Mutant sigma factor blocks transition between promoter binding and initiation of transcription.
The sigma subunit of bacterial RNA polymerase is required for specific binding of the enzyme to promoters. This specificity is probably directed by two regions of most sigma factors that make sequence-specific contacts at two regions of promoters, the -10 and -35 regions. We found that a single amino acid substitution in the -10 recognition region of sigma E from Bacillus subtilis trapped RNA polymerase in a stable complex with promoter DNA in which it was unable to initiate transcription. Our results are consistent with the view that promoter utilization by RNA polymerase proceeds through several intermediate steps and suggest that the -10 recognition region of sigma factors may participate in a step that follows initial promoter binding.
Jones
C H
CH
Department of Microbiology and Immunology, Emory University School of Medicine, Atlanta, GA 30322.
Moran
C P
CP
D000595:Amino Acid Sequence; D001412:Bacillus subtilis / Q000201:enzymology; D001665:Binding Sites; D004252:DNA Mutational Analysis; D012321:DNA-Directed RNA Polymerases / Q000378:metabolism*; D005798:Genes, Bacterial; D066298:In Vitro Techniques; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D012045:Regulatory Sequences, Nucleic Acid; D016415:Sequence Alignment; D012808:Sigma Factor / Q000235:genetics*; D013171:Spores, Bacterial; D013329:Structure-Activity Relationship; D014158:Transcription, Genetic
D012808:Sigma Factor; D012321:DNA-Directed RNA Polymerases