Regulation of two-component regulatory system genes by active protein degradation of transcription factor

2014 Fiscal Year Final Research Report

• Project/Area Number: 24580123
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Applied microbiology
• Research Institution: Tokai University
• Principal Investigator: OGURA Mitsuo 東海大学, 海洋研究所, 教授 (80204163)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: タンパク質分解 / ATP依存性プロテアーゼ / 遺伝子発現 / DNA結合 / グルコース誘導

Outline of Final Research Achievements

The DegS-DegU two-component regulatory system regulates many cellular events in Bacillus subtilis. Genes for DegSU are composed of an operon directed by the P1 promoter.
Spx regulates diamide-stress regulon in addition to many unknown genes and is a substrate of the ATP-dependent ClpXP protease. We have found that null mutations for clpX and clpP, which encode subunits for ClpXP, enhanced the DegU amount through activation of the P1 promoter. We isolated four suppressors for the clpP-enhancing effect. Whole-genome sequencing of the suppressors revealed that the strains have a point mutation or deletion in spx. The clpP-enhancing effect on degS-lacZ expression was abolished in the spx disruptant. These results showed that the degSU operon is a new target of positive regulation by Spx. Furthermore, we found that the P1 promoter was induced by glucose and that this induction was greatly reduced in the spx mutant. These results suggested that Spx is involved in glucose induction.

Free Research Field

細菌分子生物学