TY - JOUR
T1 - Factors influencing preferential utilization of RNA polymerase containing sigma-38 in stationary-phase gene expression in Escherichia coli
AU - Eun, Young Kim
AU - Shin, Min Sang
AU - Joon, Haeng Rhee
AU - Choy, Hyon E.
PY - 2004/6
Y1 - 2004/6
N2 - In order to understand the molecular basis of selective expression of stationary-phase genes by RNA polymerase containing σ38 (Eσ38) in Escherichia coli, we examined transcription from the stationary-phase promoters, katEP, bolAP, hdeABP, csgBAP, and mcbP, in vivo and in vitro. Although these promoters are preferentially recognized in vivo by Eσ38, they are transcribed in vitro by both Eσ38 and Eσ70 containing the major exponential σ, σ70. In the presence of high concentrations of glutamate salts, however, only Eσ38 was able to efficiently transcribe from these promoters, which supports the concept that the promoter selectivity of σ38-containing RNA polymerase is observed only under specific reaction conditions. The examination of 6S RNA, which is encoded by the ssr1 gene in vivo, showed that it reduced Eσ70 activity during the stationary phase, but this reduction of activity did not result in the elevation of Eσ38 activity. Thus, the preferential expression of stationary-phase genes by Eσ38 is unlikely the consequence of selective inhibition of Eσ70 by 6S RNA.
AB - In order to understand the molecular basis of selective expression of stationary-phase genes by RNA polymerase containing σ38 (Eσ38) in Escherichia coli, we examined transcription from the stationary-phase promoters, katEP, bolAP, hdeABP, csgBAP, and mcbP, in vivo and in vitro. Although these promoters are preferentially recognized in vivo by Eσ38, they are transcribed in vitro by both Eσ38 and Eσ70 containing the major exponential σ, σ70. In the presence of high concentrations of glutamate salts, however, only Eσ38 was able to efficiently transcribe from these promoters, which supports the concept that the promoter selectivity of σ38-containing RNA polymerase is observed only under specific reaction conditions. The examination of 6S RNA, which is encoded by the ssr1 gene in vivo, showed that it reduced Eσ70 activity during the stationary phase, but this reduction of activity did not result in the elevation of Eσ38 activity. Thus, the preferential expression of stationary-phase genes by Eσ38 is unlikely the consequence of selective inhibition of Eσ70 by 6S RNA.
KW - 6S RNA
KW - in vitro transcription
KW - RNA polymerase
KW - Sigma factor
UR - http://www.scopus.com/inward/record.url?scp=3242697144&partnerID=8YFLogxK
M3 - Article
C2 - 15357303
AN - SCOPUS:3242697144
SN - 1225-8873
VL - 42
SP - 103
EP - 110
JO - Journal of Microbiology
JF - Journal of Microbiology
IS - 2
ER -