“…A 5 kb HindIII fragment was subcloned (pEV1), and DNA sequence analysis was performed by dideoxynucleotide chain termination method (Sanger et al, 1977). A 586 bp segment representing the core elements of the P1 promoter (Liptay et al, 1994;Lombardi et al, 1995) was ampli®ed by PCR using a 5' oligonucleotide primer beginning at 7586 bp with respect to the major P1 start site and containing a HindIII restriction enzyme site, with the sequence: 5'-CCCAAGCTTTCCCGGAGCCTTGAGGCT-GA-3'; and a 3' oligonucleotide primer extending from the +70 bp position of the P1 promoter, containing and XbaI restriction enzyme site, and having the sequence: 5'-CGTCTAGAGCTAAAGGCCCTCCTCCCTC-3'. The ampli®ed DNA was ligated to the HindIII and XbaI sites upstream of the CAT (chloramphenicol acetyl transferase) reporter gene in the pCAT vector (Promega) to construct P1 CAT.…”