RHOV can bind both GTP and GDP, and interacts with effectors when in active, GTP-bound state (Aronheim et al. 1998, Shepelev and Korobko 2012). It should be noted that the binding of both GTP and GDP has never been experimentally confirmed for RHOV in a proper biochemical way. All the assumptions for GTP and GDP binding are inferred from the use of G40V/Q89L “active, GTPase deficient” and S45N “inactive” mutants. Based on the sequence similarity between RHOV and RHOU, it is assumed that RHOV possesses high intrinsic guanine nucleotide exchange activity, but this has not been experimentally confirmed.