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1mh1
From Proteopedia
SMALL G-PROTEIN
Structural highlights
Function[RAC1_HUMAN] Plasma membrane-associated small GTPase which cycles between active GTP-bound and inactive GDP-bound states. In its active state, binds to a variety of effector proteins to regulate cellular responses such as secretory processes, phagocytosis of apoptotic cells, epithelial cell polarization and growth-factor induced formation of membrane ruffles. Rac1 p21/rho GDI heterodimer is the active component of the cytosolic factor sigma 1, which is involved in stimulation of the NADPH oxidase activity in macrophages (By similarity). Essential for the SPATA13-mediated regulation of cell migration and adhesion assembly and disassembly. Stimulates PKN2 kinase activity. In concert with RAB7A, plays a role in regulating the formation of RBs (ruffled borders) in osteoclasts. In glioma cells, promotes cell migration and invasion.[1] [2] [3] [4] [5] Isoform B has an accelerated GEF-independent GDP/GTP exchange and an impaired GTP hydrolysis, which is restored partially by GTPase-activating proteins. It is able to bind to the GTPase-binding domain of PAK but not full-length PAK in a GTP-dependent manner, suggesting that the insertion does not completely abolish effector interaction.[6] [7] [8] [9] [10] 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 PubMedThe crystal structure of human rac1, a member of the rho family of small G-proteins, complexed with the non-hydrolysable GTP analogue, guanosine-5'-(beta gamma-imino)triphosphate (GMPPNP), has been determined by X-ray analysis at a resolution of 1.38 A. Comparison with the structure of H-ras indicates that rac1 has an extra alpha-helical domain that is characteristic of the rho G proteins, and may be involved in the signalling pathway of this family. The crystal structure of human rac1, a member of the rho-family complexed with a GTP analogue.,Hirshberg M, Stockley RW, Dodson G, Webb MR Nat Struct Biol. 1997 Feb;4(2):147-52. PMID:9033596[11] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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