Elucidating the role of Zuo1 protein on the translational control of gene expression in Saccharomyces cerevisiae
The ribosome associated complex (RAC) is a ribosome bound protein chaperone complex reported to surveil the translation of proteins with positively charged regions. It has been posited that RAC might be able to directly regulate translation by coupling co-translational folding with the peptide-elongation cycle. To identify the targets of RAC in cells and test the hypothesis that the complex modulates translation, we performed ribosome profiling on wild- type yeast cells and cells lacking a key component of the RAC that binds near the ribosome active site (zuo1?). Ribosome profiling is a sequencing-based technique that allows us to take a nucleotide resolution snapshot of where every ribosome sits on every mRNA in a cell at a given point in time. This powerful approach can provide information about the contributions of individual proteins to the translational landscape of a cell. We identified >300 targets for the RAC, and unexpectedly observed that the ribosome frameshifts on ~10% of these targets in zuo1? cells. The maintenance of ribosome reading frame is essential for cell health because frameshifts can result in the production of non-functional truncated and extended protein products. These studies have the potential to uncover RAC as a critical determinant of translational fidelity in eukaryotic cells. Overall design: mRNA-seq and Ribosome profiling of exponentially growing (OD600 = 0.6) Saccharomyces cerevisiae cells were performed by deep sequencing , in two biological replicates, using Illumina HiSeq-4000 platform.