Selective mRNA degradation by polynucleotide phosphorylase in cold shock adaptation in Escherichia coli.
Upon cold shock, Escherichia coli cell growth transiently stops. During this acclimation phase, specific cold shock proteins (CSPs) are highly induced. At the end of the acclimation phase, their synthesis is reduced to new basal levels, while the non-cold shock protein synthesis is resumed, resulting in cell growth reinitiation. Here, we report that polynucleotide phosphorylase (PNPase) is required to repress CSP production at the end of the acclimation phase. A pnp mutant, upon cold shock, maintained a high level of CSPs even after 24 h. PNPase was found to be essential for selective degradation of CSP mRNAs at 15 degrees C. In a poly(A) polymerase mutant and a CsdA RNA helicase mutant, CSP expression upon cold shock was significantly prolonged, indicating that PNPase in concert with poly(A) polymerase and CsdA RNA helicase plays a critical role in cold shock adaptation.
Yamanaka
K
K
Department of Biochemistry, Robert Wood Johnson Medical School, Piscataway, New Jersey 08854, USA.
Inouye
M
M
D000220:Adaptation, Biological; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D003080:Cold Temperature; D053487:DEAD-box RNA Helicases; D015536:Down-Regulation; D004926:Escherichia coli / Q000378:metabolism / Q000502:physiology*; D029968:Escherichia coli Proteins; D009154:Mutation; D011117:Polyribonucleotide Nucleotidyltransferase / Q000235:genetics / Q000502:physiology*; D020365:RNA Helicases / Q000235:genetics / Q000502:physiology; D012333:RNA, Messenger / Q000378:metabolism; D013997:Time Factors; D014157:Transcription Factors
D001426:Bacterial Proteins; D029968:Escherichia coli Proteins; D012333:RNA, Messenger; D014157:Transcription Factors; C062260:cold shock protein CS7.4, Bacteria; D011117:Polyribonucleotide Nucleotidyltransferase; C088840:deaD protein, E coli; D053487:DEAD-box RNA Helicases; D020365:RNA Helicases