Types | DnaRegion
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Roles | promoter
Regulatory
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Sequences | BBa_K264003_sequence (Version 1)
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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, -58, -54, and -45 were changed from G to A, G to A, 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