The pleckstrin homology domain proteins Slm1 and Slm2 are required for actin cytoskeleton organization in yeast and bind phosphatidylinositol-4,5-bisphosphate and TORC2
The pleckstrin homology domain proteins Slm1 and Slm2 are required for actin cytoskeleton organization in yeast and bind phosphatidylinositol-4,5-bisphosphate and TORC2
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DOI：
10.1091/mbc.e04-07-0564
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发表时间：
2005-04-01
影响因子：
3.3
通讯作者：
Kunz, J
中科院分区：
文献类型：
--
作者：
Fadri, M;Daquinag, A;Kunz, J
磷脂酰肌醇-4,5-二磷酸 [PtdIns(4,5)p(2)] 是调节肌动蛋白和膜动力学以及其他细胞过程的关键第二信使。 PtdIns(4,5)p2 的许多作用是通过与含有 pleckstrin 同源 (PH) 结构域的效应蛋白结合介导的。在这里，我们在芽殖酵母酿酒酵母中鉴定了 PtdIns(4,5)P-2 的两个新效应子：包含蛋白质 Slm1 及其同源物 Slm2 的 PH 结构域。 Slm1 和 Slm2 对于细胞生长和肌动蛋白细胞骨架极化起着至关重要的作用。 Slm1 和 Slm2 通过其 PH 结构域结合 PtdIns(4,5)P。此外，Slm1 和 Slm2 与 Avo2 和 Bit61 发生物理相互作用，Avo2 和 Bit61 是 TORC2 信号复合物的两个组成部分，介导 Tor2 信号传导至肌动蛋白细胞骨架。这些相互作用共同协调调节 Slml 靶向质膜。因此，我们的结果确定了 PtdIns(4,5)p2 调节细胞生长和肌动蛋白组织的两个新效应子，并表明 Slml 和 Slm2 整合来自 PtdIns(4,5)p2 和 TORC2 的输入来调节极化肌动蛋白组装和生长。
Phosphatidylinositol-4,5-bisphosphate [PtdIns(4,5)p(2)] is a key second messenger that regulates actin and membrane dynamics, as well as other cellular processes. Many of the effects of PtdIns(4,5)p2 are mediated by binding to effector proteins that contain a pleckstrin homology (PH) domain. Here, we identify two novel effectors of PtdIns(4,5)P-2 in the budding yeast Saccharomyces cerevisiae: the PH domain containing protein Slm1 and its homolog Slm2. Slm1 and Slm2 serve redundant roles essential for cell growth and actin cytoskeleton polarization. Slm1 and Slm2 bind PtdIns(4,5)P, through their PH domains. In addition, Slm1 and Slm2 physically interact with Avo2 and Bit61, two components of the TORC2 signaling complex, which mediates Tor2 signaling to the actin cytoskeleton. Together, these interactions coordinately regulate Slml targeting to the plasma membrane. Our results thus identify two novel effectors of PtdIns(4,5)p2 regulating cell growth and actin organization and suggest that Slml and Slm2 integrate inputs from the PtdIns(4,5)p2 and TORC2 to modulate polarized actin assembly and growth.