Wang Liying, Zhang Ruidan, Wu Bingbing, Yu Yang, Li Wei, Li Shiguo, Liu Chao
Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou 510623, China.
State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Stem Cell and Regenerative Medicine Innovation Institute, Chinese Academy of Sciences, Beijing 100101, China.
Fundam Res. 2022 Oct 25;4(6):1557-1567. doi: 10.1016/j.fmre.2022.10.006. eCollection 2024 Nov.
Spermiation is the process that releases mature spermatids from Sertoli cells into the lumen of the seminiferous tubule. Tubulobulbar complexes (TBCs) are elaborate cytoskeleton-related structures that are indispensable for spermiation. Despite well-defined ultrastructural events, the molecular regulation of TBCs during spermiation remains largely unknown. Here, we show that autophagy is active in TBC regions, and impaired autophagy in Sertoli cells affects spermiation. Further studies demonstrated that many TBC components bound to LC3 and could be selectively degraded through the autophagy-lysosome pathway. Perturbed autophagy impaired the degradation of some TBC components in Sertoli cells, such as VCL and CTTN, and led to the accumulation of TBC components surrounding the spermatid head, which may be associated with the sperm-releasing defect. Together, our results reveal that autophagy is essential for the TBC components degradation in mouse Sertoli cells and define a functional role of autophagy during spermiation.
精子释放是指成熟精子细胞从支持细胞释放到生精小管管腔的过程。管球复合体（TBCs）是与细胞骨架相关的精细结构，对精子释放至关重要。尽管超微结构事件已明确，但精子释放过程中TBCs的分子调控仍 largely未知。在此，我们表明自噬在TBC区域活跃，支持细胞中自噬受损会影响精子释放。进一步研究表明，许多TBC成分与LC3结合，并可通过自噬-溶酶体途径被选择性降解。自噬紊乱会损害支持细胞中某些TBC成分（如VCL和CTTN）的降解，并导致精子细胞头部周围TBC成分的积累，这可能与精子释放缺陷有关。总之，我们的结果表明自噬对小鼠支持细胞中TBC成分的降解至关重要，并确定了自噬在精子释放过程中的功能作用。
