Laboratory of Noncoding RNA, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China.
Protein Cell. 2012 Oct;3(10):755-61. doi: 10.1007/s13238-012-2936-2. Epub 2012 Aug 18.
Nematode sperm undergo a drastic physiological change during spermiogenesis (sperm activation). Unlike mammalian flagellated sperm, nematode sperm are amoeboid cells and their motility is driven by the dynamics of a cytoskeleton composed of major sperm protein (MSP) rather than actin found in other crawling cells. This review focuses on sperm from Caenorhabditis elegans and Ascaris suum to address the roles of external and internal factors that trigger sperm activation and power sperm motility. Nematode sperm can be activated in vitro by several factors, including Pronase and ionophores, and in vivo through the TRY-5 and SPE-8 pathways. Moreover, protease and protease inhibitors are crucial regulators of sperm maturation. MSP-based sperm motility involves a coupled process of protrusion and retraction, both of which have been reconstituted in vitro. Sperm motility is mediated by phosphorylation signals, as illustrated by identification of several key components (MPOP, MFPs and MPAK) in Ascaris and the characterization of GSP-3/4 in C. elegans.
线虫精子在精子发生（精子激活）过程中经历剧烈的生理变化。与哺乳动物鞭毛精子不同，线虫精子是变形虫细胞，其运动由由主要精子蛋白 (MSP) 组成的细胞骨架的动态驱动，而不是其他爬行细胞中的肌动蛋白。本综述重点介绍秀丽隐杆线虫和猪蛔虫的精子，以解决引发精子激活和驱动精子运动的外部和内部因素的作用。线虫精子可以通过几种因素在体外激活，包括蛋白酶和离子载体，并且可以通过 TRY-5 和 SPE-8 途径在体内激活。此外，蛋白酶和蛋白酶抑制剂是精子成熟的关键调节剂。基于 MSP 的精子运动涉及突起和缩回的偶联过程，这两个过程都已在体外重建。精子运动由磷酸化信号介导，这一点通过鉴定出猪蛔虫中的几个关键成分（MPOP、MFPs 和 MPAK）和秀丽隐杆线虫中的 GSP-3/4 得到了说明。
