Ⅳ型胶原蛋白NC1片段在精子发生及血睾屏障中作用的研究进展

Advances in the effect of NC1 domain of typeⅣcollagen on spermatogenesis and blood-testis barrier

在哺乳动物睾丸中,位于生精上皮基底膜附近的血睾屏障(blood-testis barrier,BTB)对精子发生至关重要。BTB由相邻的支持细胞(Sertoli细胞)连接而成,将生精上皮分为靠近基底膜的“基底室”和靠近生精小管管腔的“近腔室”,为精子发生提供了免疫屏障。Ⅳ型胶原蛋白是基底膜的重要组成成分,啮齿类动物的睾丸中Ⅳ型胶原蛋白主要是由3条α3链组成的三螺旋结构。大鼠睾丸的Ⅳ型胶原蛋白α3链C端可以水解成大小为28 ku的蛋白片段,称为C端非胶原结构域(noncollagenous domain-peptide,NC1片段)。NC1片段作为一种基底膜源性多肽在参与精子发生与维系BTB功能方面发挥了重要作用。本文通过分析、总结近期研究结果,概述Ⅳ型胶原蛋白NC1片段在睾丸中的作用及其机制,尤其是其在精子发生与BTB中作用的研究进展。

In mammalian testis,the blood-testis barrier(BTB),located near the basement membrane ofseminiferous epithelium,is essential forspermatogenesis.BTB is formed by the joining of adjacent Sertoli cells and divides theseminiferous epithelium into basal compartment near the basement membrane and apical compartment near the lumen ofspermatogenic tubules.The barrier provides an immune defense mechanism forspermatogenesis.TypeⅣcollagen is an important component of basement membrane.In rodent testis,typeⅣcollagen is mainly composed of threeα3 chains in a triple helixstructure.The C-terminal noncollagenous domain(NC1 domain)of typeⅣcollagenα3 chain of rat testis can be hydrolyzed into a 28 ku protein fragment called NC1 domain.NC1 domain as a basement membrane peptide is involved inspermatogenesis and'sustains BTB function.This article reviews recent research results in order to identify the role of typeⅣcollagen NC1 domain in testis and underlying mechanisms,mainly focuses onspermatogenesis and BTB.