4oxp

Publication Abstract from PubMed

The endoribonuclease RNase E is a key enzyme in RNA metabolism for many bacterial species. In Escherichia coli, RNase E contributes to the majority of RNA turnover and processing events, and the enzyme has been extensively characterized as the central component of the RNA degradosome assembly. A similar RNA degradosome assembly has been described in the alpha-proteobacterium Caulobacter crescentus, with the interacting partners of RNase E identified as the Kreb's cycle enzyme aconitase, a DEAD-box RNA helicase RhlB and the exoribonuclease polynucleotide phosphorylase. Here we report that an additional degradosome component is the essential exoribonuclease RNase D, and its recognition site within RNase E is identified. We show that, unlike its E. coli counterpart, C. crescentus RhlB interacts directly with a segment of the N-terminal catalytic domain of RNase E. The crystal structure of a portion of C. crescentus RNase E encompassing the helicase-binding region is reported. This structure reveals that an inserted segment in the S1 domain adopts an alpha-helical conformation, despite being predicted to be natively unstructured. We discuss the implications of these findings for the organization and mechanisms of the RNA degradosome.

Molecular recognition of RhlB and RNase D in the Caulobacter crescentus RNA degradosome.,Voss JE, Luisi BF, Hardwick SW Nucleic Acids Res. 2014 Dec 1;42(21):13294-305. doi: 10.1093/nar/gku1134. Epub, 2014 Nov 11. PMID:25389270^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.