Factors Affecting Start Site Selection at the Escherichia coli fis Promoter
AUTOR(ES)
Walker, Kimberly A.
FONTE
American Society for Microbiology
RESUMO
Transcription initiation with CTP is an uncommon feature among Escherichia coli σ70 promoters. The fis promoter (fis P), which is subject to growth phase-dependent regulation, is among the few that predominantly initiate transcription with CTP. Mutations in this promoter that cause a switch from utilization of CTP to either ATP or GTP as the initiation nucleotide drastically alter its growth phase regulation pattern, suggesting that the choice of the primary initiating nucleotide can significantly affect its regulation. To better understand what factors influence this choice in fis P, we made use of a series of promoter mutations that altered the nucleotide or position used for initiation. Examination of these promoters indicates that start site selection is determined by a combination of factors that include preference for a nucleotide distance from the −10 region (8 > 7 > 9 ≫ 6 ≫ 10 > 11), initiation nucleotide preference (A = G ≫ CTP ≥ UTP), the DNA sequence surrounding the initiation region, the position of the −35 region, and changes in the intracellular nucleoside triphosphate pools. We describe the effects that each of these factors has on start site selection in the fis P and discuss the interplay between position and nucleotide preference in this important process.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=135273Documentos Relacionados
- Effects of transcriptional start site sequence and position on nucleotide-sensitive selection of alternative start sites at the pyrC promoter in Escherichia coli.
- Start site selection at lacUV5 promoter affected by the sequence context around the initiation sites.
- Deletion analysis of the fis promoter region in Escherichia coli: antagonistic effects of integration host factor and Fis.
- Factors affecting authentic 5' splice site selection in plant nuclei.
- The yeast PHO5 promoter: phosphate-control elements and sequences mediating mRNA start-site selection.