title: Restricted replication of ectromelia virus in cell culture correlates with mutations in virus-encoded host range gene.
abstract: Ectromelia virus (strain Moscow) was shown to replicate poorly or not at all in cell lines derived from the rabbit or hamster. The failure of ectromelia virus to replicate in cell lines derived from the hamster suggested that the virus lacked a functional CHO host range (hr) gene required for multiplication in these cells. A DNA fragment which hybridized to the CHO hr gene was cloned from the ectromelia virus genome and shown by sequence analysis to be deleted of 506 bp within the ectromelia virus CHO hr homologue. Two additional ectromelia viruses (Hampstead and Mill Hill strains) were also shown to lack an intact CHO hr gene. Insertion of the CHO gene from cowpox virus into the ectromelia virus genome extended the host range of ectromelia virus in tissue culture. These results demonstrate that an intact CHO hr gene is not required for maintenance of ectromelia virus in nature and provide a partial explanation for ectromelia virus' narrow host range, as opposed to the broad host range of cowpox virus, which has a functional CHO hr gene.
authors.affiliation: Laboratory of Viral Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892.
authors.forename: W
authors.initials: W
authors.lastname: Chen
authors.forename: R
authors.initials: R
authors.lastname: Drillien
authors.forename: D
authors.initials: D
authors.lastname: Spehner
authors.forename: R M
authors.initials: RM
authors.lastname: Buller
mesh_terms: D000818:Animals; D001483:Base Sequence; D015139:Blotting, Southern; D016466:CHO Cells; D002478:Cells, Cultured; D003001:Cloning, Molecular; D006224:Cricetinae; D004279:DNA, Viral / Q000235:genetics; D004481:Ectromelia virus / Q000254:growth & development*; D005814:Genes, Viral; D051379:Mice; D008969:Molecular Sequence Data; D015183:Restriction Mapping; D016415:Sequence Alignment; D013045:Species Specificity; D014616:Vaccinia virus / Q000235:genetics; D015678:Viral Structural Proteins / Q000235:genetics; D014779:Virus Replication
chemical_list: D004279:DNA, Viral; D015678:Viral Structural Proteins