Distinguishing features of guide and substrate RNA recognition by H/ACA snoRNPs

H/ACA small nucleolar ribonucleoproteins (snoRNPs) pseudouridylate RNA in eukaryotes and archaea. They consist of four proteins and a guide RNA. It is unclear which element of the guide RNA the H/ACA proteins recognize. By designing guide RNA variants with altered structural features, I determined that H/ACA proteins bind guide RNA extremely tightly, but non-specifically in vitro. Additionally, the base-pairing between guide and substrate RNA varies widely in nature. To elucidate substrate selection rules, I systematically altered the sequence of a substrate RNA and tested for snoRNP binding and activity. All substrate RNA variants tested are bound by the H/ACA snoRNP, but not all are effectively modified. Minimal continuous base pairing is required to position the target uridine in the active site for modification, and H/ACA snoRNPs can target structured RNAs. This information will improve the prediction of novel target sites of H/ACA snoRNPs, e.g. in messenger RNAs.

Authors

• Kelly, Erin Katelyn
• University of Lethbridge. Faculty of Arts and Science

• RNA modification
• H/ACA snoRNP
• Saccharomyces cerevisiae
• guide RNA
• substrate RNA
• Pseudouridine
• Nucleoproteins
• Non-coding RNA
• Molecular biology
• Dissertations, Academic

Identifier

hdl:10133/5247

OAI identifier oai:identifier

oai:opus.uleth.ca:10133/5247