Dataset Information

T-POP array identifies EcnR and PefI-SrgD as novel regulators of flagellar gene expression.

ABSTRACT: The T-POP transposon was employed in a general screen for tetracycline (Tet)-induced chromosomal loci that exhibited Tet-activated or Tet-repressed expression of a fliC-lac transcriptional fusion. Insertions that activated flagellar transcription were located in flagellar genes. T-POP insertions that exhibited Tet-dependent fliC-lac inhibition were isolated upstream of the ecnR, fimZ, pefI-srgD, rcsB, and ydiV genes and in the flagellar gene flgA, which is located upstream of the anti-sigma(28) factor gene flgM. When expressed from the chromosomal P(araBAD) promoter, EcnR, FimZ, PefI-SrgD, and RcsB inhibited the transcription of the flagellar class 1 flhDC operon. YdiV, which is weakly homologous to EAL domain proteins involved in cyclic-di-GMP regulation, appears to act at a step after class 1 transcription. By using a series of deletions of the regulatory genes to try to disrupt each pathway, these regulators were found to act largely independently of one another. These results identify EcnR and PefI-SrgD as additional components of the complex regulatory network controlling flagellar expression.

SUBMITTER: Wozniak CE

PROVIDER: S-EPMC2648201 | biostudies-literature | 2009 Mar

REPOSITORIES: biostudies-literature

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T-POP array identifies EcnR and PefI-SrgD as novel regulators of flagellar gene expression.

Wozniak Christopher E CE Lee Changhan C Hughes Kelly T KT

Journal of bacteriology 20081229 5

The T-POP transposon was employed in a general screen for tetracycline (Tet)-induced chromosomal loci that exhibited Tet-activated or Tet-repressed expression of a fliC-lac transcriptional fusion. Insertions that activated flagellar transcription were located in flagellar genes. T-POP insertions that exhibited Tet-dependent fliC-lac inhibition were isolated upstream of the ecnR, fimZ, pefI-srgD, rcsB, and ydiV genes and in the flagellar gene flgA, which is located upstream of the anti-sigma(28) ...[more]

PMID: 19114490

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Dataset Information

T-POP array identifies EcnR and PefI-SrgD as novel regulators of flagellar gene expression.

Publications

T-POP array identifies EcnR and PefI-SrgD as novel regulators of flagellar gene expression.

Similar Datasets

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