Binds and exchanges GTP and GDP. Binds and modulates the activation of POU4F1 as gene expression regulator. GTP + H2O = GDP + H(+) + phosphate Interacts with AFDN, the C-terminal domain of RALGDS and RLF, but not with RIN1 and PIK3CA. RLF binds exclusively to the active GTP-bound form (By similarity). Binds calmodulin. Interacts with PLXNB3. Interacts with POU4F1 (via N-terminus); the interaction controls POU4F1 transactivation activity on some neuronal target genes (By similarity). Colocalizes with PLXNB3 at the plasma membrane (PubMed:16122393). Neuron-specific. Shows rapid uncatalyzed guanine nucleotide dissociation rates, which are much faster than those of most Ras subfamily members. Belongs to the small GTPase superfamily. Ras family.