Regulation of gene transcription is the initial step in the complex process that controls gene expression within bacteria. Transcriptional control involves the joint effort of RNA polymerases and numerous other regulatory factors. Whether global or local, positive or negative, regulators play an essential role in the bacterial cell. For instance, some regulators specifically modify the transcription of virulence genes, thereby being indispensable to pathogenic bacteria. Here, we provide a comprehensive overview of important transcription factors and DNA-binding proteins described for the virulent bacterium Francisella tularensis, the causative agent of tularemia. This is an unexplored research area, and the poorly described networks of transcription factors merit additional experimental studies to help elucidate the molecular mechanisms of pathogenesis in this bacterium, and how they contribute to disease.

Department of Clinical Microbiology Umeå University SE 901 85 Umeå Sweden

Department of Molecular Pathology and Biology Faculty of Military Health Sciences University of Defence Trebesska 1575 50001 Hradec Kralove Czech Republic

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Breaking the cellular defense: the role of autophagy evasion in Francisella virulence

Bacteriophage SPO1 protein Gp46 suppresses functions of HU protein in Francisella tularensis

Arginine 58 is indispensable for proper function of the Francisella tularensis subsp. holarctica FSC200 HU protein, and its substitution alters virulence and mediates immunity against wild-type strain

Early infection-induced natural antibody response