MarR family of transcription factors includes diverse regulators that control expression of genes involved various adaptive molecular mechanisms, including antibiotic and antimicrobial stress resistance, oxidative stress response, heat shock resistance and virulence [21432936, 22022447]. MarR-family regulators exist as dimers and bind palindromic sequences within target promoters, resulting in either transcriptional repression or activation (and sometimes both). In absence of a ligand, MarR-family regulators bind specifically their DNA sites, most often resulting in repression of gene activity.
On binding of the ligand, DNA binding is attenuated, resulting in de-repression of transcription [21432936
]. MarR-family regulators respond to a wide variety of environmental signals, such as peroxide, zinc ions, uric acid, aromatic compounds [20716550
]. MarR-family proteins share a characteristic winged HTH DNA binding domain (PF01047).