Consequences of mutations in the upstream promoter region
The effect of a
point mutation at each position can be measured by
comparing the level of mRNA transcription relative to
the un-mutated gene [vertical scale]. The graph shows strong reduction of transcription
level 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 large majority of mutations in this region have no measurable effect on transcription. Dots indicate positions where the consequences of mutations are unknown.