The cell polarity proteins Boi1 and Boi2 direct an actin nucleation complex to sites of exocytosis in Saccharomyces cerevisiae
The cell polarity proteins Boi1 and Boi2 direct an actin nucleation complex to sites of exocytosis in Saccharomyces cerevisiae
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DOI：
10.1242/jcs.237982
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发表时间：
2020-02-01
影响因子：
4
通讯作者：
Johnsson, Nils
中科院分区：
文献类型：
--
作者：
Glomb, Oliver;Wu, Yehui;Johnsson, Nils
由于影响其动力学和组织的因素的局部富集性，肌动蛋白细胞骨架在同一细胞内表现出不同的形状和功能。在酵母细胞中，高尔基体后的囊泡通过长长的肌动蛋白缆索到达芽尖。蛋白质Boi1和Boi2(Boi1/2)参与将这些小泡连接和对接到质膜上。在这里，我们在酿酒酵母中证明了Boi1/2还招募了成核和伸长因子来在胞吐部位形成肌动蛋白细丝。破坏Boi1/2和成核因子Bud6之间的连接会损害细丝的形成，减少囊泡向顶端的定向运动，并缩短囊泡在皮质的拴系时间。将boil从芽尖移植到过氧化体膜上，部分地将肌动蛋白细胞骨架和囊泡流向过氧化酶体，并创建了一个替代的、残存的囊泡对接区。我们得出结论，Boi1/2通过与Bud6和Bni1相互作用，诱导皮质肌动蛋白结构的形成，该结构在与膜融合之前接收并排列传入的小泡。
Owing to the local enrichment of factors that influence its dynamics and organization, the actin cytoskeleton displays different shapes and functions within the same cell. In yeast cells, post-Golgi vesicles ride on long actin cables to the bud tip. The proteins Boi1 and Boi2 (Boi1/2) participate in tethering and docking these vesicles to the plasma membrane. Here, we show in Saccharomyces cerevisiae that Boi1/2 also recruit nucleation and elongation factors to form actin filaments at sites of exocytosis. Disrupting the connection between Boi1/2 and the nucleation factor Bud6 impairs filament formation, reduces the directed movement of the vesicles to the tip and shortens the vesicles' tethering time at the cortex. Transplanting Boil from the bud tip to the peroxisomal membrane partially redirects the actin cytoskeleton and the vesicular flow towards the peroxisome, and creates an alternative, rudimentary vesicle-docking zone. We conclude that Boi1/2, through interactions with Bud6 and Bni1, induce the formation of a cortical actin structure that receives and aligns incoming vesicles before fusion with the membrane.