The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, 1230 York Avenue, New York, New York 10065, USA.
J Endocrinol. 2013 Apr 15;217(2):R13-23. doi: 10.1530/JOE-12-0586. Print 2013 May.
During spermatogenesis, spermatids derived from meiosis simultaneously undergo extensive morphological transformation, to become highly specialized and metabolically quiescent cells, and transport across the seminiferous epithelium. Spermatids are also transported back-and-forth across the seminiferous epithelium during the epithelial cycle until they line up at the luminal edge of the tubule to prepare for spermiation at stage VIII of the cycle. Spermatid transport thus requires the intricate coordination of the cytoskeletons in Sertoli cells (SCs) as spermatids are nonmotile cells lacking the ultrastructures of lamellipodia and filopodia, as well as the organized components of the cytoskeletons. In the course of preparing this brief review, we were surprised to see that, except for some earlier eminent morphological studies, little is known about the regulation of the microtubule (MT) cytoskeleton and the coordination of MT with the actin-based cytoskeleton to regulate spermatid transport during the epithelia cycle, illustrating that this is a largely neglected area of research in the field. Herein, we summarize recent findings in the field regarding the significance of actin- and tubulin-based cytoskeletons in SCs that support spermatid transport; we also highlight specific areas of research that deserve attention in future studies.
在精子发生过程中，减数分裂产生的精母细胞同时经历广泛的形态转化，成为高度特化和代谢静止的细胞，并通过生精上皮运输。精母细胞也在生精上皮周期中来回运输，直到它们排列在管腔边缘，为周期的第八阶段的精子发生做准备。因此，精母细胞的运输需要 Sertoli 细胞 (SCs) 中的细胞骨架的精细协调，因为精母细胞是缺乏片状伪足和丝状伪足的超微结构以及细胞骨架的有组织成分的非运动细胞。在准备这篇简短综述的过程中，我们惊讶地发现，除了一些早期杰出的形态学研究外，对于微管 (MT) 细胞骨架的调节以及 MT 与肌动蛋白细胞骨架的协调如何在生精上皮周期中调节精母细胞运输知之甚少，这表明这是该领域一个被广泛忽视的研究领域。在此，我们总结了该领域关于支持精母细胞运输的 SCs 中肌动蛋白和微管细胞骨架的重要性的最新发现；我们还强调了未来研究中值得关注的特定研究领域。
