RNomics in Archaea reveals a further link between splicing of archaeal introns and rRNA processing.
The bulge-helix-bulge (BHB) motif recognised by the archaeal splicing endonuclease is also found in the long processing stems of archaeal rRNA precursors in which it is cleaved to generate pre-16S and pre-23S rRNAs. We show that in two species, Archaeoglobus fulgidus and Sulfolobus solfataricus, representatives from the two major archaeal kingdoms Euryarchaeota and Crenarchaeota, respectively, the pre-rRNA spacers cleaved at the BHB motifs surrounding pre-16S and pre-23S rRNAs subsequently become ligated. In addition, we present evidence that this is accompanied by circularization of ribosomal pre-16S and pre-23S rRNAs in both species. These data reveal a further link between intron splicing and pre-rRNA processing in Archaea, which might reflect a common evolutionary origin of the two processes. One spliced RNA species designated 16S-D RNA, resulting from religation at the BHB motif of 16S pre-rRNA, is a highly abundant and stable RNA which folds into a three-stem structure interrupted by two single-stranded regions as assessed by chemical probing. It spans a region of the pre-rRNA 5' external transcribed spacer exhibiting a highly conserved folding pattern in Archaea. Surprisingly, 16S-D RNA contains structural motifs found in archaeal C/D box small RNAs and binds to the L7Ae protein, a core component of archaeal C/D box RNPs. This supports the notion that it might have an important but still unknown role in pre-rRNA biogenesis or might even target RNA molecules other than rRNA.
Tang
Thean Hock
TH
Institut für Experimentelle Pathologie/Molekulare Neurobiologie (ZMBE), Universität Münster, D-48149 Münster, Germany.
Rozhdestvensky
Timofey S
TS
d'Orval
Béatrice Clouet
BC
Bortolin
Marie-Line
ML
Huber
Harald
H
Charpentier
Bruno
B
Branlant
Christiane
C
Bachellerie
Jean-Pierre
JP
Brosius
Jürgen
J
Hüttenhofer
Alexander
A
D019611:Archaeoglobus fulgidus / Q000235:genetics / Q000378:metabolism; D001483:Base Sequence; D024202:Electrophoretic Mobility Shift Assay; D007438:Introns; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D012322:RNA Precursors / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D012326:RNA Splicing; D019642:RNA, Archaeal / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D012335:RNA, Ribosomal / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D012336:RNA, Ribosomal, 16S / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D012338:RNA, Ribosomal, 23S / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D012269:Ribosomal Proteins / Q000378:metabolism; D012689:Sequence Homology, Nucleic Acid; D016944:Sulfolobus / Q000235:genetics / Q000378:metabolism
D012322:RNA Precursors; D019642:RNA, Archaeal; D012335:RNA, Ribosomal; D012336:RNA, Ribosomal, 16S; D012338:RNA, Ribosomal, 23S; D012269:Ribosomal Proteins