Biology:GTPase-activator protein for Ras-like GTPase

From HandWiki
Short description: Protein family
GTPase-activator protein for Ras-like GTPase
Identifiers
SymbolRasGAP
PfamPF00616
InterProIPR001936
SMARTRasGAP
SCOP21wer / SCOPe / SUPFAM
CDDcd04519

GTPase-activator protein for Ras-like GTPase is a family of evolutionarily related proteins. Ras proteins are membrane-associated molecular switches that bind GTP and GDP and slowly hydrolyze GTP to GDP.[1] This intrinsic GTPase activity of ras is stimulated by a family of proteins collectively known as 'GAP' or GTPase-activating proteins.[2][3] As it is the GTP bound form of ras which is active, these proteins are said to be down-regulators of ras.

The Ras GTPase-activating proteins are quite large (from 765 residues for sar1 to 3079 residues for IRA2) but share only a limited (about 250 residues) region of sequence similarity, referred to as the 'catalytic domain' or rasGAP domain.

Note: There are distinctly different GAPs for the rap and rho/rac subfamilies of ras-like proteins (reviewed in reference[4]) that do not share sequence similarity with ras GAPs.

Examples

Human genes encoding proteins containing this domain include:

References

  1. "The GTPase superfamily: conserved structure and molecular mechanism". Nature 349 (6305): 117–127. 1991. doi:10.1038/349117a0. PMID 1898771. Bibcode1991Natur.349..117B. 
  2. "sar1, a gene from Schizosaccharomyces pombe encoding a protein that regulates ras1". Cell Regul. 2 (6): 453–465. 1991. doi:10.1091/mbc.2.6.453. PMID 1883874. 
  3. "Regulation of the Ras signalling network". BioEssays 16 (7): 489–496. 1994. doi:10.1002/bies.950160708. PMID 7945277. 
  4. "Proteins regulating Ras and its relatives". Nature 366 (6456): 643–654. 1993. doi:10.1038/366643a0. PMID 8259209. Bibcode1993Natur.366..643B. 
This article incorporates text from the public domain Pfam and InterPro: IPR001936