Viral protein involved in the modulation of host cell cycle. The cell cycle can be divided into four stages: G1, S, G2 and mitosis, while cells resting are termed quiescent cells (G0). Viruses have evolved strategies to modulate cell cycle progression including stimulation of S phase entry from G1 or G0 or cell cycle arrest at G2/M for example. This regulation allows viruses to maximize their own replication.

› Biological process

› modulation by virus of host cell cycle [ GO:0060153 ]