Escherichia coli RNase R has dual activities, helicase and RNase.

ABSTRACT: In Escherichia coli, the cold shock response occurs when there is a temperature downshift from 37 degrees C to 15 degrees C, and this response is characterized by induction of several cold shock proteins, including the DEAD-box helicase CsdA, during the acclimation phase. CsdA is involved in a variety of cellular processes. Our previous studies showed that the helicase activity of CsdA is critical for its function in cold shock acclimation of cells and that the only proteins that were able to complement its function were another helicase, RhlE, an RNA chaperone, CspA, and a cold-inducible exoribonuclease, RNase R. Interestingly, other major 3'-to-5' processing exoribonucleases of E. coli, such as polynucleotide phosphorylase and RNase II, cannot complement the cold shock function of CsdA.

SUBMITTER: Awano N 

PROVIDER: S-EPMC2820863 | biostudies-literature | 2010 Mar

REPOSITORIES: biostudies-literature