Group II intron domain 5 facilitates a trans-splicing reaction.
A self-splicing group II intron of yeast mitochondrial DNA (aI5g) was divided within intron domain 4 to yield two RNAs that trans-spliced in vitro with associated trans-branching of excised intron fragments. Reformation of the domain 4 secondary structure was not necessary for the trans reaction, since domain 4 sequences were shown to be dispensable. Instead, the trans reaction depended on a previously unpredicted interaction between intron domain 5, the most highly conserved region of group II introns, and another region of the RNA. Domain 5 was shown to be essential for cleavage at the 5' splice site. It stimulated that cleavage when supplied as a trans-acting RNA containing only 42 nucleotides of intron sequence. The relevance of our findings to in vivo trans-splicing mechanisms is discussed.
Jarrell
K A
KA
Department of Molecular Genetics, Ohio State University, Columbus 43210-1292.
Dietrich
R C
RC
Perlman
P S
PS
D004591:Electrophoresis, Polyacrylamide Gel; D007438:Introns; D008928:Mitochondria / Q000378:metabolism*; D012326:RNA Splicing; D015003:Yeasts / Q000235:genetics* / Q000648:ultrastructure