牦牛和犏牛睾丸SAMD12基因的克隆测序及其mRNA水平比较

SAMD12是新近发现的SAM结构域家族成员.为进一步探究犏牛雄性不育的分子机制,实验从健康成年牦牛(n=10)和雄性不育犏牛(n=7)睾丸组织中提取总RNA,利用常规基因克隆技术,对牦牛SAMD12基因进行克隆测序,并采用实时荧光定量PCR技术,比较牦牛和犏牛睾丸中SAMD12基因mRNA水平.结果本实验克隆获得了牦牛SAMD12基因的3种变异体,分别命名为v715、v779和v852.v715与普通牛5号变异体完全对应;v779含SAM结构域但与普通牛序列存在一些差异,可能是SAMD12基因的新变异体类型;v852无结构域部分可能不表现活性.定量PCR结果显示:SAMD12基因在牦牛和犏牛睾丸中均有表达,但表达量差异不显著,推测其表达水平与犏牛雄性不育无直接关系.

Coloning and comparison of mRNA level of SAMD12 gene in the testes of yaks and cattle-yaks

SAMD12 is a member of the newly discovered SAM motif family. To explore the molecular mechanism of male sterility of cattle-yaks, total RNAs were extracted from the testes of healthy adult yaks (n=10) and sterile cattle-yaks (n=7), and SAMD12 gene was cloned and sequenced using routine gene cloning technique. The mRNA level of SAMD12 gene in the testes of yaks and cattle-yaks was assayed based on real-time quantative PCR. This study obtained 3 variants of yak SAMD12 gene, and named as v715, v779 and v852 respectively. v715 has the same sequence as bovine SAMD12 variant 5. v779 contains the SAM motif but shows some differences when compared with variants of bovine SAMD12 gene thus it is probably a new variant not reported in cattle. v852 does not have SAM motif and mostly shows no activity. Quantative PCR assay showed that SAMD12 gene was expressed in both yak and cattle-yak testes, however, the expression level was similar, suggesting that its abundance has no direct relationship with the male sterility of cattle-yaks.