FIG. 1.

Construction of recombinant wild-type and mutant CMV. The CMV genome containing unique long (U_L) and unique short (U_S) regions flanked by repeats (ab, b′ a′c′, and ca) is depicted (top) along with the approximate positions of the cosmid fragments used in construction of the recombinant viruses (middle). The ∼9.6 kb SacI/BamHI insert present in pEQ694 (bottom) contains the UL4 gene and flanking regions. Relevant restriction sites are indicated. The pEQ694 sequence corresponding to the 5′ end of the UL4 mRNA contains a BglII linker insertion (bold) into a NaeI site and a mutation of the uORF2 AUG codon to AAG (underlined).