title: Interaction of the Nck adapter protein with p21-activated kinase (PAK1).
abstract: The p21-activated kinases (PAKs) link G protein-coupled receptors and growth factor receptors (S. Dharmawardhane, R. H. Daniels, and G. M. Bokoch, submitted for publication) to activation of MAP kinase cascades and to cytoskeletal reorganization (M. A. Sells, U. G. Knaus, D. Ambrose, S. Bagrodia, G. M. Bokoch, and J. Chernoff, submitted for publication). The proteins that interact with PAK to mediate its cellular effects and to couple it to upstream receptors are unknown. We describe here a specific interaction of the Nck adapter molecule with PAK1 both in vitro and in vivo. PAK1 and Nck associate in COS-7 and Swiss 3T3 cells constitutively, but this interaction is strengthened upon platelet-derived growth factor receptor stimulation. We show that Nck binds to PAK1 through its second Src homology 3 (SH3) domain, while PAK1 interacts with Nck via the first proline-rich SH3 binding motif at its amino terminus. The interaction of active PAK1 with Nck leads to the phosphorylation of Nck at multiple sites. Association of Nck with PAK1 may serve to link this important regulatory kinase to cell activation by growth factor receptors.
authors.affiliation: Department of Immunology and Department of Cell Biology, The Scripps Research Institute, La Jolla, California 92037, USA.
authors.forename: G M
authors.initials: GM
authors.lastname: Bokoch
authors.forename: Y
authors.initials: Y
authors.lastname: Wang
authors.forename: B P
authors.initials: BP
authors.lastname: Bohl
authors.forename: M A
authors.initials: MA
authors.lastname: Sells
authors.forename: L A
authors.initials: LA
authors.lastname: Quilliam
authors.forename: U G
authors.initials: UG
authors.lastname: Knaus
mesh_terms: D048868:Adaptor Proteins, Signal Transducing; D000818:Animals; D002460:Cell Line; D017868:Cyclic AMP-Dependent Protein Kinases / Q000378:metabolism; D004789:Enzyme Activation; D051379:Mice; D015513:Oncogene Proteins / Q000378:metabolism*; D010766:Phosphorylation; D010982:Platelet-Derived Growth Factor / Q000378:metabolism; D011392:Proline / Q000378:metabolism; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism*; D020794:Receptor Protein-Tyrosine Kinases / Q000378:metabolism; D017479:Receptors, Platelet-Derived Growth Factor / Q000378:metabolism; D015398:Signal Transduction; D054462:p21-Activated Kinases
chemical_list: D048868:Adaptor Proteins, Signal Transducing; C078332:Nck protein; D015513:Oncogene Proteins; D010982:Platelet-Derived Growth Factor; D011392:Proline; D020794:Receptor Protein-Tyrosine Kinases; D017479:Receptors, Platelet-Derived Growth Factor; C515905:Pak1 protein, mouse; D017346:Protein Serine-Threonine Kinases; D054462:p21-Activated Kinases; D017868:Cyclic AMP-Dependent Protein Kinases