title: Heat shock transcription factor δ³² is targeted for degradation via an ubiquitin-like protein ThiS in Escherichia coli.
abstract: The posttranslational modification of proteins with ubiquitin and ubiquitin-like proteins (UBLs) plays an important role in eukaryote biology, through which substrate proteins are targeted for degradation by the proteasome. Prokaryotes have been thought to degrade proteins by an ubiquitin independent pathway. Here, we show that ThiS, an ubiquitin-like protein, is covalently attached to δ(32) and at least 27 other proteins, leading to their subsequent degradation by proteases, in a similar manner to the ubiquitin-proteasome system (UPS) in eukaryotes. Molecular biology and biochemical studies confirm that specific lysine sites in δ(32) can be modified by ThiS. The results presented here establish a new model for δ(32) degradation and show that Escherichia coli uses a small-protein modifier to control protein stability.
authors.affiliation: Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu 610064, China.
authors.forename: Xibing
authors.initials: X
authors.lastname: Xu
authors.affiliation: Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu 610064, China.
authors.forename: Yulong
authors.initials: Y
authors.lastname: Niu
authors.affiliation: Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu 610064, China.
authors.forename: Ke
authors.initials: K
authors.lastname: Liang
authors.affiliation: Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu 610064, China.
authors.forename: Jianmei
authors.initials: J
authors.lastname: Wang
authors.affiliation: Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu 610064, China.
authors.forename: Xufeng
authors.initials: X
authors.lastname: Li
authors.affiliation: Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu 610064, China. Electronic address: yangyi528@scu.edu.cn.
authors.forename: Yi
authors.initials: Y
authors.lastname: Yang
mesh_terms: D000595:Amino Acid Sequence; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism*; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000235:genetics / Q000378:metabolism*; D006360:Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism*; D018869:Heat-Shock Response; D008954:Models, Biological; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000235:genetics / Q000378:metabolism; D046988:Proteasome Endopeptidase Complex / Q000378:metabolism; D059748:Proteolysis; D012808:Sigma Factor / Q000235:genetics / Q000378:metabolism*; D014452:Ubiquitins / Q000378:metabolism
chemical_list: D002352:Carrier Proteins; D029968:Escherichia coli Proteins; D006360:Heat-Shock Proteins; D010446:Peptide Fragments; D012808:Sigma Factor; D014452:Ubiquitins; C069774:heat-shock sigma factor 32; C411655:thiS protein, E coli; D046988:Proteasome Endopeptidase Complex
keywords: Escherichia coli; ThiS; Ubiquitin-like protein; δ(32)