RhoG

RhoG (Ras homology Growth-related) (or ARGH) is a small (~21 kDa) monomeric GTP-binding protein (G protein), and is an important component of many intracellular signalling pathways. It is a member of the Rac subfamily of the Rho family of small G proteins and is encoded by the gene RHOG.

Discovery

RhoG was first identified as a coding sequence upregulated in hamster lung fibroblasts upon stimulation with serum. Expression of RhoG in mammals is widespread and studies of its function have been carried out in fibroblasts,leukocytes,neuronal cells,endothelial cells and HeLa cells. RhoG belongs to the Rac subgroup and emerged as a consequence of retroposition in early vertebrates. RhoG shares a subset of common binding partners with Rac, Cdc42 and RhoU/V members but a major specificity is its inability to bind to CRIB domain proteins such as PAKs.

Function

Like most small G proteins RhoG is involved in a diverse set of cellular signalling mechanisms. In mammalian cells these include cell motility (through regulation of the actin cytoskeleton),gene transcription,endocytosis,neurite outgrowth, protection from anoikis and regulation of the neutrophil NADPH oxidase.