Comparison of the transcription profile of B. subtilis clpX strain with B. subtilis clpX spx strain, reporting on Spx activity. Bacillus subtilis

In B. subtilis the unusual transcription factor Spx controls the thiol stress response regulon (Nakano et al 2003 PNAS 100:13603; Rochat et a. 2012 NAR 40:9751). Under normal growth conditions Spx is constantly degraded by the AAA+ protease complex ClpXP (Nakano et al 2001 MolMi 42:383). Comparing a B. subtilis clpX strain, where Spx levels are high, with a B. subtilis clpX spx double mutant strain which lacks Spx, will report on Spx dependent transcriptional control. We prepared total RNA of exponentially grown B. subtilis clpX and of B. subtilis clpX spx cells. Overall design: Using a merged dye swap experiments of red or green labelled cDNA of the above described RNA preparations-