a protein kinase of the STE20 family. A mediator of filopodia formation and may play a role in the reorganization of the actin cytoskeleton. Interacts specifically with the GTP-bound form of Cdc42 and weakly activates the JNK family of MAP kinases. Overexpressed in several cancers. Required for ras-dependent anchorage-independent growth of tumor cell lines. Four alternatively spliced human isoforms have been reported. Note: This description may include information from UniProtKB.
Protein type: EC 22.214.171.124; Kinase, protein; PAKB subfamily; Protein kinase, STE; Protein kinase, Ser/Thr (non-receptor); STE group; STE20 family
Molecular Function: protein binding; protein serine/threonine kinase activity; Rac GTPase binding
Biological Process: actin cytoskeleton organization and biogenesis; activation of protein kinase activity; apoptosis; cell growth; cell migration; cell motility; cell proliferation; cytoskeleton organization and biogenesis; regulation of apoptosis; regulation of MAPKKK cascade; regulation of mitotic cell cycle; Rho protein signal transduction; signal transduction; stress-activated protein kinase signaling pathway
Alt. Names/Synonyms: KIAA1142; p21 protein (Cdc42/Rac)-activated kinase 4; p21(CDKN1A)-activated kinase 4; p21-activated kinase 4; PAK-4; PAK4; protein kinase related to S. cerevisiae STE20, effector for Cdc42Hs; Serine/threonine-protein kinase PAK 4