Cellular DNA Synthesis in Productively-Infected Cells

Inhibition of Cellular DNA Synthesis in Productively-Infected Cells 

The best known response of cellular DNA synthesis to adenovirus infection must be the inhibition typically seen when permissive human cells are infected. In growing cells, cellular DNA synthesis is inhibited by more than 50% by 6-8 hr and completely by 10-13 hr after an adenovirus infection (Ginsberg et al., 1967), concomitant with the initiation and acceleration of viral DNA synthesis. Unfortunately, very few studies have concentrated on elucidation of this inhibitory process. Hodge and Scharff (1969) presented some evidence to suggest that initiation of new rounds of cellular DNA synthesis was prevented by adenovirus infection. Thus, when synchronized human cells were infected at a time in their cell cycle that placed viral DNA replication in the G1 phase, neither premature, nor normal S phase, initiation of cellular DNA synthesis were observed. Alternatively, infection to place initiation of viral DNA synthesis after the onset of the host cells S phase permitted completion of those rounds of cellular DNA synthesis begun before the inhibitory mechanism exerted 

It seems quite clear that cellular factors participate in later steps in adenoviral DNA synthesis, for the in vitro systems that permit complete and faithful replication of a viral DNA-terminal protein template are dependent on them (Nagata et ai, 1983). Thus, competition for a cellular protein that functions beyond initiation also remains a real possibility. Unfortunately, the detailed examinations of the properties of cellular DNA made as the inhibitory effects of an adenovirus infection take hold, which are necessary to assess such an hypothesis, have not been performed. In the one study of this kind reported. Pater 

Our understanding of the mechanism(s) whereby adenovirus infection of growing, permissive cells inhibits replication of cellular 

As the H5hrl mutation, like deletions within ElA, also prevents the expression of other early genes (Berk et al., 1979 Jones and 

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