GENETIC AND BIOCHEMICAL ANALYSES OF YEAST RNASE MRP

RNase MRP cleaves the yeast pre-rRNA at a site in internal transcribed spacer 1 (ITS 1) and this cleavage can be reproduced in vitro by the highly purified enzyme. Two protein components (Pop Ip and Pop2p) have been identified which are common to yeast RNase MRP and RNase P. More over, purified RNase P can also cleave the pre-rRNA substrate in vitro , underlining the similarities between these particles. Genetic eviden ce suggests that RNase MRP functionally interacts with the snoRNPs whi ch are required for other pre-rRNA processing reactions.