HIV-1 Nef is a 27kDa protein highly produced after a very short time after virus infection. HIV-1 Nef is an essential factor for efficient viral replication and phatogenesis.
HIV-1 Nef facilitates virus replication and improves virions infectivity. HIV-1 Nef exerts pleiotropic effect. HIV-1 Nef down-modulates surface MHC-I molecules， decreases cell surface CD4 antigen by interacting with the Src family kinase LCK thereby inducing LCK-CD4 dissociation and by increasing clathrindependent endocytosis of this antigen to target it to lysosomial degradation. HIV-1 Nef guards the infected cell from apoptosis in order to keep it alive until the next virus generation is ready to strike. HIV-1 Nef protein bypasses host Tcell signaling by inducing a transcriptional program nearly identical to that of anti-CD3 cell activation.
