TY - JOUR
T1 - RpoS-dependent transcriptional control of sprE
T2 - Regulatory feedback loop
AU - Ruiz, N.
AU - Peterson, C. N.
AU - Silhavy, T. J.
PY - 2001
Y1 - 2001
N2 - The stationary-phase response exhibited by Escherichia coli upon nutrient starvation is mainly induced by a decrease of the ClpXP-dependent degradation of the alternate primary σ factor RpoS. Although it is known that the specific regulation of this proteolysis is exercised by the orphan response regulator SprE, it remains unclear how SprE's activity is regulated in vivo. Previous studies have demonstrated that the cellular content of SprE itself is paradoxically increased in stationary-phase cells in an RpoS-dependent fashion. We show here that this RpoS-dependent upregulation of SprE levels is due to increased transcription. Furthermore, we demonstrate that sprE is part of the two-gene rssA-sprE operon, but it can also be transcribed from an additional RpoS-dependent promoter located in the rssA-sprE intergenic region. In addition, by using an in-frame deletion in rssA we found that RssA does not regulate either SprE or RpoS under the conditions tested.
AB - The stationary-phase response exhibited by Escherichia coli upon nutrient starvation is mainly induced by a decrease of the ClpXP-dependent degradation of the alternate primary σ factor RpoS. Although it is known that the specific regulation of this proteolysis is exercised by the orphan response regulator SprE, it remains unclear how SprE's activity is regulated in vivo. Previous studies have demonstrated that the cellular content of SprE itself is paradoxically increased in stationary-phase cells in an RpoS-dependent fashion. We show here that this RpoS-dependent upregulation of SprE levels is due to increased transcription. Furthermore, we demonstrate that sprE is part of the two-gene rssA-sprE operon, but it can also be transcribed from an additional RpoS-dependent promoter located in the rssA-sprE intergenic region. In addition, by using an in-frame deletion in rssA we found that RssA does not regulate either SprE or RpoS under the conditions tested.
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U2 - 10.1128/JB.183.20.5974-5981.2001
DO - 10.1128/JB.183.20.5974-5981.2001
M3 - Article
C2 - 11566997
AN - SCOPUS:0034815673
SN - 0021-9193
VL - 183
SP - 5974
EP - 5981
JO - Journal of bacteriology
JF - Journal of bacteriology
IS - 20
ER -