The Exo70 subunit of the exocyst is an effector for both Cdc42 and Rho3 function in polarized exocytosis.
The Exo70 subunit of the exocyst is an effector for both Cdc42 and Rho3 function in polarized exocytosis.
复制标题
DOI：
10.1091/mbc.e09-06-0501
复制
发表时间：
2010-02-01
影响因子：
3.3
通讯作者：
Brennwald P
中科院分区：
文献类型：
--
作者：
Wu H;Turner C;Gardner J;Temple B;Brennwald P
遗传和生化证据表明，外囊的Exo70亚基对酵母中的Rho3和CDC42 GTP酶都有直接影响。这些GTP酶的预基化既促进了相互作用，又影响了Exo70内的结合部位。因此，Rho GTP酶与Exo70的相互作用是胞吐作用空间调控的关键事件。Rho GTP酶家族中的Rho3和CDC42成员是酵母胞吐作用的重要调节因子。然而，他们监管这一过程的确切机制存在争议。在这里，我们提出的证据表明，胞囊复合体的Exo70成分是Rho3和Cdc42的直接效应因子。我们在Exo70中发现了功能增益突变体，这些突变体有效地抑制了Rho3和Cdc42中具有胞外功能缺陷的突变体。我们证明了Exo70具有Rho3和CdC42的直接效应器所期望的生化特性。令人惊讶的是，我们发现这些GTP酶的C末端预烯基化既促进了相互作用，又影响了Exo70内的结合位点。最后，我们证明了Exo70中新的功能缺失突变的表型与Exo70作为Rho3和Cdc42分泌功能效应器的表型完全一致。这些数据表明，与胞囊Exo70成分的相互作用是Rho GTP酶对胞吐作用进行空间调控的关键事件。
Genetic and biochemical evidence is presented that the Exo70 subunit of the exocyst is a direct effector for both Rho3 and Cdc42 GTPases in yeast. Prenylation of these GTPases both promotes the interaction and affects the site of binding within Exo70. Thus, interaction of the Rho GTPases with Exo70 is a key event in spatial regulation of exocytosis. The Rho3 and Cdc42 members of the Rho GTPase family are important regulators of exocytosis in yeast. However, the precise mechanism by which they regulate this process is controversial. Here, we present evidence that the Exo70 component of the exocyst complex is a direct effector of both Rho3 and Cdc42. We identify gain-of-function mutants in EXO70 that potently suppress mutants in RHO3 and CDC42 defective for exocytic function. We show that Exo70 has the biochemical properties expected of a direct effector for both Rho3 and Cdc42. Surprisingly, we find that C-terminal prenylation of these GTPases both promotes the interaction and influences the sites of binding within Exo70. Finally, we demonstrate that the phenotypes associated with novel loss-of-function mutants in EXO70, are entirely consistent with Exo70 as an effector for both Rho3 and Cdc42 function in secretion. These data suggest that interaction with the Exo70 component of the exocyst is a key event in spatial regulation of exocytosis by Rho GTPases.
登录
查看更多内容
影响因子：
5.6
作者：
Hamburger, ZA;Hamburger, AE;Weis, WI
通讯作者：
Weis, WI
影响因子：
16.8
作者：
Dong, G;Hutagalung, AH;Reinisch, KM
通讯作者：
Reinisch, KM
影响因子：
19
作者：
Wu H;Rossi G;Brennwald P
通讯作者：
Brennwald P
酵母CDC42在胞吐作用的后期发挥作用，特别是在新兴芽的极化生长过程中。
影响因子：
7.8
作者：
Adamo, JE;Moskow, JJ;Gladfelter, AS;Viterbo, D;Lew, DJ;Brennwald, PJ
通讯作者：
Brennwald, PJ
影响因子：
4.4
作者：
Guo FB;Yu XJ
通讯作者：
Yu XJ