Functional and structural impact of target uridine substitutions on the H/ACA ribonucleoprotein particle pseudouridine synthase.

ABSTRACT: Box H/ACA ribonucleoprotein protein particles catalyze the majority of pseudouridylation in functional RNA. Different from stand alone pseudouridine synthases, the RNP pseudouridine synthase comprises multiple protein subunits and an RNA subunit. Previous studies showed that each subunit, regardless its location, is sensitive to the step of subunit placement at the catalytic center and potentially to the reaction status of the substrate. Here we describe the impact of chemical substitutions of target uridine on enzyme activity and structure. We found that 3-methyluridine in place of uridine inhibited its isomerization while 2'-deoxyuridine or 4-thiouridine did not. Significantly, crystal structures of an archaeal box H/ACA RNP bound with the nonreactive and the two postreactive substrate a

SUBMITTER: Zhou J 

PROVIDER: S-EPMC2928259 | biostudies-literature | 2010 Jul

REPOSITORIES: biostudies-literature