Urner Françoise, Sakkas Denny
Clinic of Sterility, Department of Obstetrics and Gynecology, University Hospital of Geneva, 1211 Geneva 14, Switzerland.
Reproduction. 2003 Jan;125(1):17-26. doi: 10.1530/rep.0.1250017.
Spermatozoa undergo a series of changes before and during egg binding to acquire the ability to fuse with the oocyte. These priming events are regulated by the activation of compartmentalized intracellular signalling pathways, which control the phosphorylation status of sperm proteins. Increased protein tyrosine phosphorylation is associated with capacitation, hyperactivated motility, zona pellucida binding, acrosome reaction and sperm-oocyte binding and fusion. The main tyrosine phosphorylated proteins during the course of capacitation and fertilization are localized to the flagellum, although tyrosine phosphorylation of less abundant proteins may also be regulated in the sperm head. Spermatozoa bound to the zona pellucida and fusing with the oocyte plasma membrane are characterized by a tyrosine phosphorylated flagellum. Protein phosphorylation in the flagellum is linked to hyperactivated motility in spermatozoa, but may also regulate additional functions involved in sperm-oocyte fusion. Factors involved in the appearance of phosphorylation more likely arise from the milieu surrounding the spermatozoa, but their uptake and processing are likely to be regulated differentially at specific steps within the female genital tract and during penetration of the egg vestments. One of these factors is glucose, the metabolic products of which (ATP and NADPH) appear to participate in signalling pathways by supporting a precise onset of tyrosine phosphorylation in the sperm flagellum leading to successful fertilization.
精子在与卵子结合之前及过程中会经历一系列变化，以获得与卵母细胞融合的能力。这些引发事件由分隔的细胞内信号通路的激活来调控，该信号通路控制精子蛋白的磷酸化状态。蛋白质酪氨酸磷酸化增加与获能、超活化运动、透明带结合、顶体反应以及精子 - 卵母细胞结合与融合相关。在获能和受精过程中，主要的酪氨酸磷酸化蛋白定位于鞭毛，尽管精子头部中较少丰度蛋白的酪氨酸磷酸化也可能受到调控。与透明带结合并与卵母细胞质膜融合的精子的特征是鞭毛酪氨酸磷酸化。鞭毛中的蛋白质磷酸化与精子的超活化运动有关，但也可能调节精子 - 卵母细胞融合中涉及的其他功能。参与磷酸化出现的因素更可能来自精子周围的环境，但其摄取和加工可能在女性生殖道内的特定步骤以及穿透卵膜期间受到不同的调控。其中一个因素是葡萄糖，其代谢产物（ATP 和 NADPH）似乎通过支持精子鞭毛中酪氨酸磷酸化的精确起始参与信号通路，从而导致成功受精。
