FIG. 7.

Gel retardation analysis. To locate the ORF 50 response elements contained within the ORF 57 gene promoter, gel retardation assays were performed on oligonucleotides mapping to this region. (a) Set 1: untransfected cells (lane 1) and pORF50a-transfected cells (lane 2); set 2: untransfected cells (lane 3) and pORF50a-transfected cells (lane 4). (b) Gel retardation experiments were repeated in the presence of increased amounts of unlabelled set 1 oligonucleotides. The retarded complexes were separated on a 5% polyacrylamide gel, run in 1% Tris-borate-EDTA buffer, and detected by autoradiography.