摘要
One of the most important processes in fertilization is the fusion of egg and sperm; however, the molecular mechanisms involved in this process are not well understood. So far, using genetic approaches, only two proteins have been demonstrated to be necessary for this process: Izumo in sperm and CD9 in the egg. Here we demonstrate that sperm produced by Tssk6 (Sstk)-null mice present defects that prevent the successful fertilization of eggs in vitro and the fusion to zona-pellucida-free eggs. Tssk6 is a member of the testis-specific serine kinase family of proteins and is expressed postmeiotically in male germ cells. In order for fusion to occur, during the process known as acrosome reaction Izumo needs to relocate from the anterior head to other regions, including the postacrosomal compartment. Tssk6-null sperm fails to relocate Izumo during the acrosome reaction. Agents that interfere with actin dynamics blocked the acrosome-reaction-associated translocation of Izumo that is required for fusion in wild-type sperm. Additionally, actin polymerization was compromised in Tssk6-null sperm. Taken together, our results indicate that Tssk6 is involved in sperm-egg fusion through the regulation of actin polymerization and changes in Izumo localization.
摘要译文
一个在受精的最重要的过程是卵子和精子的融合;然而，参与这一过程的分子机制尚不十分清楚。到目前为止，用遗传方法，只有两种蛋白已被证明是必要的这一过程：出云在精子和CD9的蛋。在这里，我们证明了Tssk6（Sstk）产生的精子-null小鼠目前的缺陷，以防止卵的体外成功受精和融合透明带透明带免费鸡蛋。Tssk6是蛋白质的睾丸特异性丝氨酸激酶家族的成员，并且是postmeiotically表示在雄性生殖细胞。为了融合发生，期间被称为顶体反应出云需要来自前头部移居到其他区域，包括postacrosomal室中的过程。Tssk6空精子未能顶体反应过程中搬迁出云。与肌动蛋白动力学干扰剂受阻出云的顶体反应相关的易位所需融合在野生型精子。此外，肌动蛋白聚合失密，Tssk6空的精子。两者合计，我们的研究结果表明，Tssk6参与精卵融合，通过肌动蛋白聚合和变化，出云的本地化的调节。
Sosnik J; Miranda PV; Spiridonov NA; Yoon SY; Fissore RA; Johnson GR; Visconti PE. Tssk6 is required for Izumo relocalization and gamete fusion in the mouse.[J]. Journal of Cell Science, 2009,122(15): 2741-2749