1
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Hill J, Nyathi Y. USP5 enhances SGTA mediated protein quality control. PLoS One 2022; 17:e0257786. [PMID: 35895711 PMCID: PMC9328565 DOI: 10.1371/journal.pone.0257786] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Accepted: 07/11/2022] [Indexed: 11/18/2022] Open
Abstract
Mislocalised membrane proteins (MLPs) present a risk to the cell due to exposed hydrophobic amino acids which cause MLPs to aggregate. Previous studies identified SGTA as a key component of the machinery that regulates the quality control of MLPs. Overexpression of SGTA promotes deubiqutination of MLPs resulting in their accumulation in cytosolic inclusions, suggesting SGTA acts in collaboration with deubiquitinating enzymes (DUBs) to exert these effects. However, the DUBs that play a role in this process have not been identified. In this study we have identified the ubiquitin specific peptidase 5 (USP5) as a DUB important in regulating the quality control of MLPs. We show that USP5 is in complex with SGTA, and this association is increased in the presence of an MLP. Overexpression of SGTA results in an increase in steady-state levels of MLPs suggesting a delay in proteasomal degradation of substrates. However, our results show that this effect is strongly dependent on the presence of USP5. We find that in the absence of USP5, the ability of SGTA to increase the steady state levels of MLPs is compromised. Moreover, knockdown of USP5 results in a reduction in the steady state levels of MLPs, while overexpression of USP5 increases the steady state levels. Our findings suggest that the interaction of SGTA with USP5 enables specific MLPs to escape proteasomal degradation allowing selective modulation of MLP quality control. These findings progress our understanding of aggregate formation, a hallmark in a range of neurodegenerative diseases and type II diabetes, as well as physiological processes of aggregate clearance.
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Affiliation(s)
- Jake Hill
- School of Life Sciences, Joseph Banks Laboratories, University of Lincoln, Lincoln, United Kingdom
- School of Chemistry and Bioscience, Faculty of Life Sciences, University of Bradford, Bradford, United Kingdom
| | - Yvonne Nyathi
- School of Life Sciences, Joseph Banks Laboratories, University of Lincoln, Lincoln, United Kingdom
- School of Chemistry and Bioscience, Faculty of Life Sciences, University of Bradford, Bradford, United Kingdom
- * E-mail:
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2
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Lemasson M, Caignard G, Unterfinger Y, Attoui H, Bell-Sakyi L, Hirchaud E, Moutailler S, Johnson N, Vitour D, Richardson J, Lacour SA. Exploration of binary protein-protein interactions between tick-borne flaviviruses and Ixodes ricinus. Parasit Vectors 2021; 14:144. [PMID: 33676573 PMCID: PMC7937244 DOI: 10.1186/s13071-021-04651-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Accepted: 02/18/2021] [Indexed: 12/23/2022] Open
Abstract
Background Louping ill virus (LIV) and tick-borne encephalitis virus (TBEV) are tick-borne flaviviruses that are both transmitted by the major European tick, Ixodes ricinus. Despite the importance of I. ricinus as an arthropod vector, its capacity to acquire and subsequently transmit viruses, known as vector competence, is poorly understood. At the molecular scale, vector competence is governed in part by binary interactions established between viral and cellular proteins within infected tick cells. Methods To investigate virus-vector protein–protein interactions (PPIs), the entire set of open reading frames for LIV and TBEV was screened against an I. ricinus cDNA library established from three embryonic tick cell lines using yeast two-hybrid methodology (Y2H). PPIs revealed for each viral bait were retested in yeast by applying a gap repair (GR) strategy, and notably against the cognate protein of both viruses, to determine whether the PPIs were specific for a single virus or common to both. The interacting tick proteins were identified by automatic BLASTX, and in silico analyses were performed to expose the biological processes targeted by LIV and TBEV. Results For each virus, we identified 24 different PPIs involving six viral proteins and 22 unique tick proteins, with all PPIs being common to both viruses. According to our data, several viral proteins (pM, M, NS2A, NS4A, 2K and NS5) target multiple tick protein modules implicated in critical biological pathways. Of note, the NS5 and pM viral proteins establish PPI with several tumor necrosis factor (TNF) receptor-associated factor (TRAF) proteins, which are essential adaptor proteins at the nexus of multiple signal transduction pathways. Conclusion We provide the first description of the TBEV/LIV-I. ricinus PPI network, and indeed of any PPI network involving a tick-borne virus and its tick vector. While further investigation will be needed to elucidate the role of each tick protein in the replication cycle of tick-borne flaviviruses, our study provides a foundation for understanding the vector competence of I. ricinus at the molecular level. Indeed, certain PPIs may represent molecular determinants of vector competence of I. ricinus for TBEV and LIV, and potentially for other tick-borne flaviviruses.![]() Supplementary Information The online version contains supplementary material available at 10.1186/s13071-021-04651-3.
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Affiliation(s)
- Manon Lemasson
- UMR 1161 Virologie Laboratoire de Santé Animale, ANSES, INRAE, Ecole Nationale Vétérinaire d'Alfort, Paris-Est Sup, Maisons-Alfort, France
| | - Grégory Caignard
- UMR 1161 Virologie Laboratoire de Santé Animale, ANSES, INRAE, Ecole Nationale Vétérinaire d'Alfort, Paris-Est Sup, Maisons-Alfort, France
| | - Yves Unterfinger
- UMR 1161 Virologie Laboratoire de Santé Animale, ANSES, INRAE, Ecole Nationale Vétérinaire d'Alfort, Paris-Est Sup, Maisons-Alfort, France
| | - Houssam Attoui
- UMR 1161 Virologie Laboratoire de Santé Animale, ANSES, INRAE, Ecole Nationale Vétérinaire d'Alfort, Paris-Est Sup, Maisons-Alfort, France
| | - Lesley Bell-Sakyi
- Department of Infection Biology and Microbiomes, Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, UK
| | - Edouard Hirchaud
- Viral Genetic and Biosecurity Unit, Ploufragan-Plouzané-Niort Laboratory, ANSES, Ploufragan, France
| | - Sara Moutailler
- UMR BIPAR, Laboratoire de Santé Animale, ANSES, INRAE, Ecole Nationale Vétérinaire d'Alfort, Paris-Est Sup, Maisons-Alfort, France
| | | | - Damien Vitour
- UMR 1161 Virologie Laboratoire de Santé Animale, ANSES, INRAE, Ecole Nationale Vétérinaire d'Alfort, Paris-Est Sup, Maisons-Alfort, France
| | - Jennifer Richardson
- UMR 1161 Virologie Laboratoire de Santé Animale, ANSES, INRAE, Ecole Nationale Vétérinaire d'Alfort, Paris-Est Sup, Maisons-Alfort, France
| | - Sandrine A Lacour
- UMR 1161 Virologie Laboratoire de Santé Animale, ANSES, INRAE, Ecole Nationale Vétérinaire d'Alfort, Paris-Est Sup, Maisons-Alfort, France.
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3
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Abildgaard AB, Gersing SK, Larsen-Ledet S, Nielsen SV, Stein A, Lindorff-Larsen K, Hartmann-Petersen R. Co-Chaperones in Targeting and Delivery of Misfolded Proteins to the 26S Proteasome. Biomolecules 2020; 10:E1141. [PMID: 32759676 PMCID: PMC7463752 DOI: 10.3390/biom10081141] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Revised: 07/31/2020] [Accepted: 08/02/2020] [Indexed: 12/11/2022] Open
Abstract
Protein homeostasis (proteostasis) is essential for the cell and is maintained by a highly conserved protein quality control (PQC) system, which triages newly synthesized, mislocalized and misfolded proteins. The ubiquitin-proteasome system (UPS), molecular chaperones, and co-chaperones are vital PQC elements that work together to facilitate degradation of misfolded and toxic protein species through the 26S proteasome. However, the underlying mechanisms are complex and remain partly unclear. Here, we provide an overview of the current knowledge on the co-chaperones that directly take part in targeting and delivery of PQC substrates for degradation. While J-domain proteins (JDPs) target substrates for the heat shock protein 70 (HSP70) chaperones, nucleotide-exchange factors (NEFs) deliver HSP70-bound substrates to the proteasome. So far, three NEFs have been established in proteasomal delivery: HSP110 and the ubiquitin-like (UBL) domain proteins BAG-1 and BAG-6, the latter acting as a chaperone itself and carrying its substrates directly to the proteasome. A better understanding of the individual delivery pathways will improve our ability to regulate the triage, and thus regulate the fate of aberrant proteins involved in cell stress and disease, examples of which are given throughout the review.
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Affiliation(s)
- Amanda B. Abildgaard
- Department of Biology, The Linderstrøm-Lang Centre for Protein Science, University of Copenhagen, Ole Maaløes Vej 5, DK-2200 Copenhagen, Denmark; (A.B.A.); (S.K.G.); (S.L.-L.); (K.L.-L.)
| | - Sarah K. Gersing
- Department of Biology, The Linderstrøm-Lang Centre for Protein Science, University of Copenhagen, Ole Maaløes Vej 5, DK-2200 Copenhagen, Denmark; (A.B.A.); (S.K.G.); (S.L.-L.); (K.L.-L.)
| | - Sven Larsen-Ledet
- Department of Biology, The Linderstrøm-Lang Centre for Protein Science, University of Copenhagen, Ole Maaløes Vej 5, DK-2200 Copenhagen, Denmark; (A.B.A.); (S.K.G.); (S.L.-L.); (K.L.-L.)
| | - Sofie V. Nielsen
- Department of Biology, Section for Computational and RNA Biology, University of Copenhagen, Ole Maaløes Vej 5, DK-2200 Copenhagen, Denmark; (S.V.N.); (A.S.)
| | - Amelie Stein
- Department of Biology, Section for Computational and RNA Biology, University of Copenhagen, Ole Maaløes Vej 5, DK-2200 Copenhagen, Denmark; (S.V.N.); (A.S.)
| | - Kresten Lindorff-Larsen
- Department of Biology, The Linderstrøm-Lang Centre for Protein Science, University of Copenhagen, Ole Maaløes Vej 5, DK-2200 Copenhagen, Denmark; (A.B.A.); (S.K.G.); (S.L.-L.); (K.L.-L.)
| | - Rasmus Hartmann-Petersen
- Department of Biology, The Linderstrøm-Lang Centre for Protein Science, University of Copenhagen, Ole Maaløes Vej 5, DK-2200 Copenhagen, Denmark; (A.B.A.); (S.K.G.); (S.L.-L.); (K.L.-L.)
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4
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Graham JB, Canniff NP, Hebert DN. TPR-containing proteins control protein organization and homeostasis for the endoplasmic reticulum. Crit Rev Biochem Mol Biol 2019; 54:103-118. [PMID: 31023093 DOI: 10.1080/10409238.2019.1590305] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The endoplasmic reticulum (ER) is a complex, multifunctional organelle comprised of a continuous membrane and lumen that is organized into a number of functional regions. It plays various roles including protein translocation, folding, quality control, secretion, calcium signaling, and lipid biogenesis. Cellular protein homeostasis is maintained by a complicated chaperone network, and the largest functional family within this network consists of proteins containing tetratricopeptide repeats (TPRs). TPRs are well-studied structural motifs that mediate intermolecular protein-protein interactions, supporting interactions with a wide range of ligands or substrates. Seven TPR-containing proteins have thus far been shown to localize to the ER and control protein organization and homeostasis within this multifunctional organelle. Here, we discuss the roles of these proteins in controlling ER processes and organization. The crucial roles that TPR-containing proteins play in the ER are highlighted by diseases or defects associated with their mutation or disruption.
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Affiliation(s)
- Jill B Graham
- a Molecular Cellular Biology Program , University of Massachusetts , Amherst , MA , USA.,b Biochemistry and Molecular Biology Department , University of Massachusetts , Amherst , MA , USA
| | - Nathan P Canniff
- a Molecular Cellular Biology Program , University of Massachusetts , Amherst , MA , USA.,b Biochemistry and Molecular Biology Department , University of Massachusetts , Amherst , MA , USA
| | - Daniel N Hebert
- a Molecular Cellular Biology Program , University of Massachusetts , Amherst , MA , USA.,b Biochemistry and Molecular Biology Department , University of Massachusetts , Amherst , MA , USA
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5
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Benarroch R, Austin JM, Ahmed F, Isaacson RL. The roles of cytosolic quality control proteins, SGTA and the BAG6 complex, in disease. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2019; 114:265-313. [PMID: 30635083 PMCID: PMC7102839 DOI: 10.1016/bs.apcsb.2018.11.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
SGTA is a co-chaperone that, in collaboration with the complex of BAG6/UBL4A/TRC35, facilitates the biogenesis and quality control of hydrophobic proteins, protecting them from the aqueous cytosolic environment. This work includes targeting tail-anchored proteins to their resident membranes, sorting of membrane and secretory proteins that mislocalize to the cytoplasm and endoplasmic reticulum-associated degradation of misfolded proteins. Since these functions are all vital for the cell's continued proteostasis, their disruption poses a threat to the cell, with a particular risk of protein aggregation, a phenomenon that underpins many diseases. Although the specific disease implications of machinery involved in quality control of hydrophobic substrates are poorly understood, here we summarize much of the available information on this topic.
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Affiliation(s)
- Rashi Benarroch
- Department of Chemistry, King's College London, London, United Kingdom
| | - Jennifer M Austin
- Department of Chemistry, King's College London, London, United Kingdom
| | - Fahmeda Ahmed
- Department of Chemistry, King's College London, London, United Kingdom
| | - Rivka L Isaacson
- Department of Chemistry, King's College London, London, United Kingdom.
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6
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Bernadotte A, Kumar R, Winblad B, Pavlov PF. In silico identification and biochemical characterization of the human dicarboxylate clamp TPR protein interaction network. FEBS Open Bio 2018; 8:1830-1843. [PMID: 30410862 PMCID: PMC6212638 DOI: 10.1002/2211-5463.12521] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Revised: 08/31/2018] [Accepted: 09/03/2018] [Indexed: 11/16/2022] Open
Abstract
Dicarboxylate clamp tetratricopeptide repeat (dcTPR) motif‐containing proteins are well‐known partners of the heat shock protein (Hsp) 70 and Hsp90 molecular chaperones. Together, they facilitate a variety of intracellular processes, including protein folding and maturation, protein targeting, and protein degradation. An extreme C‐terminal sequence, the EEVD motif, is identical in Hsp70 and Hsp90, and is indispensable for their interaction with dcTPR proteins. However, almost no information is available on the existence of other potential dcTPR‐interacting proteins. We searched the human protein database for proteins with C‐terminal sequences similar to that of Hsp70/Hsp90 to identify potential partners of dcTPR proteins. The search identified 112 proteins containing a Hsp70/Hsp90‐like signature at their C termini. Gene Ontology enrichment analysis of identified proteins revealed enrichment of distinct protein classes, such as molecular chaperones and proteins of the ubiquitin–proteasome system, highlighting the possibility of functional specialization of proteins containing a Hsp70/Hsp90‐like signature. We confirmed interactions of selected proteins containing Hsp70/Hsp90‐like C termini with dcTPR proteins both in vitro and in situ. Analysis of interactions of 10‐amino‐acid peptides corresponding to the C termini of identified proteins with dcTPR proteins revealed significant differences in binding strength between various peptides. We propose a hierarchical mode of interaction within the dcTPR protein network. These findings describe a novel dcTPR protein interaction networks and provide a rationale for selective regulation of protein–protein interactions within this network.
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Affiliation(s)
- Alexandra Bernadotte
- Department of Molecular Biochemistry and Biophysics Karolinska Institutet Solna Sweden.,Faculty of Mechanics and Mathematics Lomonosov Moscow State University Russia
| | - Rajnish Kumar
- Division of Neurogeriatrics Department of Neuroscience Care and Society Karolinska Institutet Huddinge Sweden
| | - Bengt Winblad
- Division of Neurogeriatrics Department of Neuroscience Care and Society Karolinska Institutet Huddinge Sweden.,Memory Clinic Theme Aging Karolinska University Hospital Huddinge Sweden
| | - Pavel F Pavlov
- Division of Neurogeriatrics Department of Neuroscience Care and Society Karolinska Institutet Huddinge Sweden.,Memory Clinic Theme Aging Karolinska University Hospital Huddinge Sweden
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7
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Martínez-Lumbreras S, Krysztofinska EM, Thapaliya A, Spilotros A, Matak-Vinkovic D, Salvadori E, Roboti P, Nyathi Y, Muench JH, Roessler MM, Svergun DI, High S, Isaacson RL. Structural complexity of the co-chaperone SGTA: a conserved C-terminal region is implicated in dimerization and substrate quality control. BMC Biol 2018; 16:76. [PMID: 29996828 PMCID: PMC6042327 DOI: 10.1186/s12915-018-0542-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Accepted: 06/20/2018] [Indexed: 11/17/2022] Open
Abstract
BACKGROUND Protein quality control mechanisms are essential for cell health and involve delivery of proteins to specific cellular compartments for recycling or degradation. In particular, stray hydrophobic proteins are captured in the aqueous cytosol by a co-chaperone, the small glutamine-rich, tetratricopeptide repeat-containing protein alpha (SGTA), which facilitates the correct targeting of tail-anchored membrane proteins, as well as the sorting of membrane and secretory proteins that mislocalize to the cytosol and endoplasmic reticulum-associated degradation. Full-length SGTA has an unusual elongated dimeric structure that has, until now, evaded detailed structural analysis. The C-terminal region of SGTA plays a key role in binding a broad range of hydrophobic substrates, yet in contrast to the well-characterized N-terminal and TPR domains, there is a lack of structural information on the C-terminal domain. In this study, we present new insights into the conformation and organization of distinct domains of SGTA and show that the C-terminal domain possesses a conserved region essential for substrate processing in vivo. RESULTS We show that the C-terminal domain region is characterized by α-helical propensity and an intrinsic ability to dimerize independently of the N-terminal domain. Based on the properties of different regions of SGTA that are revealed using cell biology, NMR, SAXS, Native MS, and EPR, we observe that its C-terminal domain can dimerize in the full-length protein and propose that this reflects a closed conformation of the substrate-binding domain. CONCLUSION Our results provide novel insights into the structural complexity of SGTA and provide a new basis for mechanistic studies of substrate binding and release at the C-terminal region.
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Affiliation(s)
| | - Ewelina M Krysztofinska
- Department of Chemistry, King's College London, Britannia House, Trinity Street, London, SE1 1DB, UK
| | - Arjun Thapaliya
- Department of Chemistry, King's College London, Britannia House, Trinity Street, London, SE1 1DB, UK
| | - Alessandro Spilotros
- European Molecular Biology Laboratory, Hamburg Outstation, Notkestrasse 85, 22603, Hamburg, Germany
| | - Dijana Matak-Vinkovic
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, UK
| | - Enrico Salvadori
- School of Biological and Chemical Sciences, Queen Mary University of London, Mile End Road, London, E1 4NS, UK
- London Centre for Nanotechnology, University College London, 17-19 Gordon Street, London, WC1H 0AH, UK
| | - Peristera Roboti
- School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, The Michael Smith Building, Oxford Road, Manchester, M13 9PT, UK
| | - Yvonne Nyathi
- School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, The Michael Smith Building, Oxford Road, Manchester, M13 9PT, UK
- Present Address: School of Life Sciences, University of Lincoln, Joseph Banks Laboratories, Green Lane, Lincoln, LN6 7DL, UK
| | - Janina H Muench
- Department of Chemistry, King's College London, Britannia House, Trinity Street, London, SE1 1DB, UK
| | - Maxie M Roessler
- School of Biological and Chemical Sciences, Queen Mary University of London, Mile End Road, London, E1 4NS, UK
| | - Dmitri I Svergun
- European Molecular Biology Laboratory, Hamburg Outstation, Notkestrasse 85, 22603, Hamburg, Germany
| | - Stephen High
- School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, The Michael Smith Building, Oxford Road, Manchester, M13 9PT, UK
| | - Rivka L Isaacson
- Department of Chemistry, King's College London, Britannia House, Trinity Street, London, SE1 1DB, UK.
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8
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Abstract
Proper localization of membrane proteins is essential for the function of biological membranes and for the establishment of organelle identity within a cell. Molecular machineries that mediate membrane protein biogenesis need to not only achieve a high degree of efficiency and accuracy, but also prevent off-pathway aggregation events that can be detrimental to cells. The posttranslational targeting of tail-anchored proteins (TAs) provides tractable model systems to probe these fundamental issues. Recent advances in understanding TA-targeting pathways reveal sophisticated molecular machineries that drive and regulate these processes. These findings also suggest how an interconnected network of targeting factors, cochaperones, and quality control machineries together ensures robust membrane protein biogenesis.
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Affiliation(s)
- Un Seng Chio
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125; , ,
| | - Hyunju Cho
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125; , ,
| | - Shu-Ou Shan
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125; , ,
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9
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Speziali G, Liesinger L, Gindlhuber J, Leopold C, Pucher B, Brandi J, Castagna A, Tomin T, Krenn P, Thallinger GG, Olivieri O, Martinelli N, Kratky D, Schittmayer M, Birner-Gruenberger R, Cecconi D. Myristic acid induces proteomic and secretomic changes associated with steatosis, cytoskeleton remodeling, endoplasmic reticulum stress, protein turnover and exosome release in HepG2 cells. J Proteomics 2018; 181:118-130. [PMID: 29654920 DOI: 10.1016/j.jprot.2018.04.008] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Revised: 03/19/2018] [Accepted: 04/09/2018] [Indexed: 01/08/2023]
Abstract
Myristic acid, the 14-carbon saturated fatty acid (C14:0), is associated to an increased cardiovascular disease risk. Since it is found in low concentration in cells, its specific properties have not been fully analyzed. The aim of this study was to explore the cell response to this fatty acid to help explaining clinical findings on the relationship between C14:0 and cardiovascular disease. The human liver HepG2 cell line was used to investigate the hepatic response to C14:0 in a combined proteomic and secretomic approach. A total of 47 intracellular and 32 secreted proteins were deregulated after treatments with different concentrations of C14:0. Data are available via ProteomeXchange (PXD007902). In addition, C14:0 treatment of primary murine hepatocytes confirmed that C14:0 induces lipid droplet accumulation and elevates perilipin-2 levels. Functional enrichment analysis revealed that C14:0 modulates lipid droplet formation and cytoskeleton organization, induce ER stress, changes in exosome and extracellular miRNA sorting in HepG2cells. Our data provide for the first time a proteomic profiling of the effects of C14:0 in human hepatoma cells and contribute to the elucidation of molecular mechanisms through which this fatty acid may cause adverse health effects. BIOLOGICAL SIGNIFICANCE Myristic acid is correlated with an increase in plasma cholesterol and mortality due to cardiovascular diseases. This study is the first example of an integration of proteomic and secretomic analysis of HepG2 cells to investigate the specific properties and functional roles of myristic acid on hepatic cells. Our analyses will lead to a better understanding of the myristic acid induced effects and can elicit new diagnostic and treatment strategies based on altered proteins.
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Affiliation(s)
- Giulia Speziali
- Department of Biotechnology, Proteomics and Mass Spectrometry Laboratory, University of Verona, Strada le Grazie 15, Verona, Italy
| | - Laura Liesinger
- Research Unit of Functional Proteomics and Metabolic Pathways, Institute of Pathology, Medical University of Graz, Graz, Austria; Omics Center Graz, BioTechMed-Graz, Graz, Austria
| | - Juergen Gindlhuber
- Research Unit of Functional Proteomics and Metabolic Pathways, Institute of Pathology, Medical University of Graz, Graz, Austria; Omics Center Graz, BioTechMed-Graz, Graz, Austria
| | - Christina Leopold
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - Bettina Pucher
- Research Unit of Functional Proteomics and Metabolic Pathways, Institute of Pathology, Medical University of Graz, Graz, Austria; Omics Center Graz, BioTechMed-Graz, Graz, Austria; Institute of Computational Biotechnology, Graz University of Technology, Graz, Austria
| | - Jessica Brandi
- Department of Biotechnology, Proteomics and Mass Spectrometry Laboratory, University of Verona, Strada le Grazie 15, Verona, Italy
| | - Annalisa Castagna
- Department of Medicine, Unit of Internal Medicine, University of Verona, P.le L.A. Scuro 10, Verona, Italy
| | - Tamara Tomin
- Research Unit of Functional Proteomics and Metabolic Pathways, Institute of Pathology, Medical University of Graz, Graz, Austria; Omics Center Graz, BioTechMed-Graz, Graz, Austria
| | - Petra Krenn
- Research Unit of Functional Proteomics and Metabolic Pathways, Institute of Pathology, Medical University of Graz, Graz, Austria; Omics Center Graz, BioTechMed-Graz, Graz, Austria
| | - Gerhard G Thallinger
- Omics Center Graz, BioTechMed-Graz, Graz, Austria; Institute of Computational Biotechnology, Graz University of Technology, Graz, Austria
| | - Oliviero Olivieri
- Department of Medicine, Unit of Internal Medicine, University of Verona, P.le L.A. Scuro 10, Verona, Italy
| | - Nicola Martinelli
- Department of Medicine, Unit of Internal Medicine, University of Verona, P.le L.A. Scuro 10, Verona, Italy
| | - Dagmar Kratky
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria; BioTechMed-Graz, Graz, Austria
| | - Matthias Schittmayer
- Research Unit of Functional Proteomics and Metabolic Pathways, Institute of Pathology, Medical University of Graz, Graz, Austria; Omics Center Graz, BioTechMed-Graz, Graz, Austria; Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria; BioTechMed-Graz, Graz, Austria
| | - Ruth Birner-Gruenberger
- Research Unit of Functional Proteomics and Metabolic Pathways, Institute of Pathology, Medical University of Graz, Graz, Austria; Omics Center Graz, BioTechMed-Graz, Graz, Austria; Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria; BioTechMed-Graz, Graz, Austria.
| | - Daniela Cecconi
- Department of Biotechnology, Proteomics and Mass Spectrometry Laboratory, University of Verona, Strada le Grazie 15, Verona, Italy.
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10
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Krysztofinska EM, Evans NJ, Thapaliya A, Murray JW, Morgan RML, Martinez-Lumbreras S, Isaacson RL. Structure and Interactions of the TPR Domain of Sgt2 with Yeast Chaperones and Ybr137wp. Front Mol Biosci 2017; 4:68. [PMID: 29075633 PMCID: PMC5641545 DOI: 10.3389/fmolb.2017.00068] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2017] [Accepted: 09/21/2017] [Indexed: 12/11/2022] Open
Abstract
Small glutamine-rich tetratricopeptide repeat-containing protein 2 (Sgt2) is a multi-module co-chaperone involved in several protein quality control pathways. The TPR domain of Sgt2 and several other proteins, including SGTA, Hop, and CHIP, is a highly conserved motif known to form transient complexes with molecular chaperones such as Hsp70 and Hsp90. In this work, we present the first high resolution crystal structures of Sgt2_TPR alone and in complex with a C-terminal peptide PTVEEVD from heat shock protein, Ssa1. Using nuclear magnetic resonance spectroscopy and isothermal titration calorimetry, we demonstrate that Sgt2_TPR interacts with peptides corresponding to the C-termini of Ssa1, Hsc82, and Ybr137wp with similar binding modes and affinities.
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Affiliation(s)
| | - Nicola J Evans
- Department of Chemistry, King's College London, London, United Kingdom
| | - Arjun Thapaliya
- Department of Chemistry, King's College London, London, United Kingdom
| | - James W Murray
- Department of Life Sciences, Imperial College London, South Kensington, United Kingdom
| | - Rhodri M L Morgan
- Department of Life Sciences, Imperial College London, South Kensington, United Kingdom
| | | | - Rivka L Isaacson
- Department of Chemistry, King's College London, London, United Kingdom
| |
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