Structure-function analysis from the outside in: long-range tertiary contacts in RNA exhibit distinct catalytic roles.

ABSTRACT: The conserved catalytic core of the Tetrahymena group I ribozyme is encircled by peripheral elements. We have conducted a detailed structure-function study of the five long-range tertiary contacts that fasten these distal elements together. Mutational ablation of each of the tertiary contacts destabilizes the folded ribozyme, indicating a role of the peripheral elements in overall stability. Once folded, three of the five tertiary contact mutants exhibit defects in overall catalysis that range from 20- to 100-fold. These and the subsequent results indicate that the structural ring of peripheral elements does not act as a unitary element; rather, individual connections have distinct roles as further revealed by kinetic and thermodynamic dissection of the individual reaction steps. Ablation

SUBMITTER: Benz-Moy TL 

PROVIDER: S-EPMC3186870 | biostudies-literature | 2011 Oct

REPOSITORIES: biostudies-literature