Deletion of nonconserved helices near the 3' end of the rRNA intron of Tetrahymena thermophila alters self-splicing but not core catalytic activity.
Barfod ET, Cech TR. Deletion of nonconserved helices near the 3' end of the rRNA intron of Tetrahymena thermophila alters self-splicing but not core catalytic activity. Genes Dev. 1988 Jun; 2(6):652-63.