Combinatorial Regulation by a Novel Arrangement of FruA and MrpC2 Transcription Factors during Myxococcus xanthus Development

摘要: Myxococcus xanthus is a gram-negative soil bacterium that undergoes multicellular development upon nutrient limitation. Intercellular signals control cell movements and regulate gene expression during the developmental process. C-signal short-range signal essential for aggregation sporulation. C-signaling regulates fmgA by novel mechanism involving cooperative binding of response regulator FruA transcription factor/antitoxin MrpC2. Here, we demonstrate regulation C-signal-dependent fmgBC operon under similar combinatorial MrpC2, but arrangement sites different than in promoter region. MrpC2 was shown to bind crucial cis-regulatory sequence required MrpC and/or associate with region vivo, an fmgB-lacZ fusion abolished fruA mutant. Recombinant regulatory located slightly downstream MrpC2-binding site Full-length FruA, not its C-terminal DNA-binding domain, enhanced formation complexes DNA, when combined This effect nearly DNA fragments having mutation either MrpC2- or FruA-binding site, indicating both proteins important enhancement complex formation. These results are those observed fmgA, where cooperatively upstream promoter, except site. Cooperative appears be conserved allows flexible coordinates multiple signaling pathways.