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Dabsan S, Twito G, Biadsy S, Igbaria A. Less is better: various means to reduce protein load in the endoplasmic reticulum. FEBS J 2025; 292:976-989. [PMID: 38865586 PMCID: PMC11880973 DOI: 10.1111/febs.17201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2023] [Revised: 04/08/2024] [Accepted: 06/05/2024] [Indexed: 06/14/2024]
Abstract
The endoplasmic reticulum (ER) is an important organelle that controls the intracellular and extracellular environments. The ER is responsible for folding almost one-third of the total protein population in the eukaryotic cell. Disruption of ER-protein folding is associated with numerous human diseases, including metabolic disorders, neurodegenerative diseases, and cancer. During ER perturbations, the cells deploy various mechanisms to increase the ER-folding capacity and reduce ER-protein load by minimizing the number of substrates entering the ER to regain homeostasis. These mechanisms include signaling pathways, degradation mechanisms, and other processes that mediate the reflux of ER content to the cytosol. In this review, we will discuss the recent discoveries of five different ER quality control mechanisms, including the unfolded protein response (UPR), ER-associated-degradation (ERAD), pre-emptive quality control, ER-phagy and ER to cytosol signaling (ERCYS). We will discuss the roles of these processes in decreasing ER-protein load and inter-mechanism crosstalk.
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Affiliation(s)
- Salam Dabsan
- Department of Life SciencesBen‐Gurion University of the NegevBeer ShevaIsrael
| | - Gal Twito
- Department of Life SciencesBen‐Gurion University of the NegevBeer ShevaIsrael
| | - Suma Biadsy
- Department of Life SciencesBen‐Gurion University of the NegevBeer ShevaIsrael
| | - Aeid Igbaria
- Department of Life SciencesBen‐Gurion University of the NegevBeer ShevaIsrael
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2
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Shukla N, Neal ML, Farré JC, Mast FD, Truong L, Simon T, Miller LR, Aitchison JD, Subramani S. TOR and heat shock response pathways regulate peroxisome biogenesis during proteotoxic stress. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2025:2024.12.31.630809. [PMID: 40093121 PMCID: PMC11908190 DOI: 10.1101/2024.12.31.630809] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 03/19/2025]
Abstract
Peroxisomes are versatile organelles mediating energy homeostasis and redox balance. While peroxisome dysfunction is linked to numerous diseases, the molecular mechanisms and signaling pathways regulating peroxisomes during cellular stress remain elusive. Using yeast, we show that perturbations disrupting protein homeostasis including loss of ER or cytosolic chaperone function, impairments in ER protein translocation, blocking ER N-glycosylation, or reductive stress, cause peroxisome proliferation. This proliferation is driven by increased de novo biogenesis from the ER as well as increased fission of pre-existing peroxisomes, rather than impaired pexophagy. Notably, peroxisome biogenesis is essential for cellular recovery from proteotoxic stress. Through comprehensive testing of major signaling pathways, we determine this response to be mediated by activation of the heat shock response and inhibition of Target of Rapamycin (TOR) signaling. Finally, the effects of proteotoxic stress and TOR inhibition on peroxisomes are also captured in human fibroblasts. Overall, our findings reveal a critical and conserved role of peroxisomes in cellular response to proteotoxic stress.
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Affiliation(s)
- Nandini Shukla
- Department of Molecular Biology, School of Biological Sciences, University of California, San Diego, La Jolla, CA, USA
| | - Maxwell L Neal
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, WA, USA
| | - Jean-Claude Farré
- Department of Molecular Biology, School of Biological Sciences, University of California, San Diego, La Jolla, CA, USA
| | - Fred D Mast
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, WA, USA
- Department of Pediatrics, University of Washington, Seattle, WA, USA
| | - Linh Truong
- Department of Molecular Biology, School of Biological Sciences, University of California, San Diego, La Jolla, CA, USA
| | - Theresa Simon
- Department of Molecular Biology, School of Biological Sciences, University of California, San Diego, La Jolla, CA, USA
| | - Leslie R Miller
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, WA, USA
| | - John D Aitchison
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, WA, USA
- Department of Pediatrics, University of Washington, Seattle, WA, USA
- Department of Biochemistry, University of Washington, Seattle, WA, USA
| | - Suresh Subramani
- Department of Molecular Biology, School of Biological Sciences, University of California, San Diego, La Jolla, CA, USA
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3
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Menéndez-Coto N, Garcia-Gonzalez C, Baena-Huerta FJ, Zapata-Pérez R, Rabadán-Ros R, Núñez-Delicado E, González-Llorente L, Caso-Peláez E, Coto-Montes A. Combining Cold Atmospheric Plasma and Environmental Nanoparticle Removal Device Reduces Neurodegenerative Markers. Int J Mol Sci 2024; 25:12986. [PMID: 39684696 DOI: 10.3390/ijms252312986] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2024] [Revised: 11/27/2024] [Accepted: 11/30/2024] [Indexed: 12/18/2024] Open
Abstract
Ageing leads to a gradual deterioration of the organs, with the brain being particularly susceptible, often leading to neurodegeneration. This process includes well-known changes such as tau hyperphosphorylation and beta-amyloid deposition, which are commonly associated with neurodegenerative diseases but are also present in ageing. These structures are triggered by earlier cellular changes such as energy depletion and impaired protein synthesis, both of which are essential for cell function. These changes may in part be induced by environmental pollution, which has been shown to accelerate these processes. Cold Atmospheric Plasma (CAP) or atmospheric pressure gas discharge plasmas have shown promise in activating the immune system and improving cellular function in vitro, although their effects at the organ level remain poorly understood. Our aim in this work is to investigate the effect of a device that combines CAP treatment with the effective removal of environmental nanoparticles, typical products of pollution, on the activity of aged mouse brains. The results showed an increase in energy capacity, a reduction in reticulum stress and an activation of cellular autophagic clearance, minimising aggresomes in the brain. This leads to a reduction in key markers of neurodegeneration such as tau hyperphosphorylation and beta-amyloid deposition, demonstrating the efficacy of the tested product at the brain level.
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Affiliation(s)
- Nerea Menéndez-Coto
- Department of Morphology and Cell Biology, University of Oviedo, 33006 Oviedo, Spain
- Research Group Oxidative Stress Knowledge and Advanced Research (OSKAR), Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), 33011 Oviedo, Spain
- Instituto de Neurociencias del Principado de Asturias (INEUROPA), 33006 Oviedo, Spain
| | - Claudia Garcia-Gonzalez
- Department of Morphology and Cell Biology, University of Oviedo, 33006 Oviedo, Spain
- Research Group Oxidative Stress Knowledge and Advanced Research (OSKAR), Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), 33011 Oviedo, Spain
- Instituto de Neurociencias del Principado de Asturias (INEUROPA), 33006 Oviedo, Spain
| | | | - Rubén Zapata-Pérez
- UCAM HiTech Sport & Health Innovation Hub, Universidad Católica de Murcia, Guadalupe de Maciascoque, 30107 Murcia, Spain
| | - Rubén Rabadán-Ros
- UCAM HiTech Sport & Health Innovation Hub, Universidad Católica de Murcia, Guadalupe de Maciascoque, 30107 Murcia, Spain
| | - Estrella Núñez-Delicado
- Departamento de Ciencias de la Salud, Universidad Católica San Antonio de Murcia (UCAM), Avenida de los Jerónimos s/n, Guadalupe de Maciascoque, 30107 Murcia, Spain
| | - Lucía González-Llorente
- UCAM HiTech Sport & Health Innovation Hub, Universidad Católica de Murcia, Guadalupe de Maciascoque, 30107 Murcia, Spain
- System and Precision Medicine, Hospital Covadonga, 33204 Gijón, Spain
| | - Enrique Caso-Peláez
- UCAM HiTech Sport & Health Innovation Hub, Universidad Católica de Murcia, Guadalupe de Maciascoque, 30107 Murcia, Spain
- System and Precision Medicine, Hospital Covadonga, 33204 Gijón, Spain
| | - Ana Coto-Montes
- Department of Morphology and Cell Biology, University of Oviedo, 33006 Oviedo, Spain
- Research Group Oxidative Stress Knowledge and Advanced Research (OSKAR), Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), 33011 Oviedo, Spain
- Instituto de Neurociencias del Principado de Asturias (INEUROPA), 33006 Oviedo, Spain
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4
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Ishida-Ishihara S, Yaguchi K, Miura S, Nomura R, Wang Q, Yoshizawa K, Sato K, Yang G, Veszelyi K, Banhegyi G, Margittai E, Uehara R. Fragility of ER homeostatic regulation underlies haploid instability in human somatic cells. J Biol Chem 2024; 300:107909. [PMID: 39433129 DOI: 10.1016/j.jbc.2024.107909] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2024] [Revised: 09/29/2024] [Accepted: 10/08/2024] [Indexed: 10/23/2024] Open
Abstract
Mammalian somatic cells are generally unstable in the haploid state, resulting in haploid-to-diploid conversion within a short time frame. However, cellular and molecular principles that limit the sustainability of somatic haploidy remain unknown. In this study, we found the haploidy-linked vulnerability to endoplasmic reticulum (ER) stress as a critical cause of haploid intolerance in human somatic cells. Pharmacological induction of ER stress selectively induced apoptosis in haploid cells, facilitating the replacement of haploids by coexisting diploidized cells in a caspase-dependent manner. Biochemical analyses revealed that unfolded protein response (UPR) was activated with similar dynamics between haploids and diploids upon ER stress induction. However, haploids were less efficient in solving proteotoxic stress, resulting in a bias toward a proapoptotic mode of UPR signaling. Artificial replenishment of chaperone function substantially alleviated the haploidy-linked upregulation of proapoptotic signaling and improved haploid cell retention under tunicamycin-induced ER stress. These data demonstrate that the ER stress-driven haploid instability stems from inefficient proteostatic control that alters the functionality of UPR to cause apoptosis selectively in haploids. Interestingly, haploids suffered a higher level of protein aggregation even in unperturbed conditions, and the long-term stability of the haploid state was significantly improved by alleviating their natural proteotoxicity. Based on these results, we propose that the haploidy-specific vulnerability to ER stress creates a fundamental cause of haploid intolerance in mammalian somatic cells. Our findings provide new insight into the principle that places a stringent restriction on the evolution of animal life cycles.
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Affiliation(s)
- Sumire Ishida-Ishihara
- Graduate School of Life Science, Hokkaido University, Sapporo, Japan; Faculty of Advanced Life Science, Hokkaido University, Sapporo, Japan
| | - Kan Yaguchi
- Graduate School of Life Science, Hokkaido University, Sapporo, Japan; Faculty of Advanced Life Science, Hokkaido University, Sapporo, Japan
| | - Sena Miura
- Graduate School of Life Science, Hokkaido University, Sapporo, Japan
| | - Ryoto Nomura
- Graduate School of Life Science, Hokkaido University, Sapporo, Japan
| | - QiJiao Wang
- Graduate School of Life Science, Hokkaido University, Sapporo, Japan
| | - Koya Yoshizawa
- Graduate School of Life Science, Hokkaido University, Sapporo, Japan
| | - Kimino Sato
- Graduate School of Life Science, Hokkaido University, Sapporo, Japan
| | - Guang Yang
- Graduate School of Life Science, Hokkaido University, Sapporo, Japan
| | - Krisztina Veszelyi
- Institute of Translational Medicine, Semmelweis University, Budapest, Hungary
| | - Gabor Banhegyi
- Institute of Biochemistry and Molecular Biology, Semmelweis University, Budapest, Hungary
| | - Eva Margittai
- Institute of Translational Medicine, Semmelweis University, Budapest, Hungary
| | - Ryota Uehara
- Graduate School of Life Science, Hokkaido University, Sapporo, Japan; Faculty of Advanced Life Science, Hokkaido University, Sapporo, Japan.
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5
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Zalon AJ, Quiriconi DJ, Pitcairn C, Mazzulli JR. α-Synuclein: Multiple pathogenic roles in trafficking and proteostasis pathways in Parkinson's disease. Neuroscientist 2024; 30:612-635. [PMID: 38420922 PMCID: PMC11358363 DOI: 10.1177/10738584241232963] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/02/2024]
Abstract
Parkinson's disease (PD) is a common age-related neurodegenerative disorder characterized by the loss of dopaminergic neurons in the midbrain. A hallmark of both familial and sporadic PD is the presence of Lewy body inclusions composed mainly of aggregated α-synuclein (α-syn), a presynaptic protein encoded by the SNCA gene. The mechanisms driving the relationship between α-syn accumulation and neurodegeneration are not completely understood, although recent evidence indicates that multiple branches of the proteostasis pathway are simultaneously perturbed when α-syn aberrantly accumulates within neurons. Studies from patient-derived midbrain cultures that develop α-syn pathology through the endogenous expression of PD-causing mutations show that proteostasis disruption occurs at the level of synthesis/folding in the endoplasmic reticulum (ER), downstream ER-Golgi trafficking, and autophagic-lysosomal clearance. Here, we review the fundamentals of protein transport, highlighting the specific steps where α-syn accumulation may intervene and the downstream effects on proteostasis. Current therapeutic efforts are focused on targeting single pathways or proteins, but the multifaceted pathogenic role of α-syn throughout the proteostasis pathway suggests that manipulating several targets simultaneously will provide more effective disease-modifying therapies for PD and other synucleinopathies.
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Affiliation(s)
- Annie J Zalon
- The Ken and Ruth Davee Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Drew J Quiriconi
- The Ken and Ruth Davee Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Caleb Pitcairn
- The Ken and Ruth Davee Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Joseph R Mazzulli
- The Ken and Ruth Davee Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
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6
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Ernst R, Renne MF, Jain A, von der Malsburg A. Endoplasmic Reticulum Membrane Homeostasis and the Unfolded Protein Response. Cold Spring Harb Perspect Biol 2024; 16:a041400. [PMID: 38253414 PMCID: PMC11293554 DOI: 10.1101/cshperspect.a041400] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
The endoplasmic reticulum (ER) is the key organelle for membrane biogenesis. Most lipids are synthesized in the ER, and most membrane proteins are first inserted into the ER membrane before they are transported to their target organelle. The composition and properties of the ER membrane must be carefully controlled to provide a suitable environment for the insertion and folding of membrane proteins. The unfolded protein response (UPR) is a powerful signaling pathway that balances protein and lipid production in the ER. Here, we summarize our current knowledge of how aberrant compositions of the ER membrane, referred to as lipid bilayer stress, trigger the UPR.
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Affiliation(s)
- Robert Ernst
- Medical Biochemistry and Molecular Biology, Medical Faculty, Saarland University, 66421 Homburg, Germany
- Preclinical Center for Molecular Signaling (PZMS), Medical Faculty, Saarland University, 66421 Homburg, Germany
| | - Mike F Renne
- Medical Biochemistry and Molecular Biology, Medical Faculty, Saarland University, 66421 Homburg, Germany
- Preclinical Center for Molecular Signaling (PZMS), Medical Faculty, Saarland University, 66421 Homburg, Germany
| | - Aamna Jain
- Medical Biochemistry and Molecular Biology, Medical Faculty, Saarland University, 66421 Homburg, Germany
- Preclinical Center for Molecular Signaling (PZMS), Medical Faculty, Saarland University, 66421 Homburg, Germany
| | - Alexander von der Malsburg
- Medical Biochemistry and Molecular Biology, Medical Faculty, Saarland University, 66421 Homburg, Germany
- Preclinical Center for Molecular Signaling (PZMS), Medical Faculty, Saarland University, 66421 Homburg, Germany
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7
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Pastor-Cantizano N, Angelos ER, Ruberti C, Jiang T, Weng X, Reagan BC, Haque T, Juenger TE, Brandizzi F. Programmed cell death regulator BAP2 is required for IRE1-mediated unfolded protein response in Arabidopsis. Nat Commun 2024; 15:5804. [PMID: 38987268 PMCID: PMC11237027 DOI: 10.1038/s41467-024-50105-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Accepted: 06/29/2024] [Indexed: 07/12/2024] Open
Abstract
Environmental and physiological situations can challenge the balance between protein synthesis and folding capacity of the endoplasmic reticulum (ER) and cause ER stress, a potentially lethal condition. The unfolded protein response (UPR) restores ER homeostasis or actuates programmed cell death (PCD) when ER stress is unresolved. The cell fate determination mechanisms of the UPR are not well understood, especially in plants. Here, we integrate genetics and ER stress profiling with natural variation and quantitative trait locus analysis of 350 natural accessions of the model species Arabidopsis thaliana. Our analyses implicate a single nucleotide polymorphism to the loss of function of the general PCD regulator BON-ASSOCIATED PROTEIN2 (BAP2) in UPR outcomes. We establish that ER stress-induced BAP2 expression is antagonistically regulated by the UPR master regulator, inositol-requiring enzyme 1 (IRE1), and that BAP2 controls adaptive UPR amplitude in ER stress and ignites pro-death mechanisms in conditions of UPR insufficiency.
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Affiliation(s)
- Noelia Pastor-Cantizano
- MSU-DOE Plant Research Lab, Michigan State University, East Lansing, MI, USA
- Department of Biochemistry and Molecular Biology, Institute for Biotechnology and Biomedicine (BIOTECMED), University of Valencia, Burjassot, Spain
| | - Evan R Angelos
- MSU-DOE Plant Research Lab, Michigan State University, East Lansing, MI, USA
- Botany & Plant Sciences Department, Institute for Integrative Genome Biology, University of California Riverside, Riverside, CA, USA
| | - Cristina Ruberti
- MSU-DOE Plant Research Lab, Michigan State University, East Lansing, MI, USA
- Department of Biosciences, University of Milan, Milano, Italy
| | - Tao Jiang
- MSU-DOE Plant Research Lab, Michigan State University, East Lansing, MI, USA
- Mid-Florida Research and Education Center, University of Florida, Apopka, FL, USA
| | - Xiaoyu Weng
- Department of Integrative Biology, University of Texas, Austin, TX, USA
| | - Brandon C Reagan
- MSU-DOE Plant Research Lab, Michigan State University, East Lansing, MI, USA
| | - Taslima Haque
- Department of Integrative Biology, University of Texas, Austin, TX, USA
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI, USA
| | - Thomas E Juenger
- Department of Integrative Biology, University of Texas, Austin, TX, USA
| | - Federica Brandizzi
- MSU-DOE Plant Research Lab, Michigan State University, East Lansing, MI, USA.
- Plant Biology Department, Michigan State University, East Lansing, MI, USA.
- Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, MI, USA.
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8
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Nair KA, Liu B. Navigating the landscape of the unfolded protein response in CD8 + T cells. Front Immunol 2024; 15:1427859. [PMID: 39026685 PMCID: PMC11254671 DOI: 10.3389/fimmu.2024.1427859] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2024] [Accepted: 06/24/2024] [Indexed: 07/20/2024] Open
Abstract
Endoplasmic reticulum stress occurs due to large amounts of misfolded proteins, hypoxia, nutrient deprivation, and more. The unfolded protein is a complex intracellular signaling network designed to operate under this stress. Composed of three individual arms, inositol-requiring enzyme 1, protein kinase RNA-like ER kinase, and activating transcription factor-6, the unfolded protein response looks to resolve stress and return to proteostasis. The CD8+ T cell is a critical cell type for the adaptive immune system. The unfolded protein response has been shown to have a wide-ranging spectrum of effects on CD8+ T cells. CD8+ T cells undergo cellular stress during activation and due to environmental insults. However, the magnitude of the effects this response has on CD8+ T cells is still understudied. Thus, studying these pathways is important to unraveling the inner machinations of these powerful cells. In this review, we will highlight the recent literature in this field, summarize the three pathways of the unfolded protein response, and discuss their roles in CD8+ T cell biology and functionality.
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Affiliation(s)
- Keith Alan Nair
- Division of Hematology, Department of Internal Medicine, The Ohio State University Comprehensive Cancer Center, Columbus, OH, United States
- The Pelotonia Institute for Immuno-Oncology, The Ohio State University Comprehensive Cancer Center, Columbus, OH, United States
| | - Bei Liu
- Division of Hematology, Department of Internal Medicine, The Ohio State University Comprehensive Cancer Center, Columbus, OH, United States
- The Pelotonia Institute for Immuno-Oncology, The Ohio State University Comprehensive Cancer Center, Columbus, OH, United States
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9
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Liu S, Yin Y, Liu S, Wang C, Sun W, Hu X. Shining a light on liver health: advancements in fluorescence-enhanced enzyme biosensors for early disease detection. Front Bioeng Biotechnol 2024; 12:1392857. [PMID: 38707500 PMCID: PMC11066187 DOI: 10.3389/fbioe.2024.1392857] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2024] [Accepted: 04/05/2024] [Indexed: 05/07/2024] Open
Abstract
Early detection of liver diseases holds paramount importance in optimizing treatment outcomes and prognosis, thereby significantly enhancing the likelihood of recovery while mitigating the risk of progression to liver cancer. Liver diseases encompass a spectrum of conditions, each potentially manifesting distinct enzymatic profiles. Monitoring these enzymes in situ facilitates timely intervention and therapeutic management. In recent years, the field of biosensor technology has witnessed remarkable advancement, owing to strides in biomedicine and computational sciences. Biosensors have garnered widespread utility across medical and biological domains, spanning the detection of disease biomarkers, drug release tracking, ion imaging, and fluorescence imaging within living organisms. These applications have markedly enhanced imaging resolution and have the potential to refine disease diagnosis accuracy for clinicians. A pivotal aspect in the successful application of this technology lies in the construction of fluorescence probes adept at swiftly and selectively identifying target enzymes by amalgamating liver disease enzymes with fluorescence probe technology. However, research in this niche area remains relatively scarce. Building upon this foundational understanding, the present review delineates the utilization of biosensors in the early diagnosis of liver disease. Serving as a theoretical framework, this review envisages the development of high-performance biosensors tailored for the early detection of liver cancer. Furthermore, it offers insights into the potential of biosensor technology to progress and broaden its practical applications, thus contributing to the advancement of diagnostic methodologies in liver disease management.
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Affiliation(s)
- Shifeng Liu
- Department of the Interventional Medical Center, the Affiliated Hospital of Qingdao University, Qingdao, China
| | - Yatong Yin
- Qingdao Maternal and Child Health and Family Planning Service Center, Qingdao, China
| | - Shihai Liu
- Medical Research Center, The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Congxiao Wang
- Department of the Interventional Medical Center, the Affiliated Hospital of Qingdao University, Qingdao, China
| | - Wenshe Sun
- Qingdao Cancer Institute, Qingdao University, Qingdao, China
| | - Xiaokun Hu
- Department of the Interventional Medical Center, the Affiliated Hospital of Qingdao University, Qingdao, China
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10
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Neidhardt L, Cloots E, Friemel N, Weiss CAM, Harding HP, McLaughlin SH, Janssens S, Ron D. The IRE1β-mediated unfolded protein response is repressed by the chaperone AGR2 in mucin producing cells. EMBO J 2024; 43:719-753. [PMID: 38177498 PMCID: PMC10907699 DOI: 10.1038/s44318-023-00014-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Revised: 11/07/2023] [Accepted: 11/15/2023] [Indexed: 01/06/2024] Open
Abstract
Effector mechanisms of the unfolded protein response (UPR) in the endoplasmic reticulum (ER) are well-characterised, but how ER proteostasis is sensed is less well understood. Here, we exploited the beta isoform of the UPR transducer IRE1, that is specific to mucin-producing cells in order to gauge the relative regulatory roles of activating ligands and repressing chaperones of the specialised ER of goblet cells. Replacement of the stress-sensing luminal domain of endogenous IRE1α in CHO cells (normally expressing neither mucin nor IRE1β) with the luminal domain of IRE1β deregulated basal IRE1 activity. The mucin-specific chaperone AGR2 repressed IRE1 activity in cells expressing the domain-swapped IRE1β/α chimera, but had no effect on IRE1α. Introduction of the goblet cell-specific client MUC2 reversed AGR2-mediated repression of the IRE1β/α chimera. In vitro, AGR2 actively de-stabilised the IRE1β luminal domain dimer and formed a reversible complex with the inactive monomer. These features of the IRE1β-AGR2 couple suggest that active repression of IRE1β by a specialised mucin chaperone subordinates IRE1 activity to a proteostatic challenge unique to goblet cells, a challenge that is otherwise poorly recognised by the pervasive UPR transducers.
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Affiliation(s)
- Lisa Neidhardt
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, CB2 0XY, UK.
| | - Eva Cloots
- Laboratory for ER stress and Inflammation, VIB Center for Inflammation Research, Technologiepark-Zwijnaarde 71, 9052, Ghent, Belgium
- Department of Pediatrics and Internal Medicine, Faculty of Medicine and Health Sciences, Ghent University, Technologiepark-Zwijnaarde 71, 9052, Ghent, Belgium
| | - Natalie Friemel
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, CB2 0XY, UK
| | - Caroline A M Weiss
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, CB2 0XY, UK
| | - Heather P Harding
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, CB2 0XY, UK
| | - Stephen H McLaughlin
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge, CB2 0QH, UK
| | - Sophie Janssens
- Laboratory for ER stress and Inflammation, VIB Center for Inflammation Research, Technologiepark-Zwijnaarde 71, 9052, Ghent, Belgium
- Department of Pediatrics and Internal Medicine, Faculty of Medicine and Health Sciences, Ghent University, Technologiepark-Zwijnaarde 71, 9052, Ghent, Belgium
| | - David Ron
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, CB2 0XY, UK.
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11
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Groenendyk J, Michalak M. Interplay between calcium and endoplasmic reticulum stress. Cell Calcium 2023; 113:102753. [PMID: 37209448 DOI: 10.1016/j.ceca.2023.102753] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Revised: 05/05/2023] [Accepted: 05/06/2023] [Indexed: 05/22/2023]
Abstract
Cellular homeostasis is crucial for the healthy functioning of the organism. Disruption of cellular homeostasis activates endoplasmic reticulum (ER) stress coping responses including the unfolded protein response (UPR). There are three ER resident stress sensors responsible for UPR activation - IRE1α, PERK and ATF6. Ca2+ signaling plays an important role in stress responses including the UPR and the ER is the main Ca2+ storage organelle and a source of Ca2+ for cell signaling. The ER contains many proteins involved in Ca2+ import/export/ storage, Ca2+ movement between different cellular organelles and ER Ca2+ stores refilling. Here we focus on selected aspects of ER Ca2+ homeostasis and its role in activation of the ER stress coping responses.
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Affiliation(s)
- Jody Groenendyk
- Department of Biochemistry, University of Alberta, Edmonton, AB T6G 2H7, Canada.
| | - Marek Michalak
- Department of Biochemistry, University of Alberta, Edmonton, AB T6G 2H7, Canada.
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Lin Y, Feng Y, Zheng L, Zhao M, Huang M. Improved protein production in yeast using cell engineering with genes related to a key factor in the unfolded protein response. Metab Eng 2023; 77:152-161. [PMID: 37044356 DOI: 10.1016/j.ymben.2023.04.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Revised: 04/08/2023] [Accepted: 04/09/2023] [Indexed: 04/14/2023]
Abstract
The yeast Saccharomyces cerevisiae is a widely used cell factory for protein production. Increasing the protein production capacity of a yeast strain may be beneficial for obtaining recombinant proteins as a product or exerting its competence in consolidated bioprocessing. However, heterologous protein expression usually imposes stress on cells. Improving the cell's ability to cope with stress enhances protein yield. HAC1 is a key transcription factor in the unfolded protein response (UPR). In this study, several genes related to the UPR signal pathway, including unfolded protein sensing, HAC1 mRNA splicing, mRNA ligation, mRNA decay, translation, and Hac1p degradation, were selected as targets to engineer yeast strains. The final engineered strain produced α-amylase 3.3-fold, and human serum albumin 15.3-fold, greater than that of the control strain. Key regulation and metabolic network changes in the engineered strains were identified by transcriptome analysis and physiological characterizations. This study demonstrated that cell engineering with genes relevant to the key node HAC1 in UPR increased protein secretion substantially. The verified genetic modifications of this study provide useful targets in the construction of yeast cell factories for efficient protein production.
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Affiliation(s)
- Yeping Lin
- School of Food Science and Engineering, South China University of Technology, Guangzhou, 510641, China; Guangdong Food Green Processing and Nutrition Regulation Technologies Research Center, Guangzhou, 510650, China
| | - Yunzi Feng
- School of Food Science and Engineering, South China University of Technology, Guangzhou, 510641, China; Guangdong Food Green Processing and Nutrition Regulation Technologies Research Center, Guangzhou, 510650, China
| | - Lin Zheng
- School of Food Science and Engineering, South China University of Technology, Guangzhou, 510641, China; Guangdong Food Green Processing and Nutrition Regulation Technologies Research Center, Guangzhou, 510650, China
| | - Mouming Zhao
- School of Food Science and Engineering, South China University of Technology, Guangzhou, 510641, China; Guangdong Food Green Processing and Nutrition Regulation Technologies Research Center, Guangzhou, 510650, China
| | - Mingtao Huang
- School of Food Science and Engineering, South China University of Technology, Guangzhou, 510641, China; Guangdong Food Green Processing and Nutrition Regulation Technologies Research Center, Guangzhou, 510650, China.
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13
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Du J, Zhao H, Zhu M, Dong Y, Peng L, Li J, Zhao Q, Yu Q, Li M. Atg8 and Ire1 in combination regulate the autophagy-related endoplasmic reticulum stress response in Candida albicans. Res Microbiol 2023; 174:103996. [PMID: 36328097 DOI: 10.1016/j.resmic.2022.103996] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Revised: 10/24/2022] [Accepted: 10/26/2022] [Indexed: 11/05/2022]
Abstract
The unfolded protein response (UPR) is an important pathway to prevent endoplasmic reticulum (ER) stress in eukaryotic cells. In Saccharomyces cerevisiae, Ire1 is a key regulatory factor required for HAC1 gene splicing for further production of functional Hac1 and activation of UPR gene expression. Autophagy is another mechanism involved in the attenuation of ER stress by ER-phagy, and Atg8 is a core protein in autophagy. Both autophagy and UPR are critical for ER stress response, but whether they act individually or in combination in Candida albicans is unknown. In this study, we explored the interaction between Ire1 and the autophagy protein Atg8 for the ER stress response by constructing the atg8Δ/Δire1Δ/Δ double mutant in the pathogenic fungus C. albicans. Compared to the single mutants atg8Δ/Δ or ire1Δ/Δ, atg8Δ/Δire1Δ/Δ exhibited much higher sensitivity to various ER stress-inducing agents and more severe attenuation of UPR gene expression under ER stress. Further investigations showed that the double mutant had a defect in ER-phagy, which was associated with attenuated vacuolar fusion under ER stress. This study revealed that Ire1 and Atg8 in combination function in the activation of the UPR and ER-phagy to maintain ER homeostasis under ER stress in C. albicans.
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Affiliation(s)
- Jiawen Du
- Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - He Zhao
- Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Mengsen Zhu
- Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Yixuan Dong
- Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Liping Peng
- Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Jianrong Li
- Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Qiang Zhao
- Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Qilin Yu
- Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin 300071, China.
| | - Mingchun Li
- Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin 300071, China.
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14
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Pontisso I, Ornelas-Guevara R, Combettes L, Dupont G. A journey in UPR modelling. Biol Cell 2023; 115:e2200111. [PMID: 36751133 DOI: 10.1111/boc.202200111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Revised: 01/11/2023] [Accepted: 01/18/2023] [Indexed: 02/09/2023]
Abstract
Protein folding and protein maturation largely occur in the controlled environment of the Endoplasmic Reticulum (ER). Perturbation to the correct functioning of this organelle leads to altered proteostasis and accumulation of misfolded proteins in the ER lumen. This condition is commonly known as ER stress and is appearing as an important contributor in the pathogenesis of several human diseases. Monitoring of the quality control processes is mediated by the Unfolded Protein Response (UPR). This response consists in a complex network of signalling pathways that aim to restore protein folding and ER homeostasis. Conditions in which UPR is not able to overcome ER stress lead to a switch of the UPR signalling program from an adaptive to a pro-apoptotic one, revealing a key role of UPR in modulating cell fate decisions. Because of its high complexity and its involvement in the regulation of different cellular outcomes, UPR has been the centre of the development of computational models, which tried to better dissect the role of UPR or of its specific components in several contexts. In this review, we go through the existing mathematical models of UPR. We emphasize how their study contributed to an improved characterization of the role of this intricate response in the modulation of cellular functions.
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Affiliation(s)
- Ilaria Pontisso
- Institut de Biologie Intégrative de la Cellule (I2BC) - CNRS, Université Paris-Saclay, Gif-Sur-Yvette, France.,"Calcium signaling and microbial infections", Inserm U1280, Gif-sur-Yvette, France
| | | | - Laurent Combettes
- Institut de Biologie Intégrative de la Cellule (I2BC) - CNRS, Université Paris-Saclay, Gif-Sur-Yvette, France.,"Calcium signaling and microbial infections", Inserm U1280, Gif-sur-Yvette, France
| | - Geneviève Dupont
- Unit of Theoretical Chronobiology, Université Libre de Bruxelles, Brussels, Belgium
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Corona-Sanchez EG, Martínez-García EA, Lujano-Benítez AV, Pizano-Martinez O, Guerra-Durán IA, Chavarria-Avila E, Aguilar-Vazquez A, Martín-Márquez BT, Arellano-Arteaga KJ, Armendariz-Borunda J, Perez-Vazquez F, García-De la Torre I, Llamas-García A, Palacios-Zárate BL, Toriz-González G, Vazquez-Del Mercado M. Autoantibodies in the pathogenesis of idiopathic inflammatory myopathies: Does the endoplasmic reticulum stress response have a role? Front Immunol 2022; 13:940122. [PMID: 36189221 PMCID: PMC9520918 DOI: 10.3389/fimmu.2022.940122] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Accepted: 08/24/2022] [Indexed: 12/20/2022] Open
Abstract
Idiopathic inflammatory myopathies (IIMs) are a group of rare, acquired autoimmune diseases characterized by profound muscle weakness and immune cell invasion into non-necrotic muscle. They are related to the presence of antibodies known as myositis-specific antibodies and myositis-associated antibodies, which are associated with various IIM phenotypes and the clinical prognosis. The possibility of the participation of other pathological mechanisms involved in the inflammatory response in IIM has been proposed. Such mechanisms include the overexpression of major histocompatibility complex class I in myofibers, which correlates with the activation of stress responses of the endoplasmic reticulum (ER). Taking into account the importance of the ER for the maintenance of homeostasis of the musculoskeletal system in the regulation of proteins, there is probably a relationship between immunological and non-immunological processes and autoimmunity, and an example of this might be IIM. We propose that ER stress and its relief mechanisms could be related to inflammatory mechanisms triggering a humoral response in IIM, suggesting that ER stress might be related to the triggering of IIMs and their auto-antibodies’ production.
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Affiliation(s)
- Esther Guadalupe Corona-Sanchez
- Instituto de Investigación en Reumatología y del Sistema Músculo Esqueletico, Departamento de Biología Molecular, Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Guadalajara, Mexico
- Departamento de Fisiología, Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Guadalajara, Mexico
- Universidad de Guadalajara-Cuerpo Académico (UDG-CA)-703, Inmunología y Reumatología, Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Guadalajara, Mexico
| | - Erika Aurora Martínez-García
- Instituto de Investigación en Reumatología y del Sistema Músculo Esqueletico, Departamento de Biología Molecular, Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Guadalajara, Mexico
- Departamento de Fisiología, Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Guadalajara, Mexico
- Universidad de Guadalajara-Cuerpo Académico (UDG-CA)-703, Inmunología y Reumatología, Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Guadalajara, Mexico
| | - Andrea Verónica Lujano-Benítez
- Instituto de Investigación en Reumatología y del Sistema Músculo Esqueletico, Departamento de Biología Molecular, Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Guadalajara, Mexico
- Doctorado en Ciencias Biomedicas, Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Guadalajara, Mexico
| | - Oscar Pizano-Martinez
- Instituto de Investigación en Reumatología y del Sistema Músculo Esqueletico, Departamento de Biología Molecular, Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Guadalajara, Mexico
- Universidad de Guadalajara-Cuerpo Académico (UDG-CA)-703, Inmunología y Reumatología, Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Guadalajara, Mexico
- Departamento de Morfología, Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Guadalajara, Mexico
| | - Ivette Alejandra Guerra-Durán
- Instituto de Investigación en Reumatología y del Sistema Músculo Esqueletico, Departamento de Biología Molecular, Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Guadalajara, Mexico
| | - Efrain Chavarria-Avila
- Instituto de Investigación en Reumatología y del Sistema Músculo Esqueletico, Departamento de Biología Molecular, Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Guadalajara, Mexico
- Departamento de Disciplinas Filosófico Metodológicas e Instrumentales, Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Guadalajara, Mexico
| | - Andrea Aguilar-Vazquez
- Instituto de Investigación en Reumatología y del Sistema Músculo Esqueletico, Departamento de Biología Molecular, Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Guadalajara, Mexico
- Doctorado en Ciencias Biomedicas, Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Guadalajara, Mexico
| | - Beatriz Teresita Martín-Márquez
- Instituto de Investigación en Reumatología y del Sistema Músculo Esqueletico, Departamento de Biología Molecular, Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Guadalajara, Mexico
- Universidad de Guadalajara-Cuerpo Académico (UDG-CA)-703, Inmunología y Reumatología, Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Guadalajara, Mexico
| | - Kevin Javier Arellano-Arteaga
- Hospital Civil de Guadalajara “Dr. Juan I. Menchaca”, Especialidad de Medicina Interna, Padrón Nacional de Posgrados de Calidad (PNPC) Consejo Nacional de Ciencia y Tecnología (CONACyT), Guadalajara, Mexico
| | - Juan Armendariz-Borunda
- Instituto de Biología Molecular en Medicina, Universidad de Guadalajara, Centro Universitario de Ciencias de la Salud, Guadalajara, Mexico
- Escuela de Medicina y Ciencias de la Salud, Tecnológico de Monterrey, Zapopan, Mexico
| | - Felipe Perez-Vazquez
- Departamento de Disciplinas Filosófico Metodológicas e Instrumentales, Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Guadalajara, Mexico
| | - Ignacio García-De la Torre
- Departamento de Inmunología y Reumatología, Hospital General de Occidente y Universidad de Guadalajara, Guadalajara, Mexico
| | - Arcelia Llamas-García
- Hospital Civil de Guadalajara “Dr. Juan I. Menchaca, ” Especialidad de Reumatología, Padrón Nacional de Posgrados de Calidad (PNPC) Consejo Nacional de Ciencia y Tecnología (CONACyT), Guadalajara, Mexico
| | - Brenda Lucía Palacios-Zárate
- Hospital Civil de Guadalajara “Dr. Juan I. Menchaca, ” Especialidad de Reumatología, Padrón Nacional de Posgrados de Calidad (PNPC) Consejo Nacional de Ciencia y Tecnología (CONACyT), Guadalajara, Mexico
| | - Guillermo Toriz-González
- Instituto Transdisciplinar de Investigación y Servicios (ITRANS), Universidad de Guadalajara, Zapopan, Mexico
| | - Monica Vazquez-Del Mercado
- Instituto de Investigación en Reumatología y del Sistema Músculo Esqueletico, Departamento de Biología Molecular, Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Guadalajara, Mexico
- Universidad de Guadalajara-Cuerpo Académico (UDG-CA)-703, Inmunología y Reumatología, Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Guadalajara, Mexico
- Hospital Civil de Guadalajara “Dr. Juan I. Menchaca, ” Especialidad de Reumatología, Padrón Nacional de Posgrados de Calidad (PNPC) Consejo Nacional de Ciencia y Tecnología (CONACyT), Guadalajara, Mexico
- *Correspondence: Monica Vazquez-Del Mercado,
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16
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Ranganathan PR, Narayanan AK, Nawada N, Rao MJ, Reju KS, Priya SC, Gujarathi T, Manjithaya R, Venkata Rao DK. Diacylglycerol kinase alleviates autophagic degradation of the endoplasmic reticulum in SPT10-deficient yeast to enhance triterpene biosynthesis. FEBS Lett 2022; 596:1778-1794. [PMID: 35661158 DOI: 10.1002/1873-3468.14418] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 05/12/2022] [Accepted: 05/18/2022] [Indexed: 11/08/2022]
Abstract
A recent study showed that deletion of the gene encoding the transcription regulator SuPpressor of Ty10 (SPT10) increases total phospholipids, and our previous study established a critical link between phospholipids and the mevalonate/ergosterol (MEV/ERG) pathway, which synthesizes triterpenes. This study aims to use spt10Δ yeast to improve triterpene production. Though MEV/ERG pathway was highly expressed in spt10Δ yeast, results showed insufficient accumulation of key metabolites and also revealed massive endoplasmic reticulum (ER) degradation. We found a stable, massive ER structure when we overexpressed diacylglycerol kinase1 (DGK1OE ) in spt10Δ yeast. Analyses of ER-stress and autophagy suggest that DGK1OE in the spt10Δ strain decreased autophagy, resulting in increased MEV/ERG pathway activity. Heterologous expression of β-amyrin synthase showed significant production of the triterpene β-amyrin in DGK1OE spt10Δ yeast. Overall, our study provides a strategic approach to improve triterpene production by increasing ER biogenesis while limiting ER degradation.
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Affiliation(s)
- Poornima Ramani Ranganathan
- Biochemistry laboratory, CSIR-Central Institute of Medicinal & Aromatic Plants, Research Center, GKVK (post), Allalasandra, India.,Academy of Scientific and Innovative Research (AcSIR), Kamla Nehru Nagar, Sector 19, Ghaziabad, Uttar Pradesh-201 002, India
| | - Ananth Krishna Narayanan
- Biochemistry laboratory, CSIR-Central Institute of Medicinal & Aromatic Plants, Research Center, GKVK (post), Allalasandra, India.,Academy of Scientific and Innovative Research (AcSIR), Kamla Nehru Nagar, Sector 19, Ghaziabad, Uttar Pradesh-201 002, India
| | - Niveditha Nawada
- Biochemistry laboratory, CSIR-Central Institute of Medicinal & Aromatic Plants, Research Center, GKVK (post), Allalasandra, India.,Academy of Scientific and Innovative Research (AcSIR), Kamla Nehru Nagar, Sector 19, Ghaziabad, Uttar Pradesh-201 002, India
| | - Monala Jayaprakash Rao
- Autophagy Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Jakkur, Bangalore-560064, India
| | - Kalyani Sai Reju
- Biochemistry laboratory, CSIR-Central Institute of Medicinal & Aromatic Plants, Research Center, GKVK (post), Allalasandra, India
| | - S Chaithra Priya
- Biochemistry laboratory, CSIR-Central Institute of Medicinal & Aromatic Plants, Research Center, GKVK (post), Allalasandra, India
| | - Tejal Gujarathi
- Autophagy Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Jakkur, Bangalore-560064, India
| | - Ravi Manjithaya
- Autophagy Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Jakkur, Bangalore-560064, India
| | - D K Venkata Rao
- Biochemistry laboratory, CSIR-Central Institute of Medicinal & Aromatic Plants, Research Center, GKVK (post), Allalasandra, India.,Academy of Scientific and Innovative Research (AcSIR), Kamla Nehru Nagar, Sector 19, Ghaziabad, Uttar Pradesh-201 002, India
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Prasad M K, Mohandas S, Ramkumar KM. Role of ER stress inhibitors in the management of diabetes. Eur J Pharmacol 2022; 922:174893. [DOI: 10.1016/j.ejphar.2022.174893] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2022] [Revised: 03/07/2022] [Accepted: 03/09/2022] [Indexed: 12/14/2022]
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18
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Lei Y, Huang Y, Wen X, Yin Z, Zhang Z, Klionsky DJ. How Cells Deal with the Fluctuating Environment: Autophagy Regulation under Stress in Yeast and Mammalian Systems. Antioxidants (Basel) 2022; 11:antiox11020304. [PMID: 35204187 PMCID: PMC8868404 DOI: 10.3390/antiox11020304] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2022] [Revised: 01/28/2022] [Accepted: 01/31/2022] [Indexed: 12/04/2022] Open
Abstract
Eukaryotic cells frequently experience fluctuations of the external and internal environments, such as changes in nutrient, energy and oxygen sources, and protein folding status, which, after reaching a particular threshold, become a type of stress. Cells develop several ways to deal with these various types of stress to maintain homeostasis and survival. Among the cellular survival mechanisms, autophagy is one of the most critical ways to mediate metabolic adaptation and clearance of damaged organelles. Autophagy is maintained at a basal level under normal growing conditions and gets stimulated by stress through different but connected mechanisms. In this review, we summarize the advances in understanding the autophagy regulation mechanisms under multiple types of stress including nutrient, energy, oxidative, and ER stress in both yeast and mammalian systems.
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Affiliation(s)
- Yuchen Lei
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA; (Y.L.); (Y.H.); (X.W.); (Z.Y.); (Z.Z.)
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Yuxiang Huang
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA; (Y.L.); (Y.H.); (X.W.); (Z.Y.); (Z.Z.)
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Xin Wen
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA; (Y.L.); (Y.H.); (X.W.); (Z.Y.); (Z.Z.)
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Zhangyuan Yin
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA; (Y.L.); (Y.H.); (X.W.); (Z.Y.); (Z.Z.)
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Zhihai Zhang
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA; (Y.L.); (Y.H.); (X.W.); (Z.Y.); (Z.Z.)
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Daniel J. Klionsky
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA; (Y.L.); (Y.H.); (X.W.); (Z.Y.); (Z.Z.)
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
- Correspondence:
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19
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Zhou Z, Wang Q, Michalak M. Inositol Requiring Enzyme (IRE), a multiplayer in sensing endoplasmic reticulum stress. Anim Cells Syst (Seoul) 2022; 25:347-357. [PMID: 35059134 PMCID: PMC8765250 DOI: 10.1080/19768354.2021.2020901] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Affiliation(s)
- Zhixin Zhou
- Department of Biochemistry, University of Alberta, Edmonton, Canada
| | - Qian Wang
- Department of Biochemistry, University of Alberta, Edmonton, Canada
| | - Marek Michalak
- Department of Biochemistry, University of Alberta, Edmonton, Canada
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20
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Wang J, Chen M, Wang M, Zhao W, Zhang C, Liu X, Cai M, Qiu Y, Zhang T, Zhou H, Zhao W, Si S, Shao R. The novel ER stress inducer Sec C triggers apoptosis by sulfating ER cysteine residues and degrading YAP via ER stress in pancreatic cancer cells. Acta Pharm Sin B 2022; 12:210-227. [PMID: 35127381 PMCID: PMC8800039 DOI: 10.1016/j.apsb.2021.07.004] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Revised: 06/11/2021] [Accepted: 06/16/2021] [Indexed: 12/14/2022] Open
Abstract
Pancreatic adenocarcinoma (PAAD) is one of the most lethal malignancies. Although gemcitabine (GEM) is a standard treatment for PAAD, resistance limits its application and therapy. Secoemestrin C (Sec C) is a natural compound from the endophytic fungus Emericella, and its anticancer activity has not been investigated since it was isolated. Our research is the first to indicate that Sec C is a broad-spectrum anticancer agent and could exhibit potently similar anticancer activity both in GEM-resistant and GEM-sensitive PAAD cells. Interestingly, Sec C exerted a rapid growth-inhibiting effect (80% death at 6 h), which might be beneficial for patients who need rapid tumor shrinkage before surgery. Liquid chromatography/mass spectrometry and N-acetyl-l-cysteine (NAC) reverse assays show that Sec C sulfates cysteines to disrupt disulfide-bonds formation in endoplasmic reticulum (ER) proteins to cause protein misfolding, leading to ER stress and disorder of lipid biosynthesis. Microarray data and subsequent assays show that ER stress-mediated ER-associated degradation (ERAD) ubiquitinates and downregulates YAP to enhance ER stress via destruction complex (YAP-Axin-GSK-βTrCP), which also elucidates a unique degrading style for YAP. Potent anticancer activity in GEM-resistant cells and low toxicity make Sec C a promising anti-PAAD candidate.
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Affiliation(s)
| | | | - Mengyan Wang
- Key Laboratory of Antibiotic Bioengineering, Ministry of Health, Laboratory of Oncology, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Wenxia Zhao
- Key Laboratory of Antibiotic Bioengineering, Ministry of Health, Laboratory of Oncology, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Conghui Zhang
- Key Laboratory of Antibiotic Bioengineering, Ministry of Health, Laboratory of Oncology, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Xiujun Liu
- Key Laboratory of Antibiotic Bioengineering, Ministry of Health, Laboratory of Oncology, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Meilian Cai
- Key Laboratory of Antibiotic Bioengineering, Ministry of Health, Laboratory of Oncology, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Yuhan Qiu
- Key Laboratory of Antibiotic Bioengineering, Ministry of Health, Laboratory of Oncology, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Tianshu Zhang
- Key Laboratory of Antibiotic Bioengineering, Ministry of Health, Laboratory of Oncology, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Huimin Zhou
- Key Laboratory of Antibiotic Bioengineering, Ministry of Health, Laboratory of Oncology, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Wuli Zhao
- Key Laboratory of Antibiotic Bioengineering, Ministry of Health, Laboratory of Oncology, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Shuyi Si
- Key Laboratory of Antibiotic Bioengineering, Ministry of Health, Laboratory of Oncology, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Rongguang Shao
- Key Laboratory of Antibiotic Bioengineering, Ministry of Health, Laboratory of Oncology, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
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21
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Shi T, Zhou J, Xue A, Lu H, He Y, Yu Y. Characterization and modulation of endoplasmic reticulum stress response target genes in Kluyveromyces marxianus to improve secretory expressions of heterologous proteins. BIOTECHNOLOGY FOR BIOFUELS 2021; 14:236. [PMID: 34906221 PMCID: PMC8670139 DOI: 10.1186/s13068-021-02086-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Accepted: 11/30/2021] [Indexed: 06/09/2023]
Abstract
BACKGROUND Kluyveromyces marxianus is a promising cell factory for producing bioethanol and that raised a demand for a high yield of heterologous proteins in this species. Expressions of heterologous proteins usually lead to the accumulation of misfolded or unfolded proteins in the lumen of the endoplasmic reticulum (ER) and then cause ER stress. To cope with this problem, a group of ER stress response target genes (ESRTs) are induced, mainly through a signaling network called unfolded protein response (UPR). Characterization and modulation of ESRTs direct the optimization of heterologous expressions. However, ESRTs in K. marxianus have not been identified so far. RESULTS In this study, we characterized the ER stress response in K. marxianus for the first time, by using two ER stress-inducing reagents, dithiothreitol (DTT) and tunicamycin (TM). Results showed that the Kar2-Ire1-Hac1 pathway of UPR is well conserved in K. marxianus. About 15% and 6% of genes were upregulated during treatment of DTT and TM, respectively. A total of 115 upregulated genes were characterized as ESRTs, among which 97 genes were identified as UPR target genes and 37 UPR target genes contained UPR elements in their promoters. Genes related to carbohydrate metabolic process and actin filament organization were identified as new types of UPR target genes. A total of 102 ESRTs were overexpressed separately in plasmids and their effects on productions of two different lignocellulolytic enzymes were systematically evaluated. Overexpressing genes involved in carbohydrate metabolism, including PDC1, PGK and VID28, overexpressing a chaperone gene CAJ1 or overexpressing a reductase gene MET13 substantially improved secretion expressions of heterologous proteins. Meanwhile, overexpressing a novel gene, KLMA_50479 (named ESR1), as well as overexpressing genes involved in ER-associated protein degradation (ERAD), including HRD3, USA1 andYET3, reduced the secretory expressions. ESR1 and the aforementioned ERAD genes were deleted from the genome. Resultant mutants, except the yet3Δ mutant, substantially improved secretions of three different heterologous proteins. During the fed-batch fermentation, extracellular activities of an endoxylanase and a glucanase in hrd3Δ cells improved by 43% and 28%, respectively, compared to those in wild-type cells. CONCLUSIONS Our results unveil the transcriptional scope of the ER stress response in K. marxianus and suggest efficient ways to improve productions of heterologous proteins by manipulating expressions of ESRTs.
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Affiliation(s)
- Tianfang Shi
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan University, Shanghai, 200438 China
- Shanghai Engineering Research Center of Industrial Microorganisms, Shanghai, 200438 China
| | - Jungang Zhou
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan University, Shanghai, 200438 China
- Shanghai Engineering Research Center of Industrial Microorganisms, Shanghai, 200438 China
| | - Aijuan Xue
- Institutes of Biomedical Sciences, Fudan University, Shanghai, 200438 China
| | - Hong Lu
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan University, Shanghai, 200438 China
- Shanghai Engineering Research Center of Industrial Microorganisms, Shanghai, 200438 China
| | - Yungang He
- Institutes of Biomedical Sciences, Fudan University, Shanghai, 200438 China
| | - Yao Yu
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan University, Shanghai, 200438 China
- Shanghai Engineering Research Center of Industrial Microorganisms, Shanghai, 200438 China
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22
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Lacroix E, Pereira L, Yoo B, Coyle KM, Chandhok S, Zapf R, Marijan D, Morin RD, Vlachos S, Harden N, Audas TE. Evolutionary conservation of systemic and reversible amyloid aggregation. J Cell Sci 2021; 134:273507. [PMID: 34704593 DOI: 10.1242/jcs.258907] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Accepted: 10/19/2021] [Indexed: 12/30/2022] Open
Abstract
In response to environmental stress, human cells have been shown to form reversible amyloid aggregates within the nucleus, termed amyloid bodies (A-bodies). These protective physiological structures share many of the biophysical characteristics associated with the pathological amyloids found in Alzheimer's and Parkinson's disease. Here, we show that A-bodies are evolutionarily conserved across the eukaryotic domain, with their detection in Drosophila melanogaster and Saccharomyces cerevisiae marking the first examples of these functional amyloids being induced outside of a cultured cell setting. The conditions triggering amyloidogenesis varied significantly among the species tested, with results indicating that A-body formation is a severe, but sublethal, stress response pathway that is tailored to the environmental norms of an organism. RNA-sequencing analyses demonstrate that the regulatory low-complexity long non-coding RNAs that drive A-body aggregation are both conserved and essential in human, mouse and chicken cells. Thus, the identification of these natural and reversible functional amyloids in a variety of evolutionarily diverse species highlights the physiological significance of this protein conformation, and will be informative in advancing our understanding of both functional and pathological amyloid aggregation events. This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Emma Lacroix
- Department of Molecular Biology and Biochemistry, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada.,Center for Cell Biology, Development, and Disease, Burnaby, BC V5A 1S6, Canada
| | - Lionel Pereira
- Department of Molecular Biology and Biochemistry, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada.,Center for Cell Biology, Development, and Disease, Burnaby, BC V5A 1S6, Canada
| | - Byoungjoo Yoo
- Department of Molecular Biology and Biochemistry, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada
| | - Krysta M Coyle
- Department of Molecular Biology and Biochemistry, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada
| | - Sahil Chandhok
- Department of Molecular Biology and Biochemistry, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada.,Center for Cell Biology, Development, and Disease, Burnaby, BC V5A 1S6, Canada
| | - Richard Zapf
- Department of Molecular Biology and Biochemistry, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada.,Center for Cell Biology, Development, and Disease, Burnaby, BC V5A 1S6, Canada
| | - Dane Marijan
- Department of Molecular Biology and Biochemistry, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada.,Center for Cell Biology, Development, and Disease, Burnaby, BC V5A 1S6, Canada
| | - Ryan D Morin
- Department of Molecular Biology and Biochemistry, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada
| | - Stephanie Vlachos
- Department of Molecular Biology and Biochemistry, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada
| | - Nicholas Harden
- Department of Molecular Biology and Biochemistry, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada.,Center for Cell Biology, Development, and Disease, Burnaby, BC V5A 1S6, Canada
| | - Timothy E Audas
- Department of Molecular Biology and Biochemistry, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada.,Center for Cell Biology, Development, and Disease, Burnaby, BC V5A 1S6, Canada
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23
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Han M, Wang W, Gong X, Zhou J, Xu C, Li Y. Increased expression of recombinant chitosanase by co-expression of Hac1p in the yeast Pichia pastoris. Protein Pept Lett 2021; 28:1434-1441. [PMID: 34749599 DOI: 10.2174/0929866528666211105111155] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Revised: 09/13/2021] [Accepted: 09/20/2021] [Indexed: 11/22/2022]
Abstract
BACKGROUND Pichia pastoris is one of the most popular eukaryotic hosts for producing heterologous proteins, while increasing secretion of target proteins is still a top priority for their application in industrial fields. Recently, the research effort to enhance protein production therein has focused on up-regulating the unfolded protein response (UPR). OBJECTIVE We evaluated the effects of activated UPR via Hac1p co-expression with the promoter AOX1 (PAOX1) or GAP (PGAP) on expression of recombinant chitosanase (rCBS) in P. pastoris. METHOD The DNA sequence encoding the chitosanase was chemically synthesized and cloned into pPICZαA and the resulted pPICZαA/rCBS was transformed into P. pastoris for expressing rCBS. The P. pastoris HAC1i cDNA was chemically synthesized and cloned into pPIC3.5K to give pPIC3.5K/Hac1p. The HAC1i cDNA was cloned into pGAPZB and then inserted with HIS4 gene from pAO815 to construct the vector pGAPZB/Hac1p/HIS4. For co-expression of Hac1p, the two plasmids pPIC3.5K/Hac1p and pGAPZB/Hac1p/HIS4 were transformed into P. pastoris harboring the CBS gene. The rCBS was assessed based on chitosanase activity and analyzed by SDS-PAGE. The enhanced Kar2p was detected with western blotting to evaluate UPR. RESULTS Hac1p co-expression with PAOX1 enhanced rCBS secretion by 41% at 28°C. Although the level of UPR resulted from Hac1p co-expression with PAOX1 was equivalent to that with PGAP in terms of the quantity of Kar2p (a hallmark of the UPR), substitution of PGAP for PAOX1 further increased rCBS production by 21%. The methanol-utilizing phenotype of P. pastoris did not affect rCBS secretion with co-expression of Hac1p or not. Finally, Hac1p co-expression with PAOX1 or PGAP promoted rCBS secretion from 22 to 30°C and raised the optimum induction temperature. CONCLUSION The study indicated that Hac1p co-expression with PAOX1 or PGAP is an effective strategy to trigger UPR of P. pastoris and a feasible means for improving production of rCBS therein.
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Affiliation(s)
- Minghai Han
- College of Food and Pharmaceutical Engineering, Guizhou Institute of Technology, Guiyang. China
| | - Weixian Wang
- College of Food and Pharmaceutical Engineering, Guizhou Institute of Technology, Guiyang. China
| | - Xun Gong
- College of Food and Pharmaceutical Engineering, Guizhou Institute of Technology, Guiyang. China
| | - Jianli Zhou
- College of Food and Pharmaceutical Engineering, Guizhou Institute of Technology, Guiyang. China
| | - Cunbin Xu
- College of Food and Pharmaceutical Engineering, Guizhou Institute of Technology, Guiyang. China
| | - Yinfeng Li
- College of Food and Pharmaceutical Engineering, Guizhou Institute of Technology, Guiyang. China
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24
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Shen L, Gao J, Wang Y, Li X, Liu H, Zhong Y. Engineering the endoplasmic reticulum secretory pathway in Trichoderma reesei for improved cellulase production. Enzyme Microb Technol 2021; 152:109923. [PMID: 34688089 DOI: 10.1016/j.enzmictec.2021.109923] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Revised: 09/18/2021] [Accepted: 09/29/2021] [Indexed: 10/20/2022]
Abstract
The filamentous fungus Trichoderma reesei is an extraordinarily efficient cell factory of industrial cellulase for production of biofuels and other bio-based products because of its excellent potential to secrete cellulolytic enzymes. Engineering the protein secretory pathway may be a powerful means for efficient protein production. However, it is uncertain whether this engineering approach could improve cellulase production in T. reesei. Herein, the endoplasmic reticulum (ER) secretory pathway was engineered for the production of cellulolytic enzymes by multiple strategies, including: (I) overexpression of the key components of protein folding (Pdi1, Ero1 and BiP); (II) overexpression of the glycosylation-related elements (Gpt1 and Gls2); (III) knockout of the ER mannosidase I (Mns1) encoding gene mns1. By utilizing these ER engineering strategies, the secretion of β-glucosidase was remarkably elevated in the engineered strains, ranging from 29.2 % to 112.5 %. Furthermore, it was found that engineering these components also regulated the ER stress resistance. More importantly, the total cellulase production was increased with varying degrees, which reached a maximum of 149.4 %, using the filter paper assay (FPA) as a characterization method. These results demonstrated that engineering the ER secretory pathway can enhance protein secretion, particularly for cellulase production, which shed light for the development of high-efficient cellulolytic enzymes for economically feasible bioethanol production from lignocellulosic biomass.
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Affiliation(s)
- Linjing Shen
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao 266237, PR China
| | - Jia Gao
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao 266237, PR China
| | - Yifan Wang
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao 266237, PR China
| | - Xihai Li
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao 266237, PR China
| | - Hong Liu
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao 266237, PR China.
| | - Yaohua Zhong
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao 266237, PR China
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25
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Candida albicans Sfp1 Is Involved in the Cell Wall and Endoplasmic Reticulum Stress Responses Induced by Human Antimicrobial Peptide LL-37. Int J Mol Sci 2021; 22:ijms221910633. [PMID: 34638975 PMCID: PMC8508991 DOI: 10.3390/ijms221910633] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 09/26/2021] [Accepted: 09/28/2021] [Indexed: 12/21/2022] Open
Abstract
Candida albicans is a commensal fungus of humans but can cause infections, particularly in immunocompromised individuals, ranging from superficial to life-threatening systemic infections. The cell wall is the outermost layer of C. albicans that interacts with the host environment. Moreover, antimicrobial peptides (AMPs) are important components in innate immunity and play crucial roles in host defense. Our previous studies showed that the human AMP LL-37 binds to the cell wall of C. albicans, alters the cell wall integrity (CWI) and affects cell adhesion of this pathogen. In this study, we aimed to further investigate the molecular mechanisms underlying the C. albicans response to LL-37. We found that LL-37 causes cell wall stress, activates unfolded protein response (UPR) signaling related to the endoplasmic reticulum (ER), induces ER-derived reactive oxygen species and affects protein secretion. Interestingly, the deletion of the SFP1 gene encoding a transcription factor reduced C. albicans susceptibility to LL-37, which is cell wall-associated. Moreover, in the presence of LL-37, deletion of SFP1 attenuated the UPR pathway, upregulated oxidative stress responsive (OSR) genes and affected bovine serum albumin (BSA) degradation by secreted proteases. Therefore, these findings suggested that Sfp1 positively regulates cell wall integrity and ER homeostasis upon treatment with LL-37 and shed light on pathogen-host interactions.
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26
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Ricci D, Gidalevitz T, Argon Y. The special unfolded protein response in plasma cells. Immunol Rev 2021; 303:35-51. [PMID: 34368957 DOI: 10.1111/imr.13012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Accepted: 06/08/2021] [Indexed: 12/11/2022]
Abstract
The high rate of antibody production places considerable metabolic and folding stress on plasma cells (PC). Not surprisingly, they rely on the unfolded protein response (UPR), a universal signaling, and transcriptional network that monitors the health of the secretory pathway and mounts cellular responses to stress. Typically, the UPR utilizes three distinct stress sensors in the ER membrane, each regulating a subset of targets to re-establish homeostasis. PC use a specialized UPR scheme-they preemptively trigger the UPR via developmental signals and suppress two of the sensors, PERK and ATF6, relying on IRE1 alone. The specialized PC UPR program is tuned to the specific needs at every stage of development-from early biogenesis of secretory apparatus, to massive immunoglobulin expression later. Furthermore, the UPR in PC integrates with other pathways essential in a highly secretory cell-mTOR pathway that ensures efficient synthesis, autophagosomes that recycle components of the synthetic machinery, and apoptotic signaling that controls cell fate in the face of excessive folding stress. This specialized PC program is not shared with other secretory cells, for reasons yet to be defined. In this review, we give a perspective into how and why PC need such a unique UPR program.
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Affiliation(s)
- Daniela Ricci
- Department of Pathology and Lab Medicine, The Childrens' Hospital of Philadelphia and the University of Pennsylvania, Philadelphia, PA, USA
| | - Tali Gidalevitz
- Department of Biology, Drexel University, Philadelphia, PA, USA
| | - Yair Argon
- Department of Pathology and Lab Medicine, The Childrens' Hospital of Philadelphia and the University of Pennsylvania, Philadelphia, PA, USA
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27
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Sukumaran RK, Christopher M, Kooloth-Valappil P, Sreeja-Raju A, Mathew RM, Sankar M, Puthiyamadam A, Adarsh VP, Aswathi A, Rebinro V, Abraham A, Pandey A. Addressing challenges in production of cellulases for biomass hydrolysis: Targeted interventions into the genetics of cellulase producing fungi. BIORESOURCE TECHNOLOGY 2021; 329:124746. [PMID: 33610429 DOI: 10.1016/j.biortech.2021.124746] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2020] [Revised: 01/12/2021] [Accepted: 01/15/2021] [Indexed: 06/12/2023]
Abstract
Lignocellulosic materials are the favoured feedstock for biorefineries due to their abundant availability and non-completion with food. Biobased technologies for refining these materials are limited mainly by the cost of biomass hydrolyzing enzymes, typically sourced from filamentous fungi. Therefore, considerable efforts have been directed at improving the quantity and quality of secreted lignocellulose degrading enzymes from fungi in order to attain overall economic viability. Process improvements and media engineering probably have reached their thresholds and further production enhancements require modifying the fungal metabolism to improve production and secretion of these enzymes. This review focusses on the types and mechanisms of action of known fungal biomass degrading enzymes, our current understanding of the genetic control exerted on their expression, and possible routes for intervention, especially on modulating catabolite repression, transcriptional regulators, signal transduction, secretion pathways etc., in order to improve enzyme productivity, activity and stability.
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Affiliation(s)
- Rajeev K Sukumaran
- Centre for Biofuels, Microbial Processes and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology, Thiruvananthapuram 695019, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh 201002, India.
| | - Meera Christopher
- Centre for Biofuels, Microbial Processes and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology, Thiruvananthapuram 695019, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh 201002, India
| | - Prajeesh Kooloth-Valappil
- Centre for Biofuels, Microbial Processes and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology, Thiruvananthapuram 695019, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh 201002, India
| | - AthiraRaj Sreeja-Raju
- Centre for Biofuels, Microbial Processes and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology, Thiruvananthapuram 695019, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh 201002, India
| | - Reshma M Mathew
- Centre for Biofuels, Microbial Processes and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology, Thiruvananthapuram 695019, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh 201002, India
| | - Meena Sankar
- Centre for Biofuels, Microbial Processes and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology, Thiruvananthapuram 695019, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh 201002, India
| | - Anoop Puthiyamadam
- Centre for Biofuels, Microbial Processes and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology, Thiruvananthapuram 695019, India
| | - Velayudhanpillai-Prasannakumari Adarsh
- Centre for Biofuels, Microbial Processes and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology, Thiruvananthapuram 695019, India
| | - Aswathi Aswathi
- Centre for Biofuels, Microbial Processes and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology, Thiruvananthapuram 695019, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh 201002, India
| | - Valan Rebinro
- Centre for Biofuels, Microbial Processes and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology, Thiruvananthapuram 695019, India
| | - Amith Abraham
- Department of Chemical Engineering, Hanyang University, Seoul, Republic of Korea
| | - Ashok Pandey
- Centre for Innovation and Translational Research, CSIR-Indian Institute of Toxicology Research, Lucknow, India
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28
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Raschmanová H, Weninger A, Knejzlík Z, Melzoch K, Kovar K. Engineering of the unfolded protein response pathway in Pichia pastoris: enhancing production of secreted recombinant proteins. Appl Microbiol Biotechnol 2021; 105:4397-4414. [PMID: 34037840 PMCID: PMC8195892 DOI: 10.1007/s00253-021-11336-5] [Citation(s) in RCA: 58] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Revised: 04/30/2021] [Accepted: 05/06/2021] [Indexed: 12/14/2022]
Abstract
Folding and processing of proteins in the endoplasmic reticulum (ER) are major impediments in the production and secretion of proteins from Pichia pastoris (Komagataella sp.). Overexpression of recombinant genes can overwhelm the innate secretory machinery of the P. pastoris cell, and incorrectly folded proteins may accumulate inside the ER. To restore proper protein folding, the cell naturally triggers an unfolded protein response (UPR) pathway, which upregulates the expression of genes coding for chaperones and other folding-assisting proteins (e.g., Kar2p, Pdi1, Ero1p) via the transcription activator Hac1p. Unfolded/misfolded proteins that cannot be repaired are degraded via the ER-associated degradation (ERAD) pathway, which decreases productivity. Co-expression of selected UPR genes, along with the recombinant gene of interest, is a common approach to enhance the production of properly folded, secreted proteins. Such an approach, however, is not always successful and sometimes, protein productivity decreases because of an unbalanced UPR. This review summarizes successful chaperone co-expression strategies in P. pastoris that are specifically related to overproduction of foreign proteins and the UPR. In addition, it illustrates possible negative effects on the cell's physiology and productivity resulting from genetic engineering of the UPR pathway. We have focused on Pichia's potential for commercial production of valuable proteins and we aim to optimize molecular designs so that production strains can be tailored to suit a specific heterologous product. KEY POINTS: • Chaperones co-expressed with recombinant genes affect productivity in P. pastoris. • Enhanced UPR may impair strain physiology and promote protein degradation. • Gene copy number of the target gene and the chaperone determine the secretion rate.
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Affiliation(s)
- Hana Raschmanová
- Department of Biotechnology, University of Chemistry and Technology Prague, Prague, Czech Republic.
- Institute of Chemistry and Biotechnology, Zurich University of Applied Sciences ZHAW, Wädenswil, Switzerland.
| | - Astrid Weninger
- Institute of Molecular Biotechnology, Graz University of Technology, Graz, Austria
| | - Zdeněk Knejzlík
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Prague, Czech Republic
| | - Karel Melzoch
- Department of Biotechnology, University of Chemistry and Technology Prague, Prague, Czech Republic
| | - Karin Kovar
- Institute of Chemistry and Biotechnology, Zurich University of Applied Sciences ZHAW, Wädenswil, Switzerland
- daspool Association, Wädenswil, Switzerland
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29
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Bi Y, Chang Y, Liu Q, Mao Y, Zhai K, Zhou Y, Jiao R, Ji G. ERp44/CG9911 promotes fat storage in Drosophila adipocytes by regulating ER Ca 2+ homeostasis. Aging (Albany NY) 2021; 13:15013-15031. [PMID: 34031268 PMCID: PMC8221293 DOI: 10.18632/aging.203063] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Accepted: 03/27/2021] [Indexed: 12/12/2022]
Abstract
Fat storage is one of the important strategies employed in regulating energy homeostasis. Impaired lipid storage causes metabolic disorders in both mammals and Drosophila. In this study, we report CG9911, the Drosophila homolog of ERp44 (endoplasmic reticulum protein 44) plays a role in regulating adipose tissue fat storage. Using the CRISPR/Cas9 system, we generated a CG9911 mutant line deleting 5 bp of the coding sequence. The mutant flies exhibit phenotypes of lower bodyweight, fewer lipid droplets, reduced TAG level and increased expression of lipolysis related genes. The increased lipolysis phenotype is enhanced in the presence of ER stresses and suppressed by a reduction of the ER Ca2+. Moreover, loss of CG9911 per se results in a decrease of ER Ca2+ in the fat body. Together, our results reveal a novel function of CG9911 in promoting fat storage via regulating ER Ca2+ signal in Drosophila.
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Affiliation(s)
- Youkun Bi
- Key Laboratory of Interdisciplinary Research, Chinese Academy of Sciences, Beijing 100101, China.,University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yan Chang
- Key Laboratory of Interdisciplinary Research, Chinese Academy of Sciences, Beijing 100101, China.,University of Chinese Academy of Sciences, Beijing 100049, China
| | - Qun Liu
- Key Laboratory of Interdisciplinary Research, Chinese Academy of Sciences, Beijing 100101, China.,University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yang Mao
- Key Laboratory of Interdisciplinary Research, Chinese Academy of Sciences, Beijing 100101, China.,University of Chinese Academy of Sciences, Beijing 100049, China
| | - Kui Zhai
- Key Laboratory of Interdisciplinary Research, Chinese Academy of Sciences, Beijing 100101, China.,University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yuanli Zhou
- Key Laboratory of Protein and Peptide Pharmaceutical, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Renjie Jiao
- Key Laboratory of Interdisciplinary Research, Chinese Academy of Sciences, Beijing 100101, China.,Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, Guangzhou 510182, China
| | - Guangju Ji
- Key Laboratory of Interdisciplinary Research, Chinese Academy of Sciences, Beijing 100101, China
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30
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Le QG, Kimata Y. Multiple Ways for Stress Sensing and Regulation of the Endoplasmic Reticulum-stress Sensors. Cell Struct Funct 2021; 46:37-49. [PMID: 33775971 PMCID: PMC10511038 DOI: 10.1247/csf.21015] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2021] [Accepted: 03/11/2021] [Indexed: 11/11/2022] Open
Abstract
Dysfunction of the endoplasmic reticulum (ER), so-called ER stress, is accompanied with accumulation of unfolded proteins in the ER. Eukaryotic cells commonly have an ER-located transmembrane protein, Ire1, which triggers cellular protective events against ER stress. In animal cells, PERK and ATF6 also initiate the ER-stress response. As a common strategy to control the activity of these ER-stress sensors, an ER-resident molecular chaperone, BiP, serves as their negative regulator, and dissociates from them in response to ER stress. Although it sounds reasonable that unfolded proteins and Ire1 compete for BiP association, some publications argue against this competition model. Moreover, yeast Ire1 (and possibly also the mammalian major Ire1 paralogue IRE1α) directly detects ER-accumulated unfolded proteins, and subsequently oligomerizes for its further activation. Apart from protein misfolding, the saturation of membrane phospholipids is another outcome of ER-stressing stimuli, which is sensed by the transmembrane domain of Ire1. This review describes the canonical and up-to-date insights concerning stress-sensing and regulatory mechanisms of yeast Ire1 and metazoan ER-stress sensors.Key words: endoplasmic reticulum, stress, unfolded protein response, molecular chaperone.
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Affiliation(s)
- Quynh Giang Le
- Institute of Biomedicine and Pharmacy, Vietnam Military Medical University, 222 Phung Hung, Ha Dong, Ha Noi, Vietnam
- Institute of Biotechnology, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet road, Cau Giay, Ha Noi, Vietnam
| | - Yukio Kimata
- Graduate School of Science and Technology, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara, 630-0192, Japan
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Starke J, Harting R, Maurus I, Leonard M, Bremenkamp R, Heimel K, Kronstad JW, Braus GH. Unfolded Protein Response and Scaffold Independent Pheromone MAP Kinase Signaling Control Verticillium dahliae Growth, Development, and Plant Pathogenesis. J Fungi (Basel) 2021; 7:jof7040305. [PMID: 33921172 PMCID: PMC8071499 DOI: 10.3390/jof7040305] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 04/12/2021] [Accepted: 04/12/2021] [Indexed: 12/13/2022] Open
Abstract
Differentiation, growth, and virulence of the vascular plant pathogen Verticillium dahliae depend on a network of interconnected cellular signaling cascades. The transcription factor Hac1 of the endoplasmic reticulum-associated unfolded protein response (UPR) is required for initial root colonization, fungal growth, and vascular propagation by conidiation. Hac1 is essential for the formation of microsclerotia as long-time survival resting structures in the field. Single endoplasmic reticulum-associated enzymes for linoleic acid production as precursors for oxylipin signal molecules support fungal growth but not pathogenicity. Microsclerotia development, growth, and virulence further require the pheromone response mitogen-activated protein kinase (MAPK) pathway, but without the Ham5 scaffold function. The MAPK phosphatase Rok1 limits resting structure development of V.dahliae, but promotes growth, conidiation, and virulence. The interplay between UPR and MAPK signaling cascades includes several potential targets for fungal growth control for supporting disease management of the vascular pathogen V.dahliae.
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Affiliation(s)
- Jessica Starke
- Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics and Göttingen Center for Molecular Biosciences (GZMB), University of Göttingen, 37077 Göttingen, Germany; (J.S.); (R.H.); (I.M.); (M.L.); (R.B.); (K.H.)
| | - Rebekka Harting
- Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics and Göttingen Center for Molecular Biosciences (GZMB), University of Göttingen, 37077 Göttingen, Germany; (J.S.); (R.H.); (I.M.); (M.L.); (R.B.); (K.H.)
| | - Isabel Maurus
- Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics and Göttingen Center for Molecular Biosciences (GZMB), University of Göttingen, 37077 Göttingen, Germany; (J.S.); (R.H.); (I.M.); (M.L.); (R.B.); (K.H.)
| | - Miriam Leonard
- Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics and Göttingen Center for Molecular Biosciences (GZMB), University of Göttingen, 37077 Göttingen, Germany; (J.S.); (R.H.); (I.M.); (M.L.); (R.B.); (K.H.)
| | - Rica Bremenkamp
- Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics and Göttingen Center for Molecular Biosciences (GZMB), University of Göttingen, 37077 Göttingen, Germany; (J.S.); (R.H.); (I.M.); (M.L.); (R.B.); (K.H.)
| | - Kai Heimel
- Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics and Göttingen Center for Molecular Biosciences (GZMB), University of Göttingen, 37077 Göttingen, Germany; (J.S.); (R.H.); (I.M.); (M.L.); (R.B.); (K.H.)
| | - James W. Kronstad
- Michael Smith Laboratories, Department of Microbiology and Immunology, University of British Columbia, Vancouver, BC V6T 1Z4, Canada;
| | - Gerhard H. Braus
- Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics and Göttingen Center for Molecular Biosciences (GZMB), University of Göttingen, 37077 Göttingen, Germany; (J.S.); (R.H.); (I.M.); (M.L.); (R.B.); (K.H.)
- Correspondence: ; Tel.: +49-(0)551-39-33771
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Does Saccharomyces cerevisiae Require Specific Post-Translational Silencing against Leaky Translation of Hac1up? Microorganisms 2021; 9:microorganisms9030620. [PMID: 33802931 PMCID: PMC8002603 DOI: 10.3390/microorganisms9030620] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Revised: 03/13/2021] [Accepted: 03/16/2021] [Indexed: 11/24/2022] Open
Abstract
HAC1 encodes a key transcription factor that transmits the unfolded protein response (UPR) from the endoplasmic reticulum (ER) to the nucleus and regulates downstream UPR genes in Saccharomyces cerevisiae. In response to the accumulation of unfolded proteins in the ER, Ire1p oligomers splice HAC1 pre-mRNA (HAC1u) via a non-conventional process and allow the spliced HAC1 (HAC1i) to be translated efficiently. However, leaky splicing and translation of HAC1u may occur in non-UPR cells to induce undesirable UPR. To control accidental UPR activation, multiple fail-safe mechanisms have been proposed to prevent leaky HAC1 splicing and translation and to facilitate rapid degradation of translated Hac1up and Hac1ip. Among proposed regulatory mechanisms is a degron sequence encoded at the 5′ end of the HAC1 intron that silences Hac1up expression. To investigate the necessity of an intron-encoded degron sequence that specifically targets Hac1up for degradation, we employed publicly available transcriptomic data to quantify leaky HAC1 splicing and translation in UPR-induced and non-UPR cells. As expected, we found that HAC1u is only efficiently spliced into HAC1i and efficiently translated into Hac1ip in UPR-induced cells. However, our analysis of ribosome profiling data confirmed frequent occurrence of leaky translation of HAC1u regardless of UPR induction, demonstrating the inability of translation fail-safe to completely inhibit Hac1up production. Additionally, among 32 yeast HAC1 surveyed, the degron sequence is highly conserved by Saccharomyces yeast but is poorly conserved by all other yeast species. Nevertheless, the degron sequence is the most conserved HAC1 intron segment in yeasts. These results suggest that the degron sequence may indeed play an important role in mitigating the accumulation of Hac1up to prevent accidental UPR activation in the Saccharomyces yeast.
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Polčic P, Machala Z. Effects of Non-Thermal Plasma on Yeast Saccharomyces cerevisiae. Int J Mol Sci 2021; 22:ijms22052247. [PMID: 33668158 PMCID: PMC7956799 DOI: 10.3390/ijms22052247] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Revised: 02/16/2021] [Accepted: 02/20/2021] [Indexed: 12/26/2022] Open
Abstract
Cold plasmas generated by various electrical discharges can affect cell physiology or induce cell damage that may often result in the loss of viability. Many cold plasma-based technologies have emerged in recent years that are aimed at manipulating the cells within various environments or tissues. These include inactivation of microorganisms for the purpose of sterilization, food processing, induction of seeds germination, but also the treatment of cells in the therapy. Mechanisms that underlie the plasma-cell interactions are, however, still poorly understood. Dissection of cellular pathways or structures affected by plasma using simple eukaryotic models is therefore desirable. Yeast Saccharomyces cerevisiae is a traditional model organism with unprecedented impact on our knowledge of processes in eukaryotic cells. As such, it had been also employed in studies of plasma-cell interactions. This review focuses on the effects of cold plasma on yeast cells.
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Affiliation(s)
- Peter Polčic
- Department of Biochemistry, Faculty of Natural Sciences, Comenius University in Bratislava, Mlynská dolina CH1, Ilkovičova 6, 84215 Bratislava, Slovakia
- Correspondence: ; Tel.: +421-2-60296-398
| | - Zdenko Machala
- Division of Environmental Physics, Faculty of Mathematics, Physics, and Informatics, Comenius University in Bratislava, Mlynská dolina F2, 84248 Bratislava, Slovakia;
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Le QG, Ishiwata-Kimata Y, Phuong TH, Fukunaka S, Kohno K, Kimata Y. The ADP-binding kinase region of Ire1 directly contributes to its responsiveness to endoplasmic reticulum stress. Sci Rep 2021; 11:4506. [PMID: 33627709 PMCID: PMC7904763 DOI: 10.1038/s41598-021-83890-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Accepted: 02/05/2021] [Indexed: 01/22/2023] Open
Abstract
Upon endoplasmic-reticulum (ER) stress, the ER-located transmembrane protein, Ire1, is autophosphorylated and acts as an endoribonuclease to trigger the unfolded protein response (UPR). Previous biochemical studies have shown that Ire1 exhibits strong endoribonuclease activity when its cytosolic kinase region captures ADP. Here, we asked how this event contributes to the regulation of Ire1 activity. At the beginning of this study, we obtained a luminal-domain mutant of Saccharomyces cerevisiae Ire1, deltaIdeltaIIIdeltaV/Y225H Ire1, which is deduced to be controlled by none of the luminal-side regulatory events. ER-stress responsiveness of deltaIdeltaIIIdeltaV/Y225H Ire1 was largely compromised by a further mutation on the kinase region, D797N/K799N, which allows Ire1 to be activated without capturing ADP. Therefore, in addition to the ER-luminal domain of Ire1, which monitors ER conditions, the kinase region is directly involved in the ER-stress responsiveness of Ire1. We propose that potent ER stress harms cells’ “vividness”, increasing the cytosolic ADP/ATP ratio, and eventually strongly activates Ire1. This mechanism seems to contribute to the suppression of inappropriately potent UPR under weak ER-stress conditions.
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Affiliation(s)
- Quynh Giang Le
- Division of Bioscience, Graduate School of Science and Technology, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara, 630-0192, Japan.,Institute of Biotechnology, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet road, Cau Giay, Ha Noi, Vietnam
| | - Yuki Ishiwata-Kimata
- Division of Bioscience, Graduate School of Science and Technology, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara, 630-0192, Japan
| | - Thi Huong Phuong
- Division of Bioscience, Graduate School of Science and Technology, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara, 630-0192, Japan
| | - Shigeto Fukunaka
- Division of Bioscience, Graduate School of Science and Technology, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara, 630-0192, Japan
| | - Kenji Kohno
- Graduate School of Life Science, University of Hyogo, 3-2-1 Kouto, Kamigori-cho, Ako-gun, Hyogo, 678-1297, Japan
| | - Yukio Kimata
- Division of Bioscience, Graduate School of Science and Technology, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara, 630-0192, Japan.
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Eesmaa A, Yu LY, Göös H, Nõges K, Kovaleva V, Hellman M, Zimmermann R, Jung M, Permi P, Varjosalo M, Lindholm P, Saarma M. The cytoprotective protein MANF promotes neuronal survival independently from its role as a GRP78 cofactor. J Biol Chem 2021; 296:100295. [PMID: 33460650 PMCID: PMC7949057 DOI: 10.1016/j.jbc.2021.100295] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 01/07/2021] [Accepted: 01/12/2021] [Indexed: 12/14/2022] Open
Abstract
Mesencephalic astrocyte-derived neurotrophic factor (MANF) is an endoplasmic reticulum (ER)-stress-regulated protein exhibiting cytoprotective properties through a poorly understood mechanism in various in vitro and in vivo models of neuronal and non-neuronal damage. Although initially characterized as a secreted neurotrophic factor for midbrain dopamine neurons, MANF has recently gained more interest for its intracellular role in regulating the ER homeostasis, including serving as a cofactor of the chaperone glucose-regulated protein 78 (GRP78). We aimed for a better understanding of the neuroprotective mechanisms of MANF. Here we show for the first time that MANF promotes the survival of ER-stressed neurons in vitro as a general unfolded protein response (UPR) regulator, affecting several UPR pathways simultaneously. Interestingly, MANF does not affect naïve neurons. We hypothesize that MANF regulates UPR signaling toward a mode more compatible with neuronal survival. Screening of MANF interacting proteins from two mammalian cell lines revealed a conserved interactome of 15 proteins including several ER chaperones such as GRP78, GRP170, protein disulfide isomerase family A member 1, and protein disulfide isomerase family A member 6. Further characterization confirmed previously published finding that MANF is a cofactor of GRP78 interacting with its nucleotide binding domain. Using microscale thermophoresis and nuclear magnetic resonance spectroscopy, we discovered that MANF is an ATP binding protein and that ATP blocks the MANF-GRP78 interaction. Interestingly, functional analysis of the antiapoptotic properties of MANF mutants in cultured neurons revealed divergent roles of MANF as a GRP78 cofactor and as an antiapoptotic regulator of UPR. We conclude that the co-factor type interaction with GRP78 is dispensable for the survival-promoting activity of MANF in neurons.
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Affiliation(s)
- Ave Eesmaa
- Institute of Biotechnology, HiLIFE, University of Helsinki, Helsinki, Finland
| | - Li-Ying Yu
- Institute of Biotechnology, HiLIFE, University of Helsinki, Helsinki, Finland
| | - Helka Göös
- Institute of Biotechnology, HiLIFE, University of Helsinki, Helsinki, Finland
| | - Kristofer Nõges
- Institute of Biotechnology, HiLIFE, University of Helsinki, Helsinki, Finland
| | - Vera Kovaleva
- Institute of Biotechnology, HiLIFE, University of Helsinki, Helsinki, Finland
| | - Maarit Hellman
- Department of Chemistry, Nanoscience Center, University of Jyväskylä, Jyväskylä, Finland
| | - Richard Zimmermann
- Medical Biochemistry and Molecular Biology, Saarland University, Homburg, Germany
| | - Martin Jung
- Medical Biochemistry and Molecular Biology, Saarland University, Homburg, Germany
| | - Perttu Permi
- Department of Chemistry, Nanoscience Center, University of Jyväskylä, Jyväskylä, Finland; Department of Biological and Environmental Science, Nanoscience Center, University of Jyväskylä, Jyväskylä, Finland
| | - Markku Varjosalo
- Institute of Biotechnology, HiLIFE, University of Helsinki, Helsinki, Finland
| | - Päivi Lindholm
- Institute of Biotechnology, HiLIFE, University of Helsinki, Helsinki, Finland.
| | - Mart Saarma
- Institute of Biotechnology, HiLIFE, University of Helsinki, Helsinki, Finland.
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36
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Li X, Sun S, Appathurai S, Sundaram A, Plumb R, Mariappan M. A Molecular Mechanism for Turning Off IRE1α Signaling during Endoplasmic Reticulum Stress. Cell Rep 2020; 33:108563. [PMID: 33378667 PMCID: PMC7809255 DOI: 10.1016/j.celrep.2020.108563] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 09/14/2020] [Accepted: 12/06/2020] [Indexed: 12/15/2022] Open
Abstract
Misfolded proteins in the endoplasmic reticulum (ER) activate IRE1α endoribonuclease in mammalian cells, which mediates XBP1 mRNA splicing to produce an active transcription factor. This promotes the expression of specific genes to alleviate ER stress, thereby attenuating IRE1α. Although sustained activation of IRE1α is linked to human diseases, it is not clear how IRE1α is attenuated during ER stress. Here, we identify that Sec63 is a subunit of the previously identified IRE1α/Sec61 translocon complex. We find that Sec63 recruits and activates BiP ATPase through its luminal J-domain to bind onto IRE1α. This leads to inhibition of higher-order oligomerization and attenuation of IRE1α RNase activity during prolonged ER stress. In Sec63-deficient cells, IRE1α remains activated for a long period of time despite the presence of excess BiP in the ER. Thus, our data suggest that the Sec61 translocon bridges IRE1α with Sec63/BiP to regulate the dynamics of IRE1α signaling in cells. The stress sensor IRE1α is attenuated during prolonged ER stress by a poorly understood mechanism. Li et al. show that IRE1α forms a complex with the Sec61/Sec63 translocon in cells. Sec63 mediates BiP binding to IRE1α and thereby inhibits IRE1α oligomerization and attenuates IRE1α signaling during prolonged ER stress.
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Affiliation(s)
- Xia Li
- Department of Cell Biology, Nanobiology Institute, Yale School of Medicine, Yale West Campus, West Haven, CT 06516, USA
| | - Sha Sun
- Department of Cell Biology, Nanobiology Institute, Yale School of Medicine, Yale West Campus, West Haven, CT 06516, USA
| | - Suhila Appathurai
- Department of Cell Biology, Nanobiology Institute, Yale School of Medicine, Yale West Campus, West Haven, CT 06516, USA
| | - Arunkumar Sundaram
- Department of Cell Biology, Nanobiology Institute, Yale School of Medicine, Yale West Campus, West Haven, CT 06516, USA
| | - Rachel Plumb
- Department of Cell Biology, Nanobiology Institute, Yale School of Medicine, Yale West Campus, West Haven, CT 06516, USA
| | - Malaiyalam Mariappan
- Department of Cell Biology, Nanobiology Institute, Yale School of Medicine, Yale West Campus, West Haven, CT 06516, USA.
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Aghaei M, Dastghaib S, Aftabi S, Aghanoori MR, Alizadeh J, Mokarram P, Mehrbod P, Ashrafizadeh M, Zarrabi A, McAlinden KD, Eapen MS, Sohal SS, Sharma P, Zeki AA, Ghavami S. The ER Stress/UPR Axis in Chronic Obstructive Pulmonary Disease and Idiopathic Pulmonary Fibrosis. Life (Basel) 2020; 11:1. [PMID: 33374938 PMCID: PMC7821926 DOI: 10.3390/life11010001] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Revised: 12/14/2020] [Accepted: 12/18/2020] [Indexed: 12/18/2022] Open
Abstract
Cellular protein homeostasis in the lungs is constantly disrupted by recurrent exposure to various external and internal stressors, which may cause considerable protein secretion pressure on the endoplasmic reticulum (ER), resulting in the survival and differentiation of these cell types to meet the increased functional demands. Cells are able to induce a highly conserved adaptive mechanism, known as the unfolded protein response (UPR), to manage such stresses. UPR dysregulation and ER stress are involved in numerous human illnesses, such as metabolic syndrome, fibrotic diseases, and neurodegeneration, and cancer. Therefore, effective and specific compounds targeting the UPR pathway are being considered as potential therapies. This review focuses on the impact of both external and internal stressors on the ER in idiopathic pulmonary fibrosis (IPF) and chronic obstructive pulmonary disease (COPD) and discusses the role of the UPR signaling pathway activation in the control of cellular damage and specifically highlights the potential involvement of non-coding RNAs in COPD. Summaries of pathogenic mechanisms associated with the ER stress/UPR axis contributing to IPF and COPD, and promising pharmacological intervention strategies, are also presented.
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Affiliation(s)
- Mahmoud Aghaei
- Department of Human Anatomy and Cell Science, Rady Faculty of Health Sciences, Max Rady College of Medicine, University of Manitoba, Winnipeg, MB R3E 0J9, Canada; (M.A.); (S.A.); (J.A.)
- Department of Clinical Biochemistry, School of Pharmacy and Pharmaceutical Sciences, Isfahan University of Medical Sciences, Isfahan 8174673461, Iran
| | - Sanaz Dastghaib
- Department of Clinical Biochemistry, School of Medicine, Shiraz University of Medical Sciences, Shiraz 7134845794, Iran; (S.D.); (P.M.)
- Autophagy Research Center, Shiraz University of Medical Sciences, Shiraz 7134845794, Iran
| | - Sajjad Aftabi
- Department of Human Anatomy and Cell Science, Rady Faculty of Health Sciences, Max Rady College of Medicine, University of Manitoba, Winnipeg, MB R3E 0J9, Canada; (M.A.); (S.A.); (J.A.)
- Medical Physics Department, Cancer Care Manitoba, University of Manitoba, Winnipeg, MB R3E 0V9, Canada
| | - Mohamad-Reza Aghanoori
- Division of Neurodegenerative Disorders, St Boniface Hospital Albrechtsen Research Centre, University of Manitoba, Winnipeg, MB R2H 2A6, Canada;
- Department of Internal Medicine, University of Manitoba, Winnipeg, MB R3E 0V9, Canada
| | - Javad Alizadeh
- Department of Human Anatomy and Cell Science, Rady Faculty of Health Sciences, Max Rady College of Medicine, University of Manitoba, Winnipeg, MB R3E 0J9, Canada; (M.A.); (S.A.); (J.A.)
- Research Institute of Oncology and Hematology, Cancer Care Manitoba, University of Manitoba, Winnipeg, MB R3E 0V9, Canada
- Biology of Breathing Theme, Children Hospital Research Institute of Manitoba, University of Manitoba, Winnipeg, MB R3E 0V9, Canada
| | - Pooneh Mokarram
- Department of Clinical Biochemistry, School of Medicine, Shiraz University of Medical Sciences, Shiraz 7134845794, Iran; (S.D.); (P.M.)
- Autophagy Research Center, Shiraz University of Medical Sciences, Shiraz 7134845794, Iran
| | - Parvaneh Mehrbod
- Influenza and Respiratory Viruses Department, Pasteur Institute of Iran, Tehran 1316943551, Iran;
| | - Milad Ashrafizadeh
- Faculty of Engineering and Natural Sciences, Sabanci University, Orta Mahalle, Üniversite Caddesi No. 27, Orhanlı, Tuzla, 34956 Istanbul, Turkey;
- Sabanci University Nanotechnology Research and Application Center (SUNUM), Tuzla, 34956 Istanbul, Turkey;
| | - Ali Zarrabi
- Sabanci University Nanotechnology Research and Application Center (SUNUM), Tuzla, 34956 Istanbul, Turkey;
| | - Kielan Darcy McAlinden
- Respiratory Translational Research Group, Department of Laboratory Medicine, School of Health Sciences, University of Tasmania, Launceston 7250, Tasmania, Australia; (K.D.M.); (M.S.E.); (S.S.S.)
| | - Mathew Suji Eapen
- Respiratory Translational Research Group, Department of Laboratory Medicine, School of Health Sciences, University of Tasmania, Launceston 7250, Tasmania, Australia; (K.D.M.); (M.S.E.); (S.S.S.)
| | - Sukhwinder Singh Sohal
- Respiratory Translational Research Group, Department of Laboratory Medicine, School of Health Sciences, University of Tasmania, Launceston 7250, Tasmania, Australia; (K.D.M.); (M.S.E.); (S.S.S.)
| | - Pawan Sharma
- Center for Translational Medicine, Jane & Leonard Korman Respiratory Institute, Thomas Jefferson University, Philadelphia, PA 19107, USA;
| | - Amir A. Zeki
- Davis School of Medicine, Department of Internal Medicine, Division of Pulmonary, Critical Care, and Sleep Medicine, UC Davis Lung Center, University of California, Davis, CA 95616, USA;
- Veterans Affairs Medical Center, Mather, CA 95655, USA
| | - Saeid Ghavami
- Department of Human Anatomy and Cell Science, Rady Faculty of Health Sciences, Max Rady College of Medicine, University of Manitoba, Winnipeg, MB R3E 0J9, Canada; (M.A.); (S.A.); (J.A.)
- Autophagy Research Center, Shiraz University of Medical Sciences, Shiraz 7134845794, Iran
- Research Institute of Oncology and Hematology, Cancer Care Manitoba, University of Manitoba, Winnipeg, MB R3E 0V9, Canada
- Biology of Breathing Theme, Children Hospital Research Institute of Manitoba, University of Manitoba, Winnipeg, MB R3E 0V9, Canada
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Abstract
Bioethanol is the largest biotechnology product and the most dominant biofuel globally. Saccharomyces cerevisiae is the most favored microorganism employed for its industrial production. However, obtaining maximum yields from an ethanol fermentation remains a technical challenge, since cellular stresses detrimentally impact on the efficiency of yeast cell growth and metabolism. Ethanol fermentation stresses potentially include osmotic, chaotropic, oxidative, and heat stress, as well as shifts in pH. Well-developed stress responses and tolerance mechanisms make S. cerevisiae industrious, with bioprocessing techniques also being deployed at industrial scale for the optimization of fermentation parameters and the effective management of inhibition issues. Overlap exists between yeast responses to different forms of stress. This review outlines yeast fermentation stresses and known mechanisms conferring stress tolerance, with their further elucidation and improvement possessing the potential to improve fermentation efficiency.
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39
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Dhakal S, Macreadie I. Protein Homeostasis Networks and the Use of Yeast to Guide Interventions in Alzheimer's Disease. Int J Mol Sci 2020; 21:E8014. [PMID: 33126501 PMCID: PMC7662794 DOI: 10.3390/ijms21218014] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 10/24/2020] [Accepted: 10/26/2020] [Indexed: 12/12/2022] Open
Abstract
Alzheimer's Disease (AD) is a progressive multifactorial age-related neurodegenerative disorder that causes the majority of deaths due to dementia in the elderly. Although various risk factors have been found to be associated with AD progression, the cause of the disease is still unresolved. The loss of proteostasis is one of the major causes of AD: it is evident by aggregation of misfolded proteins, lipid homeostasis disruption, accumulation of autophagic vesicles, and oxidative damage during the disease progression. Different models have been developed to study AD, one of which is a yeast model. Yeasts are simple unicellular eukaryotic cells that have provided great insights into human cell biology. Various yeast models, including unmodified and genetically modified yeasts, have been established for studying AD and have provided significant amount of information on AD pathology and potential interventions. The conservation of various human biological processes, including signal transduction, energy metabolism, protein homeostasis, stress responses, oxidative phosphorylation, vesicle trafficking, apoptosis, endocytosis, and ageing, renders yeast a fascinating, powerful model for AD. In addition, the easy manipulation of the yeast genome and availability of methods to evaluate yeast cells rapidly in high throughput technological platforms strengthen the rationale of using yeast as a model. This review focuses on the description of the proteostasis network in yeast and its comparison with the human proteostasis network. It further elaborates on the AD-associated proteostasis failure and applications of the yeast proteostasis network to understand AD pathology and its potential to guide interventions against AD.
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Affiliation(s)
| | - Ian Macreadie
- School of Science, RMIT University, Bundoora, Victoria 3083, Australia;
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40
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Urra H, Pihán P, Hetz C. The UPRosome - decoding novel biological outputs of IRE1α function. J Cell Sci 2020; 133:133/15/jcs218107. [PMID: 32788208 DOI: 10.1242/jcs.218107] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Different perturbations alter the function of the endoplasmic reticulum (ER), resulting in the accumulation of misfolded proteins in its lumen, a condition termed ER stress. To restore ER proteostasis, a highly conserved pathway is engaged, known as the unfolded protein response (UPR), triggering adaptive programs or apoptosis of terminally damaged cells. IRE1α (also known as ERN1), the most conserved UPR sensor, mediates the activation of responses to determine cell fate under ER stress. The complexity of IRE1α regulation and its signaling outputs is mediated in part by the assembly of a dynamic multi-protein complex, named the UPRosome, that regulates IRE1α activity and the crosstalk with other pathways. We discuss several studies identifying components of the UPRosome that have illuminated novel functions in cell death, autophagy, DNA damage, energy metabolism and cytoskeleton dynamics. Here, we provide a theoretical analysis to assess the biological significance of the UPRosome and present the results of a systematic bioinformatics analysis of the available IRE1α interactome data sets followed by functional enrichment clustering. This in silico approach decoded that IRE1α also interacts with proteins involved in the cell cycle, transport, differentiation, response to viral infection and immune response. Thus, defining the spectrum of IRE1α-binding partners will reveal novel signaling outputs and the relevance of the pathway to human diseases.
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Affiliation(s)
- Hery Urra
- Biomedical Neuroscience Institute (BNI), Faculty of Medicine, University of Chile, Santiago 8380453, Chile .,Center for Geroscience, Brain Health and Metabolism (GERO), Santiago 7800003, Chile.,Program of Cellular and Molecular Biology, Institute of Biomedical Sciences (ICBM), University of Chile, Santiago 8380453, Chile
| | - Philippe Pihán
- Biomedical Neuroscience Institute (BNI), Faculty of Medicine, University of Chile, Santiago 8380453, Chile.,Center for Geroscience, Brain Health and Metabolism (GERO), Santiago 7800003, Chile.,Program of Cellular and Molecular Biology, Institute of Biomedical Sciences (ICBM), University of Chile, Santiago 8380453, Chile
| | - Claudio Hetz
- Biomedical Neuroscience Institute (BNI), Faculty of Medicine, University of Chile, Santiago 8380453, Chile .,Center for Geroscience, Brain Health and Metabolism (GERO), Santiago 7800003, Chile.,Program of Cellular and Molecular Biology, Institute of Biomedical Sciences (ICBM), University of Chile, Santiago 8380453, Chile.,The Buck Institute for Research in Aging, Novato, CA 94945, USA
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van Ziel AM, Scheper W. The UPR in Neurodegenerative Disease: Not Just an Inside Job. Biomolecules 2020; 10:biom10081090. [PMID: 32707908 PMCID: PMC7465596 DOI: 10.3390/biom10081090] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Revised: 07/16/2020] [Accepted: 07/20/2020] [Indexed: 12/26/2022] Open
Abstract
Neurons are highly specialized cells that continuously and extensively communicate with other neurons, as well as glia cells. During their long lifetime, the post-mitotic neurons encounter many stressful situations that can disrupt protein homeostasis (proteostasis). The importance of tight protein quality control is illustrated by neurodegenerative disorders where disturbed neuronal proteostasis causes neuronal dysfunction and loss. For their unique function, neurons require regulated and long-distance transport of membrane-bound cargo and organelles. This highlights the importance of protein quality control in the neuronal endomembrane system, to which the unfolded protein response (UPR) is instrumental. The UPR is a highly conserved stress response that is present in all eukaryotes. However, recent studies demonstrate the existence of cell-type-specific aspects of the UPR, as well as cell non-autonomous UPR signaling. Here we discuss these novel insights in view of the complex cellular architecture of the brain and the implications for neurodegenerative diseases.
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Affiliation(s)
- Anna Maria van Ziel
- Department of Clinical Genetics, Amsterdam University Medical Centers location VUmc, 1081 HV Amsterdam, The Netherlands;
- Department of Functional Genomics, Center for Neurogenomics and Cognitive Research, Vrije Universiteit (VU), 1081 HV Amsterdam, The Netherlands
| | - Wiep Scheper
- Department of Clinical Genetics, Amsterdam University Medical Centers location VUmc, 1081 HV Amsterdam, The Netherlands;
- Department of Functional Genomics, Center for Neurogenomics and Cognitive Research, Vrije Universiteit (VU), 1081 HV Amsterdam, The Netherlands
- Correspondence: ; Tel.: +31-20-5982771
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42
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Zhao H, Wang Y, Li B, Zheng T, Liu X, Hu BH, Che J, Zhao T, Chen J, Hatzoglou M, Zhang X, Fan Z, Zheng Q. Role of Endoplasmic Reticulum Stress in Otitis Media. Front Genet 2020; 11:495. [PMID: 32536938 PMCID: PMC7267009 DOI: 10.3389/fgene.2020.00495] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2019] [Accepted: 04/20/2020] [Indexed: 11/19/2022] Open
Abstract
Endoplasmic reticulum (ER) stress occurs in many inflammatory responses. Here, we investigated the role of ER stress and its associated apoptosis in otitis media (OM) to elucidate the mechanisms of OM and the signaling crosstalk between ER stress and other cell damage pathways, including inflammatory cytokines and apoptosis. We examined the expression of inflammatory cytokine- and ER stress-related genes by qRT-PCR, Western blotting, and immunohistochemistry (IHC) in the middle ear of C57BL/6J mice after challenge with peptidoglycan polysaccharide (PGPS), an agent inducing OM. We also evaluated the effect of the suppression of ER stress with tauroursodeoxycholic acid (TUDCA), an ER stress inhibitor. The study revealed the upregulation of ER stress- and apoptosis-related gene expression after the PGPS treatment, specifically ATF6, CHOP, BIP, caspase-12, and caspase-3. TUDCA treatment of PGPS-treated mice decreased OM; reduced the expression of CHOP, BIP, and caspase 3; and significantly decreased the proinflammatory gene expression of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6). These results suggest that PGPS triggers ER stress and downstream proinflammatory gene expression in OM and that inhibition of ER stress alleviates OM. We propose that ER stress plays a critical role in inflammation and cell death, leading to the development of OM and points to ER stress inhibition as a potential therapeutic approach for the prevention of OM.
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Affiliation(s)
- Hongchun Zhao
- Department of Otolaryngology-Head and Neck Surgery, Shandong Provincial ENT Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China.,Department of Otolaryngology/Head and Neck Surgery, Institute of Otolaryngology, Affiliated Hospital of Binzhou Medical University, Binzhou, China
| | - Yanfei Wang
- Department of Otolaryngology/Head and Neck Surgery, Institute of Otolaryngology, Affiliated Hospital of Binzhou Medical University, Binzhou, China
| | - Bo Li
- Hearing and Speech Rehabilitation Institute, College of Special Education, Binzhou Medical University, Yantai, China
| | - Tihua Zheng
- Hearing and Speech Rehabilitation Institute, College of Special Education, Binzhou Medical University, Yantai, China
| | - Xiuzhen Liu
- Clinical Laboratory, Affiliated Hospital of Binzhou Medical University, Binzhou, China
| | - Bo Hua Hu
- Center for Hearing and Deafness, University at Buffalo, Buffalo, NY, United States
| | - Juan Che
- Department of Otolaryngology/Head and Neck Surgery, Institute of Otolaryngology, Affiliated Hospital of Binzhou Medical University, Binzhou, China
| | - Tong Zhao
- Hearing and Speech Rehabilitation Institute, College of Special Education, Binzhou Medical University, Yantai, China
| | - Jun Chen
- Department of Otolaryngology/Head and Neck Surgery, Institute of Otolaryngology, Affiliated Hospital of Binzhou Medical University, Binzhou, China
| | - Maria Hatzoglou
- Department of Genetics, Case Western Reserve University, Cleveland, OH, United States
| | - Xiaolin Zhang
- Department of Otolaryngology/Head and Neck Surgery, Institute of Otolaryngology, Affiliated Hospital of Binzhou Medical University, Binzhou, China
| | - Zhaomin Fan
- Department of Otolaryngology-Head and Neck Surgery, Shandong Provincial ENT Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Qingyin Zheng
- Department of Otolaryngology-Head & Neck Surgery, Case Western Reserve University, Cleveland, OH, United States
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43
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Oikonomou C, Hendershot LM. Disposing of misfolded ER proteins: A troubled substrate's way out of the ER. Mol Cell Endocrinol 2020; 500:110630. [PMID: 31669350 PMCID: PMC6911830 DOI: 10.1016/j.mce.2019.110630] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/15/2019] [Revised: 09/19/2019] [Accepted: 10/20/2019] [Indexed: 12/12/2022]
Abstract
Secreted, plasma membrane, and resident proteins of the secretory pathway are synthesized in the endoplasmic reticulum (ER) where they undergo post-translational modifications, oxidative folding, and subunit assembly in tightly monitored processes. An ER quality control (ERQC) system oversees protein maturation and ensures that only those reaching their native state will continue trafficking into the secretory pathway to reach their final destinations. Those that fail must be recognized and eliminated to maintain ER homeostasis. Two cellular mechanisms have been identified to rid the ER of terminally unfolded, misfolded, and aggregated proteins. ER-associated degradation (ERAD) was discovered nearly 30 years ago and entails the identification of improperly matured secretory pathway proteins and their retrotranslocation to the cytosol for degradation by the ubiquitin-proteasome system. ER-phagy has been more recently described and caters to larger, more complex proteins and protein aggregates that are not readily handled by ERAD. This pathway has unique upstream components and relies on the same downstream effectors of autophagy used in other cellular processes to deliver clients to lysosomes for degradation. In this review, we describe the main elements of ERQC, ERAD, and ER-phagy and focus on recent advances in these fields.
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Affiliation(s)
- Christina Oikonomou
- St. Jude Children's Research Hospital, Memphis, TN, 38104, USA; The University of Tennessee Health Science Center, Memphis, TN, USA
| | - Linda M Hendershot
- St. Jude Children's Research Hospital, Memphis, TN, 38104, USA; The University of Tennessee Health Science Center, Memphis, TN, USA.
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44
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Sahu RK, Saha N, Das L, Sahu PK, Sariki SK, Tomar RS. SWI/SNF chromatin remodelling complex contributes to clearance of cytoplasmic protein aggregates and regulates unfolded protein response in Saccharomyces cerevisiae. FEBS J 2020; 287:3024-3041. [PMID: 31846549 DOI: 10.1111/febs.15180] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2019] [Revised: 10/09/2019] [Accepted: 12/13/2019] [Indexed: 12/20/2022]
Abstract
Chromatin remodelling complexes are multi-subunit assemblies, each containing a catalytic ATPase and translocase that is capable of mobilizing nucleosomes to alter the chromatin structure. SWI/SNF remodelling complexes with higher DNA translocation efficiency evict histones or slide the nucleosomes away from each other making DNA accessible for transcription and repair machinery. Chromatin remodelling at the promoter of stress-responsive genes by SWI/SNF becomes necessary during the heat and proteotoxic stress. While the involvement of SWI/SNF in transcription of stress-responsive genes has been studied extensively, the regulation of proteostasis by SWI/SNF is not well understood. This study demonstrates critical functions of SWI/SNF in response to cadmium-induced proteotoxic stress. Deletion of either ATPase-translocase subunit of SWI/SNF complex (Swi2/Snf2) or a regulatory subunit Swi3 abrogates the clearance of cadmium-induced protein aggregates. Our results suggest that Snf2 and Swi3 regulate the protein folding in endoplasmic reticulum (ER) that reduces the chances of forming unfolded protein aggregates under the proteotoxic stress of cadmium. The Ire1-mediated unfolded protein response (UPR) maintains ER homeostasis by upregulating the expression of chaperones and ER-associated degradation (ERAD) components. We found that Snf2 maintains normal oxidative environment essential for Ire1 activity. Deletion of SNF2 reduced the Ire1 activity and UPR, indicating involvement of Snf2 in Ire1-mediated ER proteostasis. Together, these findings suggest that SWI/SNF complex regulates ER homeostasis and protein folding crucial for tolerating proteotoxic stress.
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Affiliation(s)
- Rakesh Kumar Sahu
- Laboratory of Chromatin Biology, Department of Biological Sciences, Indian Institute of Science Education and Research, Bhopal, India
| | - Nitu Saha
- Laboratory of Chromatin Biology, Department of Biological Sciences, Indian Institute of Science Education and Research, Bhopal, India
| | - Laxmidhar Das
- Laboratory of Chromatin Biology, Department of Biological Sciences, Indian Institute of Science Education and Research, Bhopal, India
| | - Pushpendra Kumar Sahu
- Laboratory of Chromatin Biology, Department of Biological Sciences, Indian Institute of Science Education and Research, Bhopal, India
| | - Santhosh Kumar Sariki
- Laboratory of Chromatin Biology, Department of Biological Sciences, Indian Institute of Science Education and Research, Bhopal, India
| | - Raghuvir Singh Tomar
- Laboratory of Chromatin Biology, Department of Biological Sciences, Indian Institute of Science Education and Research, Bhopal, India
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45
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Amin-Wetzel N, Neidhardt L, Yan Y, Mayer MP, Ron D. Unstructured regions in IRE1α specify BiP-mediated destabilisation of the luminal domain dimer and repression of the UPR. eLife 2019; 8:50793. [PMID: 31873072 PMCID: PMC6996924 DOI: 10.7554/elife.50793] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Accepted: 12/23/2019] [Indexed: 12/15/2022] Open
Abstract
Coupling of endoplasmic reticulum (ER) stress to dimerisation-dependent activation of the UPR transducer IRE1 is incompletely understood. Whilst the luminal co-chaperone ERdj4 promotes a complex between the Hsp70 BiP and IRE1's stress-sensing luminal domain (IRE1LD) that favours the latter's monomeric inactive state and loss of ERdj4 de-represses IRE1, evidence linking these cellular and in vitro observations is presently lacking. We report that enforced loading of endogenous BiP onto endogenous IRE1α repressed UPR signalling in CHO cells and deletions in the IRE1α locus that de-repressed the UPR in cells, encode flexible regions of IRE1LD that mediated BiP-induced monomerisation in vitro. Changes in the hydrogen exchange mass spectrometry profile of IRE1LD induced by ERdj4 and BiP confirmed monomerisation and were consistent with active destabilisation of the IRE1LD dimer. Together, these observations support a competition model whereby waning ER stress passively partitions ERdj4 and BiP to IRE1LD to initiate active repression of UPR signalling.
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Affiliation(s)
- Niko Amin-Wetzel
- Cambridge Institute for Medical Research (CIMR), University of Cambridge, Cambridge, United Kingdom
| | - Lisa Neidhardt
- Cambridge Institute for Medical Research (CIMR), University of Cambridge, Cambridge, United Kingdom
| | - Yahui Yan
- Cambridge Institute for Medical Research (CIMR), University of Cambridge, Cambridge, United Kingdom
| | - Matthias P Mayer
- Center for Molecular Biology of Heidelberg University (ZMBH), DKFZ-ZMBH Alliance, Heidelberg, Germany
| | - David Ron
- Cambridge Institute for Medical Research (CIMR), University of Cambridge, Cambridge, United Kingdom
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46
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Functional Diversification of ER Stress Responses in Arabidopsis. Trends Biochem Sci 2019; 45:123-136. [PMID: 31753702 DOI: 10.1016/j.tibs.2019.10.008] [Citation(s) in RCA: 72] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Revised: 10/04/2019] [Accepted: 10/22/2019] [Indexed: 12/12/2022]
Abstract
The endoplasmic reticulum (ER) is responsible for the synthesis of one-third of the cellular proteome and is constantly challenged by physiological and environmental situations that can perturb its homeostasis and lead to the accumulation of misfolded secretory proteins, a condition referred to as ER stress. In response, the ER evokes a set of intracellular signaling processes, collectively known as the unfolded protein response (UPR), which are designed to restore biosynthetic capacity of the ER. As single-cell organisms evolved into multicellular life, the UPR complexity has increased to suit their growth and development. In this review, we discuss recent advances in the understanding of the UPR, emphasizing conserved UPR elements between plants and metazoans and highlighting unique plant-specific features.
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47
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Gao P, Chai Y, Song J, Liu T, Chen P, Zhou L, Ge X, Guo X, Han J, Yang H. Reprogramming the unfolded protein response for replication by porcine reproductive and respiratory syndrome virus. PLoS Pathog 2019; 15:e1008169. [PMID: 31738790 PMCID: PMC6932825 DOI: 10.1371/journal.ppat.1008169] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Revised: 12/26/2019] [Accepted: 10/29/2019] [Indexed: 12/16/2022] Open
Abstract
The unfolded protein response (UPR) in the endoplasmic reticulum (ER) constitutes a critical component of host innate immunity against microbial infections. In this report, we show that porcine reproductive and respiratory syndrome virus (PRRSV) utilizes the UPR machinery for its own benefit. We provide evidence that the virus targets the UPR central regulator GRP78 for proteasomal degradation via a mechanism that requires viral glycoprotein GP2a, while both IRE1-XBP1s and PERK-eIF2α-ATF4 signaling branches of the UPR are turned on at early stage of infection. The activated effector XBP1s was found to enter the nucleus, but ATF4 was unexpectedly diverted to cytoplasmic viral replication complexes by means of nonstructural proteins nsp2/3 to promote viral RNA synthesis. RNAi knockdown of either ATF4 or XBP1s dramatically attenuated virus titers, while overexpression caused increases. These observations reveal attractive host targets (e.g., ATF4 and XBP1s) for antiviral drugs and have implications in vaccine development. Porcine reproductive and respiratory syndrome virus (PRRSV) poses a major threat to the worldwide swine industry, but no effective vaccines or antiviral drugs are available. A better understanding of the pathogen-host interactions that support PRRSV replication is essential for understanding viral pathogenesis and the development of preventive measures. Here we report that PRRSV utilizes unconventional strategies to reprogram the unfolded protein response (UPR) of the host to its own advantage. The virus targets GRP78 for partial degradation to create a favorable environment for UPR induction and hijacks ATF4 into cytoplasmic replication complexes to promote viral RNA synthesis. The data also reveal potential targets (e.g., ATF4 and XBP1s) for antiviral drugs and have implications in vaccine development.
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Affiliation(s)
- Peng Gao
- Key Laboratory of Animal Epidemiology of the Ministry of Agriculture and Rural Affairs, China Agricultural University College of Veterinary Medicine, Beijing, People’s Republic of China
| | - Yue Chai
- Key Laboratory of Animal Epidemiology of the Ministry of Agriculture and Rural Affairs, China Agricultural University College of Veterinary Medicine, Beijing, People’s Republic of China
| | - Jiangwei Song
- Key Laboratory of Animal Epidemiology of the Ministry of Agriculture and Rural Affairs, China Agricultural University College of Veterinary Medicine, Beijing, People’s Republic of China
| | - Teng Liu
- Key Laboratory of Animal Epidemiology of the Ministry of Agriculture and Rural Affairs, China Agricultural University College of Veterinary Medicine, Beijing, People’s Republic of China
| | - Peng Chen
- Key Laboratory of Animal Epidemiology of the Ministry of Agriculture and Rural Affairs, China Agricultural University College of Veterinary Medicine, Beijing, People’s Republic of China
| | - Lei Zhou
- Key Laboratory of Animal Epidemiology of the Ministry of Agriculture and Rural Affairs, China Agricultural University College of Veterinary Medicine, Beijing, People’s Republic of China
| | - Xinna Ge
- Key Laboratory of Animal Epidemiology of the Ministry of Agriculture and Rural Affairs, China Agricultural University College of Veterinary Medicine, Beijing, People’s Republic of China
| | - Xin Guo
- Key Laboratory of Animal Epidemiology of the Ministry of Agriculture and Rural Affairs, China Agricultural University College of Veterinary Medicine, Beijing, People’s Republic of China
| | - Jun Han
- Key Laboratory of Animal Epidemiology of the Ministry of Agriculture and Rural Affairs, China Agricultural University College of Veterinary Medicine, Beijing, People’s Republic of China
- * E-mail:
| | - Hanchun Yang
- Key Laboratory of Animal Epidemiology of the Ministry of Agriculture and Rural Affairs, China Agricultural University College of Veterinary Medicine, Beijing, People’s Republic of China
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48
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Karagöz GE, Aragón T, Acosta-Alvear D. Recent advances in signal integration mechanisms in the unfolded protein response. F1000Res 2019; 8. [PMID: 31723416 PMCID: PMC6833987 DOI: 10.12688/f1000research.19848.1] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 10/22/2019] [Indexed: 12/15/2022] Open
Abstract
Since its discovery more than 25 years ago, great progress has been made in our understanding of the unfolded protein response (UPR), a homeostatic mechanism that adjusts endoplasmic reticulum (ER) function to satisfy the physiological demands of the cell. However, if ER homeostasis is unattainable, the UPR switches to drive cell death to remove defective cells in an effort to protect the health of the organism. This functional dichotomy places the UPR at the crossroads of the adaptation versus apoptosis decision. Here, we focus on new developments in UPR signaling mechanisms, in the interconnectivity among the signaling pathways that make up the UPR in higher eukaryotes, and in the coordination between the UPR and other fundamental cellular processes.
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Affiliation(s)
- G Elif Karagöz
- Max Perutz Labs Vienna, Medical University of Vienna, Vienna, Austria
| | - Tomás Aragón
- Department of Gene Therapy and Regulation of Gene Expression, University of Navarra, Pamplona, Spain
| | - Diego Acosta-Alvear
- Department of Molecular, Cellular, and Developmental Biology, University of California, Santa Barbara, Santa Barbara, Santa Barbara, CA, USA
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49
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GRP78 activates the Wnt/HOXB9 pathway to promote invasion and metastasis of hepatocellular carcinoma by chaperoning LRP6. Exp Cell Res 2019; 383:111493. [DOI: 10.1016/j.yexcr.2019.07.006] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Revised: 06/28/2019] [Accepted: 07/07/2019] [Indexed: 11/20/2022]
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50
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Stroberg W, Eilertsen J, Schnell S. Information processing by endoplasmic reticulum stress sensors. J R Soc Interface 2019; 16:20190288. [PMID: 31506041 DOI: 10.1098/rsif.2019.0288] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The unfolded protein response (UPR) is a collection of cellular feedback mechanisms that seek to maintain protein folding homeostasis in the endoplasmic reticulum (ER). When the ER is 'stressed', through either high protein folding demand or undersupply of chaperones and foldases, stress sensing proteins in the ER membrane initiate the UPR. Recently, experiments have indicated that these signalling molecules detect stress by being both sequestered by free chaperones and activated by free unfolded proteins. However, it remains unclear what advantage this bidirectional sensor control offers stressed cells. Here, we show that combining positive regulation of sensor activity by unfolded proteins with negative regulation by chaperones allows the sensor to make a more informative measurement of ER stress. The increase in the information capacity of the combined sensing mechanism stems from stretching of the active range of the sensor, at the cost of increased uncertainty due to the integration of multiple signals. These results provide a possible rationale for the evolution of the observed stress-sensing mechanism.
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Affiliation(s)
- Wylie Stroberg
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Justin Eilertsen
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Santiago Schnell
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI, USA.,Department of Computational Medicine and Bioinformatics, University of Michigan Medical School, Ann Arbor, MI, USA
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