Project description:Ribosome profiling (RiboSeq) maps positions of translating ribosomes on the transcriptome. Here we optimized ribosome profiling for footprinting mitochondrial ribosomes, and profiled three human cell-lines - HEK293, a PDE12-/- knockout, and a deltaFLP 143B cybrid.
Project description:Ribosome profiling and RNAseq data on human BJ fibroblasts and cybrid cells using an adapted ribosome profiling protocol to improve detection of mitochondrial ribosome protected fragments 51-base length single read ribosome profiling data on human fibroblasts and cybrid cells using an adapted ribosome profiling protocol; and 51-base length single read RNAseq on polyA enriched RNA
Project description:Ribosome profiling and RNAseq data on human BJ fibroblasts and cybrid cells using an adapted ribosome profiling protocol to improve detection of mitochondrial ribosome protected fragments
Project description:Efficient mitochondrial function is required in tissues with high energy demand such as the heart, and mitochondrial dysfunction is associated with cardiovascular disease. Expression of mitochondrial proteins is tightly regulated in response to internal and external stimuli. Here we identify a novel mechanism regulating mitochondrial content and function, through BUD23-dependent ribosome generation. BUD23 was required for ribosome maturation, normal 18S/28S stoichiometry and modulated the translation of mitochondrial transcripts in human A549 cells.
Project description:The biogenesis of nearly all mitochondrial proteins begins with translation on cytosolic ribosomes. How these proteins are subsequently delivered to mitochondria remains poorly understood. Here, we systematically investigated the coupling of mitochondrial protein translation and import using selective ribosome profiling in human cells. Cotranslational targeting requires an N-terminal presequence on the nascent protein and contributes to mRNA localization at the mitochondrial surface. This pathway is predominantly used by large, multidomain and topologically complex proteins, whose import efficiency is enhanced when targeted cotranslationally. In contrast to protein targeting to the endoplasmic reticulum (ER), cotranslational mitochondrial import does not favor membrane proteins and initiates late during translation, specifically upon the exposure of a complex globular fold in the nascent protein. Our findings reveal a multi-layered protein sorting system that recognizes both the targeting signal and protein folding status during translation.
Project description:Nearly all mitochondrial proteins are nuclear-encoded and are targeted to their mitochondrial destination from the cytosol. Here, we used proximity-specific ribosome profiling to comprehensively measure translation at the mitochondrial surface in yeast. The majority of inner membrane proteins were co-translationally targeted to mitochondria, reminiscent of proteins entering the endoplasmic reticulum (ER). Comparison between mitochondrial and ER localization demonstrated that the vast majority of proteins were targeted to a specific organelle. A prominent exception was the fumarate reductase Osm1, known to reside in mitochondria. We identified a conserved ER isoform of Osm1, which contributes to the oxidative protein folding capacity of the organelle. This dual localization was enabled by alternative translation initiation sites encoding distinct targeting signals. These findings highlight the exquisite in vivo specificity of organellar targeting mechanisms.