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Jing Z, Wu L, Pan Y, Zhang L, Zhang X, Shi D, Shi H, Chen J, Ji Z, Zhang J, Feng T, Tian J, Feng L. Rotavirus infection inhibits SLA-I expression on the cell surface by degrading β2 M via ERAD-proteasome pathway. Vet Microbiol 2024; 292:110036. [PMID: 38458048 DOI: 10.1016/j.vetmic.2024.110036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2024] [Revised: 02/20/2024] [Accepted: 03/01/2024] [Indexed: 03/10/2024]
Abstract
Group A Rotavirus (RVA) is a major cause of diarrhea in infants and piglets. β2-microglobulin (β2 M), encoded by the B2M gene, serves as a crucial subunit of the major histocompatibility complex class I (MHC-I) molecules. β2 M is indispensable for the transport of MHC-I to the cell membrane. MHC-I, also known as swine leukocyte antigen class I (SLA-I) in pigs, presents viral antigens to the cell surface. In this study, RVA infection down-regulated β2 M expression in both porcine intestinal epithelial cells-J2 (IPEC-J2) and MA-104 cells. RVA infection did not down-regulate the mRNA level of the B2M gene, indicating that the down-regulation of β2 M occurred on the protein level. Mechanismly, RVA infection triggered β2 M aggregation in the endoplasmic reticulum (ER) and enhanced the Lys48 (K48)-linked ubiquitination of β2 M, leading to the degradation of β2 M through ERAD-proteasome pathway. Furthermore, we found that RVA infection significantly impeded the level of SLA-I on the surface, and the overexpression of β2 M could recover its expression. In this study, our study demonstrated that RVA infection degrades β2 M via ERAD-proteasome pathway, consequently hampering SLA-I expression on the cell surface. This study would enhance the understanding of the mechanism of how RVA infection induces immune escape.
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Affiliation(s)
- Zhaoyang Jing
- State Key Laboratory for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Harbin, People's Republic of China
| | - Ling Wu
- State Key Laboratory for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Harbin, People's Republic of China
| | - Yudi Pan
- State Key Laboratory for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Harbin, People's Republic of China
| | - Liaoyuan Zhang
- State Key Laboratory for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Harbin, People's Republic of China
| | - Xin Zhang
- State Key Laboratory for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Harbin, People's Republic of China
| | - Da Shi
- State Key Laboratory for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Harbin, People's Republic of China
| | - Hongyan Shi
- State Key Laboratory for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Harbin, People's Republic of China
| | - Jianfei Chen
- State Key Laboratory for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Harbin, People's Republic of China
| | - Zhaoyang Ji
- State Key Laboratory for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Harbin, People's Republic of China
| | - Jiyu Zhang
- State Key Laboratory for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Harbin, People's Republic of China
| | - Tingshuai Feng
- State Key Laboratory for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Harbin, People's Republic of China
| | - Jin Tian
- State Key Laboratory for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Harbin, People's Republic of China.
| | - Li Feng
- State Key Laboratory for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Harbin, People's Republic of China.
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2
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Suzuki R, Mattos DR, Kitamura T, Tsujioka R, Kobayashi K, Inuki S, Ohno H, Ishmael JE, McPhail KL, Oishi S. Design of Synthetic Surrogates for the Macrolactone Linker Motif in Coibamide A. ACS Med Chem Lett 2023; 14:1344-1350. [PMID: 37849553 PMCID: PMC10578308 DOI: 10.1021/acsmedchemlett.3c00232] [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: 05/31/2023] [Accepted: 09/13/2023] [Indexed: 10/19/2023] Open
Abstract
A marine cyanobacterial cyclic depsipeptide, coibamide A (CbA), inhibits the mammalian protein secretory pathway by blocking the Sec61 translocon, which is an emerging drug target for cancer and other chronic diseases. In our previous structure-activity relationship study of CbA, the macrolactone ester linker was replaced with alkyl/alkenyl surrogates to provide synthetically accessible macrocyclic scaffolds. To optimize the cellular bioactivity profile of CbA analogues, novel lysine mimetics having β- and ε-methyl groups have now been designed and synthesized by a stereoselective route. A significant increase in cytotoxicity was observed upon introduction of these two methyl groups, corresponding to the d-MeAla α-methyl and MeThr β-methyl of CbA. All synthetic products retained the ability to inhibit secretion of a model Sec61 substrate. Tandem evaluation of secretory function inhibition in living cells and cytotoxicity was an effective strategy to assess the impact of structural modifications to the linker for ring closure.
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Affiliation(s)
- Rikito Suzuki
- Graduate
School of Pharmaceutical Sciences, Kyoto
University, Sakyo-ku, Kyoto 606-8501, Japan
- Laboratory
of Medicinal Chemistry, Kyoto Pharmaceutical
University, Yamashina-ku, Kyoto 607-8412, Japan
| | - Daphne R. Mattos
- Department
of Pharmaceutical Sciences, College of Pharmacy, Oregon State University, Corvallis, Oregon 97331, United States
| | - Takashi Kitamura
- Graduate
School of Pharmaceutical Sciences, Kyoto
University, Sakyo-ku, Kyoto 606-8501, Japan
| | - Rina Tsujioka
- Laboratory
of Medicinal Chemistry, Kyoto Pharmaceutical
University, Yamashina-ku, Kyoto 607-8412, Japan
| | - Kazuya Kobayashi
- Laboratory
of Medicinal Chemistry, Kyoto Pharmaceutical
University, Yamashina-ku, Kyoto 607-8412, Japan
| | - Shinsuke Inuki
- Graduate
School of Pharmaceutical Sciences, Kyoto
University, Sakyo-ku, Kyoto 606-8501, Japan
| | - Hiroaki Ohno
- Graduate
School of Pharmaceutical Sciences, Kyoto
University, Sakyo-ku, Kyoto 606-8501, Japan
| | - Jane E. Ishmael
- Department
of Pharmaceutical Sciences, College of Pharmacy, Oregon State University, Corvallis, Oregon 97331, United States
| | - Kerry L. McPhail
- Department
of Pharmaceutical Sciences, College of Pharmacy, Oregon State University, Corvallis, Oregon 97331, United States
| | - Shinya Oishi
- Graduate
School of Pharmaceutical Sciences, Kyoto
University, Sakyo-ku, Kyoto 606-8501, Japan
- Laboratory
of Medicinal Chemistry, Kyoto Pharmaceutical
University, Yamashina-ku, Kyoto 607-8412, Japan
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3
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Itskanov S, Wang L, Junne T, Sherriff R, Xiao L, Blanchard N, Shi WQ, Forsyth C, Hoepfner D, Spiess M, Park E. A common mechanism of Sec61 translocon inhibition by small molecules. Nat Chem Biol 2023; 19:1063-1071. [PMID: 37169959 DOI: 10.1038/s41589-023-01337-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Accepted: 04/12/2023] [Indexed: 05/13/2023]
Abstract
The Sec61 complex forms a protein-conducting channel in the endoplasmic reticulum membrane that is required for secretion of soluble proteins and production of many membrane proteins. Several natural and synthetic small molecules specifically inhibit Sec61, generating cellular effects that are useful for therapeutic purposes, but their inhibitory mechanisms remain unclear. Here we present near-atomic-resolution structures of human Sec61 inhibited by a comprehensive panel of structurally distinct small molecules-cotransin, decatransin, apratoxin, ipomoeassin, mycolactone, cyclotriazadisulfonamide and eeyarestatin. All inhibitors bind to a common lipid-exposed pocket formed by the partially open lateral gate and plug domain of Sec61. Mutations conferring resistance to the inhibitors are clustered at this binding pocket. The structures indicate that Sec61 inhibitors stabilize the plug domain in a closed state, thereby preventing the protein-translocation pore from opening. Our study provides the atomic details of Sec61-inhibitor interactions and the structural framework for further pharmacological studies and drug design.
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Affiliation(s)
- Samuel Itskanov
- Biophysics Graduate Program, University of California, Berkeley, Berkeley, CA, USA
| | - Laurie Wang
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA, USA
| | - Tina Junne
- Biozentrum, University of Basel, Basel, Switzerland
| | - Rumi Sherriff
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA, USA
| | - Li Xiao
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH, USA
| | - Nicolas Blanchard
- Université de Haute-Alsace, Université de Strasbourg, CNRS, LIMA, UMR 7042, Mulhouse, France
| | - Wei Q Shi
- Department of Chemistry, Ball State University, Muncie, IN, USA
| | - Craig Forsyth
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH, USA
| | - Dominic Hoepfner
- Novartis Institutes for BioMedical Research, Novartis Pharma AG, Forum 1 Novartis Campus, Basel, Switzerland
| | | | - Eunyong Park
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA, USA.
- California Institute for Quantitative Biosciences, University of California, Berkeley, Berkeley, CA, USA.
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4
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Zeng K, Zeng Y, Zhan H, Zhan Z, Wang L, Xie Y, Tang Y, Li C, Chen Y, Li S, Liu M, Chen X, Liang L, Deng F, Song Y, Zhou A. SEC61G assists EGFR-amplified glioblastoma to evade immune elimination. Proc Natl Acad Sci U S A 2023; 120:e2303400120. [PMID: 37523556 PMCID: PMC10410745 DOI: 10.1073/pnas.2303400120] [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: 03/03/2023] [Accepted: 07/06/2023] [Indexed: 08/02/2023] Open
Abstract
Amplification of chromosome 7p11 (7p11) is the most common alteration in primary glioblastoma (GBM), resulting in gains of epidermal growth factor receptor (EGFR) copy number in 50 to 60% of GBM tumors. However, treatment strategies targeting EGFR have thus far failed in clinical trials, and the underlying mechanism remains largely unclear. We here demonstrate that EGFR amplification at the 7p11 locus frequently encompasses its neighboring genes and identifies SEC61G as a critical regulator facilitating GBM immune evasion and tumor growth. We found that SEC61G is always coamplified with EGFR and is highly expressed in GBM. As an essential subunit of the SEC61 translocon complex, SEC61G promotes translocation of newly translated immune checkpoint ligands (ICLs, including PD-L1, PVR, and PD-L2) into the endoplasmic reticulum and promotes their glycosylation, stabilization, and membrane presentation. Depletion of SEC61G promotes the infiltration and cytolytic activity of CD8+ T cells and thus inhibits GBM occurrence. Further, SEC61G inhibition augments the therapeutic efficiency of EGFR tyrosine kinase inhibitors in mice. Our study demonstrates a critical role of SEC61G in GBM immune evasion, which provides a compelling rationale for combination therapy of EGFR-amplified GBMs.
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Affiliation(s)
- Kunlin Zeng
- Department of Cell Biology, School of Basic Medical Science, Southern Medical University, Guangzhou510515, China
| | - Yu Zeng
- Department of Cell Biology, School of Basic Medical Science, Southern Medical University, Guangzhou510515, China
| | - Hongchao Zhan
- Department of Cell Biology, School of Basic Medical Science, Southern Medical University, Guangzhou510515, China
| | - Ziling Zhan
- Department of Cell Biology, School of Basic Medical Science, Southern Medical University, Guangzhou510515, China
| | - Li Wang
- Department of Cell Biology, School of Basic Medical Science, Southern Medical University, Guangzhou510515, China
| | - Yuxin Xie
- Department of Cell Biology, School of Basic Medical Science, Southern Medical University, Guangzhou510515, China
| | - Yanqing Tang
- Department of Cell Biology, School of Basic Medical Science, Southern Medical University, Guangzhou510515, China
| | - Cuiying Li
- Department of Cell Biology, School of Basic Medical Science, Southern Medical University, Guangzhou510515, China
| | - Yanwen Chen
- Department of Cell Biology, School of Basic Medical Science, Southern Medical University, Guangzhou510515, China
| | - Shangbiao Li
- Department of Cell Biology, School of Basic Medical Science, Southern Medical University, Guangzhou510515, China
- Department of Radiation Oncology, Zhujiang Hospital, Southern Medical University, Guangzhou510285, China
| | - Ming Liu
- Department of Cell Biology, School of Basic Medical Science, Southern Medical University, Guangzhou510515, China
| | - Xiaoxia Chen
- Department of Cell Biology, School of Basic Medical Science, Southern Medical University, Guangzhou510515, China
| | - Li Liang
- Guangdong Province Key Laboratory of Molecular Tumor Pathology, School of Basic Medical Science, Southern Medical University, Guangzhou510515, China
| | - Fan Deng
- Department of Cell Biology, School of Basic Medical Science, Southern Medical University, Guangzhou510515, China
| | - Ye Song
- Department of Neurosurgery, Nanfang Hospital, Southern Medical University, Guangzhou510515, China
| | - Aidong Zhou
- Department of Cell Biology, School of Basic Medical Science, Southern Medical University, Guangzhou510515, China
- Department of Radiation Oncology, Zhujiang Hospital, Southern Medical University, Guangzhou510285, China
- Guangdong Province Key Laboratory of Molecular Tumor Pathology, School of Basic Medical Science, Southern Medical University, Guangzhou510515, China
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5
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Mun SH, Lee CS, Kim HJ, Kim J, Lee H, Yang J, Im SH, Kim JH, Seong JK, Hwang CS. Marchf6 E3 ubiquitin ligase critically regulates endoplasmic reticulum stress, ferroptosis, and metabolic homeostasis in POMC neurons. Cell Rep 2023; 42:112746. [PMID: 37421621 DOI: 10.1016/j.celrep.2023.112746] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Revised: 05/18/2023] [Accepted: 06/19/2023] [Indexed: 07/10/2023] Open
Abstract
The metabolic prohormone pro-opiomelanocortin (POMC) is generally translocated into the endoplasmic reticulum (ER) for entry into the secretory pathway. Patients with mutations within the signal peptide (SP) of POMC or its adjoining segment develop metabolic disorders. However, the existence, metabolic fate, and functional outcomes of cytosol-retained POMC remain unclear. Here, we show that SP-uncleaved POMC is produced in the cytosol of POMC neuronal cells, thus inducing ER stress and ferroptotic cell death. Mechanistically, the cytosol-retained POMC sequesters the chaperone Hspa5 and subsequently accelerates degradation of the glutathione peroxidase Gpx4, a core regulator of ferroptosis, via the chaperone-mediated autophagy. We also show that the Marchf6 E3 ubiquitin ligase mediates the degradation of cytosol-retained POMC, thereby preventing ER stress and ferroptosis. Furthermore, POMC-Cre-mediated Marchf6-deficient mice exhibit hyperphagia, reduced energy expenditure, and weight gain. These findings suggest that Marchf6 is a critical regulator of ER stress, ferroptosis, and metabolic homeostasis in POMC neurons.
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Affiliation(s)
- Sang-Hyeon Mun
- Department of Life Sciences, Pohang University of Science and Technology, Pohang, Gyeongbuk 37673, South Korea
| | - Chang-Seok Lee
- Department of Life Sciences, Pohang University of Science and Technology, Pohang, Gyeongbuk 37673, South Korea
| | - Hyun Jin Kim
- Department of Life Sciences, Pohang University of Science and Technology, Pohang, Gyeongbuk 37673, South Korea
| | - Jiye Kim
- Korea Mouse Phenotyping Center, Seoul National University, Seoul 08826, South Korea; Laboratory of Developmental Biology and Genomics, Research Institute for Veterinary Science, and BK21 PLUS Program for Creative Veterinary Science Research, College of Veterinary Medicine, Seoul National University, Seoul 08826, South Korea; Interdisciplinary Program for Bioinformatics, Program for Cancer Biology and BIO-MAX/N-Bio Institute, Seoul National University, Seoul 08826, South Korea
| | - Haena Lee
- Department of Life Sciences, Pohang University of Science and Technology, Pohang, Gyeongbuk 37673, South Korea
| | - Jihye Yang
- Department of Life Sciences, Pohang University of Science and Technology, Pohang, Gyeongbuk 37673, South Korea
| | - Sin-Hyeog Im
- Department of Life Sciences, Pohang University of Science and Technology, Pohang, Gyeongbuk 37673, South Korea; Institute of Convergence Science, Yonsei University, Seoul 03722, South Korea; ImmunoBiome, Inc, Pohang 37666, Republic of Korea
| | - Joung-Hun Kim
- Department of Life Sciences, Pohang University of Science and Technology, Pohang, Gyeongbuk 37673, South Korea; Institute of Convergence Science, Yonsei University, Seoul 03722, South Korea
| | - Je Kyung Seong
- Korea Mouse Phenotyping Center, Seoul National University, Seoul 08826, South Korea; Laboratory of Developmental Biology and Genomics, Research Institute for Veterinary Science, and BK21 PLUS Program for Creative Veterinary Science Research, College of Veterinary Medicine, Seoul National University, Seoul 08826, South Korea; Interdisciplinary Program for Bioinformatics, Program for Cancer Biology and BIO-MAX/N-Bio Institute, Seoul National University, Seoul 08826, South Korea
| | - Cheol-Sang Hwang
- Department of Life Sciences, Korea University, Seoul 02841, South Korea.
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6
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Schäfer AB, Steenhuis M, Jim KK, Neef J, O’Keefe S, Whitehead RC, Swanton E, Wang B, Halbedel S, High S, van Dijl JM, Luirink J, Wenzel M. Dual Action of Eeyarestatin 24 on Sec-Dependent Protein Secretion and Bacterial DNA. ACS Infect Dis 2023; 9:253-269. [PMID: 36637435 PMCID: PMC9926488 DOI: 10.1021/acsinfecdis.2c00404] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Eeyarestatin 24 (ES24) is a promising new antibiotic with broad-spectrum activity. It shares structural similarity with nitrofurantoin (NFT), yet appears to have a distinct and novel mechanism: ES24 was found to inhibit SecYEG-mediated protein transport and membrane insertion in Gram-negative bacteria. However, possible additional targets have not yet been explored. Moreover, its activity was notably better against Gram-positive bacteria, for which its mechanism of action had not yet been investigated. We have used transcriptomic stress response profiling, phenotypic assays, and protein secretion analyses to investigate the mode of action of ES24 in comparison with NFT using the Gram-positive model bacterium Bacillus subtilis and have compared our findings to Gram-negative Escherichia coli. Here, we show the inhibition of Sec-dependent protein secretion in B. subtilis and additionally provide evidence for DNA damage, probably caused by the generation of reactive derivatives of ES24. Interestingly, ES24 caused a gradual dissipation of the membrane potential, which led to delocalization of cytokinetic proteins and subsequent cell elongation in E. coli. However, none of those effects were observed in B. subtilis, thereby suggesting that ES24 displays distinct mechanistic differences with respect to Gram-positive and Gram-negative bacteria. Despite its structural similarity to NFT, ES24 profoundly differed in our phenotypic analysis, which implies that it does not share the NFT mechanism of generalized macromolecule and structural damage. Importantly, ES24 outperformed NFT in vivo in a zebrafish embryo pneumococcal infection model. Our results suggest that ES24 not only inhibits the Sec translocon, but also targets bacterial DNA and, in Gram-negative bacteria, the cell membrane.
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Affiliation(s)
- Ann-Britt Schäfer
- Division
of Chemical Biology, Department of Life Sciences, Chalmers University of Technology, 412 96 Gothenburg, Sweden
| | - Maurice Steenhuis
- Molecular
Microbiology, Amsterdam Institute of Molecular and Life Sciences (AIMMS), Vrije Universiteit Amsterdam, 1081 HV Amsterdam, The Netherlands
| | - Kin Ki Jim
- Department
of Medical Microbiology and Infection Prevention, Amsterdam University Medical Centers - Location Vrije Universiteit
Amsterdam, 1081 HZ Amsterdam, The Netherlands,Amsterdam
Institute for Infection and Immunity, Amsterdam
University Medical Centers, 1081 HZ Amsterdam, The Netherlands
| | - Jolanda Neef
- Department
of Medical Microbiology, University of Groningen, University Medical Center Groningen, Hanzeplein 1, PO Box 30001, 9700 RB Groningen, The Netherlands
| | - Sarah O’Keefe
- School
of
Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester M13 9PL, United Kingdom
| | - Roger C. Whitehead
- School
of Chemistry, Faculty of Science and Engineering, University of Manchester, Manchester M13 9PL, United Kingdom
| | - Eileithyia Swanton
- School
of
Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester M13 9PL, United Kingdom
| | - Biwen Wang
- Bacterial
Cell Biology and Physiology, Swammerdam Institute for Life Sciences, University of Amsterdam, 1098 XH Amsterdam, The Netherlands
| | - Sven Halbedel
- FG11
Division of Enteropathogenic Bacteria and Legionella, Robert Koch Institute, 38855 Wernigerode, Germany,Institute
for Medical Microbiology and Hospital Hygiene, Otto von Guericke University Magdeburg, 39120 Magdeburg, Germany
| | - Stephen High
- School
of
Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester M13 9PL, United Kingdom
| | - Jan Maarten van Dijl
- Department
of Medical Microbiology, University of Groningen, University Medical Center Groningen, Hanzeplein 1, PO Box 30001, 9700 RB Groningen, The Netherlands
| | - Joen Luirink
- Molecular
Microbiology, Amsterdam Institute of Molecular and Life Sciences (AIMMS), Vrije Universiteit Amsterdam, 1081 HV Amsterdam, The Netherlands,
| | - Michaela Wenzel
- Division
of Chemical Biology, Department of Life Sciences, Chalmers University of Technology, 412 96 Gothenburg, Sweden,
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7
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Sun J, Qin F, Sun F, He P, Wei E, Wang R, Zhu F, Wang Q, Tang X, Zhang Y, Shen Z. Identification and subcellular colocalization of protein transport protein Sec61α and Sec61γ in Nosema bombycis. Gene X 2023; 851:146971. [DOI: 10.1016/j.gene.2022.146971] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 09/27/2022] [Accepted: 10/11/2022] [Indexed: 11/07/2022] Open
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8
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Endothelial METRNL determines circulating METRNL level and maintains endothelial function against atherosclerosis. Acta Pharm Sin B 2022; 13:1568-1587. [PMID: 37139425 PMCID: PMC10149902 DOI: 10.1016/j.apsb.2022.12.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2022] [Revised: 11/11/2022] [Accepted: 11/18/2022] [Indexed: 12/15/2022] Open
Abstract
METRNL is a recently identified secreted protein with emerging functions. This study is to find major cellular source of circulating METRNL and to determine METRNL novel function. Here, we show METRNL is abundant in human and mouse vascular endothelium and released by endothelial cells using endoplasmic reticulum-Golgi apparatus pathway. By creating endothelial cell-specific Metrnl knockout mice, combined with bone marrow transplantation to produce bone marrow-specific deletion of Metrnl, we demonstrate that most of circulating METRNL (approximately 75%) originates from the endothelial cells. Both endothelial and circulating METRNL decrease in atherosclerosis mice and patients. By generating endothelial cell-specific Metrnl knockout in apolipoprotein E-deficient mice, combined with bone marrow-specific deletion of Metrnl in apolipoprotein E-deficient mice, we further demonstrate that endothelial METRNL deficiency accelerates atherosclerosis. Mechanically, endothelial METRNL deficiency causes vascular endothelial dysfunction including vasodilation impairment via reducing eNOS phosphorylation at Ser1177 and inflammation activation via enhancing NFκB pathway, which promotes the susceptibility of atherosclerosis. Exogenous METRNL rescues METRNL deficiency induced endothelial dysfunction. These findings reveal that METRNL is a new endothelial substance not only determining the circulating METRNL level but also regulating endothelial function for vascular health and disease. METRNL is a therapeutic target against endothelial dysfunction and atherosclerosis.
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9
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Parys JB, Van Coppenolle F. Sec61 complex/translocon: The role of an atypical ER Ca 2+-leak channel in health and disease. Front Physiol 2022; 13:991149. [PMID: 36277220 PMCID: PMC9582130 DOI: 10.3389/fphys.2022.991149] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Accepted: 09/20/2022] [Indexed: 11/02/2023] Open
Abstract
The heterotrimeric Sec61 protein complex forms the functional core of the so-called translocon that forms an aqueous channel in the endoplasmic reticulum (ER). The primary role of the Sec61 complex is to allow protein import in the ER during translation. Surprisingly, a completely different function in intracellular Ca2+ homeostasis has emerged for the Sec61 complex, and the latter is now accepted as one of the major Ca2+-leak pathways of the ER. In this review, we first discuss the structure of the Sec61 complex and focus on the pharmacology and regulation of the Sec61 complex as a Ca2+-leak channel. Subsequently, we will pay particular attention to pathologies that are linked to Sec61 mutations, such as plasma cell deficiency and congenital neutropenia. Finally, we will explore the relevance of the Sec61 complex as a Ca2+-leak channel in various pathophysiological (ER stress, apoptosis, ischemia-reperfusion) and pathological (type 2 diabetes, cancer) settings.
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Affiliation(s)
- Jan B. Parys
- Laboratory for Molecular and Cellular Signaling, Department of Cellular and Molecular Medicine & Leuven Kanker Instituut, KU Leuven, Leuven, Belgium
| | - Fabien Van Coppenolle
- CarMeN Laboratory, INSERM, INRA, INSA Lyon, Université Claude Bernard Lyon 1, Lyon, France
- Groupement Hospitalier EST, Department of Cardiology, Hospices Civils de Lyon, Lyon, France
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10
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Regulation of protein secretion through chemical regulation of endoplasmic reticulum retention signal cleavage. Nat Commun 2022; 13:1323. [PMID: 35260576 PMCID: PMC8904541 DOI: 10.1038/s41467-022-28971-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2021] [Accepted: 02/23/2022] [Indexed: 12/12/2022] Open
Abstract
Secreted proteins, such as hormones or cytokines, are key mediators in multicellular organisms. Response of protein secretion based on transcriptional control is rather slow, as it requires transcription, translation and transport from the endoplasmic reticulum (ER) to the plasma membrane via the conventional protein secretion (CPS) pathway. An alternative regulation to provide faster response would be valuable. Here we present two genetically encoded orthogonal regulatory secretion systems, which rely on the retention of pre-synthesized proteins on the ER membrane (membER, released by a cytosolic protease) or inside the ER lumen (lumER, released by an ER-luminal protease), respectively, and their release by the chemical signal-regulated proteolytic removal of an ER-retention signal, without triggering ER stress due to protein aggregates. Design of orthogonal chemically-regulated split proteases enables the combination of signals into logic functions. Its application was demonstrated on a chemically regulated therapeutic protein secretion and regulated membrane translocation of a chimeric antigen receptor (CAR) targeting cancer antigen. Regulation of the ER escape represents a platform for the design of fast-responsive and tightly-controlled modular and scalable protein secretion system for mammalian cells. Secreted proteins, such as hormones or cytokines, are key mediators in multicellular organisms. Here the authors present two genetically encoded orthogonal regulatory secretion systems that enables inducible protein release and construction of logic gates.
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11
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Kitamura T, Suzuki R, Inuki S, Ohno H, McPhail KL, Oishi S. Design of Coibamide A Mimetics with Improved Cellular Bioactivity. ACS Med Chem Lett 2022; 13:105-110. [PMID: 35059129 PMCID: PMC8762706 DOI: 10.1021/acsmedchemlett.1c00591] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Accepted: 12/06/2021] [Indexed: 11/30/2022] Open
Abstract
Coibamide A, a cyclic depsipeptide isolated from a Panamanian marine cyanobacterium, shows potent cytotoxic activity via the inhibition of the Sec61 translocon. We designed a coibamide A mimetic in which the ester linkage between MeThr and d-MeAla in coibamide A was replaced with an alkyl linker to provide a stable macrocyclic scaffold possessing a MeLys(Me) residue. Taking advantage of a facile solid-phase synthetic approach, an structure-activity relationship (SAR) study of the newly designed macrocyclic structure was performed, with a focus on altering the pattern of N-methyl substitution and amino acid configurations. Overall, the simplified macrocyclic scaffold with an alkyl linker resulted in a significantly reduced cytotoxicity. Instead, more potent coibamide A derivatives with a β-(4-biphenylyl)alanine (Bph) group were identified after the optimization of the Tyr(Me) position in the original macrocyclic scaffold of coibamide A based on the characteristic apratoxin A substructures. The similar SAR between coibamide A and apratoxin A suggests that the binding site of the Tyr(Me) side chain at the luminal end of Sec61α may be shared.
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Affiliation(s)
- Takashi Kitamura
- Graduate
School of Pharmaceutical Sciences, Kyoto
University, Sakyo-ku, Kyoto 606-8501, Japan
| | - Rikito Suzuki
- Graduate
School of Pharmaceutical Sciences, Kyoto
University, Sakyo-ku, Kyoto 606-8501, Japan
- Department
of Medicinal Chemistry, Kyoto Pharmaceutical
University, Yamashina-ku, Kyoto 607-8412, Japan
| | - Shinsuke Inuki
- Graduate
School of Pharmaceutical Sciences, Kyoto
University, Sakyo-ku, Kyoto 606-8501, Japan
| | - Hiroaki Ohno
- Graduate
School of Pharmaceutical Sciences, Kyoto
University, Sakyo-ku, Kyoto 606-8501, Japan
| | - Kerry L. McPhail
- Department
of Pharmaceutical Sciences, College of Pharmacy, Oregon State University, Corvallis, Oregon 97331, United States
| | - Shinya Oishi
- Graduate
School of Pharmaceutical Sciences, Kyoto
University, Sakyo-ku, Kyoto 606-8501, Japan
- Department
of Medicinal Chemistry, Kyoto Pharmaceutical
University, Yamashina-ku, Kyoto 607-8412, Japan
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12
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Abstract
Mycobacterium ulcerans, the causative agent of Buruli ulcer disease, is unique among human pathogens in its capacity to produce mycolactone, a diffusible macrolide with immunosuppressive and cytotoxic properties. Recent studies have shown that mycolactone operates by inhibiting the host membrane translocation complex (Sec61), with an unprecedented potency compared to previously identified Sec61 blockers. Mycolactone binding to the pore-forming subunit of Sec61 inhibits its capacity to transport nascent secretory and membrane proteins into the endoplasmic reticulum, leading to their cytosolic degradation by the ubiquitin:proteasome system. In T lymphocytes, Sec61 blockade by mycolactone manifests as a sharp decrease in the cell's ability to express homing receptors and release cytokines following activation. Sustained exposure of human cells to mycolactone typically generates proteotoxic stress responses in their cytosol and endoplasmic reticulum (ER), ultimately inducing apoptosis. Here we describe cell-free systems for studying Sec61-mediated protein translocation that allow the impact of mycolactone on the biogenesis of secretory and membrane proteins to be probed. We also describe biological assays of mycolactone-driven inhibition of Sec61 providing rapid and sensitive means to quantitatively assess the presence of the toxin in biological samples.
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13
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Inhibitors of the Sec61 Complex and Novel High Throughput Screening Strategies to Target the Protein Translocation Pathway. Int J Mol Sci 2021; 22:ijms222112007. [PMID: 34769437 PMCID: PMC8585047 DOI: 10.3390/ijms222112007] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 10/25/2021] [Accepted: 10/29/2021] [Indexed: 02/08/2023] Open
Abstract
Proteins targeted to the secretory pathway start their intracellular journey by being transported across biological membranes such as the endoplasmic reticulum (ER). A central component in this protein translocation process across the ER is the Sec61 translocon complex, which is only intracellularly expressed and does not have any enzymatic activity. In addition, Sec61 translocon complexes are difficult to purify and to reconstitute. Screening for small molecule inhibitors impairing its function has thus been notoriously difficult. However, such translocation inhibitors may not only be valuable tools for cell biology, but may also represent novel anticancer drugs, given that cancer cells heavily depend on efficient protein translocation into the ER to support their fast growth. In this review, different inhibitors of protein translocation will be discussed, and their specific mode of action will be compared. In addition, recently published screening strategies for small molecule inhibitors targeting the whole SRP-Sec61 targeting/translocation pathway will be summarized. Of note, slightly modified assays may be used in the future to screen for substances affecting SecYEG, the bacterial ortholog of the Sec61 complex, in order to identify novel antibiotic drugs.
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14
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Pharmacological targeting of endoplasmic reticulum stress in disease. Nat Rev Drug Discov 2021; 21:115-140. [PMID: 34702991 DOI: 10.1038/s41573-021-00320-3] [Citation(s) in RCA: 176] [Impact Index Per Article: 58.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/15/2021] [Indexed: 02/08/2023]
Abstract
The accumulation of misfolded proteins in the endoplasmic reticulum (ER) leads to ER stress, resulting in activation of the unfolded protein response (UPR) that aims to restore protein homeostasis. However, the UPR also plays an important pathological role in many diseases, including metabolic disorders, cancer and neurological disorders. Over the last decade, significant effort has been invested in targeting signalling proteins involved in the UPR and an array of drug-like molecules is now available. However, these molecules have limitations, the understanding of which is crucial for their development into therapies. Here, we critically review the existing ER stress and UPR-directed drug-like molecules, highlighting both their value and their limitations.
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15
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Valosin-Containing Protein (VCP)/p97: A Prognostic Biomarker and Therapeutic Target in Cancer. Int J Mol Sci 2021; 22:ijms221810177. [PMID: 34576340 PMCID: PMC8469696 DOI: 10.3390/ijms221810177] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 09/17/2021] [Accepted: 09/18/2021] [Indexed: 01/02/2023] Open
Abstract
Valosin-containing protein (VCP)/p97, a member of the AAA+ ATPase family, is a molecular chaperone recruited to the endoplasmic reticulum (ER) membrane by binding to membrane adapters (nuclear protein localization protein 4 (NPL4), p47 and ubiquitin regulatory X (UBX) domain-containing protein 1 (UBXD1)), where it is involved in ER-associated protein degradation (ERAD). However, VCP/p97 interacts with many cofactors to participate in different cellular processes that are critical for cancer cell survival and aggressiveness. Indeed, VCP/p97 is reported to be overexpressed in many cancer types and is considered a potential cancer biomarker and therapeutic target. This review summarizes the role of VCP/p97 in different cancers and the advances in the discovery of small-molecule inhibitors with therapeutic potential, focusing on the challenges associated with cancer-related VCP mutations in the mechanisms of resistance to inhibitors.
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16
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Sicking M, Lang S, Bochen F, Roos A, Drenth JPH, Zakaria M, Zimmermann R, Linxweiler M. Complexity and Specificity of Sec61-Channelopathies: Human Diseases Affecting Gating of the Sec61 Complex. Cells 2021; 10:1036. [PMID: 33925740 PMCID: PMC8147068 DOI: 10.3390/cells10051036] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 04/15/2021] [Accepted: 04/17/2021] [Indexed: 12/14/2022] Open
Abstract
The rough endoplasmic reticulum (ER) of nucleated human cells has crucial functions in protein biogenesis, calcium (Ca2+) homeostasis, and signal transduction. Among the roughly one hundred components, which are involved in protein import and protein folding or assembly, two components stand out: The Sec61 complex and BiP. The Sec61 complex in the ER membrane represents the major entry point for precursor polypeptides into the membrane or lumen of the ER and provides a conduit for Ca2+ ions from the ER lumen to the cytosol. The second component, the Hsp70-type molecular chaperone immunoglobulin heavy chain binding protein, short BiP, plays central roles in protein folding and assembly (hence its name), protein import, cellular Ca2+ homeostasis, and various intracellular signal transduction pathways. For the purpose of this review, we focus on these two components, their relevant allosteric effectors and on the question of how their respective functional cycles are linked in order to reconcile the apparently contradictory features of the ER membrane, selective permeability for precursor polypeptides, and impermeability for Ca2+. The key issues are that the Sec61 complex exists in two conformations: An open and a closed state that are in a dynamic equilibrium with each other, and that BiP contributes to its gating in both directions in cooperation with different co-chaperones. While the open Sec61 complex forms an aqueous polypeptide-conducting- and transiently Ca2+-permeable channel, the closed complex is impermeable even to Ca2+. Therefore, we discuss the human hereditary and tumor diseases that are linked to Sec61 channel gating, termed Sec61-channelopathies, as disturbances of selective polypeptide-impermeability and/or aberrant Ca2+-permeability.
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Affiliation(s)
- Mark Sicking
- Department of Medical Biochemistry & Molecular Biology, Saarland University, D-66421 Homburg, Germany;
| | - Sven Lang
- Department of Medical Biochemistry & Molecular Biology, Saarland University, D-66421 Homburg, Germany;
| | - Florian Bochen
- Department of Otorhinolaryngology, Head and Neck Surgery, Saarland University Medical Center, D-66421 Homburg, Germany; (F.B.); (M.L.)
| | - Andreas Roos
- Department of Neuropediatrics, Essen University Hospital, D-45147 Essen, Germany;
| | - Joost P. H. Drenth
- Department of Molecular Gastroenterology and Hepatology, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands;
| | - Muhammad Zakaria
- Department of Genetics, Hazara University, Mansehra 21300, Pakistan;
| | - Richard Zimmermann
- Department of Medical Biochemistry & Molecular Biology, Saarland University, D-66421 Homburg, Germany;
| | - Maximilian Linxweiler
- Department of Otorhinolaryngology, Head and Neck Surgery, Saarland University Medical Center, D-66421 Homburg, Germany; (F.B.); (M.L.)
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17
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Oswald J, Njenga R, Natriashvili A, Sarmah P, Koch HG. The Dynamic SecYEG Translocon. Front Mol Biosci 2021; 8:664241. [PMID: 33937339 PMCID: PMC8082313 DOI: 10.3389/fmolb.2021.664241] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Accepted: 03/24/2021] [Indexed: 12/13/2022] Open
Abstract
The spatial and temporal coordination of protein transport is an essential cornerstone of the bacterial adaptation to different environmental conditions. By adjusting the protein composition of extra-cytosolic compartments, like the inner and outer membranes or the periplasmic space, protein transport mechanisms help shaping protein homeostasis in response to various metabolic cues. The universally conserved SecYEG translocon acts at the center of bacterial protein transport and mediates the translocation of newly synthesized proteins into and across the cytoplasmic membrane. The ability of the SecYEG translocon to transport an enormous variety of different substrates is in part determined by its ability to interact with multiple targeting factors, chaperones and accessory proteins. These interactions are crucial for the assisted passage of newly synthesized proteins from the cytosol into the different bacterial compartments. In this review, we summarize the current knowledge about SecYEG-mediated protein transport, primarily in the model organism Escherichia coli, and describe the dynamic interaction of the SecYEG translocon with its multiple partner proteins. We furthermore highlight how protein transport is regulated and explore recent developments in using the SecYEG translocon as an antimicrobial target.
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Affiliation(s)
- Julia Oswald
- Institute for Biochemistry and Molecular Biology, Zentrum für Biochemie und Molekulare Medizin (ZMBZ), Faculty of Medicine, Albert Ludwigs Universität Freiburg, Freiburg, Germany
| | - Robert Njenga
- Institute for Biochemistry and Molecular Biology, Zentrum für Biochemie und Molekulare Medizin (ZMBZ), Faculty of Medicine, Albert Ludwigs Universität Freiburg, Freiburg, Germany.,Faculty of Biology, Albert Ludwigs Universität Freiburg, Freiburg, Germany
| | - Ana Natriashvili
- Institute for Biochemistry and Molecular Biology, Zentrum für Biochemie und Molekulare Medizin (ZMBZ), Faculty of Medicine, Albert Ludwigs Universität Freiburg, Freiburg, Germany.,Faculty of Biology, Albert Ludwigs Universität Freiburg, Freiburg, Germany
| | - Pinku Sarmah
- Institute for Biochemistry and Molecular Biology, Zentrum für Biochemie und Molekulare Medizin (ZMBZ), Faculty of Medicine, Albert Ludwigs Universität Freiburg, Freiburg, Germany.,Faculty of Biology, Albert Ludwigs Universität Freiburg, Freiburg, Germany
| | - Hans-Georg Koch
- Institute for Biochemistry and Molecular Biology, Zentrum für Biochemie und Molekulare Medizin (ZMBZ), Faculty of Medicine, Albert Ludwigs Universität Freiburg, Freiburg, Germany
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18
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Shi Y, Zhu C, Liu Y, Lu Y, Li X, Qin B, Luo Z, Luo L, Jiang M, Zhang J, Guan G, Zheng C, You J. A Vaccination with Boosted Cross Presentation by ER-Targeted Antigen Delivery for Anti-Tumor Immunotherapy. Adv Healthc Mater 2021; 10:e2001934. [PMID: 33502831 DOI: 10.1002/adhm.202001934] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Revised: 12/17/2020] [Indexed: 12/16/2022]
Abstract
Vaccination is a widely-accepted resort against the invasion or proliferation of bacteria, parasites, viruses, and even cancer, which accounts heavily on an active involvement of CD8+ T cells. As one of the pivotal strategies taken by dendritic cells (DCs) to promote the responsiveness of CD8+ T cells to exogenous antigens, cross presentation culminates in an elevated overall host defense against cancer or infection. However, the precise mechanisms regulating such a process remains elusive, and current attempts to fuel cross presentation usually fail to exert efficiency. Here, model antigen OVA-loaded, endoplasmic reticulum (ER)-targeting cationic liposome (OVA@lipoT) is developed and characterized with a booster effect on the activation and maturation of DCs. Moreover, OVA@lipoT pulsed DCs exhibit overwhelming superiority in triggering cytotoxic T lymphocyte response both in vivo and in vitro. Data reveal that lipoT alters the intracellular trafficking and presenting pathway of antigen, which promotes cross presentation and bears close relationship to the ER-associated degradation (ERAD). These results may drop a hint about the interconnectivity between cross presentation and ER-targeted antigen delivery, provide extra information to the understanding of ERAD-mediated cross priming, and even shed new light on the design and optimization of vaccines against currently intractable cancers or virus-infection.
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Affiliation(s)
- Yingying Shi
- College of Pharmaceutical Sciences Zhejiang University Zhejiang 310058 P. R. China
| | - Chunqi Zhu
- College of Pharmaceutical Sciences Zhejiang University Zhejiang 310058 P. R. China
| | - Yu Liu
- College of Pharmaceutical Sciences Zhejiang University Zhejiang 310058 P. R. China
| | - Yichao Lu
- College of Pharmaceutical Sciences Zhejiang University Zhejiang 310058 P. R. China
| | - Xiang Li
- College of Pharmaceutical Sciences Zhejiang University Zhejiang 310058 P. R. China
| | - Bing Qin
- College of Pharmaceutical Sciences Zhejiang University Zhejiang 310058 P. R. China
| | - Zhenyu Luo
- College of Pharmaceutical Sciences Zhejiang University Zhejiang 310058 P. R. China
| | - Lihua Luo
- College of Pharmaceutical Sciences Zhejiang University Zhejiang 310058 P. R. China
| | - Mengshi Jiang
- College of Pharmaceutical Sciences Zhejiang University Zhejiang 310058 P. R. China
| | - Junlei Zhang
- College of Pharmaceutical Sciences Zhejiang University Zhejiang 310058 P. R. China
| | - Guannan Guan
- College of Pharmaceutical Sciences Zhejiang University Zhejiang 310058 P. R. China
| | - Cheng Zheng
- Zhejiang Institute for Food and Drug Control Zhejiang 310058 P. R. China
| | - Jian You
- College of Pharmaceutical Sciences Zhejiang University Zhejiang 310058 P. R. China
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19
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Du R, Sullivan DK, Azizian NG, Liu Y, Li Y. Inhibition of ERAD synergizes with FTS to eradicate pancreatic cancer cells. BMC Cancer 2021; 21:237. [PMID: 33676427 PMCID: PMC7937230 DOI: 10.1186/s12885-021-07967-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Accepted: 02/22/2021] [Indexed: 02/06/2023] Open
Abstract
Background Pancreatic ductal adenocarcinoma (PDAC), one of the most lethal cancers, is driven by oncogenic KRAS mutations. Farnesyl thiosalicylic acid (FTS), also known as salirasib, is a RAS inhibitor that selectively dislodges active RAS proteins from cell membrane, inhibiting downstream signaling. FTS has demonstrated limited therapeutic efficacy in PDAC patients despite being well tolerated. Methods To improve the efficacy of FTS in PDAC, we performed a genome-wide CRISPR synthetic lethality screen to identify genetic targets that synergize with FTS treatment. Among the top candidates, multiple genes in the endoplasmic reticulum-associated protein degradation (ERAD) pathway were identified. The role of ERAD inhibition in enhancing the therapeutic efficacy of FTS was further investigated in pancreatic cancer cells using pharmaceutical and genetic approaches. Results In murine and human PDAC cells, FTS induced unfolded protein response (UPR), which was further augmented upon treatment with a chemical inhibitor of ERAD, Eeyarestatin I (EerI). Combined treatment with FTS and EerI significantly upregulated the expression of UPR marker genes and induced apoptosis in pancreatic cancer cells. Furthermore, CRISPR-based genetic ablation of the key ERAD components, HRD1 and SEL1L, sensitized PDAC cells to FTS treatment. Conclusion Our study reveals a critical role for ERAD in therapeutic response of FTS and points to the modulation of UPR as a novel approach to improve the efficacy of FTS in PDAC treatment. Supplementary Information The online version contains supplementary material available at 10.1186/s12885-021-07967-6.
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Affiliation(s)
- Rong Du
- Center for Immunotherapy Research, Houston Methodist Research Institute, Houston, TX, 77030, USA.,Department of Medicine, Weill Cornell Medical College, New York, NY, 10065, USA.,Department of Neurosurgery, Xiangya Hospital, Central South University, Changsha, 410008, Hunan, China
| | - Delaney K Sullivan
- UCLA-Caltech Medical Scientist Training Program, David Geffen School of Medicine, University of California, Los Angeles, CA, 90095, USA
| | - Nancy G Azizian
- Center for Immunotherapy Research, Houston Methodist Research Institute, Houston, TX, 77030, USA.,Department of Medicine, Weill Cornell Medical College, New York, NY, 10065, USA
| | - Yuanhui Liu
- Center for Immunotherapy Research, Houston Methodist Research Institute, Houston, TX, 77030, USA.,Department of Medicine, Weill Cornell Medical College, New York, NY, 10065, USA
| | - Yulin Li
- Center for Immunotherapy Research, Houston Methodist Research Institute, Houston, TX, 77030, USA. .,Department of Medicine, Weill Cornell Medical College, New York, NY, 10065, USA.
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20
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Zong G, Hu Z, Duah KB, Andrews LE, Zhou J, O'Keefe S, Whisenhunt L, Shim JS, Du Y, High S, Shi WQ. Ring Expansion Leads to a More Potent Analogue of Ipomoeassin F. J Org Chem 2020; 85:16226-16235. [PMID: 33264019 PMCID: PMC7808706 DOI: 10.1021/acs.joc.0c01659] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
![]()
Two
new ring-size-varying analogues (2 and 3) of ipomoeassin F were synthesized and evaluated. Improved cytotoxicity
(IC50: from 1.8 nM) and in vitro protein translocation
inhibition (IC50: 35 nM) derived from ring expansion imply
that the binding pocket of Sec61α (isoform 1) can accommodate
further structural modifications, likely in the fatty acid portion.
Streamlined preparation of the key diol intermediate 5 enabled gram-scale production, allowing us to establish that ipomoeassin
F is biologically active in vivo (MTD: ∼3 mg/kg).
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Affiliation(s)
- Guanghui Zong
- Department of Chemistry and Biochemistry, University of Maryland, College Park, Maryland 20742, United States
| | - Zhijian Hu
- Angion Biomedica Corp., 51 Charles Lindbergh Boulevard, Uniondale, New York 11553, United States
| | - Kwabena Baffour Duah
- Department of Chemistry, Ball State University, Muncie, Indiana 47306, United States
| | - Lauren E Andrews
- Department of Chemistry, Ball State University, Muncie, Indiana 47306, United States
| | - Jianhong Zhou
- Department of Biological Sciences, University of Arkansas, Fayetteville, Arkansas 72701, United States
| | - Sarah O'Keefe
- School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester M13 9PT, United Kingdom
| | - Lucas Whisenhunt
- Thermo Fisher Scientific, 6173 E. Old Marion Highway, Florence, South Carolina 29501, United States
| | - Joong Sup Shim
- Faculty of Health Sciences, University of Macau, Avenida da Universidade, 999078 Taipa, Macau SAR China
| | - Yuchun Du
- Department of Biological Sciences, University of Arkansas, Fayetteville, Arkansas 72701, United States
| | - Stephen High
- School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester M13 9PT, United Kingdom
| | - Wei Q Shi
- Department of Chemistry, Ball State University, Muncie, Indiana 47306, United States
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21
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Rasaei R, Sarodaya N, Kim KS, Ramakrishna S, Hong SH. Importance of Deubiquitination in Macrophage-Mediated Viral Response and Inflammation. Int J Mol Sci 2020; 21:ijms21218090. [PMID: 33138315 PMCID: PMC7662591 DOI: 10.3390/ijms21218090] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Revised: 10/26/2020] [Accepted: 10/28/2020] [Indexed: 01/14/2023] Open
Abstract
Ubiquitination and deubiquitination play a fundamental role in the signaling pathways associated with innate and adaptive immune responses. Macrophages are key sentinels for the host defense, triggering antiviral and inflammatory responses against various invading pathogens. Macrophages recognize the genetic material of these pathogens as pathogen-associated molecular patterns (PAMPs) and danger-associated molecular patterns (DAMPs) through the activation of its pattern recognition receptors (PRRs), initiating the cascade of immune signaling, which leads to the production of pro- and anti-inflammatory cytokines that initiates the appropriate immune response. Macrophage-mediated immune response is highly regulated and tightly controlled by the ubiquitin system since its abnormal activation or dysregulation may result in the severe pathogenesis of numerous inflammatory and autoimmune diseases. Deubiquitinating enzymes (DUBs) play a crucial role in reversing the ubiquitination and controlling the magnitude of the immune response. During infection, pathogens manipulate the host defense system by regulating DUBs to obtain nutrients and increase proliferation. Indeed, the regulation of DUBs by small molecule inhibitors has been proposed as an excellent way to control aberrant activation of immune signaling molecules. This review is focused on the complex role of DUBs in macrophage-mediated immune response, exploring the potential use of DUBs as therapeutic targets in autoimmune and inflammatory diseases by virtue of small molecule DUB inhibitors.
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Affiliation(s)
- Roya Rasaei
- Department of Internal Medicine, School of Medicine, Kangwon National University, Chuncheon 24341, Korea;
| | - Neha Sarodaya
- Graduate School of Biomedical Science and Engineering, Hanyang University, Seoul 04763, Korea; (N.S.); (K.-S.K.)
| | - Kye-Seong Kim
- Graduate School of Biomedical Science and Engineering, Hanyang University, Seoul 04763, Korea; (N.S.); (K.-S.K.)
- College of Medicine, Hanyang University, Seoul 04763, Korea
| | - Suresh Ramakrishna
- Graduate School of Biomedical Science and Engineering, Hanyang University, Seoul 04763, Korea; (N.S.); (K.-S.K.)
- College of Medicine, Hanyang University, Seoul 04763, Korea
- Correspondence: or (S.R.); or (S.-H.H.)
| | - Seok-Ho Hong
- Department of Internal Medicine, School of Medicine, Kangwon National University, Chuncheon 24341, Korea;
- Correspondence: or (S.R.); or (S.-H.H.)
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22
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Steenhuis M, Koningstein GM, Oswald J, Pick T, O'Keefe S, Koch HG, Cavalié A, Whitehead RC, Swanton E, High S, Luirink J. Eeyarestatin 24 impairs SecYEG-dependent protein trafficking and inhibits growth of clinically relevant pathogens. Mol Microbiol 2020; 115:28-40. [PMID: 32798330 PMCID: PMC8273874 DOI: 10.1111/mmi.14589] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 07/29/2020] [Indexed: 02/06/2023]
Abstract
Eeyarestatin 1 (ES1) is an inhibitor of endoplasmic reticulum (ER) associated protein degradation, Sec61‐dependent Ca2+ homeostasis and protein translocation into the ER. Recently, evidence was presented showing that a smaller analog of ES1, ES24, targets the Sec61‐translocon, and captures it in an open conformation that is translocation‐incompetent. We now show that ES24 impairs protein secretion and membrane protein insertion in Escherichia coli via the homologous SecYEG‐translocon. Transcriptomic analysis suggested that ES24 has a complex mode of action, probably involving multiple targets. Interestingly, ES24 shows antibacterial activity toward clinically relevant strains. Furthermore, the antibacterial activity of ES24 is equivalent to or better than that of nitrofurantoin, a known antibiotic that, although structurally similar to ES24, does not interfere with SecYEG‐dependent protein trafficking. Like nitrofurantoin, we find that ES24 requires activation by the NfsA and NfsB nitroreductases, suggesting that the formation of highly reactive nitroso intermediates is essential for target inactivation in vivo.
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Affiliation(s)
- Maurice Steenhuis
- Department of Molecular Microbiology, Amsterdam Institute of Molecular and Life Sciences (AIMMS), Vrije Universiteit, Amsterdam, the Netherlands
| | - Gregory M Koningstein
- Department of Molecular Microbiology, Amsterdam Institute of Molecular and Life Sciences (AIMMS), Vrije Universiteit, Amsterdam, the Netherlands
| | - Julia Oswald
- Institute of Biochemistry and Molecular Biology, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Tillman Pick
- Experimental and Clinical Pharmacology and Toxicology, Saarland University, Homburg, Germany
| | - Sarah O'Keefe
- School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
| | - Hans-Georg Koch
- Institute of Biochemistry and Molecular Biology, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Adolfo Cavalié
- Experimental and Clinical Pharmacology and Toxicology, Saarland University, Homburg, Germany
| | - Roger C Whitehead
- School of Chemistry, Faculty of Science and Engineering, University of Manchester, Manchester, UK
| | - Eileithyia Swanton
- School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
| | - Stephen High
- School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
| | - Joen Luirink
- Department of Molecular Microbiology, Amsterdam Institute of Molecular and Life Sciences (AIMMS), Vrije Universiteit, Amsterdam, the Netherlands
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23
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Yu X, Wang L, Ran L, Chen X, Sheng J, Yang Y, Wu Y, Chen G, Xiong F. New insights into the mechanism of storage protein biosynthesis in wheat caryopsis under different nitrogen levels. PROTOPLASMA 2020; 257:1289-1308. [PMID: 32405873 DOI: 10.1007/s00709-020-01489-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Accepted: 02/12/2020] [Indexed: 06/11/2023]
Abstract
Effect of different nitrogen levels (0, 150, and 300 kg hm-2) at booting stage on storage protein biosynthesis and processing quality of wheat was investigated using microstructural and ultrastructural observation, RNA sequencing, and quality analysis in this study. The results showed that the storage protein genes encoding ω- and γ-gliadin and low molecular weight glutenin subunit were upregulated at N150, and the genes encoding α- or β-gliadin and avenin-like protein were upregulated at N300. Two nitrogen levels induced expression of some interesting regulating genes, such as USE1, STX1B_2_3, SEC23, SEC24, SEC61A, HSP A1_8, HSP20, and HSP90B/TRA1. These regulatory genes were enriched in the KEGG pathway protein export, SNARE interactions in vesicular transport, and protein processing in endoplasmic reticulum. The amount, morphology, and accumulation pattern of protein body in four different endosperm regions in developing caryopsis show different response to N150 and N300, of which N300 had greater influence than N150. N150 and N300 both enhanced the contents of protein components, endosperm fullness, grain hardness, and parameters of processing quality, with the latter showing a greater degree of influence. Contrary to the accumulation pattern of protein body, N300 reduced the ratio of the amount of starch granules to the area ratio of protein body to starch granule. Results suggested that the difference of different nitrogen levels affecting storage protein biosynthesis might be through affecting the expression of the encoding and regulating gene of storage protein.
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Affiliation(s)
- Xurun Yu
- Jiangsu Key Laboratory of Crop Genetics and Physiology/Co-Innovation Center for Modern Production Technology of Grain Crops, Joint International Research Laboratory of Agriculture and Agri-Product Safety of Ministry of Education of China, Yangzhou University, Yangzhou, 225009, China
| | - Leilei Wang
- Jiangsu Key Laboratory of Crop Genetics and Physiology/Co-Innovation Center for Modern Production Technology of Grain Crops, Joint International Research Laboratory of Agriculture and Agri-Product Safety of Ministry of Education of China, Yangzhou University, Yangzhou, 225009, China
| | - Liping Ran
- Guangling College of Yangzhou University, Yangzhou, China
| | - Xinyu Chen
- Jiangsu Key Laboratory of Crop Genetics and Physiology/Co-Innovation Center for Modern Production Technology of Grain Crops, Joint International Research Laboratory of Agriculture and Agri-Product Safety of Ministry of Education of China, Yangzhou University, Yangzhou, 225009, China
| | - Jieyue Sheng
- Jiangsu Key Laboratory of Crop Genetics and Physiology/Co-Innovation Center for Modern Production Technology of Grain Crops, Joint International Research Laboratory of Agriculture and Agri-Product Safety of Ministry of Education of China, Yangzhou University, Yangzhou, 225009, China
| | - Yang Yang
- Jiangsu Key Laboratory of Crop Genetics and Physiology/Co-Innovation Center for Modern Production Technology of Grain Crops, Joint International Research Laboratory of Agriculture and Agri-Product Safety of Ministry of Education of China, Yangzhou University, Yangzhou, 225009, China
| | - Yunfei Wu
- Jiangsu Key Laboratory of Crop Genetics and Physiology/Co-Innovation Center for Modern Production Technology of Grain Crops, Joint International Research Laboratory of Agriculture and Agri-Product Safety of Ministry of Education of China, Yangzhou University, Yangzhou, 225009, China
| | - Gang Chen
- Jiangsu Key Laboratory of Crop Genetics and Physiology/Co-Innovation Center for Modern Production Technology of Grain Crops, Joint International Research Laboratory of Agriculture and Agri-Product Safety of Ministry of Education of China, Yangzhou University, Yangzhou, 225009, China
| | - Fei Xiong
- Jiangsu Key Laboratory of Crop Genetics and Physiology/Co-Innovation Center for Modern Production Technology of Grain Crops, Joint International Research Laboratory of Agriculture and Agri-Product Safety of Ministry of Education of China, Yangzhou University, Yangzhou, 225009, China.
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24
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Kinetically distinct processing pathways diversify the CD8 + T cell response to a single viral epitope. Proc Natl Acad Sci U S A 2020; 117:19399-19407. [PMID: 32719124 DOI: 10.1073/pnas.2004372117] [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] [Indexed: 02/06/2023] Open
Abstract
The source proteins from which CD8+ T cell-activating peptides are derived remain enigmatic. Glycoproteins are particularly challenging in this regard owing to several potential trafficking routes within the cell. By engineering a glycoprotein-derived epitope to contain an N-linked glycosylation site, we determined that optimal CD8+ T cell expansion and function were induced by the peptides that are rapidly produced from the exceedingly minor fraction of protein mislocalized to the cytosol. In contrast, peptides derived from the much larger fraction that undergoes translocation and quality control are produced with delayed kinetics and induce suboptimal CD8+ T cell responses. This dual system of peptide generation enhances CD8+ T cell participation in diversifying both antigenicity and the kinetics of peptide display.
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25
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Structure of the Inhibited State of the Sec Translocon. Mol Cell 2020; 79:406-415.e7. [PMID: 32692975 PMCID: PMC7427319 DOI: 10.1016/j.molcel.2020.06.013] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Revised: 04/30/2020] [Accepted: 06/05/2020] [Indexed: 02/06/2023]
Abstract
Protein secretion in eukaryotes and prokaryotes involves a universally conserved protein translocation channel formed by the Sec61 complex. Unrelated small-molecule natural products and synthetic compounds inhibit Sec61 with differential effects for different substrates or for Sec61 from different organisms, making this a promising target for therapeutic intervention. To understand the mode of inhibition and provide insight into the molecular mechanism of this dynamic translocon, we determined the structure of mammalian Sec61 inhibited by the Mycobacterium ulcerans exotoxin mycolactone via electron cryo-microscopy. Unexpectedly, the conformation of inhibited Sec61 is optimal for substrate engagement, with mycolactone wedging open the cytosolic side of the lateral gate. The inability of mycolactone-inhibited Sec61 to effectively transport substrate proteins implies that signal peptides and transmembrane domains pass through the site occupied by mycolactone. This provides a foundation for understanding the molecular mechanism of Sec61 inhibitors and reveals novel features of translocon function and dynamics. The inhibited Sec translocon adopts a conformation optimal for substrate engagement The inhibitor mycolactone wedges open the lateral gate of Sec61α Mycolactone blocks the path taken by the signal peptide during engagement Resistance mutations are likely to operate by modulating translocon dynamics
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26
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Khateb A, Ronai ZA. Unfolded Protein Response in Leukemia: From Basic Understanding to Therapeutic Opportunities. Trends Cancer 2020; 6:960-973. [PMID: 32540455 DOI: 10.1016/j.trecan.2020.05.012] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Revised: 05/03/2020] [Accepted: 05/19/2020] [Indexed: 12/11/2022]
Abstract
Understanding genetic and epigenetic changes that underlie abnormal proliferation of hematopoietic stem and progenitor cells is critical for development of new approaches to monitor and treat leukemia. The unfolded protein response (UPR) is a conserved adaptive signaling pathway that governs protein folding, secretion, and energy production and serves to maintain protein homeostasis in various cellular compartments. Deregulated UPR signaling, which often occurs in hematopoietic stem cells and leukemia, defines the degree of cellular toxicity and perturbs protein homeostasis, and at the same time, offers a novel therapeutic target. Here, we review current knowledge related to altered UPR signaling in leukemia and highlight possible strategies for exploiting the UPR as treatment for this disease.
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Affiliation(s)
- Ali Khateb
- Tumor Initiation and Maintenance Program, National Cancer Institute (NCI) Designated Cancer Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037, USA
| | - Ze'ev A Ronai
- Tumor Initiation and Maintenance Program, National Cancer Institute (NCI) Designated Cancer Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037, USA.
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27
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Pradeep Yeola A, Akbar I, Baillargeon J, Mercy Ignatius Arokia Doss P, Paavilainen VO, Rangachari M. Protein translocation and retro-translocation across the endoplasmic reticulum are crucial to inflammatory effector CD4 + T cell function. Cytokine 2020; 129:154944. [PMID: 32146280 DOI: 10.1016/j.cyto.2019.154944] [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: 06/30/2019] [Revised: 11/22/2019] [Accepted: 11/23/2019] [Indexed: 10/24/2022]
Abstract
Effector CD4+ T cells can be classified by the cytokines they secrete, with T helper 1 (Th1) cells generating interferon (IFN)γ and Th17 cells secreting interleukin (IL)-17. Both Th1 and Th17 cells are strongly implicated in the initiation and chronicity of autoimmune diseases such as multiple sclerosis. The endoplasmic reticulum (ER) has been implicated as a potentially crucial site in regulating CD4+ T cell function. Secretory and transmembrane proteins are shuttled into the ER via the Sec61 translocon, where they undergo appropriate folding; misfolded proteins are retro-translocated from the ER in a p97-dependent manner. Here, we provide evidence that both processes are crucial to the secretion of inflammatory cytokines from effector CD4+ T cells. The pan-ER inhibitor eeeyarestatin-1 (ESI), which interferes with both Sec61 translocation and p97 retro-translocation, inhibited secretion of interferon (IFN)γ, interleukin (IL)-2 and tumor necrosis factor (TNF)α from Th1 cells in a dose-dependent manner. Selective inhibition of Sec61 by Apratoxin A (ApraA) revealed that ER translocation is crucial for Th1 cytokine secretion, while inhibition of p97 by NMS-873 also inhibited Th1 function, albeit to a lesser degree. By contrast, none of ESI, ApraA or NMS-873 could significantly reduce IL-17 secretion from Th17 cells. ApraA, but not NMS-873, reduced phosphorylation of Stat1 in Th1 cells, indicating the involvement of ER translocation in Th1 differentiation pathways. ApraA had modest effects on activation of the Th17 transcription factor Stat3, while NMS-873 had no effect. Interestingly, NMS-873 was able to reduce disease severity in CD4+ T cell-driven experimental autoimmune encephalomyelitis (EAE). Together, our data indicate that CD4+ T cell function, and Th1 cell function in particular, is dependent on protein translocation and dislocation across the ER.
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Affiliation(s)
- Asmita Pradeep Yeola
- axe Neurosciences, Centre de recherche du CHU de Québec - Université Laval, Quebec City, QC, Canada
| | - Irshad Akbar
- axe Neurosciences, Centre de recherche du CHU de Québec - Université Laval, Quebec City, QC, Canada
| | - Joanie Baillargeon
- axe Neurosciences, Centre de recherche du CHU de Québec - Université Laval, Quebec City, QC, Canada
| | | | | | - Manu Rangachari
- axe Neurosciences, Centre de recherche du CHU de Québec - Université Laval, Quebec City, QC, Canada; Department of Molecular Medicine, Faculty of Medicine, Laval University, Quebec City, QC, Canada.
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28
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Sui X, Pan M, Li YM. Insights into the Design of p97-targeting Small Molecules from Structural Studies on p97 Functional Mechanism. Curr Med Chem 2020; 27:298-316. [PMID: 31584361 DOI: 10.2174/0929867326666191004162411] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Revised: 08/24/2019] [Accepted: 08/27/2019] [Indexed: 12/14/2022]
Abstract
p97, also known as valosin-containing protein or CDC48, is a member of the AAA+ protein family that is highly conserved in eukaryotes. It binds to various cofactors in the body to perform its protein-unfolding function and participates in DNA repair, degradation of subcellular membrane proteins, and protein quality control pathways, among other processes. Its malfunction can lead to many diseases, such as inclusion body myopathy, associated with Paget's disease of bone and/or frontotemporal dementia, amyotrophic lateral sclerosis disease, and others. In recent years, many small-molecule inhibitors have been deployed against p97, including bis (diethyldithiocarbamate)- copper and CB-5083, which entered the first phase of clinical tests but failed. One bottleneck in the design of p97 drugs is that its molecular mechanism remains unclear. This paper summarizes recent studies on the molecular mechanisms of p97, which may lead to insight into how the next generation of small molecules targeting p97 can be designed.
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Affiliation(s)
- Xin Sui
- Department of Chemistry, Tsinghua University, Beijing 100086, China
| | - Man Pan
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, Illinois 60637, United States
| | - Yi-Ming Li
- School of Food and Biological Engineering, Hefei University of Technology, Hefei, Anhui 230009, China
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29
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Luesch H, Paavilainen VO. Natural products as modulators of eukaryotic protein secretion. Nat Prod Rep 2020; 37:717-736. [PMID: 32067014 DOI: 10.1039/c9np00066f] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Covering: up to the end of 2019Diverse natural product small molecules have allowed critical insights into processes that govern eukaryotic cells' ability to secrete cytosolically synthesized secretory proteins into their surroundings or to insert newly synthesized integral membrane proteins into the lipid bilayer of the endoplasmic reticulum. In addition, many components of the endoplasmic reticulum, required for protein homeostasis or other processes such as lipid metabolism or maintenance of calcium homeostasis, are being investigated for their potential in modulating human disease conditions such as cancer, neurodegenerative conditions and diabetes. In this review, we cover recent findings up to the end of 2019 on natural products that influence protein secretion or impact ER protein homeostasis, and serve as powerful chemical tools to understand protein flux through the mammalian secretory pathway and as leads for the discovery of new therapeutics.
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Affiliation(s)
- Hendrik Luesch
- Department of Medicinal Chemistry, Center for Natural Products, Drug Discovery and Development (CNPD3), University of Florida, P.O. Box 100485, Gainesville, Florida 32610, USA.
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30
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Steinberg R, Knüpffer L, Origi A, Asti R, Koch HG. Co-translational protein targeting in bacteria. FEMS Microbiol Lett 2019; 365:4966980. [PMID: 29790984 DOI: 10.1093/femsle/fny095] [Citation(s) in RCA: 57] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Accepted: 04/09/2018] [Indexed: 01/16/2023] Open
Abstract
About 30% of all bacterial proteins execute their function outside of the cytosol and have to be transported into or across the cytoplasmic membrane. Bacteria use multiple protein transport systems in parallel, but the majority of proteins engage two distinct targeting systems. One is the co-translational targeting by two universally conserved GTPases, the signal recognition particle (SRP) and its receptor FtsY, which deliver inner membrane proteins to either the SecYEG translocon or the YidC insertase for membrane insertion. The other targeting system depends on the ATPase SecA, which targets secretory proteins, i.e. periplasmic and outer membrane proteins, to SecYEG for their subsequent ATP-dependent translocation. While SRP selects its substrates already very early during their synthesis, the recognition of secretory proteins by SecA is believed to occur primarily after translation termination, i.e. post-translationally. In this review we highlight recent progress on how SRP recognizes its substrates at the ribosome and how the fidelity of the targeting reaction to SecYEG is maintained. We furthermore discuss similarities and differences in the SRP-dependent targeting to either SecYEG or YidC and summarize recent results that suggest that some membrane proteins are co-translationally targeted by SecA.
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Affiliation(s)
- Ruth Steinberg
- Institute of Biochemistry and Molecular Biology, Faculty of Medicine, Albert-Ludwigs University Freiburg, Stefan Meier Str. 17, Freiburg D-79104, Germany
| | - Lara Knüpffer
- Institute of Biochemistry and Molecular Biology, Faculty of Medicine, Albert-Ludwigs University Freiburg, Stefan Meier Str. 17, Freiburg D-79104, Germany
| | - Andrea Origi
- Institute of Biochemistry and Molecular Biology, Faculty of Medicine, Albert-Ludwigs University Freiburg, Stefan Meier Str. 17, Freiburg D-79104, Germany.,Faculty of Biology, Albert-Ludwigs-University Freiburg, Schänzlestr. 1, Freiburg D-79104, Germany
| | - Rossella Asti
- Institute of Biochemistry and Molecular Biology, Faculty of Medicine, Albert-Ludwigs University Freiburg, Stefan Meier Str. 17, Freiburg D-79104, Germany
| | - Hans-Georg Koch
- Institute of Biochemistry and Molecular Biology, Faculty of Medicine, Albert-Ludwigs University Freiburg, Stefan Meier Str. 17, Freiburg D-79104, Germany
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31
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Excess hepsin proteolytic activity limits oncogenic signaling and induces ER stress and autophagy in prostate cancer cells. Cell Death Dis 2019; 10:601. [PMID: 31399560 PMCID: PMC6689070 DOI: 10.1038/s41419-019-1830-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Revised: 07/05/2019] [Accepted: 07/22/2019] [Indexed: 02/06/2023]
Abstract
The serine protease hepsin is frequently overexpressed in human prostate cancer (PCa) and is associated with matrix degradation and PCa progression in mice. Curiously, low expression of hepsin is associated with poor survival in different cancer types, and transgenic overexpression of hepsin leads to loss of viability in various cancer cell lines. Here, by comparing isogenic transfectants of the PCa cell line PC-3 providing inducible overexpression of wild-type hepsin (HPN) vs. the protease-deficient mutant HPNS353A, we were able to attribute hepsin-mediated tumor-adverse effects to its excess proteolytic activity. A stem-like expression signature of surface markers and adhesion molecules, Notch intracellular domain release, and increased pericellular protease activity were associated with low expression levels of wild-type hepsin, but were partially lost in response to overexpression. Instead, overexpression of wild-type hepsin, but not of HPNS353A, induced relocalization of the protein to the cytoplasm, and increased autophagic flux in vitro as well as LC3B punctae frequency in tumor xenografts. Confocal microscopy revealed colocalization of wild-type hepsin with both LC3B punctae as well as with the autophagy cargo receptor p62/SQSTM1. Overexpression of wild type, but not protease-deficient hepsin induced expression and nuclear presence of CHOP, indicating activation of the unfolded protein response and ER-associated protein degradation (ERAD). Whereas inhibitors of ER stress and secretory protein trafficking slightly increased viability, combined inhibition of the ubiquitin-proteasome degradation pathway (by bortezomib) with either ER stress (by salubrinal) or autophagy (by bafilomycin A1) revealed a significant decrease of viability during overexpression of wild-type hepsin in PC-3 cells. Our results demonstrate that a precise control of Hepsin proteolytic activity is critical for PCa cell fate and suggest, that the interference with ERAD could be a promising therapeutic option, leading to induction of proteotoxicity in hepsin-overexpressing tumors.
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32
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Zong G, Hu Z, O’Keefe S, Tranter D, Iannotti MJ, Baron L, Hall B, Corfield K, Paatero AO, Henderson MJ, Roboti P, Zhou J, Sun X, Govindarajan M, Rohde JM, Blanchard N, Simmonds R, Inglese J, Du Y, Demangel C, High S, Paavilainen VO, Shi WQ. Ipomoeassin F Binds Sec61α to Inhibit Protein Translocation. J Am Chem Soc 2019; 141:8450-8461. [PMID: 31059257 PMCID: PMC6627486 DOI: 10.1021/jacs.8b13506] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Ipomoeassin F is a potent natural cytotoxin that inhibits growth of many tumor cell lines with single-digit nanomolar potency. However, its biological and pharmacological properties have remained largely unexplored. Building upon our earlier achievements in total synthesis and medicinal chemistry, we used chemical proteomics to identify Sec61α (protein transport protein Sec61 subunit alpha isoform 1), the pore-forming subunit of the Sec61 protein translocon, as a direct binding partner of ipomoeassin F in living cells. The interaction is specific and strong enough to survive lysis conditions, enabling a biotin analogue of ipomoeassin F to pull down Sec61α from live cells, yet it is also reversible, as judged by several experiments including fluorescent streptavidin staining, delayed competition in affinity pulldown, and inhibition of TNF biogenesis after washout. Sec61α forms the central subunit of the ER protein translocation complex, and the binding of ipomoeassin F results in a substantial, yet selective, inhibition of protein translocation in vitro and a broad ranging inhibition of protein secretion in live cells. Lastly, the unique resistance profile demonstrated by specific amino acid single-point mutations in Sec61α provides compelling evidence that Sec61α is the primary molecular target of ipomoeassin F and strongly suggests that the binding of this natural product to Sec61α is distinctive. Therefore, ipomoeassin F represents the first plant-derived, carbohydrate-based member of a novel structural class that offers new opportunities to explore Sec61α function and to further investigate its potential as a therapeutic target for drug discovery.
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Affiliation(s)
- Guanghui Zong
- †Department
of Chemistry and Biochemistry and ⬡Department of Biological Sciences, University of Arkansas, Fayetteville, Arkansas 72701, United States,Department
of Chemistry and Biochemistry, University
of Maryland, College Park, Maryland 20742, United States
| | - Zhijian Hu
- †Department
of Chemistry and Biochemistry and ⬡Department of Biological Sciences, University of Arkansas, Fayetteville, Arkansas 72701, United States
| | - Sarah O’Keefe
- School
of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, M13 9PT, United Kingdom
| | - Dale Tranter
- University
of Helsinki, HiLIFE, Helsinki, Finland,Institute
of Biotechnology, Helsinki, Finland
| | - Michael J. Iannotti
- National
Center for Advancing Translational Sciences, National
Institutes of Health, Rockville, Maryland 20850, United States
| | - Ludivine Baron
- Immunobiology
of Infection Unit, Institut Pasteur, 75015 Paris, France,INSERM, U1221, 75005 Paris, France
| | - Belinda Hall
- Department
of Microbial Sciences, School of Biosciences and Medicine, University of Surrey, Guildford, Surrey GU2 7XH, United Kingdom
| | - Katherine Corfield
- Department
of Microbial Sciences, School of Biosciences and Medicine, University of Surrey, Guildford, Surrey GU2 7XH, United Kingdom
| | - Anja O. Paatero
- University
of Helsinki, HiLIFE, Helsinki, Finland,Institute
of Biotechnology, Helsinki, Finland
| | - Mark J. Henderson
- National
Center for Advancing Translational Sciences, National
Institutes of Health, Rockville, Maryland 20850, United States
| | - Peristera Roboti
- School
of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, M13 9PT, United Kingdom
| | - Jianhong Zhou
- †Department
of Chemistry and Biochemistry and ⬡Department of Biological Sciences, University of Arkansas, Fayetteville, Arkansas 72701, United States
| | - Xianwei Sun
- †Department
of Chemistry and Biochemistry and ⬡Department of Biological Sciences, University of Arkansas, Fayetteville, Arkansas 72701, United States,Department
of Radiology, Baylor College of Medicine, Houston, Texas 77030, United States
| | - Mugunthan Govindarajan
- †Department
of Chemistry and Biochemistry and ⬡Department of Biological Sciences, University of Arkansas, Fayetteville, Arkansas 72701, United States,Emory
Institute for Drug Development, Emory University, 954 Gatewood Road, Atlanta, Georgia 30329, United States
| | - Jason M. Rohde
- National
Center for Advancing Translational Sciences, National
Institutes of Health, Rockville, Maryland 20850, United States
| | - Nicolas Blanchard
- Université
de Haute-Alsace, Université de Strasbourg, CNRS, LIMA, UMR 7042, 68000 Mulhouse, France
| | - Rachel Simmonds
- Department
of Microbial Sciences, School of Biosciences and Medicine, University of Surrey, Guildford, Surrey GU2 7XH, United Kingdom,
| | - James Inglese
- National
Center for Advancing Translational Sciences, National
Institutes of Health, Rockville, Maryland 20850, United States,
| | - Yuchun Du
- †Department
of Chemistry and Biochemistry and ⬡Department of Biological Sciences, University of Arkansas, Fayetteville, Arkansas 72701, United States,
| | - Caroline Demangel
- Immunobiology
of Infection Unit, Institut Pasteur, 75015 Paris, France,INSERM, U1221, 75005 Paris, France,
| | - Stephen High
- School
of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, M13 9PT, United Kingdom,
| | - Ville O. Paavilainen
- University
of Helsinki, HiLIFE, Helsinki, Finland,Institute
of Biotechnology, Helsinki, Finland,
| | - Wei Q. Shi
- †Department
of Chemistry and Biochemistry and ⬡Department of Biological Sciences, University of Arkansas, Fayetteville, Arkansas 72701, United States,Department
of Chemistry, Ball State University, Muncie, Indiana 47306, United States,;
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33
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Eeyarestatin Compounds Selectively Enhance Sec61-Mediated Ca 2+ Leakage from the Endoplasmic Reticulum. Cell Chem Biol 2019; 26:571-583.e6. [PMID: 30799222 PMCID: PMC6483976 DOI: 10.1016/j.chembiol.2019.01.010] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Revised: 10/06/2018] [Accepted: 01/24/2019] [Indexed: 01/01/2023]
Abstract
Eeyarestatin 1 (ES1) inhibits p97-dependent protein degradation, Sec61-dependent protein translocation into the endoplasmic reticulum (ER), and vesicular transport within the endomembrane system. Here, we show that ES1 impairs Ca2+ homeostasis by enhancing the Ca2+ leakage from mammalian ER. A comparison of various ES1 analogs suggested that the 5-nitrofuran (5-NF) ring of ES1 is crucial for this effect. Accordingly, the analog ES24, which conserves the 5-NF domain of ES1, selectively inhibited protein translocation into the ER, displayed the highest potency on ER Ca2+ leakage of ES1 analogs studied and induced Ca2+-dependent cell death. Using small interfering RNA-mediated knockdown of Sec61α, we identified Sec61 complexes as the targets that mediate the gain of Ca2+ leakage induced by ES1 and ES24. By interacting with the lateral gate of Sec61α, ES1 and ES24 likely capture Sec61 complexes in a Ca2+-permeable, open state, in which Sec61 complexes allow Ca2+ leakage but are translocation incompetent. ES1, ES2, and ES24 deplete Ca2+ in ER ESR35 and ES47 do not affect cellular Ca2+ homeostasis The most potent eeyarestatin, ES24, comprises only the 5-nitrofuran domain ES1 and ES24 target Sec61 complexes in ER
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34
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Klein W, Rutz C, Eckhard J, Provinciael B, Specker E, Neuenschwander M, Kleinau G, Scheerer P, von Kries JP, Nazaré M, Vermeire K, Schülein R. Use of a sequential high throughput screening assay to identify novel inhibitors of the eukaryotic SRP-Sec61 targeting/translocation pathway. PLoS One 2018; 13:e0208641. [PMID: 30543669 PMCID: PMC6292634 DOI: 10.1371/journal.pone.0208641] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Accepted: 11/20/2018] [Indexed: 11/22/2022] Open
Abstract
The SRP-Sec61 targeting/translocation pathway of eukaryotic cells targets nascent protein chains to the membrane of the endoplasmic reticulum. Using this machinery, secretory proteins are translocated across this membrane whereas membrane proteins are integrated into the lipid bilayer. One of the key players of the pathway is the protein-conducting Sec61 (translocon) complex of the endoplasmic reticulum. The Sec61 complex has no enzymatic activity, is expressed only intracellularly and is difficult to purify and to reconstitute. Screening for small molecule inhibitors impairing its functions is thus notoriously difficult. Such inhibitors may not only be valuable tools for cell biology, they may also represent novel anti-tumor drugs. Here we have developed a two-step, sequential screening assay for inhibitors of the whole SRP-Sec61 targeting/translocation pathway which might include molecules affecting Sec61 complex functions. The resulting hit compounds were analyzed using a whole cell biosynthesis assay and a cell free transcription/translation/translocation assay. Using this methodology, we identified novel compounds inhibiting this pathway. Following structure-based back screening, one of these substances was analyzed in more detail and we could show that it indeed impairs translocation at the level of the Sec61 complex. A slightly modified methodology may be used in the future to screen for substances affecting SecYEG, the bacterial ortholog of the Sec61 complex in order to derive novel antibiotic drugs.
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Affiliation(s)
- Wolfgang Klein
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Berlin, Germany
| | - Claudia Rutz
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Berlin, Germany
| | - Jamina Eckhard
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Berlin, Germany
| | - Becky Provinciael
- KU Leuven, Department of Microbiology and Immunology, Rega Institute, Laboratory of Virology and Chemotherapy, Leuven, Belgium
| | - Edgar Specker
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Berlin, Germany
| | | | - Gunnar Kleinau
- Charité—Universitätsmedizin Berlin, Campus Charité Mitte, Charité Centrum Grundlagenmedizin CC2, Institut für Medizinische Physik und Biophysik, Group Protein X-ray Crystallography & Signal Transduction, Berlin, Germany
| | - Patrick Scheerer
- Charité—Universitätsmedizin Berlin, Campus Charité Mitte, Charité Centrum Grundlagenmedizin CC2, Institut für Medizinische Physik und Biophysik, Group Protein X-ray Crystallography & Signal Transduction, Berlin, Germany
| | | | - Marc Nazaré
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Berlin, Germany
| | - Kurt Vermeire
- KU Leuven, Department of Microbiology and Immunology, Rega Institute, Laboratory of Virology and Chemotherapy, Leuven, Belgium
| | - Ralf Schülein
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Berlin, Germany
- * E-mail:
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35
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Almiron Bonnin DA, Havrda MC, Israel MA. Glioma Cell Secretion: A Driver of Tumor Progression and a Potential Therapeutic Target. Cancer Res 2018; 78:6031-6039. [PMID: 30333116 DOI: 10.1158/0008-5472.can-18-0345] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2018] [Revised: 05/30/2018] [Accepted: 08/14/2018] [Indexed: 11/16/2022]
Abstract
Cellular secretion is an important mediator of cancer progression. Secreted molecules in glioma are key components of complex autocrine and paracrine pathways that mediate multiple oncogenic pathologies. In this review, we describe tumor cell secretion in high-grade glioma and highlight potential novel therapeutic opportunities. Cancer Res; 78(21); 6031-9. ©2018 AACR.
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Affiliation(s)
- Damian A Almiron Bonnin
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire.,Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire
| | - Matthew C Havrda
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire.,Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire
| | - Mark A Israel
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire. .,Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire.,Departments of Medicine and Pediatrics, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire
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36
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Hainan L, Huilin L, Khan MA, Xin Z, YuJiang Y, Hui Z, Naiquan Y. The basic route of the nuclear translocation porcine growth hormone (GH)-growth hormone receptor (GHR) complex (pGH/GHR) in porcine hepatocytes. Gen Comp Endocrinol 2018; 266:101-109. [PMID: 29890130 DOI: 10.1016/j.ygcen.2018.05.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2017] [Revised: 04/04/2018] [Accepted: 05/06/2018] [Indexed: 11/19/2022]
Abstract
Traditional views suggest that growth hormone and the growth hormone receptor (GH/GHR complex) exert their functions only on the plasma membrane. This paradigm, however, has been challenged by recent new findings that the GH/GHR complex could translocate into cell nuclei where they could still exhibit important physiological functions. We also reported the nuclear localization of porcine GH/GHR and their potential functions in porcine hepatocytes. However, the basic path of pGH/GHR's nuclear translocation remains unclear. Combining previous research results and our current findings, we proposed two basic routes of pGH/GHR's nuclear transportation as follows: 1) after pGH binding to GHR, pGH/GHR enters into the cytoplasm though clathrin- or caveolin-mediated endocytosis, then the pGH/GHR complex enters into early endosomes (Rab5-positive), and the endosome carries the GH/GHR complex to the endoplasmic reticulum (ER). After endosome docking on the ER, the endosome starts fission, and the pGH/GHR complex enters into the ER lumen. Then the pGH/GHR complex transports into the cytoplasm, possibly by the ERAD pathway. Subsequently, the pGH/GHR complex interacts with IMPα/β, which, in turn, mediates GH/GHR nuclear localization; 2) pGH binds with the GHR on the cell membrane and, subsequently, pGH/GHR internalizes into the cell and enters into the endosome (this endosome may belong to a class of endosomes called envelope-associated endosomes (NAE)). Then, the endosome carries the pGH/GHR to the nuclear membrane. After docking on the nuclear membrane, the pGH/GHR complex fuses with the nuclear membrane and then enters into the cell nucleus.
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Affiliation(s)
- Lan Hainan
- College of Animal Science and Technology, Jilin Agricultural University, Changchun 130118, PR China.
| | - Liu Huilin
- College of Life Sciences, Jilin University, Changchun 130118, PR China
| | - Muhammad Akram Khan
- Department of Pathobiology, Faculty of Veterinary and Animal Sciences, PMAS-Arid Agriculture University, Rawalpindi, Pakistan
| | - Zheng Xin
- College of Animal Science and Technology, Jilin Agricultural University, Changchun 130118, PR China
| | - Yang YuJiang
- College of Animal Science and Technology, Jilin Agricultural University, Changchun 130118, PR China
| | - Zhang Hui
- College of Animal Science and Technology, Jilin Agricultural University, Changchun 130118, PR China
| | - Yao Naiquan
- College of Animal Science and Technology, Jilin Agricultural University, Changchun 130118, PR China
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37
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Demangel C, High S. Sec61 blockade by mycolactone: A central mechanism in Buruli ulcer disease. Biol Cell 2018; 110:237-248. [PMID: 30055020 DOI: 10.1111/boc.201800030] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Accepted: 07/19/2018] [Indexed: 12/14/2022]
Abstract
Infection with Mycobacterium ulcerans results in a necrotising skin disease known as a Buruli ulcer, the pathology of which is directly linked to the bacterial production of the toxin mycolactone. Recent studies have identified the protein translocation machinery of the endoplasmic reticulum (ER) membrane as the primary cellular target of mycolactone, and shown that the toxin binds to the core subunit of the Sec61 complex. Mycolactone binding strongly inhibits the capacity of the Sec61 translocon to transport newly synthesised membrane and secretory proteins into and across the ER membrane. Since the ER acts as the entry point for the mammalian secretory pathway, and hence regulates initial access to the entire endomembrane system, mycolactone-treated cells have a reduced ability to produce a range of proteins including secretory cytokines and plasma membrane receptors. The global effect of this molecular blockade of protein translocation at the ER is that the host is unable to mount an effective immune response to the underlying mycobacterial infection. Prolonged exposure to mycolactone is normally cytotoxic, since it triggers stress responses activating the transcription factor ATF4 and ultimately inducing apoptosis.
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Affiliation(s)
- Caroline Demangel
- Immunobiology of Infection Unit, Institut Pasteur, Paris, France.,INSERM, U1221, Paris, France
| | - Stephen High
- Division of Molecular and Cellular Function, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, M13 9PT, UK
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38
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Van Puyenbroeck V, Vermeire K. Inhibitors of protein translocation across membranes of the secretory pathway: novel antimicrobial and anticancer agents. Cell Mol Life Sci 2018; 75:1541-1558. [PMID: 29305616 PMCID: PMC5897483 DOI: 10.1007/s00018-017-2743-2] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2017] [Revised: 12/15/2017] [Accepted: 12/27/2017] [Indexed: 12/22/2022]
Abstract
Proteins routed to the secretory pathway start their journey by being transported across biological membranes, such as the endoplasmic reticulum. The essential nature of this protein translocation process has led to the evolution of several factors that specifically target the translocon and block translocation. In this review, various translocation pathways are discussed together with known inhibitors of translocation. Properties of signal peptide-specific systems are highlighted for the development of new therapeutic and antimicrobial applications, as compounds can target signal peptides from either host cells or pathogens and thereby selectively prevent translocation of those specific proteins. Broad inhibition of translocation is also an interesting target for the development of new anticancer drugs because cancer cells heavily depend on efficient protein translocation into the endoplasmic reticulum to support their fast growth.
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Affiliation(s)
- Victor Van Puyenbroeck
- Laboratory of Virology and Chemotherapy, Department of Microbiology and Immunology, Rega Institute for Medical Research, KU Leuven - University of Leuven, 3000, Leuven, Belgium
| | - Kurt Vermeire
- Laboratory of Virology and Chemotherapy, Department of Microbiology and Immunology, Rega Institute for Medical Research, KU Leuven - University of Leuven, 3000, Leuven, Belgium.
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39
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Figueiredo Costa B, Cassella P, Colombo SF, Borgese N. Discrimination between the endoplasmic reticulum and mitochondria by spontaneously inserting tail‐anchored proteins. Traffic 2018; 19:182-197. [DOI: 10.1111/tra.12550] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Revised: 01/18/2018] [Accepted: 01/18/2018] [Indexed: 01/16/2023]
Affiliation(s)
- Bruna Figueiredo Costa
- CNR Institute of Neuroscience and BIOMETRA DepartmentUniversità degli Studi di Milano Milan Italy
| | - Patrizia Cassella
- CNR Institute of Neuroscience and BIOMETRA DepartmentUniversità degli Studi di Milano Milan Italy
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40
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Abstract
The efficient production, folding, and secretion of proteins is critical for cancer cell survival. However, cancer cells thrive under stress conditions that damage proteins, so many cancer cells overexpress molecular chaperones that facilitate protein folding and target misfolded proteins for degradation via the ubiquitin-proteasome or autophagy pathway. Stress response pathway induction is also important for cancer cell survival. Indeed, validated targets for anti-cancer treatments include molecular chaperones, components of the unfolded protein response, the ubiquitin-proteasome system, and autophagy. We will focus on links between breast cancer and these processes, as well as the development of drug resistance, relapse, and treatment.
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Affiliation(s)
| | - Jeffrey L Brodsky
- Department of Biological Sciences, University of Pittsburgh, A320 Langley Hall, 4249 Fifth Ave, Pittsburgh, PA, 15260, USA.
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41
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Paatero AO, Kellosalo J, Dunyak BM, Almaliti J, Gestwicki JE, Gerwick WH, Taunton J, Paavilainen VO. Apratoxin Kills Cells by Direct Blockade of the Sec61 Protein Translocation Channel. Cell Chem Biol 2017; 23:561-566. [PMID: 27203376 DOI: 10.1016/j.chembiol.2016.04.008] [Citation(s) in RCA: 78] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2015] [Revised: 04/04/2016] [Accepted: 04/07/2016] [Indexed: 12/17/2022]
Abstract
Apratoxin A is a cytotoxic natural product that prevents the biogenesis of secretory and membrane proteins. Biochemically, apratoxin A inhibits cotranslational translocation into the ER, but its cellular target and mechanism of action have remained controversial. Here, we demonstrate that apratoxin A prevents protein translocation by directly targeting Sec61α, the central subunit of the protein translocation channel. Mutagenesis and competitive photo-crosslinking studies indicate that apratoxin A binds to the Sec61 lateral gate in a manner that differs from cotransin, a substrate-selective Sec61 inhibitor. In contrast to cotransin, apratoxin A does not exhibit a substrate-selective inhibitory mechanism, but blocks ER translocation of all tested Sec61 clients with similar potency. Our results suggest that multiple structurally unrelated natural products have evolved to target overlapping but non-identical binding sites on Sec61, thereby producing distinct biological outcomes.
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Affiliation(s)
- Anja O Paatero
- Institute of Biotechnology, University of Helsinki, Viikinkaari 1, Biocenter 3, Helsinki 00014, Finland
| | - Juho Kellosalo
- Institute of Biotechnology, University of Helsinki, Viikinkaari 1, Biocenter 3, Helsinki 00014, Finland
| | - Bryan M Dunyak
- Department of Pharmaceutical Chemistry, Institute for Neurodegenerative Disease, University of California at San Francisco, San Francisco, CA 94038, USA
| | - Jehad Almaliti
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California San Diego, La Jolla, CA 92093, USA
| | - Jason E Gestwicki
- Department of Pharmaceutical Chemistry, Institute for Neurodegenerative Disease, University of California at San Francisco, San Francisco, CA 94038, USA
| | - William H Gerwick
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California San Diego, La Jolla, CA 92093, USA
| | - Jack Taunton
- Department of Cellular and Molecular Pharmacology, Howard Hughes Medical Institute, University of California San Francisco, San Francisco, CA 94158, USA
| | - Ville O Paavilainen
- Institute of Biotechnology, University of Helsinki, Viikinkaari 1, Biocenter 3, Helsinki 00014, Finland.
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42
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Let's talk about Secs: Sec61, Sec62 and Sec63 in signal transduction, oncology and personalized medicine. Signal Transduct Target Ther 2017; 2:17002. [PMID: 29263911 PMCID: PMC5661625 DOI: 10.1038/sigtrans.2017.2] [Citation(s) in RCA: 91] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Revised: 01/11/2017] [Accepted: 01/17/2017] [Indexed: 12/11/2022] Open
Abstract
The heterotrimeric Sec61 complex and the dimeric Sec62/Sec63 complex are located in the membrane of the human endoplasmic reticulum (ER) and play a central role in translocation of nascent and newly synthesized precursor polypeptides into the ER. This process involves targeting of the precursors to the membrane and opening of the polypeptide conducting Sec61 channel for translocation. Apart from this central role in the intracellular transport of polypeptides, several studies of the last decade uncovered additional functions of Sec proteins in intracellular signaling: Sec62 can induce ER-phagy in the process of recovery of cells from ER stress and the Sec61 channel can also act as a passive ER calcium leak channel. Furthermore, mutations, amplifications and an overexpression of the SEC genes were linked to various diseases including kidney and liver diseases, diabetes and human cancer. Studies of the last decade could not only elucidate the functional role of Sec proteins in the pathogenesis of these diseases, but also demonstrate a relevance of Sec62 as a prognostic and predictive biomarker in head and neck cancer, prostate and lung cancer including a basis for new therapeutic strategies. In this article, we review the current understanding of protein transport across the ER membrane as central function of Sec proteins and further focus on recent studies that gave first insights into the functional role and therapeutic relevance of Sec61, Sec62 and Sec63 in human diseases.
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43
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McKenna M, Simmonds RE, High S. Mycolactone reveals the substrate-driven complexity of Sec61-dependent transmembrane protein biogenesis. J Cell Sci 2017; 130:1307-1320. [PMID: 28219954 PMCID: PMC5399781 DOI: 10.1242/jcs.198655] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2016] [Accepted: 02/02/2017] [Indexed: 12/22/2022] Open
Abstract
Mycolactone is the exotoxin virulence factor produced by Mycobacterium ulcerans, the pathogen responsible for Buruli ulcer. The skin lesions and immunosuppression that are characteristic of this disease result from the action of mycolactone, which targets the Sec61 complex and inhibits the co-translational translocation of secretory proteins into the endoplasmic reticulum. In this study, we investigate the effect of mycolactone on the Sec61-dependent biogenesis of different classes of transmembrane protein (TMP). Our data suggest that the effect of mycolactone on TMP biogenesis depends on how the nascent chain initially engages the Sec61 complex. For example, the translocation of TMP lumenal domains driven by an N-terminal cleavable signal sequence is efficiently inhibited by mycolactone. In contrast, the effect of mycolactone on protein translocation that is driven solely by a non-cleavable signal anchor/transmembrane domain depends on which flanking region is translocated. For example, while translocation of the region N-terminal to a signal anchor/transmembrane domain is refractive to mycolactone, C-terminal translocation is efficiently inhibited. Our findings highlight the diversity of Sec61-dependent translocation and provide a molecular basis for understanding the effect of mycolactone on the biogenesis of different TMPs. Highlighted Article: The exotoxin mycolactone interferes with the biogenesis of the majority of transmembrane proteins and its actions highlight differences in how distinct classes of these proteins initially engage the Sec61 translocon.
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Affiliation(s)
- Michael McKenna
- Division of Molecular and Cellular Function, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Michael Smith Building, Manchester M13 9PT, UK
| | - Rachel E Simmonds
- Department of Microbial Sciences, School of Bioscience and Medicine, Faculty of Health and Medical Sciences, University of Surrey, Guildford GU2 7XH, UK
| | - Stephen High
- Division of Molecular and Cellular Function, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Michael Smith Building, Manchester M13 9PT, UK
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44
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Wijeratne EMK, Gunaherath GMKB, Chapla VM, Tillotson J, de la Cruz F, Kang M, U'Ren JM, Araujo AR, Arnold AE, Chapman E, Gunatilaka AAL. Oxaspirol B with p97 Inhibitory Activity and Other Oxaspirols from Lecythophora sp. FL1375 and FL1031, Endolichenic Fungi Inhabiting Parmotrema tinctorum and Cladonia evansii. JOURNAL OF NATURAL PRODUCTS 2016; 79:340-52. [PMID: 26812276 PMCID: PMC4926610 DOI: 10.1021/acs.jnatprod.5b00986] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
A new metabolite, oxaspirol D (4), together with oxaspirols B (2) and C (3) were isolated from Lecythophora sp. FL1375, an endolichenic fungus isolated from Parmotrema tinctorum, whereas Lecythophora sp. FL1031 inhabiting the lichen Cladonia evansii afforded oxaspirols A (1), B (2), and C (3). Of these, oxaspirol B (2) showed moderate p97 ATPase inhibitory activity. A detailed characterization of all oxaspirols was undertaken because structures proposed for known oxaspirols have involved incomplete assignments of NMR spectroscopic data leading only to their planar structures. Thus, the naturally occurring isomeric mixture (2a and 2b) of oxaspirol B was separated as their diacetates (5a and 5b) and the structures and absolute configurations of 1, 2a, 2b, 3, and 4 were determined by the application of spectroscopic techniques including two-dimensional NMR and the modified Mosher's ester method. Oxaspirol B (2) and its diacetates 5a and 5b were evaluated for their ATPase inhibitory activities of p97, p97 mutants, and other ATP-utilizing enzymes, and only 2 was found to be active, indicating the requirement of some structural features in oxaspirols for their activity. Additional biochemical and cellular assays suggested that 2 was a reversible, non-ATP competitive, and specific inhibitor of p97.
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Affiliation(s)
- E. M. Kithsiri Wijeratne
- Natural Products Center, School of Natural Resources and the Environment, College of Agriculture and Life Sciences, University of Arizona, 250 East Valencia Road, Tucson, Arizona 85706, United States
| | - G. M. Kamal B. Gunaherath
- Natural Products Center, School of Natural Resources and the Environment, College of Agriculture and Life Sciences, University of Arizona, 250 East Valencia Road, Tucson, Arizona 85706, United States
- Department of Chemistry, Open University of Sri Lanka, Nugegoda 10250, Sri Lanka
| | - Vanessa M. Chapla
- Natural Products Center, School of Natural Resources and the Environment, College of Agriculture and Life Sciences, University of Arizona, 250 East Valencia Road, Tucson, Arizona 85706, United States
- Departamento de Química Orgânica, Instituto de Química, UNESP, Universidade Estadual Paulista, Araraquara, Sao Paulo 14800-900, Brazil
| | - Joseph Tillotson
- Department of Pharmacology and Toxicology, College of Pharmacy, University of Arizona, Tucson, Arizona 85721, United States
| | - Fabian de la Cruz
- Department of Pharmacology and Toxicology, College of Pharmacy, University of Arizona, Tucson, Arizona 85721, United States
| | - MinJing Kang
- Department of Pharmacology and Toxicology, College of Pharmacy, University of Arizona, Tucson, Arizona 85721, United States
| | - Jana M. U'Ren
- School of Plant Sciences, College of Agriculture and Life Sciences, University of Arizona, Tucson, Arizona 85721, United States
| | - Angela R. Araujo
- Departamento de Química Orgânica, Instituto de Química, UNESP, Universidade Estadual Paulista, Araraquara, Sao Paulo 14800-900, Brazil
| | - A. Elizabeth Arnold
- School of Plant Sciences, College of Agriculture and Life Sciences, University of Arizona, Tucson, Arizona 85721, United States
- Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, Arizona 85721, United States
| | - Eli Chapman
- Department of Pharmacology and Toxicology, College of Pharmacy, University of Arizona, Tucson, Arizona 85721, United States
| | - A. A. Leslie Gunatilaka
- Natural Products Center, School of Natural Resources and the Environment, College of Agriculture and Life Sciences, University of Arizona, 250 East Valencia Road, Tucson, Arizona 85706, United States
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45
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McKenna M, Simmonds RE, High S. Mechanistic insights into the inhibition of Sec61-dependent co- and post-translational translocation by mycolactone. J Cell Sci 2016; 129:1404-15. [PMID: 26869228 PMCID: PMC4852723 DOI: 10.1242/jcs.182352] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2015] [Accepted: 02/03/2016] [Indexed: 12/17/2022] Open
Abstract
The virulence factor mycolactone is responsible for the immunosuppression and tissue necrosis that characterise Buruli ulcer, a disease caused by infection with Mycobacterium ulcerans In this study, we confirm that Sec61, the protein-conducting channel that coordinates entry of secretory proteins into the endoplasmic reticulum, is a primary target of mycolactone, and characterise the nature of its inhibitory effect. We conclude that mycolactone constrains the ribosome-nascent-chain-Sec61 complex, consistent with its broad-ranging perturbation of the co-translational translocation of classical secretory proteins. In contrast, the effect of mycolactone on the post-translational ribosome-independent translocation of short secretory proteins through the Sec61 complex is dependent on both signal sequence hydrophobicity and the translocation competence of the mature domain. Changes to protease sensitivity strongly suggest that mycolactone acts by inducing a conformational change in the pore-forming Sec61α subunit. These findings establish that mycolactone inhibits Sec61-mediated protein translocation and highlight differences between the co- and post-translational routes that the Sec61 complex mediates. We propose that mycolactone also provides a useful tool for further delineating the molecular mechanisms of Sec61-dependent protein translocation.
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Affiliation(s)
- Michael McKenna
- Faculty of Life Sciences, University of Manchester, Michael Smith Building, Manchester M13 9PT, UK
| | - Rachel E Simmonds
- Department of Microbial Sciences, School of Bioscience and Medicine, Faculty of Health and Medical Sciences, University of Surrey, Guildford GU2 7XH, UK
| | - Stephen High
- Faculty of Life Sciences, University of Manchester, Michael Smith Building, Manchester M13 9PT, UK
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46
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Berry GE, Asokan A. Chemical Modulation of Endocytic Sorting Augments Adeno-associated Viral Transduction. J Biol Chem 2016; 291:939-47. [PMID: 26527686 PMCID: PMC4705411 DOI: 10.1074/jbc.m115.687657] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Revised: 10/24/2015] [Indexed: 01/10/2023] Open
Abstract
Intracellular trafficking of viruses can be influenced by a variety of inter-connected cellular sorting and degradation pathways involving endo-lysosomal vesicles, the ubiquitin-proteasome system, and autophagy-based or endoplasmic reticulum-associated machinery. In the case of recombinant adeno-associated viruses (AAV), proteasome inhibitors are known to prevent degradation of ubiquitinated AAV capsids, thereby leading to increased nuclear accumulation and transduction. However, the impact of other cellular degradation pathways on AAV trafficking is not well understood. In the current study, we screened a panel of small molecules focused on modulating different cellular degradation pathways and identified eeyarestatin I (EerI) as a novel reagent that enhances AAV transduction. EerI improved AAV transduction by an order of magnitude regardless of vector dose, genome architecture, cell type, or serotype. This effect was preceded by sequestration of AAV within enlarged vesicles that were dispersed throughout the cytoplasm. Specifically, EerI treatment redirected AAV particles toward large vesicles positive for late endosomal (Rab7) and lysosomal (LAMP1) markers. Notably, MG132 and EerI (proteasomal and endoplasmic reticulum-associated degradation inhibitors, respectively) appear to enhance AAV transduction by increasing the intracellular accumulation of viral particles in a mutually exclusive fashion. Taken together, our results expand on potential strategies to redirect recombinant AAV vectors toward more productive trafficking pathways by deregulating cellular degradation mechanisms.
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Affiliation(s)
- Garrett E Berry
- From the Gene Therapy Center, Department of Genetics, Curriculum in Genetics and Molecular Biology, and
| | - Aravind Asokan
- From the Gene Therapy Center, Department of Genetics, Department of Biochemistry and Biophysics, The University of North Carolina, Chapel Hill, North Carolina 27599-7352
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47
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Cancer Microenvironment and Endoplasmic Reticulum Stress Response. Mediators Inflamm 2015; 2015:417281. [PMID: 26491226 PMCID: PMC4600498 DOI: 10.1155/2015/417281] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Revised: 04/21/2015] [Accepted: 04/24/2015] [Indexed: 12/17/2022] Open
Abstract
Different stressful conditions such as hypoxia, nutrient deprivation, pH changes, or reduced vascularization, potentially able to act as growth-limiting factors for tumor cells, activate the unfolded protein response (UPR). UPR is therefore involved in tumor growth and adaptation to severe environments and is generally cytoprotective in cancer. The present review describes the molecular mechanisms underlying UPR and able to promote survival and proliferation in cancer. The critical role of UPR activation in tumor growth promotion is discussed in detail for a few paradigmatic tumors such as prostate cancer and melanoma.
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48
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Translation in the mammalian oocyte in space and time. Cell Tissue Res 2015; 363:69-84. [PMID: 26340983 DOI: 10.1007/s00441-015-2269-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Accepted: 08/03/2015] [Indexed: 02/07/2023]
Abstract
A hallmark of oocyte development in mammals is the dependence on the translation and utilization of stored RNA and proteins rather than the de novo transcription of genes in order to sustain meiotic progression and early embryo development. In the absence of transcription, the completion of meiosis and early embryo development in mammals relies significantly on maternally synthesized RNAs. Post-transcriptional control of gene expression at the translational level has emerged as an important cellular function in normal development. Therefore, the regulation of gene expression in oocytes is controlled almost exclusively at the level of mRNA and protein stabilization and protein synthesis. This current review is focused on the recently emerged findings on RNA distribution related to the temporal and spatial translational control of the meiotic progression of the mammalian oocyte.
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49
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Kalies KU, Römisch K. Inhibitors of Protein Translocation Across the ER Membrane. Traffic 2015; 16:1027-38. [PMID: 26122014 DOI: 10.1111/tra.12308] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2015] [Revised: 06/18/2015] [Accepted: 06/22/2015] [Indexed: 12/21/2022]
Abstract
Protein translocation into the endoplasmic reticulum (ER) constitutes the first step of protein secretion. ER protein import is essential in all eukaryotic cells and is particularly critical in fast-growing tumour cells. Thus, the process can serve as target both for potential cancer drugs and for bacterial virulence factors. Inhibitors of protein transport across the ER membrane range from broad-spectrum to highly substrate-specific and can interfere with virtually any stage of this multistep process, and even with transport of endocytosed antigens into the cytosol for cross-presentation.
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Affiliation(s)
- Kai-Uwe Kalies
- Institute of Biology, CSCM, University of Lübeck, Lübeck, Germany
| | - Karin Römisch
- Department of Microbiology, Faculty of Natural Sciences and Technology VIII, Saarland University, 66123, Saarbrücken, Germany
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Meinig JM, Fu L, Peterson BR. Synthesis of Fluorophores that Target Small Molecules to the Endoplasmic Reticulum of Living Mammalian Cells. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201504156] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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