Previous Article | Next Article ![]()
J. Bacteriol., 05 1996, 2742-2748, Vol 178, No. 10
J Garcia-Lara, LH Shang and LI Rothfield
The sdiA gene codes for a protein that regulates expression of the ftsQAZ
cluster of essential cell division genes of Escherichia coli. SdiA
up-regulates the ftsQ2p promoter that initiates transcription into the
ftsQAZ cluster. In this paper, we report that expression of sdiA is itself
regulated by a factor that is released into the growth medium by E. coli.
When medium that had previously supported growth of E. coli (conditioned
medium) was used to support growth of an indicator E. coli strain that
contained an sdiA-lacZ transcriptional reporter, there was a 50 to 80%
decrease in sdiA expression as monitored by beta- galactosidase activity.
The down-regulation of PsdiA was associated with a decrease in expression
of the SdiA target promoter ftsQ2p, as monitored by expression of an
ftsQ2p-lacZ transcriptional fusion. An effect of conditioned medium on
ftsQ2p expression was not seen when the wild-type sdiA gene was disrupted
by insertional mutagenesis, indicating that the effect on ftsQ2p expression
was secondary to the down-regulation of PsdiA. Conditioned medium had no
effect on expression of Plac, PrpoS, or several other promoters associated
with the ftsQAZ gene cluster (ftsQ1p and ftsZ1-4p). This suggests that the
response is specific for PsdiA and for promoters that are regulated by the
sdiA gene product and that cell-to-cell signalling may play a role in
regulating expression of this group of genes.
Copyright © 1996, American Society for Microbiology
An extracellular factor regulates expression of sdiA, a transcriptional activator of cell division genes in Escherichia coli
Department of Microbiology, University of Connecticut Health Center, Farmington 06030-3205, USA.
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 |