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Arp2/3 complex-deficient mouse fibroblasts are viable and have normal leading-edge actin structure and function.

ABSTRACT: RNA interference silencing of up to 90% of Arp3 protein expression, a major subunit of the Arp2/3 complex, proportionately decreases the intracellular motility of Listeria monocytogenes and actin nucleation activity ascribable to the Arp2/3 complex in mouse embryonic fibroblasts. However, the Arp2/3-deficient cells exhibit unimpaired lamellipodial actin network structure, translational locomotion, spreading, actin assembly, and ruffling responses. In addition, Arp3-silenced cells expressing neural Wiskott-Aldrich syndrome protein-derived peptides that inhibit Arp2/3 complex function in wild-type cells retained normal PDGF-induced ruffling. The Arp2/3 complex can be dispensable for leading-edge actin remodeling.

SUBMITTER: Di Nardo A

PROVIDER: S-EPMC1283463 | biostudies-literature | 2005 Nov

REPOSITORIES: biostudies-literature

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Arp2/3 complex-deficient mouse fibroblasts are viable and have normal leading-edge actin structure and function.

Di Nardo Alessia A Cicchetti Gregor G Falet Hervé H Hartwig John H JH Stossel Thomas P TP Kwiatkowski David J DJ

Proceedings of the National Academy of Sciences of the United States of America 20051027 45

RNA interference silencing of up to 90% of Arp3 protein expression, a major subunit of the Arp2/3 complex, proportionately decreases the intracellular motility of Listeria monocytogenes and actin nucleation activity ascribable to the Arp2/3 complex in mouse embryonic fibroblasts. However, the Arp2/3-deficient cells exhibit unimpaired lamellipodial actin network structure, translational locomotion, spreading, actin assembly, and ruffling responses. In addition, Arp3-silenced cells expressing neur ...[more]

PMID: 16254049

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