Cloning of Herpesvirus saimiri DNA fragments representing the entire L-region of the genome.

Purified particles of Herpesvirus saimiri, a potent tumor-eliciting virus of primates, contain genomic DNA molecules (145-170 kb) consisting of a unique L-DNA region (112 kb) which is flanked by variable stretches of repetitive sequences (H-DNA). Restriction fragments representing the entire L-DNA of H. saimiri strain No. 11 were cloned in plasmid and bacteriophage vectors. The internal fragments of L-DNA generated by the enzymes EcoRI and KpnI were inserted into plasmid pACYC184, cosmid pJC81, or bacteriophage lambda derivative Charon 4A. The terminal parts of L-DNA, including the junctions between repetitive DNA and unique sequences, were cloned between the cleavage sites for KpnI and SmaI in the plasmid vector pWD7, which was constructed for this purpose. Molecular cloning allowed us to confirm and modify, in part, the existing cleavage maps of H. saimiri DNA. It provides a basis for future studies on virus replication and oncogenic transformation.