江苏省科技支撑计划项目(编号:BE2008306-2)资助

摘　　要：为了研究奶牛HSP70基因的mRNA表达规律和其紧密连锁的3个微卫星标记与耐热性状的相关性,文中在日平均温湿度指数(THI)为86.2(高温期)、70.9(临界高温期)和56.8(适温期)时分别采集10头处于同一泌乳阶段的同龄健康奶牛的尾静脉血,采用实时荧光定量RT-PCR技术分析不同条件下奶牛HSP70基因在外周血淋巴细胞的mRNA表达水平。结果表明:随THI升高,HSP70mRNA表达量呈上升趋势,高温期奶牛的外周血淋巴细胞HSP70mRNA表达丰度极显著高于临界高温期和适温期(P<0.01),且与奶牛的耐热指标具有一定的遗传相关,表明HSP70基因可以作为奶牛热应激反应的候选基因。选取23号染色体上与HSP70紧密连锁的3个微卫星标记BMS468、BM1258和BM1815,用非变性聚丙烯酰胺凝胶电泳分析其在160头荷斯坦奶牛的遗传变异情况,利用最小二乘法拟合线性模型初步探索了这3个微卫星座位与奶牛耐热指标的关系。相关分析表明:耐热系数、红细胞钾含量及高温期日产奶量下降率的最有利基因型在BMS468基因座和BM1815基因座上,分别为134bp/128bp(P<0.05)和186bp/148bp(P<0.05);BM1258基因座上,最有利基因型101bp/99bp的高温期日产奶量下降率最低(P<0.05)。The objective of this study was to investigate the variation of HSP70 mRNA level in dairy cows and relationships of its closely linked microsatellite loci with heat tolerance traits. Blood samples were collected from ten healthy Holstein cows with the same age and milking stage at different temperatures-humid-index （THI） （86.2, high temperature; 70.9, critical high temperature, and 56.8, optimum temperature）. The mRNA levels of HSP70 of lymphocytes in peripheral blood were analyzed using real-time RT-PCR. The mRNA level of HSP70 was increased with the THI; the mRNA level of HSP70 at high temperature was higher than others （P〈0.01）. This indicated that the bovine HSP70 gene may act as a potential can-didate gene for response to heat shock. Genetic variation of three microsatellite loci BMS468, BM1258, and BM1815, which were closely linked to HSP70 gene on chromosome 23, was analyzed in 160 Holstein cows with non-denaturing poly-acrylamide gel electrophoresis. The association between these microsatellite loci and heat tolerance traits were analyzed by least square linear model. The results showed that 134 bp/128 bp at BMS468 and 186 bp/148 bp at BM1815 were the most favorable genotypes for HTC, red cell potassium, and decrement rate of milk yield in high temperature （P〈0.05）; 101 bp/99 bp at BM1258 was the most favorable genotype for decrement rate of milk yield in high temperature （P〈0.05）.

关 键 词：奶牛 HSP70 耐热性 微卫星标记 实时荧光定量RT-PCR 

分 类 号：S823[农业科学—畜牧学]