Transcriptional analysis of RelE family toxin overexpression in Mycobacterium tuberculosis

To understand the mechanism of action of the RelE family of toxins on metabolism of Mycobacterium tuberculosis. To this effect, toxin expression was induced under control of a tetracycline regulatable promoter and transcriptional profiles compared during overexpression of the three RelE toxin family members. Profiles were also compared to previously published profiles of drugs of known mechanism of action against this organism. For the design, RNA isolated from cells where toxin expression was induced with anhydrotetracycline was converted to Cy5-labeled cDNA whereas RNA derived from cells in which toxin expression was not induced (treated with ethanol solvent only) was converted to Cy3-labeled cDNA. Time points were taken for each overexpression condition. Treatments were performed indepedently a minimum of two times to give independent biological replicates.