荷斯坦奶牛FGFR2基因组织表达及生物信息学分析

Differential expression and bioinformatics analysis of FGFR2 gene in Holstein cows

探究前期GWAS筛选出的与荷斯坦奶牛产奶性状相关的成纤维生长因子受体2(Fibroblast growth factor receptor 2,FGFR2)基因不同组织表达量以及荷斯坦奶牛FGFR2基因生物学功能,为后续验证FGFR2基因对于荷斯坦奶牛产奶相关性状调控机制提供基础。采用RT-PCR方法克隆荷斯坦奶牛FGFR2基因CDS区;再利用实时荧光定量PCR技术检测该基因在荷斯坦奶牛不同组织中表达量;最后对其作序列分析及蛋白结构和功能预测等生物信息学分析。实时荧光定量PCR结果显示荷斯坦奶牛乳腺组织FGFR2相对表达量最高,极显著高于肝脏、卵巢、子宫和心脏,与肾脏组织mRNA表达量差异不显著。FGFR2基因系统进化树结果显示,荷斯坦奶牛与黄牛亲缘性最近,其次为野猪。荷斯坦奶牛FGFR2基因编码区长2372 bp,编码790个氨基酸,蛋白分子式为C3923H6159N1067O1190S44,相对分子质量为12383,半衰期为30 h,脂肪指数为78.71,为亲水蛋白;FGFR2蛋白存在一个跨膜结构,无信号肽为非经典分泌蛋白;有5个保守结构域;二级结构分析表明,该蛋白中α-螺旋占23.80%,β-转角占4.18%,无规则卷曲占51.27%,延伸链占20.76%,为后期荷斯坦奶牛FGFR2基因在奶牛产奶相关性状调控机制研究提供理论依据。

The purpose of this study was to screen out the FGFR2 gene related to the milk production traits of Holstein cows by GWAS in the early stage,research of the FGFR2 gene expression in different tissues and its biological function,so as to provide the basis for further verifying of the regulation mechanism of FGFR2 gene on milk production related traits of Holstein cows.The CDS region of FGFR2 gene of Holstein cows was cloned by RT-PCR,and the expression of FGFR2 gene in different tissues of Holstein cows was detected by real-time fluorescent quantitative PCR.Finally,the sequence analysis,protein structure and function prediction and other bioinformatics analysis were carried out.The results of real-time fluorescence quantitative PCR showed that the relative expression of FGFR2 in the mammary tissues of Holstein cows was the highest,and it was extremely significantly higher than that in the liver,ovary,uterus and heart,but there was no significant difference in mRNA expression between mammary and kidney.The phylogenetic tree of FGFR2 gene showed that Holstein cows had the closest relationship with Bos taurus,followed by Sus scrofa.The coding region of FGFR2 gene in Holstein cow was 2372 bp,encoding 790 amino acids.The protein molecular formula was C3923H6159N1067O1190S44,the relative molecular weight was 12383,the half-life was 30 h,the fat index was78.71,it was a hydrophilic protein;FGFR2 protein had a transmembrane structure,which was non classical secretory protein without signal peptide;there were five conserved domains;the secondary structure analysis showed that the protein containedα-helix accounted for 23.80%,β-turn accounted for 4.18%,irregular curl accounted for 51.27%,and extended chain accounted for 20.76%.It provided basic data for the study of regulation mechanism of FGFR2 gene in milk production related traits of later Holstein cows.