The researchers found that deletion of the yeast gene ISY1 reduces the efficiency of the first step of the splicing reaction and decreases 3'-splice site accuracy. Dr. Villa and Guthrie believe that Isy1p interacts with the ATPase Prp16p to regulate spliceosomal conformation, and thereby the fidelity of pre-mRNA splicing.
Dr. Guthrie explains that "15 years ago we hypothesized that the ATPase Prp16 acted as a proofreading clock to limit errors in splicing; the isolation of a Prp16 antagonist (Isy1) provides critical validation for this model and identifies an unexpected fidelity factor."
Genes & Development