A novel neural Wiskott-Aldrich syndrome protein (N-WASP) binding protein, WISH, induces Arp2/3 complex activation independent of Cdc42
A novel neural Wiskott-Aldrich syndrome protein (N-WASP) binding protein, WISH, induces Arp2/3 complex activation independent of Cdc42
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DOI：
10.1083/jcb.152.3.471
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发表时间：
2001-02-05
影响因子：
7.8
通讯作者：
Takenawa, T
中科院分区：
文献类型：
--
作者：
Fukuoka, M;Suetsugu, S;Takenawa, T
我们鉴定了一种新的衔接蛋白，其包含Src同源（SH）3结构域、SH 3结合富含脯氨酸的序列和亮氨酸拉链样基序，并将该蛋白命名为WASP相互作用SH 3蛋白（WISH），WISH主要在神经组织和睾丸中表达，其通过其富含脯氨酸的区域结合Ash/Grb 2，通过其SH 3结构域结合神经Wiskott-Aldrich综合征蛋白（N-WASP），WISH能显著增强N-WASP诱导的Arp 2/3复合物的激活，并能促进肌动蛋白的快速聚合。此外，WISH和N-WASP的共表达能诱导Cos 7细胞形成明显的微刺，即使在无刺激的情况下也是如此。不能结合Cdc 42的N-WASP突变体（H208 D）在与WISH共表达时仍然诱导微刺形成。我们还研究了WISH的贡献，在体外脑提取物诱导的快速肌动蛋白聚合。Arp 2/3复合物是脑提取物诱导肌动蛋白快速聚合所必需的。此外，WISH提取物增加肌动蛋白聚合的Cdc 42没有。然而，WISH出乎意料地可以激活肌动蛋白聚合，即使在N-WASP耗尽提取物。这些结果表明，WISH激活Arp 2/3复合物通过N-WASP依赖和非依赖途径Cdc 42，导致快速肌动蛋白聚合所需的微刺形成。
We identified a novel adaptor protein that contains a Src homology (SH)3 domain, SH3 binding proline-rich sequences, and a leucine zipper-like motif and termed this protein WASP interacting SH3 protein (WISH), WISH is expressed predominantly in neural tissues and testis, It bound Ash/Grb2 through its proline-rich regions and neural Wiskott-Aldrich syndrome protein (N-WASP) through its SH3 domain,WISH strongly enhanced N-WASP-induced Arp2/3 complex activation independent of Cdc42 in vitro, resulting in rapid actin polymerization, Furthermore, coexpression of WISH and N-WASP induced marked formation of microspikes in Cos7 cells, even in the absence of stimuli. An N-WASP mutant (H208D) that cannot bind Cdc42 still induced microspike formation when coexpressed with WISH. We also examined the contribution of WISH to a rapid actin polymerization induced by brain extract in vitro. Arp2/3 complex was essential for brain extract-induced rapid actin polymerization. Addition of WISH to extracts increased actin polymerization as Cdc42 did. However, WISH unexpectedly could activate actin polymerization even in N-WASP-depleted extracts. These findings suggest that WISH activates Arp2/3 complex through N-WASP-dependent and -independent pathways without Cdc42, resulting in the rapid actin polymerization required for microspike formation.