| Modification Notes |
Proteins that contain a RhoGap (Rho GTPase activating protein) domain inactivate regulators of the actin cytoskeleton by catalyzing the hydrolysis of GTP that is bound to Rho, Rac and/or Cdc42. ARHGAP9 (Rho GTPase-activating protein 9) is a 750 amino acid protein that contains a Rho-GAP domain and functions in the activation of Rho-type GTPases by converting them to an inactive GDP-bound state. Predominantly expressed in spleen, thymus and peripheral blood lymphocytes, ARHGAP9 has preferential GAP activity toward Cdc42 and Rac 1, and less activity toward Rho A. Japanese individuals with acetylcholine-induced coronary artery spasm have been found to have a nonsynonymous single nucleotide polymorphism (SNP) in the ARHGAP9 gene, which leads to a weaker inhibitory effect on cell adhesion, spreading and migration than the wild-type protein. This suggests that SNPs within the ARHGAP9 protein play a critical role in the infiltration of hematopoietic cells into the endothelium and inflammation leading to endothelium dysfunction. There are three isoforms of ARHGAP9 that are produced as a result of alternative splicing events. |
