Paper Chase is a research database designed to offer abstracts of research articles published in journals that have a highly rated impact factor as determined by ISI Impact Factor and PageRank. Abstracts are organized by date, with the most recently published papers listed first. 

Paper Chase

RNA structure, not sequence, determines the 5' splice-site specificity of a group I intron.

Proc. Natl. Acad. Sci. U.S.A.. 10 1, 1989;86(19):7402-6.
Doudna JA, Cormack BP, Szostak JW.

Department of Molecular Biology, Massachusetts General Hospital, Boston 02114.

Abstract:

The group I self-splicing introns act at exon-intron junctions without recognizing a particular sequence. In order to understand splice-site selection, we have developed an assay system based on the Tetrahymena ribozyme to allow the study of numerous 5'-splice-site variants. Cleavage at the correct site requires formation of the correct secondary structure and occurs most efficiently within a 3-base-pair window centered on base pair 5 from the bottom of the P1 stem. Within this window the ribozyme recognizes and cleaves at a "wobble" base pair; the base pair above the cleavage site also influences splicing efficiency. The recognition of RNA structure rather than sequence explains the ability of these transposable introns to splice out of a variety of sequence contexts.