African Swine Fever Virus Manipulates the Cell Cycle of G0-Infected Cells to Access Cellular Nucleotides.

Abstract

African swine fever virus manipulates the cell cycle of infected G0 cells by inducing its progression via unblocking cells from the G0 to S phase and then arresting them in the G2 phase. DNA synthesis in infected alveolar macrophages starts at 10–12 h post infection. DNA synthesis in the nuclei of G0 cells is preceded by the activation of the viral genes K196R, A240L, E165R, F334L, F778R, and R298L involved in the synthesis of nucleotides and the regulation of the cell cycle. The activation of these genes in actively replicating cells begins later and is less pronounced. The subsequent cell cycle arrest at the G2 phase is also due to the cessation of the synthesis of cellular factors that control the progression of the cell cycle–cyclins. This data describes the manipulation of the cell cycle by the virus to gain access to the nucleotides synthesized by the cell. The genes affecting the cell cycle simply remain disabled until the beginning of cellular DNA synthesis (8–9 hpi). The genes responsible for the synthesis of nucleotides are turned on later in the presence of nucleotides and their transcriptional activity is lower than that during virus replication in an environment without nucleotides.