Structures of RNA complexes with the Escherichia coli RNA pyrophosphohydrolase RppH unveil the basis for specific 5'-end-dependent mRNA decay.

ABSTRACT: 5'-End-dependent RNA degradation impacts virulence, stress responses, and DNA repair in bacteria by controlling the decay of hundreds of mRNAs. The RNA pyrophosphohydrolase RppH, a member of the Nudix hydrolase superfamily, triggers this degradation pathway by removing pyrophosphate from the triphosphorylated RNA 5' terminus. Here, we report the x-ray structures of Escherichia coli RppH (EcRppH) in apo- and RNA-bound forms. These structures show distinct conformations of EcRppH·RNA complexes on the catalytic pathway and suggest a common catalytic mechanism for Nudix hydrolases. EcRppH interacts with RNA by a bipartite mechanism involving specific recognition of the 5'-terminal triphosphate and the second nucleotide, thus enabling discrimination against mononucleotides as substrates. The st

SUBMITTER: Vasilyev N 

PROVIDER: S-EPMC4392254 | biostudies-literature | 2015 Apr

REPOSITORIES: biostudies-literature