内质网蛋白VAPA影响小鼠精子顶体生成的机制研究

Effect of endoplasmic reticulum associated protein VAPA on acrosome biogenesis in mice

目的探究内质网蛋白VAPA(Vesicle-associated membrane protein-associated protein A)对小鼠精子形成的影响。方法通过loxP-cre策略构建生精细胞特异的Vapa条件性基因敲除(Vapa CKO)小鼠模型;野生型和Vapa CKO成年雄性小鼠睾丸进行称重并统计分析;HE染色观察野生型和Vapa CKO成年雄性小鼠生精上皮形态;免疫荧光染色和透射电镜观察检测野生型和Vapa CKO成年雄性小鼠顶体的生成状况。结果生精细胞VAPA蛋白缺失时,小鼠睾丸重量明显减轻(P<0.0001);精子发生阻滞于圆形精子细胞,尤其是圆形精子细胞无法生成顶体。结论内质网蛋白VAPA参与小鼠的精子形成,并在顶体生成中发挥重要的作用。

Objective To investigate the effect of endoplasmic reticulum associated protein VAPA on spermiogenesis in mice.Methods A conditional knockout mouse model with specific Vapa gene deletion in germ cells(Vapa CKO)was constructed using the loxP-cre strategy.Testes collected from wild-type and Vapa CKO adult male mice were weighed for statistical analysis.HE staining was performed to analyze the histological morphology of the seminiferous epithelium.Immunofluorescence staining and transmission electron microscopy were used to determine acrosome biogenesis in wild-type and Vapa CKO adult male mice.Results The weight of testes from Vapa CKO adult male mice exhibited a significant decrease(P<0.0001).Specifically,spermatogenesis was arrested at round spermatids in Vapa CKO mice because round spermatids were unable to generate acrosome granule.Conclusion VAPA is involved in mouse spermiogenesis and plays an important role in acrosome biogenesis.