title: Cold shock induces a major ribosomal-associated protein that unwinds double-stranded RNA in Escherichia coli.
abstract: A 70-kDa protein was specifically induced in Escherichia coli when the culture temperature was shifted from 37 to 15 degrees C. The protein was identified to be the product of the deaD gene (reassigned csdA) encoding a DEAD-box protein. Furthermore, after the shift from 37 to 15 degrees C, CsdA was exclusively localized in the ribosomal fraction and became a major ribosomal-associated protein in cells grown at 15 degrees C. The csdA deletion significantly impaired cell growth and the synthesis of a number of proteins, specifically the derepression of heat-shock proteins, at low temperature. Purified CsdA was found to unwind double-stranded RNA in the absence of ATP. Therefore, the requirement for CsdA in derepression of heat-shock protein synthesis is a cold shock-induced function possibly mediated by destabilization of secondary structures previously identified in the rpoH mRNA.
authors.affiliation: Department of Biochemistry, University of Medicine and Dentistry of New Jersey, Robert Wood Johnson Medical School, Piscataway 08854, USA.
authors.forename: P G
authors.initials: PG
authors.lastname: Jones
authors.forename: M
authors.initials: M
authors.lastname: Mitta
authors.forename: Y
authors.initials: Y
authors.lastname: Kim
authors.forename: W
authors.initials: W
authors.lastname: Jiang
authors.forename: M
authors.initials: M
authors.lastname: Inouye
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry / Q000378:metabolism*; D018834:Chaperonin 60 / Q000235:genetics; D003080:Cold Temperature; D053487:DEAD-box RNA Helicases; D015180:Electrophoresis, Gel, Two-Dimensional; D004926:Escherichia coli; D029968:Escherichia coli Proteins; D015964:Gene Expression Regulation, Bacterial; D018840:HSP70 Heat-Shock Proteins / Q000235:genetics; D008969:Molecular Sequence Data; D016254:Mutagenesis, Insertional; D009690:Nucleic Acid Conformation; D020365:RNA Helicases; D012329:RNA, Bacterial / Q000737:chemistry*; D012330:RNA, Double-Stranded / Q000737:chemistry*; D016601:RNA-Binding Proteins / Q000737:chemistry / Q000378:metabolism*; D012270:Ribosomes / Q000737:chemistry
chemical_list: D001426:Bacterial Proteins; D018834:Chaperonin 60; D029968:Escherichia coli Proteins; D018840:HSP70 Heat-Shock Proteins; D012329:RNA, Bacterial; D012330:RNA, Double-Stranded; D016601:RNA-Binding Proteins; C088840:deaD protein, E coli; C063842:dnaK protein, E coli; D053487:DEAD-box RNA Helicases; D020365:RNA Helicases