Membrane targeting of WAVE2 is not sufficient for WAVE2-dependent actin polymerization: A role for IRSp53 in mediating the interaction between Rac and WAVE2

Wassim Abou-Kheir, Beth Isaac, Hideki Yamaguchi, Dianne Cox

Research output: Contribution to journalArticle

53 Citations (Scopus)

Abstract

Wiskott-Aldrich syndrome protein (WASP)-family verprolin homologous (WAVE) proteins play a major role in Rac-induced actin dynamics, but Rac does not bind directly to WAVE proteins. It has been proposed that either the insulin receptor substrate protein 53 (IRSp53) or a complex of proteins containing Abelson interactor protein 1 (Abil) mediates the interaction of WAVE2 and Rac. Depletion of endogenous IRSp53 by RNA-mediated interference (RNAi) in a RAW/LR5 macrophage cell line resulted in a significant reduction of Rac1Q61L-induced surface ruffles and colony-stimulating factor 1 (CSF-1)-induced actin polymerization, protrusion and cell migration. However, IRSp53 was not essential for Fcγ-R-mediated phagocytosis, formation of podosomes or for formation of Cdc42V12-induced filopodia. IRSp53 was found to be present in an immunoprecipitable complex with WAVE2 and Abil in a Rac1-activation-dependent manner in RAW/LR5 cells in vivo. Importantly, reduction of endogenous IRSp53 or expression of IRSp53 lacking the WAVE2-binding site (IRSp53ΔSH3) resulted in a significant reduction in the association of Rac1 with WAVE2 and Abil, indicating that the association of Rac1 with WAVE2 and Abil is IRSp53 dependent. While it has been proposed that WAVE2 activity is regulated by membrane recruitment, membrane targeting of WAVE2 in RAW/LR5 and Cos-7 cells did not induce actin polymerization or protrusion, suggesting that membrane recruitment was insufficient for regulation of WAVE2. Combined, these data suggest that IRSp53 links Rac1 to WAVE2 in vivo and its function is crucial for production of CSF-1-induced F-actin-rich protrusions and cell migration in macrophages. This study indicates that Rac1, along with IRSp53 and Abil, is involved in a more complex and tight regulation of WAVE2 than one operating solely through membrane localization.

Original languageEnglish (US)
Pages (from-to)379-390
Number of pages12
JournalJournal of Cell Science
Volume121
Issue number3
DOIs
StatePublished - Feb 1 2008

Fingerprint

Insulin Receptor Substrate Proteins
Polymerization
Actins
Membranes
Wiskott-Aldrich Syndrome Protein Family
Macrophage Colony-Stimulating Factor
Cell Movement
Macrophages
Pseudopodia
RNA Interference
Phagocytosis
Proteins
Binding Sites
Cell Line

Keywords

  • Actin
  • Cell migration
  • Chemotaxis
  • IRSp53
  • Macrophage
  • Phagocytosis
  • Rac
  • WAVE2

ASJC Scopus subject areas

  • Cell Biology

Cite this

Membrane targeting of WAVE2 is not sufficient for WAVE2-dependent actin polymerization : A role for IRSp53 in mediating the interaction between Rac and WAVE2. / Abou-Kheir, Wassim; Isaac, Beth; Yamaguchi, Hideki; Cox, Dianne.

In: Journal of Cell Science, Vol. 121, No. 3, 01.02.2008, p. 379-390.

Research output: Contribution to journalArticle

@article{816f3f48c15c46968753686cfa3d3564,
title = "Membrane targeting of WAVE2 is not sufficient for WAVE2-dependent actin polymerization: A role for IRSp53 in mediating the interaction between Rac and WAVE2",
abstract = "Wiskott-Aldrich syndrome protein (WASP)-family verprolin homologous (WAVE) proteins play a major role in Rac-induced actin dynamics, but Rac does not bind directly to WAVE proteins. It has been proposed that either the insulin receptor substrate protein 53 (IRSp53) or a complex of proteins containing Abelson interactor protein 1 (Abil) mediates the interaction of WAVE2 and Rac. Depletion of endogenous IRSp53 by RNA-mediated interference (RNAi) in a RAW/LR5 macrophage cell line resulted in a significant reduction of Rac1Q61L-induced surface ruffles and colony-stimulating factor 1 (CSF-1)-induced actin polymerization, protrusion and cell migration. However, IRSp53 was not essential for Fcγ-R-mediated phagocytosis, formation of podosomes or for formation of Cdc42V12-induced filopodia. IRSp53 was found to be present in an immunoprecipitable complex with WAVE2 and Abil in a Rac1-activation-dependent manner in RAW/LR5 cells in vivo. Importantly, reduction of endogenous IRSp53 or expression of IRSp53 lacking the WAVE2-binding site (IRSp53ΔSH3) resulted in a significant reduction in the association of Rac1 with WAVE2 and Abil, indicating that the association of Rac1 with WAVE2 and Abil is IRSp53 dependent. While it has been proposed that WAVE2 activity is regulated by membrane recruitment, membrane targeting of WAVE2 in RAW/LR5 and Cos-7 cells did not induce actin polymerization or protrusion, suggesting that membrane recruitment was insufficient for regulation of WAVE2. Combined, these data suggest that IRSp53 links Rac1 to WAVE2 in vivo and its function is crucial for production of CSF-1-induced F-actin-rich protrusions and cell migration in macrophages. This study indicates that Rac1, along with IRSp53 and Abil, is involved in a more complex and tight regulation of WAVE2 than one operating solely through membrane localization.",
keywords = "Actin, Cell migration, Chemotaxis, IRSp53, Macrophage, Phagocytosis, Rac, WAVE2",
author = "Wassim Abou-Kheir and Beth Isaac and Hideki Yamaguchi and Dianne Cox",
year = "2008",
month = "2",
day = "1",
doi = "10.1242/jcs.010272",
language = "English (US)",
volume = "121",
pages = "379--390",
journal = "Journal of Cell Science",
issn = "0021-9533",
publisher = "Company of Biologists Ltd",
number = "3",

}

TY - JOUR

T1 - Membrane targeting of WAVE2 is not sufficient for WAVE2-dependent actin polymerization

T2 - A role for IRSp53 in mediating the interaction between Rac and WAVE2

AU - Abou-Kheir, Wassim

AU - Isaac, Beth

AU - Yamaguchi, Hideki

AU - Cox, Dianne

PY - 2008/2/1

Y1 - 2008/2/1

N2 - Wiskott-Aldrich syndrome protein (WASP)-family verprolin homologous (WAVE) proteins play a major role in Rac-induced actin dynamics, but Rac does not bind directly to WAVE proteins. It has been proposed that either the insulin receptor substrate protein 53 (IRSp53) or a complex of proteins containing Abelson interactor protein 1 (Abil) mediates the interaction of WAVE2 and Rac. Depletion of endogenous IRSp53 by RNA-mediated interference (RNAi) in a RAW/LR5 macrophage cell line resulted in a significant reduction of Rac1Q61L-induced surface ruffles and colony-stimulating factor 1 (CSF-1)-induced actin polymerization, protrusion and cell migration. However, IRSp53 was not essential for Fcγ-R-mediated phagocytosis, formation of podosomes or for formation of Cdc42V12-induced filopodia. IRSp53 was found to be present in an immunoprecipitable complex with WAVE2 and Abil in a Rac1-activation-dependent manner in RAW/LR5 cells in vivo. Importantly, reduction of endogenous IRSp53 or expression of IRSp53 lacking the WAVE2-binding site (IRSp53ΔSH3) resulted in a significant reduction in the association of Rac1 with WAVE2 and Abil, indicating that the association of Rac1 with WAVE2 and Abil is IRSp53 dependent. While it has been proposed that WAVE2 activity is regulated by membrane recruitment, membrane targeting of WAVE2 in RAW/LR5 and Cos-7 cells did not induce actin polymerization or protrusion, suggesting that membrane recruitment was insufficient for regulation of WAVE2. Combined, these data suggest that IRSp53 links Rac1 to WAVE2 in vivo and its function is crucial for production of CSF-1-induced F-actin-rich protrusions and cell migration in macrophages. This study indicates that Rac1, along with IRSp53 and Abil, is involved in a more complex and tight regulation of WAVE2 than one operating solely through membrane localization.

AB - Wiskott-Aldrich syndrome protein (WASP)-family verprolin homologous (WAVE) proteins play a major role in Rac-induced actin dynamics, but Rac does not bind directly to WAVE proteins. It has been proposed that either the insulin receptor substrate protein 53 (IRSp53) or a complex of proteins containing Abelson interactor protein 1 (Abil) mediates the interaction of WAVE2 and Rac. Depletion of endogenous IRSp53 by RNA-mediated interference (RNAi) in a RAW/LR5 macrophage cell line resulted in a significant reduction of Rac1Q61L-induced surface ruffles and colony-stimulating factor 1 (CSF-1)-induced actin polymerization, protrusion and cell migration. However, IRSp53 was not essential for Fcγ-R-mediated phagocytosis, formation of podosomes or for formation of Cdc42V12-induced filopodia. IRSp53 was found to be present in an immunoprecipitable complex with WAVE2 and Abil in a Rac1-activation-dependent manner in RAW/LR5 cells in vivo. Importantly, reduction of endogenous IRSp53 or expression of IRSp53 lacking the WAVE2-binding site (IRSp53ΔSH3) resulted in a significant reduction in the association of Rac1 with WAVE2 and Abil, indicating that the association of Rac1 with WAVE2 and Abil is IRSp53 dependent. While it has been proposed that WAVE2 activity is regulated by membrane recruitment, membrane targeting of WAVE2 in RAW/LR5 and Cos-7 cells did not induce actin polymerization or protrusion, suggesting that membrane recruitment was insufficient for regulation of WAVE2. Combined, these data suggest that IRSp53 links Rac1 to WAVE2 in vivo and its function is crucial for production of CSF-1-induced F-actin-rich protrusions and cell migration in macrophages. This study indicates that Rac1, along with IRSp53 and Abil, is involved in a more complex and tight regulation of WAVE2 than one operating solely through membrane localization.

KW - Actin

KW - Cell migration

KW - Chemotaxis

KW - IRSp53

KW - Macrophage

KW - Phagocytosis

KW - Rac

KW - WAVE2

UR - http://www.scopus.com/inward/record.url?scp=40549084647&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=40549084647&partnerID=8YFLogxK

U2 - 10.1242/jcs.010272

DO - 10.1242/jcs.010272

M3 - Article

C2 - 18198193

AN - SCOPUS:40549084647

VL - 121

SP - 379

EP - 390

JO - Journal of Cell Science

JF - Journal of Cell Science

SN - 0021-9533

IS - 3

ER -