The Sperm Laboratory, Institute of Cell Biology and Genetics, College of Life Sciences, Zhejiang University, Hangzhou 310058, China.
Gene. 2012 Oct 15;508(1):78-84. doi: 10.1016/j.gene.2012.07.035. Epub 2012 Jul 27.
Myosin Va is an F-actin dependent molecular motor with multiple functions that are essential for acrosome formation in mouse spermiogenesis. The spermatozoon of the crab has a complicated acrosome surrounded by a cup-shaped nucleus. In the present study, the myosin Va cDNA was cloned from the testis of the Chinese mitten crab Eriocheir sinensis using degenerate PCR and rapid amplification of cDNA ends (RACE). The myosin Va cDNA consists of a 125 bp 5'-untranslated region (5' UTR), a 5331 bp open reading frame (ORF) and a 590 bp 3' UTR. The putative myosin Va protein contains the head domain, neck domain and tail domain. Multiple alignment and phylogenetic tree showed that E. sinensis myosin Va is more closely related to the vertebrate myosin Va than to the invertebrate myosin V. E. sinensis myosin Va was expressed in various tissues. In situ hybridization demonstrated that myosin Va mRNA is located in the entire process of spermatogenesis. Quantitative real-time PCR indicated that the expression level at the mitotic and meiotic phases is higher than the spermiogenesis phase. Taken together, our work suggests that myosin Va may function in E. sinensis spermatogenesis.
肌球蛋白 Va 是一种依赖于 F-肌动蛋白的分子马达，具有多种功能，对精子发生过程中的顶体形成至关重要。蟹类的精子具有复杂的顶体，周围环绕着杯状核。在本研究中，使用简并 PCR 和快速扩增 cDNA 末端 (RACE) 从中华绒螯蟹 (Eriocheir sinensis) 的睾丸中克隆了肌球蛋白 Va cDNA。肌球蛋白 Va cDNA 包含 125bp 的 5'非翻译区 (5'UTR)、5331bp 的开放阅读框 (ORF) 和 590bp 的 3'UTR。推测的肌球蛋白 Va 蛋白包含头部结构域、颈部结构域和尾部结构域。多重比对和系统发育树显示，中华绒螯蟹肌球蛋白 Va 与脊椎动物肌球蛋白 Va 的亲缘关系比与无脊椎动物肌球蛋白 V 更密切。中华绒螯蟹肌球蛋白 Va 在各种组织中均有表达。原位杂交显示肌球蛋白 Va mRNA 位于整个精子发生过程中。实时定量 PCR 表明，有丝分裂和减数分裂阶段的表达水平高于精子发生阶段。综上所述，我们的工作表明肌球蛋白 Va 可能在中华绒螯蟹的精子发生中发挥作用。
