The tyrosine kinase McsB is a regulated adaptor protein for ClpCP.
Cells of the soil bacterium Bacillus subtilis have to adapt to fast environmental changes in their natural habitat. Here, we characterized a novel system in which cells respond to heat shock by regulatory proteolysis of a transcriptional repressor CtsR. In B. subtilis, CtsR controls the synthesis of itself, the tyrosine kinase McsB, its activator McsA and the Hsp100/Clp proteins ClpC, ClpE and their cognate peptidase ClpP. The AAA+ protein family members ClpC and ClpE can form an ATP-dependent protease complex with ClpP and are part of the B. subtilis protein quality control system. The regulatory response is mediated by a proteolytic switch, which is formed by these proteins under heat-shock conditions, where the tyrosine kinase McsB acts as a regulated adaptor protein, which in its phosphorylated form activates the Hsp100/Clp protein ClpC and targets the repressor CtsR for degradation by the general protease ClpCP.
Kirstein
Janine
J
Institut für Biologie, Mikrobiologie, FB Biologie, Chemie, Pharmazie, Freie Universität Berlin, Berlin, Germany.
Dougan
David A
DA
Gerth
Ulf
U
Hecker
Michael
M
Turgay
Kürşad
K
D001412:Bacillus subtilis / Q000201:enzymology* / Q000502:physiology; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D017931:DNA Primers; D015971:Gene Expression Regulation, Enzymologic; D006360:Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism*; D018869:Heat-Shock Response / Q000502:physiology*; D016297:Mutagenesis, Site-Directed; D010766:Phosphorylation; D011494:Protein Kinases / Q000378:metabolism*; D012097:Repressor Proteins / Q000378:metabolism*
D001426:Bacterial Proteins; C087481:ClpC protein, Bacteria; C118338:CtsR protein, bacteria; D017931:DNA Primers; D006360:Heat-Shock Proteins; D012097:Repressor Proteins; D011494:Protein Kinases; C423322:McsB protein, Bacillus subtilis