Project description:The ribosome has considerably increased in size during metazoan evolution in the form of an RNA shell that could serve as a platform for yet unknown protein interactions. Here, we have comprehensively identified the mammalian ‘ribo-interactome’ by establishing a ribosome affinity purification method. Our findings reveal a multitude of novel ribosome interacting factors, encompassing unanticipated functional categories including energy metabolism, cell redox homeostasis, as well as key protein and RNA modifying enzymes. These findings led us to characterize ufmylation, a novel posttranslational modification on ribosomes, and define its substrates. We further show that pyruvate kinase, a key enzyme for stem cell and cancer metabolism, is an RNA binding protein that unexpectedly interacts with specialized sub-pools of ribosomes at the endoplasmic reticulum (ER) and coordinates the localization and translation of ER destined mRNAs. Collectively, these studies uncover that the ribo-interactome imbues a new layer of regulatory potential in translating the genome.
Project description:We describe Ribo Mega-SEC, a powerful approach for the separation and biochemical analysis of mammalian polysomes and ribosomal subunits using Size Exclusion Chromatography and uHPLC, which was achieved within 15 min from sample injection to fraction collection. Ribo Mega-SEC reproducibly shows translating ribosomes exist predominantly in polysome complexes in extracts isolated from human cell lines and mouse liver tissue, which alter in response to starvation. Ribo Mega-SEC provides a rapid, efficient, convenient and highly reproducible method for studying functional translation complexes and is easily combined with high-through put analysis such as proteomics and RNA-Seq, or with structural analysis using electron microscopy. We propose that Ribo Mega-SEC analysis is an accessible alternative to traditional polysome profiling using sucrose density gradients.
Project description:Charcot-Marie-Tooth (CMT) disease can be caused by mutations in Aminoacyl-tRNA-Synthetases, including G240R mutation in Glycyl-tRNA-Synthetase (GARS). Ribo-seq generates snapshots of translating ribosomes on mRNA and therefore allows analysis of ribosome pausing mRNA. Here we performed Ribo-seq on lysates of HEK293T cells overexpressing GARS, WT or G240R, to dissect mechanism of CMT linked with translation. We found that GARS G240R causes pausing of ribosomes with glycine codons in A-site. The effect is specific for 21 nt ribosome-protected fragments, produced by ribosomes with empty A-sites, suggestive of the deficit of charged Glycyl-tRNA in GARS G240R-CMT.
Project description:Ribosome profiling (Ribo-Seq) (maps positions of translating ribosomes on the transcriptome) and RNA-Seq (quantifies the transcriptome) analysis of equine torovirus.
Project description:Ribosome profiling (Ribo-Seq) (maps positions of translating ribosomes on the transcriptome) analysis of human (RD) cells infected with enterovirus strains EV7, EV71, and PV1.
Project description:RNA sequencing protocols allow for quantifying gene expression regulation at each individual step, from transcription to protein synthesis. Ribosome Profiling (Ribo-seq) maps the positions of translating ribosomes over the entire transcriptome. Despite its great potential, a rigorous statistical approach to identify translated regions from Ribo-seq data is not yet available. To fill this gap, we developed RiboTaper, which quantifies the significance of the three-nucleotide periodicity of Ribo-seq reads via spectral analysis methods. Examination of RNA fragments protected by ribosome
Project description:Ribosome profiling (Ribo-Seq) (maps positions of translating ribosomes on the transcriptome) and RNA-Seq (quantifies the transcriptome) analysis of African green monkey (Vero E6) cells and Aedes albopictus (C6/36) cells infected with Zika Virus (ZIKV) strain PE243. Cells were harvested at 24 h post infection (p.i.) and Ribo-Seq and RNA-Seq libraries were prepared and deep sequenced.
Project description:Ribosome profiling (Ribo-Seq) (maps positions of translating ribosomes on the transcriptome) and RNA-Seq (quantifies the transcriptome) analysis of Rattus norvegicus cells infected with Moloney Murine Leukemia Virus (Mo-MuLV).
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 (Ribo-Seq) (maps positions of translating ribosomes on the transcriptome) and RNA-Seq (quantifies the transcriptome) analysis of chicken (Gallus gallus) cells infected with Infectious Bronchitis Virus (IBV) strains Beaudette and M41.