title: 5'-to-3' exoribonuclease activity in bacteria: role of RNase J1 in rRNA maturation and 5' stability of mRNA.
abstract: Although the primary mechanism of eukaryotic messenger RNA decay is exoribonucleolytic degradation in the 5'-to-3' orientation, it has been widely accepted that Bacteria can only degrade RNAs with the opposite polarity, i.e. 3' to 5'. Here we show that maturation of the 5' side of Bacillus subtilis 16S ribosomal RNA occurs via a 5'-to-3' exonucleolytic pathway, catalyzed by the widely distributed essential ribonuclease RNase J1. The presence of a 5'-to-3' exoribonuclease activity in B. subtilis suggested an explanation for the phenomenon whereby mRNAs in this organism are stabilized for great distances downstream of "roadblocks" such as stalled ribosomes or stable secondary structures, whereas upstream sequences are never detected. We show that a 30S ribosomal subunit bound to a Shine Dalgarno-like element (Stab-SD) in the cryIIIA mRNA blocks exonucleolytic progression of RNase J1, accounting for the stabilizing effect of this element in vivo.
authors.affiliation: CNRS UPR 9073 (affiliated with Université de Paris 7 - Denis Diderot), Institut de Biologie Physico-Chimique, 13 rue Pierre et Marie Curie, 75005 Paris.
authors.forename: Nathalie
authors.initials: N
authors.lastname: Mathy
authors.forename: Lionel
authors.initials: L
authors.lastname: Bénard
authors.forename: Olivier
authors.initials: O
authors.lastname: Pellegrini
authors.forename: Roula
authors.initials: R
authors.lastname: Daou
authors.forename: Tingyi
authors.initials: T
authors.lastname: Wen
authors.forename: Ciarán
authors.initials: C
authors.lastname: Condon
mesh_terms: D001412:Bacillus subtilis / Q000201:enzymology* / Q000235:genetics; D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D001427:Bacterial Toxins / Q000235:genetics / Q000378:metabolism; D004731:Endotoxins / Q000235:genetics / Q000378:metabolism; D005095:Exoribonucleases / Q000235:genetics / Q000378:metabolism*; D015964:Gene Expression Regulation, Bacterial / Q000235:genetics; D006460:Hemolysin Proteins / Q000235:genetics / Q000378:metabolism; D021122:Protein Subunits / Q000235:genetics / Q000378:metabolism; D020871:RNA Stability / Q000235:genetics*; D012333:RNA, Messenger / Q000096:biosynthesis* / Q000235:genetics; D012335:RNA, Ribosomal / Q000096:biosynthesis* / Q000235:genetics
chemical_list: D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins; D001427:Bacterial Toxins; D004731:Endotoxins; D006460:Hemolysin Proteins; D021122:Protein Subunits; D012333:RNA, Messenger; D012335:RNA, Ribosomal; C030956:insecticidal crystal protein, Bacillus Thuringiensis; D005095:Exoribonucleases