Protein kinase D controls actin polymerization and cell motility through phosphorylation of cortactin.
We here identify protein kinase D (PKD) as an upstream regulator of the F-actin-binding protein cortactin and the Arp actin polymerization machinery. PKD phosphorylates cortactin in vitro and in vivo at serine 298 thereby generating a 14-3-3 binding motif. In vitro, a phosphorylation-deficient cortactin-S298A protein accelerated VCA-Arp-cortactin-mediated synergistic actin polymerization and showed reduced F-actin binding, indicative of enhanced turnover of nucleation complexes. In vivo, cortactin co-localized with the nucleation promoting factor WAVE2, essential for lamellipodia extension, in the actin polymerization zone in Heregulin-treated MCF-7 cells. Using a 3-dye FRET-based approach we further demonstrate that WAVE2-Arp and cortactin prominently interact at these structures. Accordingly, cortactin-S298A significantly enhanced lamellipodia extension and directed cell migration. Our data thus unravel a previously unrecognized mechanism by which PKD controls cancer cell motility.
Eiseler
Tim
T
Institute of Cell Biology and Immunology, University of Stuttgart, Stuttgart 70569, Germany.
Hausser
Angelika
A
De Kimpe
Line
L
Van Lint
Johan
J
Pfizenmaier
Klaus
K
D000199:Actins / Q000737:chemistry*; D020816:Amino Acid Motifs; D002460:Cell Line; D045744:Cell Line, Tumor; D002465:Cell Movement; D051356:Cortactin / Q000737:chemistry*; D031541:Fluorescence Resonance Energy Transfer; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D020890:Neuregulin-1 / Q000737:chemistry; D010766:Phosphorylation; D011485:Protein Binding; D011493:Protein Kinase C / Q000737:chemistry*; D051300:Wiskott-Aldrich Syndrome Protein Family / Q000737:chemistry
D000199:Actins; D051356:Cortactin; D020890:Neuregulin-1; C120152:WASF2 protein, human; D051300:Wiskott-Aldrich Syndrome Protein Family; C089212:protein kinase D; D011493:Protein Kinase C