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Cooperative interactions at the SLP-76 complex are critical for actin polymerization.

ABSTRACT: T-cell antigen receptor (TCR) engagement induces formation of multi-protein signalling complexes essential for regulating T-cell functions. Generation of a complex of SLP-76, Nck and VAV1 is crucial for regulation of the actin machinery. We define the composition, stoichiometry and specificity of interactions in the SLP-76, Nck and VAV1 complex. Our data reveal that this complex can contain one SLP-76 molecule, two Nck and two VAV1 molecules. A direct interaction between Nck and VAV1 is mediated by binding between the C-terminal SH3 domain of Nck and the VAV1 N-terminal SH3 domain. Disruption of the VAV1:Nck interaction deleteriously affected actin polymerization. These novel findings shed new light on the mechanism of actin polymerization after T-cell activation.

SUBMITTER: Barda-Saad M

PROVIDER: S-EPMC2910278 | biostudies-literature | 2010 Jul

REPOSITORIES: biostudies-literature

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Cooperative interactions at the SLP-76 complex are critical for actin polymerization.

Barda-Saad Mira M Shirasu Naoto N Pauker Maor H MH Hassan Nirit N Perl Orly O Balbo Andrea A Yamaguchi Hiroshi H Houtman Jon C D JC Appella Ettore E Schuck Peter P Samelson Lawrence E LE

The EMBO journal 20100618 14

T-cell antigen receptor (TCR) engagement induces formation of multi-protein signalling complexes essential for regulating T-cell functions. Generation of a complex of SLP-76, Nck and VAV1 is crucial for regulation of the actin machinery. We define the composition, stoichiometry and specificity of interactions in the SLP-76, Nck and VAV1 complex. Our data reveal that this complex can contain one SLP-76 molecule, two Nck and two VAV1 molecules. A direct interaction between Nck and VAV1 is mediated ...[more]

PMID: 20562827

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