Open AccessDifferent thermal energy requirement for open complex formation byEscherichia coliRNA polymerase at two related promoters
Author(s) -
Eileen A. Grimes,
Stephen J. W. Busby,
Stephen Minchin
Publication year - 1991
Publication title -
nucleic acids research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 9.008
H-Index - 537
eISSN - 1362-4954
pISSN - 0305-1048
DOI - 10.1093/nar/19.22.6113
Subject(s) - promoter , biology , rna polymerase , random hexamer , transcription (linguistics) , rna polymerase ii , consensus sequence , genetics , microbiology and biotechnology , rna , dna , gene , gene expression , base sequence , linguistics , philosophy
We have studied the effect of temperature on transcription initiation in vitro at two related promoters ga/Pcon and ga/P1, which have the same nucleotide sequence around the -10 region and transcription start site, but differ in upstream sequences. One of the promoters, ga/Pcon, carries the consensus -35 hexamer, 5'TTGACA 3', whilst ga/P1 contains a block of 'distortable' upstream sequences that allow promoter function in the absence of a -35 region consensus sequence. RNA polymerase can form complexes with both promoters at a range of temperatures. However, the thermal energy requirement for open complex formation differs: open complexes can form at ga/P1 at low temperatures, whereas ga/Pcon requires higher temperatures. The thermal energy requirement for transcription from preformed open complexes is the same for both promoters.