Ras GTPase-activating protein 4 is an enzyme that in humans is encoded by the RASA4gene.[1][2]
This gene encodes a member of the GAP1 family of GTPase-activating proteins that suppresses the Ras/mitogen-activated protein kinase pathway in response to Ca(2+). Stimuli that increase intracellular Ca(2+) levels result in the translocation of this protein to the plasma membrane, where it activates as GTPase activity. Consequently, Ras is converted from the active GTP-bound state to the inactive GDP-bound state and no longer activates downstream pathways that regulate gene expression, cell growth, and differentiation. Multiple transcript variants encoding different isoforms have been found for this gene.[2]
Nagase T, Ishikawa K, Miyajima N, et al. (1998). "Prediction of the coding sequences of unidentified human genes. IX. The complete sequences of 100 new cDNA clones from brain which can code for large proteins in vitro". DNA Res. 5 (1): 31–9. doi:10.1093/dnares/5.1.31. PMID9628581.
Minagawa T, Fukuda M, Mikoshiba K (2001). "Distinct phosphoinositide binding specificity of the GAP1 family proteins: characterization of the pleckstrin homology domains of MRASAL and KIAA0538". Biochem. Biophys. Res. Commun. 288 (1): 87–90. doi:10.1006/bbrc.2001.5740. PMID11594756.
Hillier LW, Fulton RS, Fulton LA, et al. (2003). "The DNA sequence of human chromosome 7". Nature. 424 (6945): 157–64. doi:10.1038/nature01782. PMID12853948.
Ota T, Suzuki Y, Nishikawa T, et al. (2004). "Complete sequencing and characterization of 21,243 full-length human cDNAs". Nat. Genet. 36 (1): 40–5. doi:10.1038/ng1285. PMID14702039.
