Roles of Mso1 and the SM protein Sec1 in efficient vesicle fusion during fission yeast cytokinesis.
Roles of Mso1 and the SM protein Sec1 in efficient vesicle fusion during fission yeast cytokinesis.
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DOI：
10.1091/mbc.e20-01-0067
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发表时间：
2020-07-15
影响因子：
3.3
通讯作者：
Wu JQ
中科院分区：
文献类型：
--
作者：
Gerien KS;Zhang S;Russell AC;Zhu YH;Purde V;Wu JQ
胞质分裂期间的膜运输对于将膜脂和货物递送至分裂位点至关重要。然而，其分子机制仍不完全清楚。在这项研究中，我们证明了未表征的裂殖酵母蛋白 Mso1 和 Sec1 在胞质分裂过程中膜运输中的重要性。裂殖酵母 Mso1 与出芽酵母 Mso1 和人 Mint1 具有同源性，后者是在囊泡融合过程中与 Sec1/Munc18 家族蛋白相互作用的蛋白质。 Sec1/Munc18 蛋白及其相互作用子是囊泡融合过程中 SNARE 复合物形成的重要调节因子。这些蛋白质在胞质分裂期间囊泡运输中的作用几乎没有被研究过。在这里，我们证明裂殖酵母 Mso1 也是一种 Sec1 结合蛋白，并且 Mso1 和 Sec1 在胞质分裂过程中相互依赖地定位于分裂位点。 mso1Δ 细胞中 Sec1 定位的丧失导致囊泡融合减少和胞质分裂缺陷，例如缓慢的环收缩、有缺陷的环分解和延迟的质膜闭合。我们还发现 Mso1 和 Sec1 可能具有独立于分裂位点质膜上的外囊束缚复合物的功能。 Mso1 和 Sec1 一起在胞质分裂过程中调节囊泡融合和分裂位点的货物递送中发挥重要作用。
Membrane trafficking during cytokinesis is essential for the delivery of membrane lipids and cargoes to the division site. However, the molecular mechanisms are still incompletely understood. In this study, we demonstrate the importance of uncharacterized fission yeast proteins Mso1 and Sec1 in membrane trafficking during cytokinesis. Fission yeast Mso1 shares homology with budding yeast Mso1 and human Mint1, proteins that interact with Sec1/Munc18 family proteins during vesicle fusion. Sec1/Munc18 proteins and their interactors are important regulators of SNARE complex formation during vesicle fusion. The roles of these proteins in vesicle trafficking during cytokinesis have been barely studied. Here, we show that fission yeast Mso1 is also a Sec1-binding protein and Mso1 and Sec1 localize to the division site interdependently during cytokinesis. The loss of Sec1 localization in mso1Δ cells results in a decrease in vesicle fusion and cytokinesis defects such as slow ring constriction, defective ring disassembly, and delayed plasma membrane closure. We also find that Mso1 and Sec1 may have functions independent of the exocyst tethering complex on the plasma membrane at the division site. Together, Mso1 and Sec1 play essential roles in regulating vesicle fusion and cargo delivery at the division site during cytokinesis.