Interacts with and disrupts the function of host retinoblastoma-related proteins RBR, which are key regulators of the cell cycle. Induces transcriptional activation of E2F-regulated S-phase and G2/M-phase-specific genes. Inactivation of the ability of RBR to arrest the cell cycle leads to the stimulation of viral DNA replication (By similarity). Acts as a suppressor of RNA-mediated gene silencing, also known as post-transcriptional gene silencing (PTGS), a mechanism of plant viral defense that limits the accumulation of viral RNAs. Interacts with host SKP1. Interacts (via LXCXE domain) with host retinoblastoma-related protein 2 (RBR2). Interacts (via LXCXE domain) with human RB1. Interacts (via LXCXE domain) with retinoblastoma-related proteins (RBR) (Probable).