PAK3

PAK3
Available structures PDB Ortholog search: PDBe RCSB List of PDB id codes 1EES
Identifiers
Aliases	PAK3, CDKN1A, MRX30, MRX47, OPHN3, PAK3beta, bPAK, hPAK-3, beta-PAK, ARA, p21 (RAC1) activated kinase 3, XLID30
External IDs	OMIM: 300142 MGI: 1339656 HomoloGene: 55664 GeneCards: PAK3
Gene location (Human) Chr. X chromosome (human)[1] Band Xq23 Start 110,944,285 bp[1] End 111,227,361 bp[1]
Gene location (Mouse) Chr. X chromosome (mouse)[2] Band X|X F2 Start 142,301,587 bp[2] End 142,580,792 bp[2]
RNA expression pattern Bgee Human Mouse (ortholog) Top expressed in middle temporal gyrus Brodmann area 23 endothelial cell entorhinal cortex orbitofrontal cortex postcentral gyrus Brodmann area 46 superior frontal gyrus Region I of hippocampus proper superior vestibular nucleus Top expressed in ventromedial nucleus arcuate nucleus ventral tegmental area lateral hypothalamus paraventricular nucleus of hypothalamus dorsomedial hypothalamic nucleus subiculum mammillary body median eminence dorsal tegmental nucleus More reference expression data BioGPS More reference expression data
Gene ontology Molecular function transferase activity nucleotide binding protein kinase activity SH3 domain binding metal ion binding kinase activity protein binding catalytic activity GTPase binding ATP binding MAP kinase kinase activity protein serine/threonine kinase activity Cellular component cytoplasm cytosol endosome plasma membrane postsynaptic density glutamatergic synapse Biological process regulation of neuron projection development phosphorylation ephrin receptor signaling pathway dendrite development T cell costimulation synapse organization cellular response to organic cyclic compound stimulatory C-type lectin receptor signaling pathway multicellular organism development protein phosphorylation regulation of actin filament polymerization positive regulation of neuron apoptotic process dendritic spine development positive regulation of DNA biosynthetic process metabolism T cell receptor signaling pathway positive regulation of dendritic spine morphogenesis MAPK cascade regulation of actin cytoskeleton organization positive regulation of fibroblast migration dendritic spine morphogenesis Rho protein signal transduction regulation of mitotic cell cycle axonogenesis cell migration stress-activated protein kinase signaling cascade regulation of axonogenesis regulation of apoptotic process signal transduction activation of protein kinase activity regulation of MAPK cascade Sources:Amigo / QuickGO
Orthologs Species Human Mouse Entrez 5063 18481 Ensembl ENSG00000077264 ENSMUSG00000031284 UniProt O75914 Q61036 RefSeq (mRNA) NM_001128166 NM_001128167 NM_001128168 NM_001128172 NM_001128173 NM_002578 NM_001324325 NM_001324326 NM_001324327 NM_001324328 NM_001324329 NM_001324330 NM_001324331 NM_001324332 NM_001324333 NM_001324334 NM_001195046 NM_001195047 NM_001195048 NM_001195049 NM_008778 RefSeq (protein) NP_001121638 NP_001121639 NP_001121640 NP_001121644 NP_001121645 NP_001311254 NP_001311255 NP_001311256 NP_001311257 NP_001311258 NP_001311259 NP_001311260 NP_001311261 NP_001311262 NP_001311263 NP_002569 NP_001181975 NP_001181976 NP_001181977 NP_001181978 NP_032804 Location (UCSC) Chr X: 110.94 – 111.23 Mb Chr X: 142.3 – 142.58 Mb PubMed search [3] [4]
Wikidata
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PAK3 (p21-activated kinase 2, beta-PAK) is one of three members of Group I PAK family of evolutionary conserved serine/threonine kinases.^[5][6][7] PAK3 is preferentially expressed in neuronal cells ^[8][9] and involved in synapse formation and plasticity and mental retardation.^[10][11]

Discovery

PAK3 was initially cloned from a murine fibroblast cDNA library and from a murine embryo cDNA library.^[8][9] Like other group I PAKs, PAK3 is stimulated by activated Cdc42 and Rac1.

Gene and spliced variants

The human PAK3 gene, the longest group I family member, is 283-kb long. The PAK3 gene is composed of 22 exons of which 6 exons are for 5’-UTR and generates 13 alternative spliced transcripts. Among PAK3 transcripts, 11 transcripts are for coding proteins ranging from 181- to 580-amino acids long, while remaining two transcripts are non-coding RNAs.^[12] The murine PAK3 gene contains 10 transcripts, coding six proteins from 544 amino acids and 559 amino acids long, and four smaller polypeptides from 23 to 366 amino acids.

Protein domains

Similar to PAK1, PAK2 contains a p21-binding domain (PBD) and an auto-inhibitory domain (AID) and exists in an inactive conformation.^[13]

Activators and inhibitors

PAK3 activity is stimulated by Dbl, Cdc42 and Cool-2,^[14][15] and by AP1 transcription factor.^[16] Stimulation of PAK3 activity by upstream stimulators such as Dbl or Cdc42 is inhibited by p50 (Cool-1)^[15] PAK3 activity is inhibited by FRAX597, a PAN inhibitor of PAKs.^[17]

Functions

PAK3 is overexpressed in neuroendocrine/carcinoids tumors.^[18] PAK3 has been shown to be important for synapse formation and plasticity, and contribute to mental retardation.^[10] Further, every mutations in the PAK3 gene have been associated with nonsyndromic X-linked mental retardation.^[11]

Notes