The induction of cellular DNA synthesis in G1-arrested BKH21 cell infected with adenovirus type 2.

G1-arrested BHK21 cells infected with adenovirus type 2 were studied to determine the effect of infection on host DNA synthesis in a productive cycle of infection. At various intervals following infection, analysis of the intracellular DNA was carried out by zonal sedimentation centrifugation through alkaline sucrose gradients. In addition to material which sedimented to the position of the virus markers (34S), a class of high mol. wt. DNA (40 to 100S) was found to be synthesized beginning approx. 13 h p.i. and continuing up to about 35 h p.i. DNA--DNA hybridization studies on this newly synthesized DNA showed it to be cellular DNA. When this material was density labelled with 5-bromodeoxyuridine and centrifuged to equilibrium through alkaline CsCl gradients, it was found to be the product of semi-conservation replication and not of repair synthesis.