THIOPHOSPHATE INTERFERENCE EXPERIMENTS LOCATE PHOSPHATES IMPORTANT FOR THE HAMMERHEAD RNA SELF-CLEAVAGE REACTION

A hammerhead domain of less than 50 nucleotides is responsible for a self-cleavage reaction in the replication of plant RNA pathogens. The hammerhead is composed of three helices joining at a central conserved core of 11 single stranded nucleotides. The core is believed to fold into a tertiary structure that provides functional groups for catalysis and to coordinate one or more divalent metal ions. In this study we use a phosphorothioate substitution interference assay to identify four phosphates in the conserved core which also play a role in the self-cleavage reaction. © 1990 Oxford University Press.