牦牛KDM7A表达谱分析及其在卵母细胞减数分裂进程中的表达

Analysis of KDM7A Expression Profile in Yak and Its Expression in the Process of Oocyte Meiosis

为探究组蛋白去甲基化酶7A(KDM7A)在牦牛生殖发育过程中的作用机制及表达模式,以牦牛作为研究对象,通过RT-PCR技术克隆获得牦牛KDM7A编码区序列,结合相关生物信息学分析软件分析KDM7A蛋白的结构和功能,利用实时荧光定量PCR(RT-PCR)获得KDM7A mRNA在牦牛卵巢、肾、胃、小肠、肌肉、心、子宫、脾、肺和肝中的表达水平,并分析该基因在卵母细胞成熟过程中的表达规律。结果显示,克隆出牦牛2704 bp的KDM7A基因,其中CDS区全长为2409 bp,共编码802个氨基酸。牦牛与其他物种中黄牛、野牛及山羊同源性较高;KDM7A在牦牛各组织中广谱表达,其在子宫中的相对表达量最高,显著高于除胃以外其他组织(P<0.05),而在肾脏和肌肉组织中相对表达量较低,显著低于其他组织(P<0.05);在卵母细胞减数分裂过程中,KDM7A基因具有时空动态表达特征,减数第二次分裂中期相对表达量显著高于减数第一次分裂中期和卵母细胞生发泡期(P<0.05)。综上表明,KDM7A在遗传进化过程中高度保守,在牦牛卵母细胞减数分裂进程中具有时序性表达模式,提示KDM7A参与卵母细胞的减数分裂进程,为深入探究牦牛KDM7A在生殖过程中的作用机制提供基础依据。

The objective of this research was to explore the expression pattern and molecular mechanism of histone demethylase 7 A(KDM7 A)in the reproductive development of yak.Yak was used as research object.The coding sequence of KDM7 A gene was cloned by RT-PCR.The protein structure and function of KDM7 A were analyzed by bioinformatics software,and the KDM7 A gene was detected by Real-time quantitative PCR(RT-qPCR)in theovary,kidney,stomach,small intestine,muscle,heart,uterus,spleen,lung and liver tissue.The expression pattern of KDM7 A mRNA was analyzed during the meiotic maturation of yak oocytes.The 2704 bp KDM7 A gene of the yak was cloned,and the CDS was 2409 bp in length and encoded a total of 802 amino acids.Compared with other species,the base sequence of yak KDM7 A was higher homology with cattle,bison and goat.Yak KDM7 A gene was widely expressed in various tissues,in which the uterus KDM7 A mRNA relative expression was the highest and significantly higher than other tissues except the stomach(P<0.05),while the relative expression of KDM7 A in kidney and muscle tissue was significantly lower than that in other tissues(P<0.05).There was spatiotemporal dynamic expression feature of the KDM7 A gene during the meiosis of oocytes.The expression level of KDM7 A in meiosis metaphaseⅡ(MⅡ)stage was significantly higher than that in meiosis metaphaseⅠ(MⅠ)and germinal vesicle(GV)stages of yak oocytes(P<0.05).In summary,this study suggested that KDM7 A gene was highly conserved in genetic evolution and involved in meiosis process of oocytes,which had a dynamic expression pattern during the reproductive development of yak.This study provided relevant basis for further exploring the action mechanism of yak KDM7 A in the process of reproduction.