Tulsiani Daulat R P, Abou-Haila Aïda
Department of Obstetrics and Gynecology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232, USA.
Bioessays. 2004 Mar;26(3):281-90. doi: 10.1002/bies.20003.
An important feature of male fertility is the physiological priming of spermatozoa by a multifaceted process collectively referred to as capacitation. The end point of this evasive process is the hyperactivated spermatozoa capable of binding to terminal sugar residues on the egg's extracellular coat, the zona pellucida (ZP), and undergoing acrosomal exocytosis (i.e., induction of the acrosome reaction). The hydrolytic action of acrosomal enzymes released at the site of zona binding, along with the enhanced thrust generated by the hyperactivated beat pattern of the bound spermatozoa, are important factors that regulate the penetration of ZP and fertilization of the egg. Despite many advances in identifying sperm components that promote capacitation, the mechanism underlying the calcium-triggered process remains elusive. The purpose of this review article is to focus on new advances that have enhanced our understanding of in vivo/in vitro capacitation, a prerequisite event resulting from a dramatic modification and reorganization of the sperm membrane molecules. Special emphasis has been laid on accumulating evidence suggesting potential similarities between the sperm capacitation and early phases of calcium-triggered membrane fusion (i.e., tethering and docking) during secretory and endocytotic pathways among eukaryotes.
男性生育能力的一个重要特征是精子通过一个被统称为获能的多方面过程进行生理预激活。这个难以捉摸的过程的终点是超活化的精子，它能够与卵子细胞外被膜即透明带（ZP）上的末端糖残基结合，并发生顶体胞吐作用（即诱导顶体反应）。在透明带结合部位释放的顶体酶的水解作用，以及结合的精子超活化搏动模式产生的增强推力，是调节透明带穿透和卵子受精的重要因素。尽管在鉴定促进获能的精子成分方面取得了许多进展，但钙触发过程的潜在机制仍然难以捉摸。这篇综述文章的目的是关注新进展，这些进展增进了我们对体内/体外获能的理解，获能是精子膜分子发生显著修饰和重组后产生的一个先决事件。特别强调了越来越多的证据，这些证据表明精子获能与真核生物分泌和内吞途径中钙触发的膜融合早期阶段（即拴系和对接）之间可能存在相似之处。
