Strain-dependent differences in the human cytomegalovirus replication origin.
The nucleotide sequence of the human cytomegalovirus replication origin of strain Towne (an AatII-SacI fragment corresponding to nt 90372-94637 of strain AD169) was determined and compared with AD169. Two differences were found in the nucleotide sequence level. One was the alteration of structural organization (a major difference): a 189-bp region of AD169 (nt 93337-93525) was directly repeated three times in Towne. The other was a change in the nucleotide residue level including substitution, insertion, or deletion (a minor difference). The divergent residues were predominantly localized within the nt 92591-92855 region of AD169. A replication assay revealed that replication ability remained after deletion of the 189-bp repeat but disappeared after either a 1.5-kb deletion from the AatII end or a 0.9-kb deletion from the SacI end. The 1.5- and 0.9-kb regions were relatively conserved. These results indicate that at least two regions essential for replication ability lie outside of both the relatively variable region and the 189-bp repeat and suggest that these essential regions support replication even with a spatial separation of either one (AD169) or three repeats (Towne) of the 189-bp region.
Chen
Z
Z
Department of Virology, The Institute of Medical Science, The University of Tokyo, Japan.
Watanabe
S
S
Yamaguchi
N
N
D001483:Base Sequence; D015139:Blotting, Southern; D002460:Cell Line; D003587:Cytomegalovirus / Q000235:genetics*; D004279:DNA, Viral / Q000737:chemistry / Q000302:isolation & purification; D004622:Embryo, Mammalian; D016679:Genome, Viral; D006801:Humans; D008168:Lung; D008969:Molecular Sequence Data; D018741:Replication Origin; D015183:Restriction Mapping; D012689:Sequence Homology, Nucleic Acid; D013045:Species Specificity
D004279:DNA, Viral