The mechanism of group I self-splicing: an internal guide sequence can be provided in trans.
We have reconstituted a group I self-splicing reaction between two RNA molecules with different functional RNA parts: a substrate molecule containing the 5' splice site and a functional internal guide sequence (IGS), and a ribozyme molecule with core structure elements and splice sites but a mutated IGS. The 5' exon of the substrate molecule is ligated in trans to the 3' exon of the ribozyme molecule, suggesting that the deficient IGS in the ribozyme can be replaced by an externally added IGS present on the substrate molecule. This result is different from catalysis mediated by proteins where it is not possible to dissect the specificity of an enzyme from its catalytic activity.
Winter
A J
AJ
E.C. Slater Institute for Biochemical Research, University of Amsterdam, The Netherlands.
Groot Koerkamp
M J
MJ
Tabak
H F
HF
D000818:Animals; D001483:Base Sequence; D002384:Catalysis; D005091:Exons; D007438:Introns; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009154:Mutation; D012322:RNA Precursors / Q000378:metabolism*; D012326:RNA Splicing; D016337:RNA, Catalytic; D012335:RNA, Ribosomal / Q000378:metabolism*; D013768:Tetrahymena / Q000235:genetics*
D012322:RNA Precursors; D016337:RNA, Catalytic; D012335:RNA, Ribosomal