title: WAVE2 is regulated by multiple phosphorylation events within its VCA domain.
abstract: The (Wiskott-Aldrich Syndrome Protein)-family verprolin homologous protein (WAVE) family of proteins occupies a pivotal position in the cell, converting extracellular signals into the formation of branched filamentous (F) actin structures. WAVE proteins contain a verprolin central acidic (VCA) domain at their C-terminus, responsible for binding to and activating the Arp2/3 complex, which in-turn nucleates the formation of new actin filaments. Here we identify five Casein Kinase 2 (CK2) phosphorylation sites within the VCA domain of WAVE2, serines 482, 484, 488, 489, and 497. Phosphorylation of these sites is required for a high affinity interaction with the Arp2/3 complex. Phosphorylation of ser 482 and 484 specifically inhibits the activation of the Arp2/3 complex by the WAVE2 VCA domain, but has no effect on the affinity for the Arp2/3 complex when the other phosphorylation sites are occupied. We demonstrate phosphorylation of all five sites on endogenous WAVE2 and show that their mutation to non-phosphorylatable alanine residues inhibits WAVE2 function in vivo, inhibiting cell ruffling and disrupting the integrity of the leading edge of migrating cells.
authors.affiliation: Department of Biochemistry, Faculty of Medical and Veterinary Sciences, University of Bristol, Bristol, United Kingdom.
authors.forename: Shirin M
authors.initials: SM
authors.lastname: Pocha
authors.forename: Giles O
authors.initials: GO
authors.lastname: Cory
mesh_terms: D051376:Actin-Related Protein 2-3 Complex / Q000378:metabolism; D000595:Amino Acid Sequence; D000818:Animals; D019556:COS Cells; D047390:Casein Kinase II / Q000378:metabolism; D002465:Cell Movement / Q000187:drug effects; D002522:Chlorocebus aethiops; D006801:Humans; D051379:Mice; D020928:Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism; D008969:Molecular Sequence Data; D041681:NIH 3T3 Cells; D010766:Phosphorylation / Q000187:drug effects; D047428:Protein Kinase Inhibitors / Q000494:pharmacology; D017434:Protein Structure, Tertiary; D011554:Pseudopodia / Q000187:drug effects / Q000201:enzymology; D051381:Rats; D051300:Wiskott-Aldrich Syndrome Protein Family / Q000737:chemistry* / Q000378:metabolism*
chemical_list: D051376:Actin-Related Protein 2-3 Complex; D047428:Protein Kinase Inhibitors; C120152:WASF2 protein, human; D051300:Wiskott-Aldrich Syndrome Protein Family; D047390:Casein Kinase II; D020928:Mitogen-Activated Protein Kinases