title: Vaccinia virus infection of HeLa cells. I. Synthesis of vaccinia DNA in host cell nuclei.
abstract: The replication of vaccinia virus is thought to take place exclusively in the cytoplasm of host cells. However, using DNA-DNA hybridization techniques, it can be shown that a significant fraction of the synthesis of vaccinia DNA takes place in the nucleus as well as the cytoplasm. The (3H) thymiding pulse-labeled vaccinia DNA synthesized in the nucleus reaches a maximum at about 3 h after infection, corresponding to the time of maximal DNA synthesis in infected cells. At this time host DNA synthesis drops to about 25% of the rate of the uninfected cells. Even with short labeling times (2 min) the nucleus is found to contain 60% of the incorporated (3H)thymidine, much of which is in vaccinia DNA. Prior inhibition of host nuclear DNA synthesis with mitomycin C, followed by removal of the antibiotic causes a subsequent inhibition of vaccinia DNA synthesis and complete suppression of mature virus. Purified nuclei, isolated from vaccinia-infected cells, also synthesize vaccinia DNA in vitro. Over 90% of the DNA synthesized in vitro by isolated nuclei contain vaccinia-specific sequences.
mesh_terms: D002458:Cell Fractionation; D002467:Cell Nucleus / Q000378:metabolism*; D002474:Cell-Free System; D003593:Cytoplasm / Q000378:metabolism / Q000382:microbiology; D004261:DNA Replication; D004273:DNA, Neoplasm / Q000096:biosynthesis; D004279:DNA, Viral / Q000096:biosynthesis*; D005260:Female; D005467:Floxuridine / Q000494:pharmacology; D006367:HeLa Cells; D006801:Humans; D008937:Mitomycins / Q000494:pharmacology; D009693:Nucleic Acid Hybridization; D013936:Thymidine / Q000378:metabolism; D014316:Tritium; D014616:Vaccinia virus / Q000254:growth & development / Q000378:metabolism*; D014779:Virus Replication
chemical_list: D004273:DNA, Neoplasm; D004279:DNA, Viral; D008937:Mitomycins; D005467:Floxuridine; D014316:Tritium; D013936:Thymidine