Proximity of TTTGTC motifs to Fep1p binding sites in the fip1 promoter. The 500 base pair (bp) region upstream of the fip1 open reading frame contains three TTTGTC motifs (closed rectangles)  and two Fep1p binding sites (open rectangles) . A third Fep1p binding motif is found further upstream, but its role in Fep1p mediated regulation is unknown. Horizontal arrows indicate the 271 bp promoter fragment used previously  to study the effects of mutations in two of the TTTGTC motifs (asterisks). The area encompassing the two known Fep1p binding sites and the most distal mutated TTTGTC motif is shown enlarged to illustrate their proximity. Sequence residues that are conserved between the fip1 and frp1 promoters are shaded gray . The vertical separator indicates the 3' end of the 271 bp promoter fragment.