Reflux of Endoplasmic Reticulum proteins to the cytosol yields inactivation of tumor suppressors
Ontology highlight
ABSTRACT:
INSTRUMENT(S): LTQ Orbitrap Elite
ORGANISM(S): Homo Sapiens (human)
TISSUE(S): Cell Suspension Culture, Permanent Cell Line Cell, Glioblastoma Multiforme Cell
DISEASE(S): Brain Cancer
SUBMITTER: 
Luc Negroni
LAB HEAD: Eric Chevet
PROVIDER: PXD023567 | Pride | 2021-05-03
REPOSITORIES: Pride
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Project description:In eukaryotic cells, the spatial regulation of protein expression is frequently conferred through the coupling of mRNA localization and the local control of translation. mRNA localization to the endoplasmic reticulum (ER) is a prominent example of such regulation and serves a ubiquitous role in segregating the synthesis of secretory and integral membrane proteins to the ER. Recent genomic and biochemical studies have now expanded this view to suggest a role for the ER in global protein synthesis. We have utilized cell fractionation and ribosome profiling to obtain a genomic survey of the subcellular organization of mRNA translation and report that ribosomal loading of mRNAs, a proxy for mRNA translation, is biased to the ER. Notably, ER-associated mRNAs encoding both cytosolic and topogenic signal-encoding proteins display similar ribosome loading densities, suggesting that ER-associated ribosomes serve a global role in mRNA translation. We propose that the partitioning of mRNAs and their translation between the cytosol and ER compartments may represent a novel mechanism for the post-transcriptional regulation of gene expression.
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