InterPro domain: IPR039420

This family contains proteins that have a signal transduction response regulator receiver domain at the N terminus and a OmpR/PhoB-type DNA-binding domain at the C terminus. Homologues are predominantly from bacteria, but also eukaryotes and archaea. Members of the family are frequently part of a two-component regulatory system, including:

• Transcriptional regulatory protein WalR, a member of the two-component regulatory system with WalK involved in the regulation of the ftsAZ operon and others [ 1 ]
• Heme response regulator HssR, a member of the two-component regulatory system with HssS involved in intracellular heme homeostasis and tempering of staphylococcal virulence.
• Response regulator protein GraR, a member of the two-component regulatory system with GraS involved in resistance against cationic antimicrobial peptides [ 2 ]
• Response regulator MprA, a member of the two-component regulatory system with MprB which contributes to maintaining a persistent infection in the host [ 3 ]
• Response regulator ArlR, a member of the two-component regulatory system with ArlS involved in the regulation of adhesion, autolysis, multidrug resistance and virulence [ 4 ]
• Response regulator SaeR, a member of the two-component regulatory system with SaeS involved in the regulation of staphylococcal virulence factors [ 5 ]

1. The essential two-component regulatory system encoded by yycF and yycG modulates expression of the ftsAZ operon in Bacillus subtilis. Microbiology (Reading, Engl.) 146 ( Pt 7), 1573-83
2. Interaction of the GraRS two-component system with the VraFG ABC transporter to support vancomycin-intermediate resistance in Staphylococcus aureus. Antimicrob. Agents Chemother. 51, 2679-89
3. Functional analysis of the Mycobacterium tuberculosis MprAB two-component signal transduction system. Infect. Immun. 71, 6962-70
4. A new two-component regulatory system involved in adhesion, autolysis, and extracellular proteolytic activity of Staphylococcus aureus. J. Bacteriol. 182, 3955-64
5. Molecular architecture of the regulatory Locus sae of Staphylococcus aureus and its impact on expression of virulence factors. J. Bacteriol. 185, 6278-86