guanine nucleotide-binding protein (G protein) alpha 12
NCBI gene2768
Other data
LocusChr. 7 p22.3
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guanine nucleotide-binding protein (G protein), alpha 13
NCBI gene10672
Other data
LocusChr. 17 q24
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G12/G13 alpha subunits are alpha subunits of heterotrimeric G proteins that link cell surface G protein-coupled receptors primarily to guanine nucleotide exchange factors for the Rho small GTPases to regulate the actin cytoskeleton.[1] Together, these two proteins comprise one of the four classes of G protein alpha subunits.[2] G protein alpha subunits bind to guanine nucleotides and function in a regulatory cycle, and are active when bound to GTP but inactive and associated with the G beta-gamma complex when bound to GDP.[3][4] G12/G13 are not targets of pertussis toxin or cholera toxin, as are other classes of G protein alpha subunits.[5]

G proteins G12 and G13 regulate actin cytoskeletal remodeling in cells during movement and migration, including cancer cell metastasis.[6] G13 is also essential for receptor tyrosine kinase-induced migration of fibroblast and endothelial cells.[7]


See also


  1. ^ Dhanasekaran N, Dermott JM (1996). "Signaling by the G12 class of G proteins". Cell. Signal. 8 (4): 235–45. doi:10.1016/0898-6568(96)00048-4. PMID 8842523.
  2. ^ Strathmann MP, Simon MI (1991). "G alpha 12 and G alpha 13 subunits define a fourth class of G protein alpha subunits". Proc. Natl. Acad. Sci. U.S.A. 88 (13): 5582–6. Bibcode:1991PNAS...88.5582S. doi:10.1073/pnas.88.13.5582. PMC 51921. PMID 1905812.
  3. ^ Gilman AG (1987). "G proteins: transducers of receptor-generated signals". Annual Review of Biochemistry. 56: 615–649. doi:10.1146/ PMID 3113327.
  4. ^ Rodbell M (1995). "Nobel Lecture: Signal transduction: Evolution of an idea". Bioscience Reports. 15 (3): 117–133. doi:10.1007/bf01207453. PMC 1519115. PMID 7579038. S2CID 11025853.
  5. ^ Harhammer R, Nürnberg B, Harteneck C, Leopoldt D, Exner T, Schultz G (1996). "Distinct biochemical properties of the native members of the G12 G-protein subfamily. Characterization of G alpha 12 purified from rat brain". Biochem. J. 319. ( Pt 1) (Pt 1): 165–71. doi:10.1042/bj3190165. PMC 1217750. PMID 8870664.
  6. ^ Wang D, Tan YC, Kreitzer GE, Nakai Y, Shan D, Zheng Y, Huang XY (2006). "G proteins G12 and G13 control the dynamic turnover of growth factor-induced dorsal ruffles". J. Biol. Chem. 281 (43): 32660–7. doi:10.1074/jbc.M604588200. PMID 16943201.
  7. ^ Shan D, Chen L, Wang D, Tan YC, Gu JL, Huang XY (2006). "The G protein G alpha(13) is required for growth factor-induced cell migration". Dev. Cell. 10 (6): 707–18. doi:10.1016/j.devcel.2006.03.014. PMID 16740474.