Types | DnaRegion
|
Roles | Regulatory
promoter
|
Sequences | BBa_K264002_sequence (Version 1)
|
Description
The UP element is a component of the promoter located upstream of the -35 region. Though not necessary for transcription, the UP element increases the rate of transcription initiation by interacting with the alpha-subunit of RNA polymerase. A consensus sequence, -59 nnAAA(A/T)(A/T)T(A/T)TTTTnnAAAAnnn -38, was derived from a collection of many UP elements based on nucleotide frequency at each position (Estrem et al., 1998). UP Element Design 1 is the UP element with the highest transcription rate increase reported in that study. Design 1 was systematically modified (BBa_K264001-K264007) to vary the relative strength of its effect based on the hypothesis that the most significant promoter enhancement would occur when the UP element sequence used the most frequently-occurring nucleotides at each position (i.e., the consensus sequence). A spacer, CT, is placed between the UP element and subsequent promoters to maintain proper alignment with RNAP.
Notes
The observed UP elements were A-T rich. Therefore, the rational sequence modifications of Design 1 were made to preserve this feature. Nucleotides in Design 1 at positions -59, -54, and -45 were changed from G to T, A to T, and C to G, respectively. A spacer, CT, is placed between the UP element and subsequent promoters to maintain proper alignment with RNAP.
Source
Rational redesign of BBa_K264000