FIG. 4.

Transcription of sigB is regulated by SigE and SigH. Primer extension analysis was performed utilizing RNA from wild-type (Rv), sigH mutant (H−), sigE mutant (E−), and sigE/sigH double mutant (EH−) strains of M. tuberculosis. RNA was isolated from each strain in the absence of stress induction (−) and following exposure to 1 mM diamide (+). The intensity of each transcript band, quantified using a PhosphorImager (Molecular Dynamics), is given below the autoradiogram, expressed as relative signal normalized to the intensity of the signal originating from uninduced wild-type RNA.