牦牛和雄性不育杂交后代睾丸组织差异表达核蛋白的双向电泳分析

Comparative Analysis on Differential Expression of Testicular Nucleoproteins between Yak and Sterile Hybrid by Two-dimensional Electrophoresis

研究比较牦牛(Bos grunniens)和犏牛睾丸核蛋白的表达差异,以探索公犏牛不育的分子机制。提取牦牛(n=4)和犏牛(n=4)睾丸的核蛋白,采用双向电泳分离后,对差异表达蛋白质点进行质谱鉴定。通过分辨率高、重复性好的睾丸组织核蛋白双向电泳图谱,检测出在牦牛和犏牛睾丸存在2倍及以上差异表达的蛋白点15个,通过MALDI-TOF-TOF质谱鉴定得到13种差异表达蛋白,大多数为核蛋白,在犏牛睾丸中表达显著下降,另外还包括4种核不均一蛋白(hnRNPs)。这些蛋白质参与精子发生、前体RNA加工和选择性剪接、基因表达调控等过程,其表达的改变可能与犏牛精子发生障碍有关。

The purpose of this study was to compare differentially expressed nucleoproteins in the testes of yak（Bos grunniens）and sterile hybrid,in order to explore the molecular mechanism of infertility of male cattle-yak.Total nucleoproteins were extracted from the testes of yaks（n=4）and cattle-yaks（n=4）,and separated by two-dimensional electrophoresis followed by identification of the differentially expressed nucleoproteins with mass spectrometry.The well-resolved,reproducible twodimensional electrophoresis gels of yak and cattle-yak testicular nucleoproteins were obtained.Through the analysis of the spots with two fold expression difference,a total of 15 differentially expressed protein spots were detected and 13 differential proteins were further identified by MALDITOF-TOF mass.Most of the identified proteins were nucleoproteins and showed significantly decreased expression in the testis of cattle-yak,including four kinds of heterogeneous nuclear protein（hnRNPs）.The changes in the expression of these nucleoproteins,which are involved in spermatogenesis,the hnRNA processing and alternative splicing,the process of gene expression and regulation,might be associated with the failure of spermatogenesis in cattle-yak.