Binds GTP and exhibits intrinsic GTPase activity. May activate NF-kappa-B-mediated gene transcription. Promotes signal transduction through MTOR, activates RPS6KB1, and is a downstream target of the small GTPase-activating proteins TSC1 and TSC2. Interacts with MTOR. Ubiquitously expressed. Expression increased at least 2-fold in several tumor cell lines. May be produced at very low levels due to a premature stop codon in the mRNA, leading to nonsense-mediated mRNA decay. Belongs to the small GTPase superfamily. Rheb family. Wrong choice of CDS.