An Integrated Approach to Reconstructing Genome-scale Transcriptional Regulatory Networks [Affymetrix]

Rhodobacter sphaeroides is the best studied photosynthetic bacterium, yet much remains unknown about its transcriptional regulatory processes on a genome-scale. We developed a work-flow for genome-scale reconstruction of transcriptional regulatory networks and applied it to sequence and gene expression data sets available for R. sphaeroides. To assess the predictive performance of our reconstructed model, we generated global transcript level and/or protein-DNA interaction data for 3 transcription factors (PpsR, RSP_0489 and RSP_3341). This dataset contains global transcript level analyses for RSP_0489 and RSP_3341 deletion strains, as well as matching wild type controls. Microarray analysis conducted for deletion strains of 2 previously uncharacterized transcription factors predicted to be involved in the regulation of carbon metabolism and iron homeostasis in R. sphaeroides using the R. sphaeroides Affymetrix gene chip. These deletion mutant expression profiles were compared to that of wild type cells to determine differentially expressed genes regulated by these transcription factors.