Identification of cofilin and LIM-domain-containing protein kinase 1 as novel interaction partners of 14-3-3 zeta.
Proteins of the 14-3-3 family have been implicated in various physiological processes, and are thought to function as adaptors in various signal transduction pathways. In addition, 14-3-3 proteins may contribute to the reorganization of the actin cytoskeleton by interacting with as yet unidentified actin-binding proteins. Here we show that the 14-3-3 zeta isoform interacts with both the actin-depolymerizing factor cofilin and its regulatory kinase, LIM (Lin-11/Isl-1/Mec-3)-domain-containing protein kinase 1 (LIMK1). In both yeast two-hybrid assays and glutathione S-transferase pull-down experiments, these proteins bound efficiently to 14-3-3 zeta. Deletion analysis revealed consensus 14-3-3 binding sites on both cofilin and LIMK1. Furthermore, the C-terminal region of 14-3-3 zeta inhibited the binding of cofilin to actin in co-sedimentation experiments. Upon co-transfection into COS-7 cells, 14-3-3 zeta-specific immunoreactivity was redistributed into characteristic LIMK1-induced actin aggregations. Our data are consistent with 14-3-3-protein-induced changes to the actin cytoskeleton resulting from interactions with cofilin and/or LIMK1.
D048948:14-3-3 Proteins; D051339:Actin Depolymerizing Factors; D000818:Animals; D001483:Base Sequence; D019556:COS Cells; D002460:Cell Line; D017931:DNA Primers; D004268:DNA-Binding Proteins / Q000378:metabolism*; D006801:Humans; D007150:Immunohistochemistry; D054461:Lim Kinases; D008840:Microfilament Proteins / Q000378:metabolism*; D011485:Protein Binding; D011494:Protein Kinases; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism*; D051381:Rats; D020798:Two-Hybrid System Techniques; D014446:Tyrosine 3-Monooxygenase / Q000378:metabolism*
D048948:14-3-3 Proteins; D051339:Actin Depolymerizing Factors; D017931:DNA Primers; D004268:DNA-Binding Proteins; D008840:Microfilament Proteins; D014446:Tyrosine 3-Monooxygenase; D011494:Protein Kinases; C515892:LIMK1 protein, human; D054461:Lim Kinases; C515894:Limk1 protein, rat; D017346:Protein Serine-Threonine Kinases