Previous Article | Next Article ![]()
J. Bacteriol., Aug 1995, 4676-4680, Vol 177, No. 16
R Lange, D Fischer and R Hengge-Aronis
rpoS is the structural gene for the sigma S subunit of RNA polymerase which
controls the expression of a large number of genes in Escherichia coli that
are induced during entry into stationary phase or in response to increased
medium osmolarity. Using a combination of primer extension experiments and
a 5' deletion analysis of the region upstream of rpoS, we show that rpoS
transcription is mainly driven by a single promoter (rpoSp1) located within
the nlpD gene upstream of rpoS (the two relatively weak nlpD promoters
contribute to the low level of rpoS expression during early exponential
phase). In addition, we demonstrate that the expression of both
transcriptional and translational rpoS::lacZ fusions as well as the level
of rpoS mRNA originating at rpoSp1 is strongly reduced in ppGpp-deficient
relA spoT mutants. However, experiments with the 5' deletion constructs
indicate that a lack of ppGpp does affect transcriptional elongation rather
than initiation.
Copyright © 1995, American Society for Microbiology
Identification of transcriptional start sites and the role of ppGpp in the expression of rpoS, the structural gene for the sigma S subunit of RNA polymerase in Escherichia coli
Department of Biology, University of Constance, Germany.
This article has been cited by other articles:
| Appl. Environ. Microbiol. | Infect. Immun. | Eukaryot. Cell |
|---|---|---|
| Mol. Cell. Biol. | J. Virol. | Microbiol. Mol. Biol. Rev. |
| ALL ASM JOURNALS |