SNAP23 对于小鼠卵母细胞的组成型和调节型胞吐作用是必需的†。
SNAP23 is required for constitutive and regulated exocytosis in mouse oocytes†.
机构信息
Department of Cell Biology, UConn Health, Farmington, Connecticut, USA.
出版信息
Biol Reprod. 2019 Aug 1;101(2):338-346. doi: 10.1093/biolre/ioz106.
Mammalian oocytes are stored in the ovary for prolonged periods, and arrested in meiotic prophase. During this period, their plasma membranes are constantly being recycled by endocytosis and exocytosis. However, the function of this membrane turnover is unknown. Here, we investigated the requirement for exocytosis in the maintenance of meiotic arrest. Using Trim-away, a newly developed method for rapidly and specifically depleting proteins in oocytes, we have identified the SNARE protein, SNAP23, to be required for meiotic arrest. Degradation of SNAP23 causes premature meiotic resumption in follicle-enclosed oocytes. The reduction in SNAP23 is associated with loss of gap junction communication between the oocyte and surrounding follicle cells. Reduction of SNAP23 protein also inhibits regulated exocytosis in response to a Ca2+ stimulus (cortical granule exocytosis), as measured by lectin staining and cleavage of ZP2. Our results show an essential role for SNAP23 in two key processes that occur in mouse oocytes and eggs.
哺乳动物卵母细胞在卵巢中储存很长时间，并在减数分裂前期被阻滞。在此期间，它们的质膜通过内吞作用和外排作用不断被循环利用。然而，这种膜周转的功能尚不清楚。在这里，我们研究了外排作用在维持减数分裂阻滞中的必要性。我们使用新开发的 Trim-away 方法，一种可快速且特异性地耗尽卵母细胞中蛋白质的方法，鉴定出 SNARE 蛋白 SNAP23 对于减数分裂阻滞是必需的。SNAP23 的降解会导致滤泡包被的卵母细胞中减数分裂过早恢复。SNAP23 的减少与卵母细胞和周围滤泡细胞之间的间隙连接通讯丧失有关。SNAP23 蛋白的减少也抑制了对 Ca2+刺激（皮质颗粒胞吐作用）的调节性外排作用，这可以通过凝集素染色和 ZP2 的切割来测量。我们的结果表明 SNAP23 在两个关键过程中发挥着重要作用，这两个过程发生在小鼠卵母细胞和卵子中。
Zotero 插件