Zhao Longmei, Shi Xudong, Li Lingjun, Miller David J
Department of Animal Sciences, University of Illinois, Urbana, Illinois 61801, USA.
Mol Reprod Dev. 2007 Jun;74(6):750-7. doi: 10.1002/mrd.20660.
Previous data showed that complexin I, a SNARE regulatory protein, is localized in and/or around the acrosome and is necessary for the acrosome reaction in sperm. To understand how complexin I regulates the acrosome reaction, we used complexin-GST pulldown assays to identify interacting proteins. We showed that both complexins I and II bound mouse sperm dynamin 2. Dynamin 2 is a 100 kDa GTPase essential to many aspects of endocytosis but its potential role in exocytosis is unknown. Dynamin 2 is expressed in rat testis and widely expressed in other tissues; however, the function of dynamin 2 in germ cells is uncertain. Dynamin 2 protein was detected in mouse testis and was most abundant in or around the developing acrosome of spermatids. In addition, dynamin 2 was co-localized with complexin I in the acrosomal region of mammalian sperm. Its co-localization and interaction with complexin I suggest that dynamin 2 may play a role during acrosome formation and/or acrosomal exocytosis.
先前的数据表明，突触结合蛋白I，一种SNARE调节蛋白，定位于顶体内部和/或周围，是精子顶体反应所必需的。为了了解突触结合蛋白I如何调节顶体反应，我们使用了突触结合蛋白-GST下拉实验来鉴定相互作用蛋白。我们发现突触结合蛋白I和II都能与小鼠精子动力蛋白2结合。动力蛋白2是一种100 kDa的GTP酶，对胞吞作用的许多方面至关重要，但其在胞吐作用中的潜在作用尚不清楚。动力蛋白2在大鼠睾丸中表达，并在其他组织中广泛表达；然而，动力蛋白2在生殖细胞中的功能尚不确定。在小鼠睾丸中检测到了动力蛋白2，并且在精子细胞发育中的顶体内部或周围最为丰富。此外，动力蛋白2与突触结合蛋白I在哺乳动物精子的顶体区域共定位。它与突触结合蛋白I的共定位和相互作用表明，动力蛋白2可能在顶体形成和/或顶体胞吐过程中发挥作用。
