Insights into the Mechanisms of Basal Coordination of Transcription Using a Genome-Reduced Bacterium

We have profiled the transcriptome of the model organism Mycoplasma pneumoniae across 115 growth conditions and results suggest that the basal coordination of transcription is mediated by the physical entities and mechanical properties of the transcription process itself, and that operon-like behaviors may strongly vary from condition to condition. In the paper three qualitatively different levels of co-expression corresponding to distinct relative orientations and intergenic properties of adjacent genes have been identified. In that sense, transcription of adjacent genes and operons is specifically repressed by DNA regions preferentially bound by RNA polymerases, by intrinsic terminators, and by large intergenic distances.