Uchl1及其关联蛋白参与小鼠实验性隐睾中精母细胞凋亡(英文)

Uchl1 and its associated proteins were involved in spermatocyte apoptosis in mouse experimental cryptorchidism

以往研究显示Uchl1参与调节生理状况下小鼠精母细胞的凋亡。本文以小鼠实验性单侧隐睾为研究模型,以切除单侧睾丸和假手术作为对照,用苏木精-伊红(HE)染色和DNA末端标记(TUNEL)观察生精细胞的形态和凋亡情况;用免疫组化分析Uchl1及其相关蛋白Jab1和p27kip1在隐睾症的热应激反应导致精母细胞损失过程中的变化情况,并用亲和分析(pull-down)和免疫荧光共定位检测三种蛋白在精母细胞的关联性。结果显示,Jab1和p27kip1,与Uch1平行,在具凋亡形态的精母细胞中响应热应激而含量增加,而在多核巨细胞中无类似变化。Jab1可以与睾丸蛋白提取物中Uchl1结合,并与Uchl1和p27kip1特异性地在具凋亡形态的精母细胞中共定位。以上结果提示,Uchl1蛋白的积累参与隐睾中热应激诱导的生精细胞凋亡过程,但不影响接下来的多核巨细胞的形成,且Uchl1蛋白的作用机制涉及Jab1和p27kip1参与的一种新途径。

Uchl1 was found to be involved in spermatocyte apoptosis. The aim of the present study was to test whether Uchl1 and its associated proteins Jab1 and p27kip1 were involved in spermatogenic damages in response to heat-stress in cryptorchidism. Hematoxylin and eosin（HE） staining and DNA end labeling（TUNEL） were used to observe morphological and apoptotic characteristics of spermatogenic cells; Immunohistochemical analysis was used to detect changes of Uchl1 and its associated proteins Jab1 and p27kip1 in response to heat-stress from cryptorchidism leading to spermatocyte losses; And protein affinity analysis（pull-down） and immunofluorescence co-localization were used to verify the relevance among the three proteins in spermatocytes. The results showed that, Jab1 and p27kip1, in parallel to Uchl1, increased in spermatocytes of apoptotic appearances in response to heat-stress, but not in multinucleated giant cells; Jab1 bound to Uchl1 in testis protein extracts, and co-localized with Uchl1 and p27kip1 specifically in spermatocytes with apoptotic appearances. These results suggest that the accumulation of Uchl1 protein is involved in the heat-stress-induced spermatocyte apoptosis through a new pathway related with Jab1 and p27kip1, but not the formation of multinucleated giant cells.