Tulsiani D R, Abou-Haila A
Department of Obstetrics & Gynecology, Vanderbilt School of Medicine, Nashville, Tennessee 37232-2633, USA.
Zygote. 2001 Feb;9(1):51-69. doi: 10.1017/s096719940100106x.
Fertilisation is a highly programmed process by which two radically different cells, sperm and egg, unite to form a zygote, a cell with somatic chromosome numbers. Development of the zygote begins immediately after sperm and egg haploid pronuclei come together, pooling their chromosomes to form a single diploid nucleus with the parental genes. Mammalian fertilisation is the net result of a complex set of molecular events which allow the capacitated spermatozoa to recognise and bind to the egg's extracellular coat, the zona pellucida (ZP), undergo the acrosome reaction, and fuse with the egg plasma membrane. Sperm-zona (egg) interaction leading to fertilisation is a species-specific carbohydrate-mediated event which depends on glycan-recognising proteins (glycosyltransferases/glycosidases/lectin-like molecules) on sperm plasma membrane (receptors) and their complementary glycan units (ligands) on ZP. The receptor-ligand interaction event initiates a signal transduction pathway resulting in the exocytosis of acrosomal contents. The hydrolytic action of the sperm glycohydrolases and proteases released at the site of sperm-egg interaction, along with the enhanced thrust generated by the hyperactivated beat pattern of the bound spermatozoon, are important factors regulating the penetration of egg investments. This review focuses on sperm molecules believed to be important for the interaction with the female genital tract, passage through cumulus oophorus and attachment to ZP, induction of the acrosome reaction, secondary binding events, and passage through the ZP. An understanding of the expression and modifications of molecules thought to be important in multiple events leading to fertilisation will allow new strategies to block these modifications and alter sperm function.
受精是一个高度程序化的过程，在此过程中，精子和卵子这两种截然不同的细胞结合形成合子，即具有体细胞染色体数目的细胞。精子和卵子的单倍体原核结合后，合子的发育立即开始，它们的染色体汇聚形成一个带有亲代基因的单倍体细胞核。哺乳动物受精是一系列复杂分子事件的最终结果，这些事件使获能精子能够识别并结合到卵子的细胞外被——透明带（ZP），发生顶体反应，并与卵质膜融合。导致受精的精子 - 透明带（卵子）相互作用是一种物种特异性的碳水化合物介导事件，它依赖于精子质膜上的聚糖识别蛋白（糖基转移酶/糖苷酶/凝集素样分子）（受体）及其在透明带上的互补聚糖单位（配体）。受体 - 配体相互作用事件启动信号转导途径，导致顶体内容物的胞吐作用 。在精子 - 卵子相互作用部位释放的精子糖苷水解酶和蛋白酶的水解作用以及结合精子超活化搏动模式产生的增强推力，是调节卵子保护层穿透的重要因素。本综述重点关注被认为对与女性生殖道相互作用、穿过卵丘和附着于透明带、诱导顶体反应、二次结合事件以及穿过透明带很重要 的精子分子 。了解在导致受精的多个事件中被认为重要的分子的表达和修饰，将有助于制定新的策略来阻断这些修饰并改变精子功能。
