The role of small nuclear RNAs in RNA splicing.

Recent genetic and biochemical experiments have revealed an intimate and dynamic role for small nuclear RNAs (snRNAs) in multiple steps of RNA-splicing reactions. Both snRNA-substrate and snRNA-snRNA interactions are involved. These interactions concern not only splice site and branch point definition, but also the catalytic reactions of the first and second steps of splicing. Studies reveal a striking conservation between snRNA interactions and interactions found in RNAs encoded by genes with group II self-splicing introns.