Evidence that the human cytomegalovirus 46-kDa UL72 protein is not an active dUTPase but a late protein dispensable for replication in fibroblasts.
The Human Cytomegalovirus (HCMV) UL72 gene is considered to be the equivalent of the dUTPase gene of the Alpha- and Gamma-herpesviruses. To characterize its function, the expression profiles of UL72 at both the RNA and the protein level were determined. The gene is expressed with a late kinetics and the corresponding UL72 46-kDa protein accumulates late during infection in the cytoplasm of infected cells. The pUL72 was expressed in E. coli and the purified recombinant protein did not display a detectable dUTPase activity. The viral yields of reconstituted HCMV RVDeltaUL72 viruses carrying a deletion within the UL72 ORF demonstrated a moderate growth defect following low MOI infections, whereas their DNA synthesis profiles were not significantly different from those of the parental HCMV RVAD169. These results demonstrate that the UL72 gene product is not a dUTPase and is not essential for replication in human fibroblasts.
Caposio
Patrizia
P
Department of Public Health and Microbiology, University of Torino, 9-10126 Turin, Italy.
Riera
Ludovica
L
Hahn
Gabriele
G
Landolfo
Santo
S
Gribaudo
Giorgio
G
D000595:Amino Acid Sequence; D001483:Base Sequence; D002478:Cells, Cultured; D003587:Cytomegalovirus / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology*; D017931:DNA Primers / Q000235:genetics; D004279:DNA, Viral / Q000235:genetics; D005347:Fibroblasts / Q000821:virology; D015870:Gene Expression; D005814:Genes, Viral; D006801:Humans; D008969:Molecular Sequence Data; D008970:Molecular Weight; D016297:Mutagenesis, Site-Directed; D011755:Pyrophosphatases / Q000737:chemistry / Q000235:genetics / Q000502:physiology; D017386:Sequence Homology, Amino Acid; D014764:Viral Proteins / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D014779:Virus Replication
D017931:DNA Primers; D004279:DNA, Viral; D014764:Viral Proteins; D011755:Pyrophosphatases; C020020:dUTP pyrophosphatase