Project description:Ribosome profiling (Ribo-Seq) and RNA-Seq analysis of Saccharomyces cerevisiae with and without 10 minute glucose starvation to determine effects on translation.
Project description: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 (zuo1Δ). 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 zuo1Δ 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.
Project description:CHX is an inhibitor of translation elongation often used in ribosome profiling experiments. There is evidence that CHX treatment of cells may cause artefacts in the distribution of ribosomes on mRNAs. We investigate this possibility in S. pombe by performing ribosome profiling in the presence and absence of this drug.
Project description:The development of the ribosome profiling (ribo-seq) technique has enabled the measurement of translation at a genome-wide level. There are several variants of the ribosome profiling technique that use different translation inhibitors. The regular ribo-seq utilizes Cycloheximide (CHX), a translation elongation inhibitor to freeze all translating ribosomes. In contrast to CHX, the translation inhibitor lactimidomycin (LTM) and harringtonine (Harr) have a much stronger effect on initiating ribosomes. The use of these inhibitors allows for the global mapping of translating initiating sites (TISs) when they are coupled with ribosome profiling (TI-seq). We have developed a computational tool to detect and/or quantitatively compare translation initiation from TI-seq data, and predict novel ORFs from regular CHX-based ribo-seq data. Two replicates of CHX-based ribo-seq experiments and one Harr based ribo-seq were performed in HEK293 cells for confirming the ORFs predicted using public available data.
Project description:Ribosome profiling with translation inhibitors reveals pervasive translation in murine ES cells. Ribosome profiling or stranded RNAseq (ribominus) with murine embryonic stem cells treated with either DMD-pateamineA, Puromycin, Harringtonine or vehicle (no drug control). Two replicates per condition.
