Physical Sciences and Mathematics Commons^™

Investigating The Mechanisms Of A Novel Ribosomal Rna Degradation System, Daniel Fowler

Honors Theses

Nonfunctional ribosomal RNA decay (NRD) is a novel quality control system that eliminates defective ribosomal RNAs (rRNAs) from yeast cells. Plasmid-encoded rRNAs containing single nucleotide substitutions in the peptidyl transferase center of 25S rRNA or the decoding center of 18S rRNA are co-expressed with endogenous rRNAs in Saccharomyces cerevisiae. Quantitative northern blots reveal the steady-state levels of the resulting nonfunctional rRNAs are markedly decreased compared to wild-type rRNAs . Furthermore, the decreased expression is not the result ofdefects in rRNA transcription or processing, but instead is due to decreased stability ofthe mature, nonfunctional rRNAs. Mutations in other functionally important rRNA …