title: Processing of Bacillus subtilis small cytoplasmic RNA: evidence for an additional endonuclease cleavage site.
abstract: Small cytoplasmic RNA (scRNA) of Bacillus subtilis is the RNA component of the signal recognition particle. scRNA is transcribed as a 354-nt precursor, which is processed to the mature 271-nt scRNA. Previous work demonstrated the involvement of the RNase III-like endoribonuclease, Bs-RNase III, in scRNA processing. Bs-RNase III was found to cleave precursor scRNA at two sites (the 5' and 3' cleavage sites) located on opposite sides of the stem of a large stem-loop structure, yielding a 275-nt RNA, which was then trimmed by a 3' exoribonuclease to the mature scRNA. Here we show that Bs-RNase III cleaves primarily at the 5' cleavage site and inefficiently at the 3' site. RNase J1 is responsible for much of the cleavage that releases scRNA from downstream sequences. The subsequent exonucleolytic processing is carried out largely by RNase PH.
authors.affiliation: Mount Sinai School of Medicine of New York University, New York, NY 10029, USA.
authors.forename: Shiyi
authors.initials: S
authors.lastname: Yao
authors.forename: Joshua B
authors.initials: JB
authors.lastname: Blaustein
authors.forename: David H
authors.initials: DH
authors.lastname: Bechhofer
mesh_terms: D001412:Bacillus subtilis / Q000201:enzymology* / Q000235:genetics; D001483:Base Sequence; D004722:Endoribonucleases / Q000378:metabolism*; D005095:Exoribonucleases / Q000235:genetics / Q000378:metabolism; D008969:Molecular Sequence Data; D009154:Mutation; D012322:RNA Precursors / Q000737:chemistry / Q000378:metabolism; D012323:RNA Processing, Post-Transcriptional; D020733:RNA, Small Cytoplasmic / Q000737:chemistry / Q000378:metabolism*; D043244:Ribonuclease III / Q000378:metabolism; D013728:Terminator Regions, Genetic
chemical_list: D012322:RNA Precursors; D020733:RNA, Small Cytoplasmic; D004722:Endoribonucleases; D005095:Exoribonucleases; D043244:Ribonuclease III