Replication of the Resident Repressed Epstein-Barr Virus Genome during the Early S Phase (S-1 Period) of Nonproducer Raji Cells

Replication of the resident repressed Epstein-Barr virus genome in synchronized nonproducer Raji cells was shown to occur during the early S phase (S-1 period) by hybridization of cell DNA with virus-specific complementary RNA (cRNA). The S-1 period was previously identified as the critical period for virus activation induced by thymidine analogues. The findings reported here and elsewhere are consistent with the proposal that: (i) virus activation is initiated at or near the site of association of the resident virus genome with cell DNA, (ii) replication of the resident virus genome in nonactivated cells is under cell control mechanisms, and (iii) the resident virus genome is physically associated with early replicating cell DNA.