title: Development of a quantitative gene expression assay for Chlamydia trachomatis identified temporal expression of sigma factors.
abstract: Chlamydia trachomatis is an important human pathogen which possesses a unique bi-phasic developmental cycle. We used lightcycler methodology to quantitatively measure gene transcript levels in C. trachomatis strain L2. By measuring 16S rRNA transcript levels, we determined C. trachomatis L2 to have a generation time of approximately 3 h and an inclusion burst size of 200-300 particles. The three chlamydial sigma factor genes rpoD (sigma66), rpsD (sigma28) and rpoN (sigma54) exhibited different patterns of temporal expression. rpoD was central to early chlamydial development, whereas rpsD and rpoN were temporally expressed, coinciding with elementary body (EB) to reticulate body (RB) conversion and RB to EB conversion, respectively.
authors.affiliation: School of Life Sciences, Queensland University of Technology, Brisbane, Australia. s.mathews@qut.edu.au
authors.forename: S A
authors.initials: SA
authors.lastname: Mathews
authors.forename: K M
authors.initials: KM
authors.lastname: Volp
authors.forename: P
authors.initials: P
authors.lastname: Timms
mesh_terms: D002460:Cell Line; D002692:Chlamydia trachomatis / Q000235:genetics* / Q000254:growth & development; D015342:DNA Probes; D004268:DNA-Binding Proteins; D012321:DNA-Directed RNA Polymerases / Q000032:analysis / Q000235:genetics; D005456:Fluorescent Dyes; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial; D006801:Humans; D016133:Polymerase Chain Reaction; D051877:RNA Polymerase Sigma 54; D012333:RNA, Messenger / Q000032:analysis*; D012336:RNA, Ribosomal, 16S / Q000032:analysis; D012808:Sigma Factor / Q000032:analysis / Q000235:genetics*; D013997:Time Factors
chemical_list: D015342:DNA Probes; D004268:DNA-Binding Proteins; D005456:Fluorescent Dyes; D012333:RNA, Messenger; D012336:RNA, Ribosomal, 16S; D012808:Sigma Factor; C081775:RNA polymerase sigma 70; D012321:DNA-Directed RNA Polymerases; D051877:RNA Polymerase Sigma 54