| Structural highlights
Function
[PAK1_RAT] Protein kinase involved in intracellular signaling pathways downstream of integrins and receptor-type kinases that plays an important role in cytoskeleton dynamics, in cell adhesion, migration, proliferation, apoptosis, mitosis, and in vesicle-mediated transport processes. Can directly phosphorylate BAD and protects cells against apoptosis. Activated by interaction with CDC42 and RAC1. Functions as GTPase effector that links the Rho-related GTPases CDC42 and RAC1 to the JNK MAP kinase pathway. Phosphorylates and activates MAP2K1, and thereby mediates activation of downstream MAP kinases. Involved in the reorganization of the actin cytoskeleton, actin stress fibers and of focal adhesion complexes. Phosphorylates the tubulin chaperone TBCB and thereby plays a role in the regulation of microtubule biogenesis and organization of the tubulin cytoskeleton. Plays a role in the regulation of insulin secretion in response to elevated glucose levels. Part of a ternary complex that contains PAK1, DVL1 and MUSK that is important for MUSK-dependent regulation of AChR clustering during the formation of the neuromuscular junction (NMJ). Plays a role in CTNNB1 signaling. Activity is inhibited in cells undergoing apoptosis, potentially due to binding of CDC2L1 and CDC2L2. Phosphorylates RAF1 at 'Ser-338' and 'Ser-339' resulting in: activation of RAF1, stimulation of RAF1 translocation to mitochondria, phosphorylation of BAD by RAF1, and RAF1 binding to BCL2. Phosphorylates MYL9/MLC2 (By similarity).[1] [2] [3] [4] [5]
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
The Rho family GTPases, Cdc42, Rac and Rho, regulate signal transduction pathways via interactions with downstream effector proteins. We report here the solution structure of Cdc42 bound to the GTPase binding domain of alphaPAK, an effector of both Cdc42 and Rac. The structure is compared with those of Cdc42 bound to similar fragments of ACK and WASP, two effector proteins that bind only to Cdc42. The N-termini of all three effector fragments bind in an extended conformation to strand beta2 of Cdc42, and contact helices alpha1 and alpha5. The remaining residues bind to switches I and II of Cdc42, but in a significantly different manner. The structure, together with mutagenesis data, suggests reasons for the specificity of these interactions and provides insight into the mechanism of PAK activation.
Structure of Cdc42 bound to the GTPase binding domain of PAK.,Morreale A, Venkatesan M, Mott HR, Owen D, Nietlispach D, Lowe PN, Laue ED Nat Struct Biol. 2000 May;7(5):384-8. PMID:10802735[6]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Manser E, Huang HY, Loo TH, Chen XQ, Dong JM, Leung T, Lim L. Expression of constitutively active alpha-PAK reveals effects of the kinase on actin and focal complexes. Mol Cell Biol. 1997 Mar;17(3):1129-43. PMID:9032240
- ↑ Frost JA, Khokhlatchev A, Stippec S, White MA, Cobb MH. Differential effects of PAK1-activating mutations reveal activity-dependent and -independent effects on cytoskeletal regulation. J Biol Chem. 1998 Oct 23;273(43):28191-8. PMID:9774440
- ↑ Zhao ZS, Manser E, Chen XQ, Chong C, Leung T, Lim L. A conserved negative regulatory region in alphaPAK: inhibition of PAK kinases reveals their morphological roles downstream of Cdc42 and Rac1. Mol Cell Biol. 1998 Apr;18(4):2153-63. PMID:9528787
- ↑ Slack-Davis JK, Eblen ST, Zecevic M, Boerner SA, Tarcsafalvi A, Diaz HB, Marshall MS, Weber MJ, Parsons JT, Catling AD. PAK1 phosphorylation of MEK1 regulates fibronectin-stimulated MAPK activation. J Cell Biol. 2003 Jul 21;162(2):281-91. PMID:12876277 doi:10.1083/jcb.200212141
- ↑ Chen W, Yazicioglu M, Cobb MH. Characterization of OSR1, a member of the mammalian Ste20p/germinal center kinase subfamily. J Biol Chem. 2004 Mar 19;279(12):11129-36. Epub 2004 Jan 5. PMID:14707132 doi:10.1074/jbc.M313562200
- ↑ Morreale A, Venkatesan M, Mott HR, Owen D, Nietlispach D, Lowe PN, Laue ED. Structure of Cdc42 bound to the GTPase binding domain of PAK. Nat Struct Biol. 2000 May;7(5):384-8. PMID:10802735 doi:10.1038/75158
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