Fate of Frog Virus 3 DNA Replicated in the Nucleus of Arginine-deprived CHO Cells

Abstract

In a productive infection, frog virus 3 (FV 3) DNA was synthesized in both the cell nucleus and cytoplasm. The infection was aborted in arginine-starved Chinese hamster ovary cells and viral DNA replication was then restricted to the nuclear compartment. The newly synthesized FV3 DNA present in the nucleus was of genomic size. After the addition of arginine, this DNA was transferred into the cytoplasm and could be encapsidated. The formation of infectious particles occurred even if an inhibitor of DNA synthesis was added simultaneously with arginine. Although the synthesis of early FV3 polypeptides and their intracellular distribution were comparable in the presence or in the absence of arginine, the production of late species was greatly reduced by arginine deprivation; one of these late proteins must be involved in the passage from the nuclear to the cytoplasmic phase of FV3 DNA replication. This system made it possible to carry out an independent analysis of the nuclear events that comprise the 1st stage of FV3 multiplication.