Format

Send to

Choose Destination
Science. 2000 Oct 27;290(5492):801-6.

Integration of multiple signals through cooperative regulation of the N-WASP-Arp2/3 complex.

Author information

1
Department of Cellular and Molecular Pharmacology, University of California, San Francisco, CA 94143-0450, USA.

Abstract

The protein N-WASP [a homolog to the Wiskott-Aldrich syndrome protein (WASP)] regulates actin polymerization by stimulating the actin-nucleating activity of the actin-related protein 2/3 (Arp2/3) complex. N-WASP is tightly regulated by multiple signals: Only costimulation by Cdc42 and phosphatidylinositol (4,5)-bisphosphate (PIP2) yields potent polymerization. We found that regulation requires N-WASP's constitutively active output domain (VCA) and two regulatory domains: a Cdc42-binding domain and a previously undescribed PIP(2)-binding domain. In the absence of stimuli, the regulatory modules together hold the VCA-Arp2/3 complex in an inactive "closed" conformation. In this state, both the Cdc42- and PIP2-binding sites are masked. Binding of either input destabilizes the closed state and enhances binding of the other input. This cooperative activation mechanism shows how combinations of simple binding domains can be used to integrate and amplify coincident signals.

PMID:
11052943
DOI:
10.1126/science.290.5492.801
[Indexed for MEDLINE]
Free full text

Supplemental Content

Full text links

Icon for HighWire
Loading ...
Support Center