Carbohydrates mediate sperm-ovum adhesion and triggering of the acrosome reaction

作     者：Daulat R.P 

作者机构：Thlsiani Department of Obstetrics & Gynecology and Cell Biology Vanderbilt University School of Medicine Room D-3243 MCN Nashville Tennessee 37232-2633 USA 

出 版 物：《Asian Journal of Andrology》 (亚洲男性学杂志（英文版）)

年 卷 期：2000年第2卷第2期

页      面：87-97页

核心收录：

学科分类：0710[理学-生物学] 07[理学] 071008[理学-发育生物学] 

基　　金：The work was supported in part by grants HD25869 and HD34041 from the National Institute of Child & Human Development 

主　　题：sperm capacitation sperm-ovum interaction acrosome reaction carbohydrates fertilization 

摘      要：The fertilization process is the net result of a complex sequence of events that collectively result in the fusion of theopposite gametes. The male gamete undergoes continuous morphological and biochemical modifications during spermdevelopment in the testis (spermatogenesis), maturation in the epididymis, and capacitation in the female reproductivetract. Only the capacitated spermatozoa are able to recognize and bind to the bioactive glycan residue(s) on the ovum sextracellular coat, the zona pellucida (ZP). Sperm-zona binding in the mouse and several other species is believed totake place in two stages. First, capacitated (acrosome-intact) spermatozoa loosely and reversibly adhere to the zona-in-tact ovum. In the second stage tight irreversible binding occurs. Both types of bindings are attributed to the presence ofglycan- binding proteins (receptors) on the sperm plasma membrane and their complementary bioactive glycan units(ligands) on the surface of the ZP. The carbohydrate-mediated adhesion event initiates a signal transduction cascade re-sulting in the exocytosis of acrosomal contents. This step is believed to be prerequisite which allows the hyperactivatedacrosome-reacted spermatozoa to penetrate the ZP and fertilize the ovum. This review focuses on the role of carbohy-drate residues in sperm-ovum interaction, and triggering of the acrosome reaction. I have attempted to discuss extensiveprogress that has been made to enhance our understanding of the well programmed multiple molecular events necessaryfor successful fertilization. This review will identify these events, and discuss the functional significance of carbohy-drates in these events.