The Department of Biochemistry's weekly BCH 252 seminar series is presented this week by

Michael Lawson, Assistant Professor of Biochemistry, UCLA

Seminar Title: "Defining the Pathways of Eukaryotic Translational Quality Control"

Abstract: It was unclear how eukaryotic translation termination, which liberates newly synthesized polypeptides from the ribosome, is fast yet also specific for stop codons. We used an in vitro-reconstituted yeast translation system and single-molecule assays to directly observe the molecular choreography that underlies translation termination. We found that the highly conserved eukaryotic release factors bind rapidly to ribosomes and elicit termination via a multistep process that is similar to the selection of proper tRNAs in translation elongation. We further discovered that diverse effectors inhibit translation termination to promote stop codon read through, suggesting a new route to treat the 11% of heritable human diseases caused by premature stop codons. In the future, these technologies will be applied to understanding the molecular mechanisms used by ribosomes and decay factors to evaluate stop codons in Nonsense-Mediated Decay.

Seminar Host: Dr. Seán O'Leary; sean.oleary@ucr.edu