PAK3 Serine/threonine protein kinase that plays a role in a variety of different signaling pathways including cytoskeleton regulation, cell migration, or cell cycle regulation. Plays a role in dendrite spine morphogenesis as well as synapse formation and plasticity. Acts as downstream effector of the small GTPases CDC42 and RAC1. Activation by the binding of active CDC42 and RAC1 results in a conformational change and a subsequent autophosphorylation on several serine and/or threonine residues. Phosphorylates MAPK4 and MAPK6 and activates the downstream target MAPKAPK5, a regulator of F-actin polymerization and cell migration. Additionally, phosphorylates TNNI3/troponin I to modulate calcium sensitivity and relaxation kinetics of thin myofilaments. May also be involved in early neuronal development. Belongs to the protein kinase superfamily. STE Ser/Thr protein kinase family. STE20 subfamily. Restricted to the nervous system. Highly expressed in postmitotic neurons of the developing and postnatal cerebral cortex and hippocampus. 4 alternatively spliced human isoforms have been reported. Note: This description may include information from UniProtKB.
Protein type: EC; Kinase, protein; PAKA subfamily; Protein kinase, STE; Protein kinase, Ser/Thr (non-receptor); STE group; STE20 family
Chromosomal Location of human Ortholog: Xq23
Cellular Component:  cytosol; endosome; glutamatergic synapse; plasma membrane; postsynaptic density
Molecular Function:  ATP binding; MAP kinase kinase activity; metal ion binding; protein binding; protein serine/threonine kinase activity; SH3 domain binding
Biological Process:  activation of MAPK activity; axonogenesis; cellular response to organic cyclic compound; dendrite development; dendritic spine morphogenesis; ephrin receptor signaling pathway; MAPK cascade; positive regulation of dendritic spine morphogenesis; positive regulation of DNA biosynthetic process; positive regulation of fibroblast migration; positive regulation of neuron apoptotic process; regulation of actin filament polymerization; stimulatory C-type lectin receptor signaling pathway; synapse organization; T cell costimulation; T cell receptor signaling pathway
Disease: Mental Retardation, X-linked 30
Reference #:  O75914 (UniProtKB)
Alt. Names/Synonyms: adriamycin resistance-associated; ARA; Beta-PAK; bPAK; CDKN1A; hPAK3; MRX30; MRX47; Oligophrenin-3; OPHN3; p21 (CDKN1A)-activated kinase 3; p21 (RAC1) activated kinase 3; p21 protein (Cdc42/Rac)-activated kinase 3; p21-activated kinase 3; PAK-3; PAK3; PAK3beta; Serine/threonine-protein kinase PAK 3
Gene Symbols: PAK3
Molecular weight: 62,310 Da
Basal Isoelectric point: 5.33  Predict pI for various phosphorylation states
CST Pathways:  Growth And Differentiation Control by MAPKs  |  Microtubule Dynamics  |  TGF-ß Signaling
Protein-Specific Antibodies, siRNAs or Recombinant Proteins from Cell Signaling Technology® Total Proteins
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Cross-references to other databases:  AlphaFold  |  STRING  |  cBioPortal  |  Wikipedia  |  Reactome  |  neXtProt  |  Protein Atlas  |  BioGPS  |  KinBase  |  Pfam  |  RCSB PDB  |  ENZYME  |  Phospho.ELM  |  NetworKIN  |  GeneCards  |  UniProtKB  |  Entrez-Gene  |  GenPept  |  Ensembl Gene  |  Ensembl Protein