FIGURE 5.

Luciferase reporter gene assays. A, diagram of ovine core promoter as used in transfection experiments. GA, putative GATA-1 factor binding site; H1 and H2, heat shock element motifs; M1, M2, M3, and M4, conserved motifs as defined in Westaway et al., (14); M4v, variants of M4 motifs; AP1, AP2, and SP1, putative binding sites for transcription factors AP1, AP2, and SP1. B, four plasmid constructs containing the PrP gene promoter intact or with mutations in either motif 1 (YY1 binding site) or motif 2 (E4BP4 binding site) in front of the luciferase open reading frame were used to transfect N2a neuroblastoma cells. C, mean relative luciferase activity and S.D. from three experiments are shown. Columns on the right site of the diagram indicate the presence or absence of the binding sequences for YY1 and E4BP4, respectively.