Impact of mIHF on gene expression

mIHF is a possible nucleoid associated protein. Its effect on gene regulation remains unknown. We performed an RNA-seq analysis of the mihF conditional knock-down mutant in Mycobacterium tuberculosis. We show that mihF is essential for in vitro growth and that depeltion of mIHF results in deregulation of a large number of genes. Notably, the most downregulated gene was the espACD operon, which is necessary for secretion of M. tuberculosis main virulence factor EsxA. Overall design: The mihF conditional knock-down (mihF-cKD) has an anhydrotetracycline (ATc)-inducible promoter. The comparison was done between the presence and the absence of ATc in the growing medium of mihF-cKD, i.e. exprssed vs. non-expressed mihF. To check for the possible influence of ATc alone on gene expression, presence and absence of ATc in the growing medium was compared in a wild-type strain. All conditions were repeated twice.