ChxR is a transcriptional activator in Chlamydia

Ingrid Chou Koo, Don Walthers, P. Scott Hefty, Linda Kenney, Richard S. Stephens

Research output: Contribution to journalArticle

25 Citations (Scopus)

Abstract

Chlamydia spp. are obligate intracellular bacterial pathogens that alternate between two metabolically and morphologically distinct developmental forms, and differentiation depends on transcriptional regulation. Genome sequencing of Chlamydia trachomatis revealed an ORF, CT630 (chxR), whose amino acid sequence contains a winged helix-turn-helix motif similar to the DNA-binding domain of response regulators in the OmpR subfamily. ChxR differs from many response regulators in that essential residues in the receiver or phosphorylation domain are lacking. ChxR functions as a transcriptional regulator because it activated transcription of ompF and ompC when expressed in Escherichia coli. In vitro transcription combined with microarray analysis also demonstrated that ChxR activates its own expression by binding directly to sites upstream of chxR; it also activates infA, tufA, oppA, and CT084. DNase I protection studies showed that ChxR bound to sites in the ompF and ompC promoter proximal regions that overlap but were distinct from OmpR binding sites. Both proteins could bind simultaneously to their nonoverlapping binding sites. This report identifies a stage-specific transcriptional regulator and some of its target genes in Chlamydia.

Original languageEnglish (US)
Pages (from-to)750-755
Number of pages6
JournalProceedings of the National Academy of Sciences of the United States of America
Volume103
Issue number3
DOIs
StatePublished - Jan 17 2006
Externally publishedYes

Fingerprint

Chlamydia
Helix-Turn-Helix Motifs
Binding Sites
Deoxyribonuclease I
Chlamydia trachomatis
Microarray Analysis
Genetic Promoter Regions
Open Reading Frames
Amino Acid Sequence
Phosphorylation
Genome
Escherichia coli
DNA
Genes
Proteins
In Vitro Techniques

Keywords

  • OmpR
  • Response regulator
  • Transcription
  • Winged helix-turn-helix protein

ASJC Scopus subject areas

  • Genetics
  • General

Cite this

ChxR is a transcriptional activator in Chlamydia. / Koo, Ingrid Chou; Walthers, Don; Hefty, P. Scott; Kenney, Linda; Stephens, Richard S.

In: Proceedings of the National Academy of Sciences of the United States of America, Vol. 103, No. 3, 17.01.2006, p. 750-755.

Research output: Contribution to journalArticle

Koo, Ingrid Chou ; Walthers, Don ; Hefty, P. Scott ; Kenney, Linda ; Stephens, Richard S. / ChxR is a transcriptional activator in Chlamydia. In: Proceedings of the National Academy of Sciences of the United States of America. 2006 ; Vol. 103, No. 3. pp. 750-755.
@article{15347a9f32db443da92b204516ade3ee,
title = "ChxR is a transcriptional activator in Chlamydia",
abstract = "Chlamydia spp. are obligate intracellular bacterial pathogens that alternate between two metabolically and morphologically distinct developmental forms, and differentiation depends on transcriptional regulation. Genome sequencing of Chlamydia trachomatis revealed an ORF, CT630 (chxR), whose amino acid sequence contains a winged helix-turn-helix motif similar to the DNA-binding domain of response regulators in the OmpR subfamily. ChxR differs from many response regulators in that essential residues in the receiver or phosphorylation domain are lacking. ChxR functions as a transcriptional regulator because it activated transcription of ompF and ompC when expressed in Escherichia coli. In vitro transcription combined with microarray analysis also demonstrated that ChxR activates its own expression by binding directly to sites upstream of chxR; it also activates infA, tufA, oppA, and CT084. DNase I protection studies showed that ChxR bound to sites in the ompF and ompC promoter proximal regions that overlap but were distinct from OmpR binding sites. Both proteins could bind simultaneously to their nonoverlapping binding sites. This report identifies a stage-specific transcriptional regulator and some of its target genes in Chlamydia.",
keywords = "OmpR, Response regulator, Transcription, Winged helix-turn-helix protein",
author = "Koo, {Ingrid Chou} and Don Walthers and Hefty, {P. Scott} and Linda Kenney and Stephens, {Richard S.}",
year = "2006",
month = "1",
day = "17",
doi = "10.1073/pnas.0509690103",
language = "English (US)",
volume = "103",
pages = "750--755",
journal = "Proceedings of the National Academy of Sciences of the United States of America",
issn = "0027-8424",
number = "3",

}

TY - JOUR

T1 - ChxR is a transcriptional activator in Chlamydia

AU - Koo, Ingrid Chou

AU - Walthers, Don

AU - Hefty, P. Scott

AU - Kenney, Linda

AU - Stephens, Richard S.

PY - 2006/1/17

Y1 - 2006/1/17

N2 - Chlamydia spp. are obligate intracellular bacterial pathogens that alternate between two metabolically and morphologically distinct developmental forms, and differentiation depends on transcriptional regulation. Genome sequencing of Chlamydia trachomatis revealed an ORF, CT630 (chxR), whose amino acid sequence contains a winged helix-turn-helix motif similar to the DNA-binding domain of response regulators in the OmpR subfamily. ChxR differs from many response regulators in that essential residues in the receiver or phosphorylation domain are lacking. ChxR functions as a transcriptional regulator because it activated transcription of ompF and ompC when expressed in Escherichia coli. In vitro transcription combined with microarray analysis also demonstrated that ChxR activates its own expression by binding directly to sites upstream of chxR; it also activates infA, tufA, oppA, and CT084. DNase I protection studies showed that ChxR bound to sites in the ompF and ompC promoter proximal regions that overlap but were distinct from OmpR binding sites. Both proteins could bind simultaneously to their nonoverlapping binding sites. This report identifies a stage-specific transcriptional regulator and some of its target genes in Chlamydia.

AB - Chlamydia spp. are obligate intracellular bacterial pathogens that alternate between two metabolically and morphologically distinct developmental forms, and differentiation depends on transcriptional regulation. Genome sequencing of Chlamydia trachomatis revealed an ORF, CT630 (chxR), whose amino acid sequence contains a winged helix-turn-helix motif similar to the DNA-binding domain of response regulators in the OmpR subfamily. ChxR differs from many response regulators in that essential residues in the receiver or phosphorylation domain are lacking. ChxR functions as a transcriptional regulator because it activated transcription of ompF and ompC when expressed in Escherichia coli. In vitro transcription combined with microarray analysis also demonstrated that ChxR activates its own expression by binding directly to sites upstream of chxR; it also activates infA, tufA, oppA, and CT084. DNase I protection studies showed that ChxR bound to sites in the ompF and ompC promoter proximal regions that overlap but were distinct from OmpR binding sites. Both proteins could bind simultaneously to their nonoverlapping binding sites. This report identifies a stage-specific transcriptional regulator and some of its target genes in Chlamydia.

KW - OmpR

KW - Response regulator

KW - Transcription

KW - Winged helix-turn-helix protein

UR - http://www.scopus.com/inward/record.url?scp=31444431578&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=31444431578&partnerID=8YFLogxK

U2 - 10.1073/pnas.0509690103

DO - 10.1073/pnas.0509690103

M3 - Article

C2 - 16407127

AN - SCOPUS:31444431578

VL - 103

SP - 750

EP - 755

JO - Proceedings of the National Academy of Sciences of the United States of America

JF - Proceedings of the National Academy of Sciences of the United States of America

SN - 0027-8424

IS - 3

ER -