A RANDOM DNA-SEQUENCING, COMPUTER-BASED APPROACH FOR THE GENERATION OF A GENE MAP OF MOLLUSCUM CONTAGIOSUM VIRUS

The genome of Molluscum contagiosum virus (MCV) has a high G + C conte nt, which largely differs from those of vaccinia virus (VAC) and other characterized poxviruses. This has precluded the use of DNA hybridiza tion for the identification of MCV genes and the further establishment of the virus genetic map. To circumvent this problem, we have partial ly sequenced clones containing virus restriction endonuclease fragment s, which were derived by either single or double-digestion of genomic DNA from the subtype I of MCV. The DNA sequences were translated and u sed to search protein data bases. This analysis resulted in the findin g of high-scoring matches to data base entries, including forty-five V AC genes. In addition, MCV-specific sequences that encoded protein dom ains of known function (i.e. DNA J domain) were found. The locations o f MCV clones were inferred from the presumed colinearity of both MCV a nd VAC genomes, and further confirmed by PCR technology. The data pres ented here led to the construction of a partial genetic map of MCVI, w hich revealed that the order and orientation of a large number of MCV genes were equivalent to those of their VAC homologues. The conserved gene arrangement was apparently disrupted in the terminal regions, whe re MCV sequences showing homologies with the VAC counterparts were not found.