title: An RNA pyrophosphohydrolase triggers 5'-exonucleolytic degradation of mRNA in Bacillus subtilis.
abstract: In Escherichia coli, RNA degradation often begins with conversion of the 5'-terminal triphosphate to a monophosphate, creating a better substrate for internal cleavage by RNase E. Remarkably, no homolog of this key endonuclease is present in many bacterial species, such as Bacillus subtilis and various pathogens. Here, we report that the degradation of primary transcripts in B. subtilis can nevertheless be triggered by an analogous process to generate a short-lived, monophosphorylated intermediate. Like its E. coli counterpart, the B. subtilis RNA pyrophosphohydrolase that catalyzes this event is a Nudix protein that prefers unpaired 5' ends. However, in B. subtilis, this modification exposes transcripts to rapid 5' exonucleolytic degradation by RNase J, which is absent in E. coli but present in most bacteria lacking RNase E. This pathway, which closely resembles the mechanism by which deadenylated mRNA is degraded in eukaryotic cells, explains the stabilizing influence of 5'-terminal stem-loops in such bacteria.
authors.affiliation: Kimmel Center for Biology and Medicine at the Skirball Institute and Department of Microbiology, New York University School of Medicine, 540 First Avenue, New York, NY 10016, USA.
authors.forename: Jamie
authors.initials: J
authors.lastname: Richards
authors.forename: Quansheng
authors.initials: Q
authors.lastname: Liu
authors.forename: Olivier
authors.initials: O
authors.lastname: Pellegrini
authors.forename: Helena
authors.initials: H
authors.lastname: Celesnik
authors.forename: Shiyi
authors.initials: S
authors.lastname: Yao
authors.forename: David H
authors.initials: DH
authors.lastname: Bechhofer
authors.forename: Ciarán
authors.initials: C
authors.lastname: Condon
authors.forename: Joel G
authors.initials: JG
authors.lastname: Belasco
mesh_terms: D001412:Bacillus subtilis / Q000235:genetics*; D001426:Bacterial Proteins / Q000235:genetics / Q000502:physiology; D010766:Phosphorylation; D011755:Pyrophosphatases / Q000235:genetics / Q000502:physiology; D020871:RNA Stability; D012329:RNA, Bacterial / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism*; D012260:Ribonucleases / Q000378:metabolism / Q000502:physiology; D000096964:Nudix Hydrolases
chemical_list: D001426:Bacterial Proteins; D011755:Pyrophosphatases; D012329:RNA, Bacterial; D012333:RNA, Messenger; D012260:Ribonucleases; D000096964:Nudix Hydrolases