Consequences of mutations in the upstream promoter region

    The effect of a mutation at each position can be measured by comparing the level of mRNA transcription relative to the unmutated gene [Vertical scale]. The graph shows strong reduction of transcription by mutations in the promoter regions at -10 (ATATAA) & -35 (GGCCAATC), and at an upstream enhancer region. Note that mutations at two sites immediately 5' to the -35 promoter sharply increase transcription. A mutation at the start point of transcription () turns off transcription entirely. 

    Note that the majority of mutations in this region have no measurable affect on transcription. Dots indicate positions where the consequences of mutations are unknown.