Ras homolog family member B (RhoB)

RhoB, or Ras homolog family member B, is a small GTPase in the Rho subfamily (closely related to RhoA and RhoC) that cycles between GTP-bound active and GDP-bound inactive states to regulate cytoskeletal dynamics, actin organization, and intracellular trafficking. It localizes to plasma membranes, endosomes, multivesicular bodies, and the nucleus due to unique post-translational modifications like farnesylation, geranylgeranylation, and palmitoylation, distinguishing it from RhoA/C. RhoB mediates apoptosis in neoplastically transformed cells post-DNA damage, promotes endothelial cell survival via AKT trafficking during vascular development, and supports cytokinesis through microtubule-dependent signals. In disease, it acts predominantly as a tumor suppressor by inhibiting proliferation, migration, invasion, and genomic instability in cancers like breast, pancreatic, and skin tumors, though its loss correlates with progression in many solid tumors. RhoB also influences inflammation via NFκB activation and macrophage function, and viral infection processes. Farnesyltransferase inhibitors target RhoB by blocking its prenylation, enhancing anti-neoplastic activity, but its pleiotropic roles pose challenges for therapeutic specificity.

Other names

ARH6ARHBh6Rho cDNA clone 6

Inhibition of farnesylation or geranylgeranylation leading to disruption of membrane localization and function; promotion of apoptosis in transformed cells via essential role in genotoxic stress response