贵州黑山羊、贵州白山羊TFB1M基因第7外显子SNP研究

Study on SNP of TFB1M Exon7 in Guizhou Black Goat and Guizhou White Goat

目的:研究TFB1M基因编码区多态性,筛选出对山羊肉质有显著影响的SNPs位点,以期为山羊品种选种选育提供科学依据。方法:采用DNA池结合PCR直接测序技术分析TFB1M基因在贵州本地山羊的多态性,估算等位基因频率,利用在线软件分析TFB1M基因RNA二级结构及其蛋白二级、三级结构。结果:在TFB1M基因中筛选到2个SNPs:A76G和T221G,其中A76G为同义突变;T221G错义突变,导致编码的半胱氨酸(Cys)变为甘氨酸(Gly)。RNA二级结构最小自由能改变,贵州黑山羊RNA二级结构稳定性增强。贵州黑山羊β折叠链增加1%,α螺旋增加4%,混乱度也上升1%。β转角减少4,α螺旋增加6,自由卷曲减少3,延伸链增加1。结论:SNPs位点对TFB1M基因RNA二级结构及其蛋白结构均有影响。

Objective： In order to provide the basic information and scientific proof for better heredity selection of goat, the SNPs which has influenced on meat quality were screened in TFB1M gene＇s CDs. Method：The sequence of TFB1M gene of cattle which had high homo｜o- gy with goat was selected to design specific primers. The SNPs of Guizhou Black Goat and Guizhou White Goat in TFB1M were analyzed by direct sequencing of DNA pool. And the estimates of allele frequency and online predict software were analyzed TFB1M gene of RNA sec- ondary structure, protein secondary structure and protein tertiary structure. Result：Two SNPs （A76G and T221G） were found in TFBIM, which included one synonymous mutationand one missense mutations （T221 G, Cys→Gly） respectively. The minimum free energy of RNA secondary structure was changed because of the mutations. The stability of RNA secondary structurewas increasedin Guizhou black goat. Beta folded chain, alpha helixand chaotic degree were increased by 1%, 4% and 1%in Guizhou black goat respectively, Beta turnand random coilwere reduced by 4 and 3, alpha helix and extended strandwere increased by 6 and lrespectively. Conclusion：The result of the experiment validate that polymorphisms led to the changes of RNA secondary structure and protein structure.