Viral protein R 105 Stimulates gene expression driven by the HIV-2 LTR. Prevents infected cells from undergoing mitosis and proliferating, by inducing arrest or delay in the G2 phase of the cell cycle. Cell cycle arrest creates a favourable environment for maximizing viral expression and production (By similarity). vpr R ORF protein Protein Vpr VPR_HV2D1 MTEAPTEFPPEDGTPRRELGSTWVIETLKEIKEEALKHFDPCLLIALGNYIYNRHGDTLEGARELIRVLQRALFVHIRAGCDRSRKGQTRRRAPCPAAPTPRGMH