Silencing of the ER and Integrative Stress Responses in the Liver of Mice with Error-Prone Translation

Translational errors frequently arise during protein synthesis, producing misfolded and dysfunctional proteins. Chronic stress resulting from translation errors may be particularly relevant in tissues that must synthesize and secrete large amounts of secretory proteins. Here, we studied the proteostasis networks in the liver of mice that express the Rps2-A226Y ribosomal ambiguity (ram) mutation to increase the translation error rate across all proteins. We found that Rps2-A226Y mice lack activation of the eIF2 kinase/ATF4 pathway, the main component of the integrated stress response (ISR), as well as the IRE1 and ATF6 pathways of the ER unfolded protein response (ER-UPR). Instead, we found downregulation of chronic ER stress responses, as indicated by reduced gene expression for lipogenic pathways and acute phase proteins, possibly via upregulation of Sirtuin-1. In parallel, we observed activation of alternative proteostasis responses, including the proteasome and the formation of stress granules. Together, our results point to a concerted response to error-prone translation to alleviate ER stress in favor of activating alternative proteostasis mechanisms, most likely to avoid cell damage and apoptotic pathways, which would result from persistent activation of the ER and integrated stress responses.

[1]  S. Frank,et al.  Random errors in protein synthesis activate an age-dependent program of muscle atrophy in mice , 2021, Communications biology.

[2]  P. Walter,et al.  The integrated stress response: From mechanism to disease , 2020, Science.

[3]  I. Dikic,et al.  Cellular quality control by the ubiquitin-proteasome system and autophagy , 2019, Science.

[4]  E. Westhof,et al.  Ribosomal mistranslation leads to silencing of the unfolded protein response and increased mitochondrial biogenesis , 2019, Communications Biology.

[5]  P. Khaitovich,et al.  Identification and Application of Gene Expression Signatures Associated with Lifespan Extension. , 2019, Cell metabolism.

[6]  Jonathan M. Mudge,et al.  Molecular complexity of the major urinary protein system of the Norway rat, Rattus norvegicus , 2018, Scientific Reports.

[7]  J. H. Lee,et al.  Systematic Characterization of Stress-Induced RNA Granulation. , 2018, Molecular cell.

[8]  D. Wasserman,et al.  The liver , 2017, Current Biology.

[9]  A. Fox,et al.  Nuclear bodies: news insights into structure and function. , 2017, Current opinion in cell biology.

[10]  A. Hyman,et al.  An aberrant phase transition of stress granules triggered by misfolded protein and prevented by chaperone function , 2017, The EMBO journal.

[11]  U. Stochaj,et al.  Cytoplasmic stress granules: Dynamic modulators of cell signaling and disease. , 2017, Biochimica et biophysica acta. Molecular basis of disease.

[12]  L. Florens,et al.  Cytosolic Proteostasis via Importing of Misfolded Proteins into Mitochondria , 2017, Nature.

[13]  D. Sinclair,et al.  SIRT1 protects the heart from ER stress-induced cell death through eIF2α deacetylation , 2016, Cell Death and Differentiation.

[14]  R. Kaufman,et al.  The role of ER stress in lipid metabolism and lipotoxicity , 2016, Journal of Lipid Research.

[15]  Andrew D. Rouillard,et al.  Enrichr: a comprehensive gene set enrichment analysis web server 2016 update , 2016, Nucleic Acids Res..

[16]  M. Nakao,et al.  Endoplasmic Reticulum (ER) Stress Induces Sirtuin 1 (SIRT1) Expression via the PI3K-Akt-GSK3β Signaling Pathway and Promotes Hepatocellular Injury* , 2015, The Journal of Biological Chemistry.

[17]  Eric Chevet,et al.  Proteostasis control by the unfolded protein response , 2015, Nature Cell Biology.

[18]  J. Bischofberger,et al.  Synaptic dysfunction, memory deficits and hippocampal atrophy due to ablation of mitochondrial fission in adult forebrain neurons , 2015, Cell Death and Differentiation.

[19]  Xiaolu Yang,et al.  A cellular system that degrades misfolded proteins and protects against neurodegeneration. , 2014, Molecular cell.

[20]  Y. Ye,et al.  Cleaning up in the endoplasmic reticulum: ubiquitin in charge , 2014, Nature Structural &Molecular Biology.

[21]  Weijun Luo,et al.  Pathview: an R/Bioconductor package for pathway-based data integration and visualization , 2013, Bioinform..

[22]  K. Duff,et al.  Contrasting Pathology of the Stress Granule Proteins TIA-1 and G3BP in Tauopathies , 2012, The Journal of Neuroscience.

[23]  Steven L Salzberg,et al.  Fast gapped-read alignment with Bowtie 2 , 2012, Nature Methods.

[24]  P. Walter,et al.  The Unfolded Protein Response: From Stress Pathway to Homeostatic Regulation , 2011, Science.

[25]  P. Robbins,et al.  SIRT1 associates with eIF2-alpha and regulates the cellular stress response , 2011, Scientific reports.

[26]  Colin N. Dewey,et al.  RSEM: accurate transcript quantification from RNA-Seq data with or without a reference genome , 2011, BMC Bioinformatics.

[27]  Randal J. Kaufman,et al.  Endoplasmic reticulum stress in liver disease. , 2011, Journal of hepatology.

[28]  L. Guarente,et al.  Hepatic overexpression of SIRT1 in mice attenuates endoplasmic reticulum stress and insulin resistance in the liver , 2011, FASEB journal : official publication of the Federation of American Societies for Experimental Biology.

[29]  Rachel Green,et al.  Hyperaccurate and error-prone ribosomes exploit distinct mechanisms during tRNA selection. , 2010, Molecular cell.

[30]  P. Puigserver,et al.  Conserved role of SIRT1 orthologs in fasting-dependent inhibition of the lipid/cholesterol regulator SREBP. , 2010, Genes & development.

[31]  G. Hotamisligil,et al.  Endoplasmic Reticulum Stress and the Inflammatory Basis of Metabolic Disease , 2010, Cell.

[32]  Z. Wang,et al.  ER stress negatively regulates AKT/TSC/mTOR pathway to enhance autophagy , 2010, Autophagy.

[33]  D. Sinclair,et al.  Mammalian sirtuins: biological insights and disease relevance. , 2010, Annual review of pathology.

[34]  R. Parker,et al.  Eukaryotic stress granules: the ins and outs of translation. , 2009, Molecular cell.

[35]  Davis J. McCarthy,et al.  edgeR: a Bioconductor package for differential expression analysis of digital gene expression data , 2009, Bioinform..

[36]  H. Saito,et al.  Formation of stress granules inhibits apoptosis by suppressing stress-responsive MAPK pathways , 2008, Nature Cell Biology.

[37]  Claus O. Wilke,et al.  Mistranslation-Induced Protein Misfolding as a Dominant Constraint on Coding-Sequence Evolution , 2008, Cell.

[38]  D. Ron,et al.  Dephosphorylation of translation initiation factor 2alpha enhances glucose tolerance and attenuates hepatosteatosis in mice. , 2008, Cell metabolism.

[39]  Tomomi Gotoh,et al.  ER Stress Triggers Apoptosis by Activating BH3-Only Protein Bim , 2007, Cell.

[40]  L. Scorrano,et al.  Organelle isolation: functional mitochondria from mouse liver, muscle and cultured filroblasts , 2007, Nature Protocols.

[41]  A. Cooper,et al.  Misfolded proteins traffic from the endoplasmic reticulum (ER) due to ER export signals. , 2006, Molecular biology of the cell.

[42]  J. Lefkowitch Special stains in diagnostic liver pathology. , 2006, Seminars in diagnostic pathology.

[43]  V. Ramakrishnan,et al.  First published online as a Review in Advance on February 25, 2005 STRUCTURAL INSIGHTS INTO TRANSLATIONAL , 2022 .

[44]  Joon-No Lee,et al.  Proteolytic Activation of Sterol Regulatory Element-binding Protein Induced by Cellular Stress through Depletion of Insig-1* , 2004, Journal of Biological Chemistry.

[45]  Juno Choe,et al.  Protein tolerance to random amino acid change. , 2004, Proceedings of the National Academy of Sciences of the United States of America.

[46]  M. Rodnina,et al.  Kinetic determinants of high-fidelity tRNA discrimination on the ribosome. , 2004, Molecular cell.

[47]  R. Paules,et al.  An integrated stress response regulates amino acid metabolism and resistance to oxidative stress. , 2003, Molecular cell.

[48]  R. Kaufman,et al.  The mammalian unfolded protein response. , 2003, Annual review of biochemistry.

[49]  Joseph L Goldstein,et al.  SREBPs: activators of the complete program of cholesterol and fatty acid synthesis in the liver. , 2002, The Journal of clinical investigation.

[50]  M. Hipp,et al.  Functional Modules of the Proteostasis Network. , 2019, Cold Spring Harbor perspectives in biology.

[51]  R. Sauer,et al.  Genetic analysis of protein stability and function. , 1989, Annual review of genetics.