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Knupp J, Chen YJ, Wang E, Arvan P, Tsai B. Sigma-1 receptor recruits LC3 mRNA to ER-associated omegasomes to promote localized LC3 translation enabling functional autophagy. Cell Rep 2024; 43:114619. [PMID: 39128005 PMCID: PMC11376464 DOI: 10.1016/j.celrep.2024.114619] [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: 01/16/2024] [Revised: 05/14/2024] [Accepted: 07/25/2024] [Indexed: 08/13/2024] Open
Abstract
Autophagosome formation initiated on the endoplasmic reticulum (ER)-associated omegasome requires LC3. Translational regulation of LC3 biosynthesis is unexplored. Here we demonstrate that LC3 mRNA is recruited to omegasomes by directly binding to the ER transmembrane Sigma-1 receptor (S1R). Cell-based and in vitro reconstitution experiments show that S1R interacts with the 3' UTR of LC3 mRNA and ribosomes to promote LC3 translation. Strikingly, the 3' UTR of LC3 is also required for LC3 protein lipidation, thereby linking the mRNA-3' UTR to LC3 function. An autophagy-defective S1R mutant responsible for amyotrophic lateral sclerosis cannot bind LC3 mRNA or induce LC3 translation. We propose a model wherein S1R de-represses LC3 mRNA via its 3' UTR at the ER, enabling LC3 biosynthesis and lipidation. Because several other LC3-related proteins use the same mechanism, our data reveal a conserved pathway for localized translation essential for autophagosome biogenesis with insights illuminating the molecular basis of a neurodegenerative disease.
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Affiliation(s)
- Jeffrey Knupp
- Department of Cell & Developmental Biology, University of Michigan Medical School, 109 Zina Pitcher Place, BSRB 3043, Ann Arbor, MI 48109, USA; Cellular and Molecular Biology Program, University of Michigan Medical School, 1135 Catherine Street, Ann Arbor, MI 48109 USA
| | - Yu-Jie Chen
- Department of Cell & Developmental Biology, University of Michigan Medical School, 109 Zina Pitcher Place, BSRB 3043, Ann Arbor, MI 48109, USA
| | - Emily Wang
- Department of Cell & Developmental Biology, University of Michigan Medical School, 109 Zina Pitcher Place, BSRB 3043, Ann Arbor, MI 48109, USA
| | - Peter Arvan
- Cellular and Molecular Biology Program, University of Michigan Medical School, 1135 Catherine Street, Ann Arbor, MI 48109 USA; Division of Metabolism Endocrinology & Diabetes, University of Michigan Medical School, 1000 Wall Street, Ann Arbor, MI 48105, USA.
| | - Billy Tsai
- Department of Cell & Developmental Biology, University of Michigan Medical School, 109 Zina Pitcher Place, BSRB 3043, Ann Arbor, MI 48109, USA; Cellular and Molecular Biology Program, University of Michigan Medical School, 1135 Catherine Street, Ann Arbor, MI 48109 USA.
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2
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Zou Y, Zhang X, Chen XY, Ma XF, Feng XY, Sun Y, Ma T, Ma QH, Zhao XD, Xu DE. Contactin -Associated protein1 Regulates Autophagy by Modulating the PI3K/AKT/mTOR Signaling Pathway and ATG4B Levels in Vitro and in Vivo. Mol Neurobiol 2024:10.1007/s12035-024-04425-9. [PMID: 39164481 DOI: 10.1007/s12035-024-04425-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2024] [Accepted: 08/06/2024] [Indexed: 08/22/2024]
Abstract
Contactin-associated protein1 (Caspr1) plays an important role in the formation and stability of myelinated axons. In Caspr1 mutant mice, autophagy-related structures accumulate in neurons, causing axonal degeneration; however, the mechanism by which Caspr1 regulates autophagy remains unknown. To illustrate the mechanism of Caspr1 in autophagy process, we demonstrated that Caspr1 knockout in primary neurons from mice along with human cell lines, HEK-293 and HeLa, induced autophagy by downregulating the PI3K/AKT/mTOR signaling pathway to promote the conversion of microtubule-associated protein light chain 3 I (LC3-I) to LC3-II. In contrast, Caspr1 overexpression in cells contributed to the upregulation of this signaling pathway. We also demonstrated that Caspr1 knockout led to increased LC3-I protein expression in mice. In addition, Caspr1 could inhibit the expression of autophagy-related 4B cysteine peptidase (ATG4B) protein by directly binding to ATG4B in overexpressed Caspr1 cells. Intriguingly, we found an accumulation of ATG4B in the Golgi apparatuses of cells overexpressing Caspr1; therefore, we speculate that Caspr1 may restrict ATG4 secretion from the Golgi apparatus to the cytoplasm. Collectively, our results indicate that Caspr1 may regulate autophagy by modulating the PI3K/AKT/mTOR signaling pathway and the levels of ATG4 protein, both in vitro and in vivo. Thus, Caspr1 can be a potential therapeutic target in axonal damage and demyelinating diseases.
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Affiliation(s)
- Yan Zou
- Department of Neurosurgery, Jiangnan University Medical Center, the Wuxi No.2 People Hospital, Wuxi, 214002, Jiangsu, China
| | - Xiao Zhang
- Wuxi School of Medicine, Jiangnan University, Wuxi, 214002, Jiangsu, China
- Department of Neurology, Jiangnan University Medical Center, the Wuxi No.2 People Hospital, Wuxi, 214002, Jiangsu, China
| | - Xin-Yi Chen
- Department of Neurology, Jiangnan University Medical Center, the Wuxi No.2 People Hospital, Wuxi, 214002, Jiangsu, China
| | - Xiao-Fang Ma
- Hong Shan Hospital, Wuxi, 214000, Jiangsu, China
| | - Xiao-Yan Feng
- Department of Neurology, Jiangnan University Medical Center, the Wuxi No.2 People Hospital, Wuxi, 214002, Jiangsu, China
| | - Yang Sun
- Department of Neurology, Jiangnan University Medical Center, the Wuxi No.2 People Hospital, Wuxi, 214002, Jiangsu, China
| | - Tao Ma
- Department of Neurology, Jiangnan University Medical Center, the Wuxi No.2 People Hospital, Wuxi, 214002, Jiangsu, China
| | - Quan-Hong Ma
- Jiangsu Key Laboratory of Neuropsychiatric Diseases, Institute of Neuroscience, Soochow University, Suzhou, 215004, Jiangsu, China
| | - Xu-Dong Zhao
- Department of Neurosurgery, Jiangnan University Medical Center, the Wuxi No.2 People Hospital, Wuxi, 214002, Jiangsu, China.
- Wuxi Neurosurgical Institute, Wuxi, 214122, Jiangsu, China.
| | - De-En Xu
- Wuxi School of Medicine, Jiangnan University, Wuxi, 214002, Jiangsu, China.
- Department of Neurology, Jiangnan University Medical Center, the Wuxi No.2 People Hospital, Wuxi, 214002, Jiangsu, China.
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3
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Figueras-Novoa C, Timimi L, Marcassa E, Ulferts R, Beale R. Conjugation of ATG8s to single membranes at a glance. J Cell Sci 2024; 137:jcs261031. [PMID: 39145464 PMCID: PMC11361636 DOI: 10.1242/jcs.261031] [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] [Indexed: 08/16/2024] Open
Abstract
Autophagy refers to a set of degradative mechanisms whereby cytoplasmic contents are targeted to the lysosome. This is best described for macroautophagy, where a double-membrane compartment (autophagosome) is generated to engulf cytoplasmic contents. Autophagosomes are decorated with ubiquitin-like ATG8 molecules (ATG8s), which are recruited through covalent lipidation, catalysed by the E3-ligase-like ATG16L1 complex. LC3 proteins are ATG8 family members that are often used as a marker for autophagosomes. In contrast to canonical macroautophagy, conjugation of ATG8s to single membranes (CASM) describes a group of non-canonical autophagy processes in which ATG8s are targeted to pre-existing single-membrane compartments. CASM occurs in response to disrupted intracellular pH gradients, when the V-ATPase proton pump recruits ATG16L1 in a process called V-ATPase-ATG16L1-induced LC3 lipidation (VAIL). Recent work has demonstrated a parallel, alternative axis for CASM induction, triggered when the membrane recruitment factor TECPR1 recognises sphingomyelin exposed on the cytosolic face of a membrane and forms an alternative E3-ligase-like complex. This sphingomyelin-TECPR1-induced LC3 lipidation (STIL) is independent of the V-ATPase and ATG16L1. In light of these discoveries, this Cell Science at a Glance article summarises these two mechanisms of CASM to highlight how they differ from canonical macroautophagy, and from each other.
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Affiliation(s)
- Carmen Figueras-Novoa
- Cell Biology of Infection Laboratory, The Francis Crick Institute, London NW1 1AT, UK
| | - Lewis Timimi
- Cell Biology of Infection Laboratory, The Francis Crick Institute, London NW1 1AT, UK
- Division of Medicine, University College London, London NW1 1AT, UK
| | - Elena Marcassa
- Cell Biology of Infection Laboratory, The Francis Crick Institute, London NW1 1AT, UK
| | - Rachel Ulferts
- Cell Biology of Infection Laboratory, The Francis Crick Institute, London NW1 1AT, UK
| | - Rupert Beale
- Cell Biology of Infection Laboratory, The Francis Crick Institute, London NW1 1AT, UK
- Division of Medicine, University College London, London NW1 1AT, UK
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4
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Feng Q, Sun L, Sualeh MJ, Zhao Q, Zhao S, Cui Z, Inadera H. Hernandezine promotes cancer cell apoptosis and disrupts the lysosomal acidic environment and cathepsin D maturation. Chin J Nat Med 2024; 22:387-401. [PMID: 38796213 DOI: 10.1016/s1875-5364(24)60638-2] [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: 11/23/2023] [Indexed: 05/28/2024]
Abstract
Hernandezine (Her), a bisbenzylisoquinoline alkaloid extracted from Thalictrum flavum, is recognized for its range of biological activities inherent to this herbal medicine. Despite its notable properties, the anti-cancer effects of Her have remained largely unexplored. In this study, we elucidated that Her significantly induced cytotoxicity in cancer cells through the activation of apoptosis and necroptosis mechanisms. Furthermore, Her triggered autophagosome formation by activating the AMPK and ATG5 conjugation systems, leading to LC3 lipidation. Our findings revealed that Her caused damage to the mitochondrial membrane, with the damaged mitochondria undergoing mitophagy, as evidenced by the elevated expression of mitophagy markers. Conversely, Her disrupted autophagic flux, demonstrated by the upregulation of p62 and accumulation of autolysosomes, as observed in the RFP-GFP-LC3 reporter assay. Initially, we determined that Her did not prevent the fusion of autophagosomes and lysosomes. However, it inhibited the maturation of cathepsin D and increased lysosomal pH, indicating an impairment of lysosomal function. The use of the early-stage autophagy inhibitor, 3-methyladenine (3-MA), did not suppress LC3II, suggesting that Her also induces noncanonical autophagy in autophagosome formation. The application of Bafilomycin A1, an inhibitor of noncanonical autophagy, diminished the recruitment of ATG16L1 and the accumulation of LC3II by Her, thereby augmenting Her-induced cell death. These observations imply that while autophagy initially plays a protective role, the disruption of the autophagic process by Her promotes programmed cell death. This study provides the first evidence of Her's dual role in inducing apoptosis and necroptosis while also initiating and subsequently impairing autophagy to promote apoptotic cell death. These insights contribute to a deeper understanding of the mechanisms underlying programmed cell death, offering potential avenues for enhancing cancer prevention and therapeutic strategies.
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Affiliation(s)
- Qianwen Feng
- Department of Public Health, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama 930-8501, Japan
| | - Lu Sun
- Department of Pediatric Cardiology, Heart Center, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou 510000, China
| | - Muhammad Jibran Sualeh
- Department of Basic Medical Sciences, College of Medicine, University of Sharjah, Sharjah 57545, United Arab Emirates
| | - Qingli Zhao
- Department of Radiology, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama 930-8501, Japan
| | - Songji Zhao
- Advanced Clinical Research Center, Fukushima Global Medical Science Center, Fukushima Medical University, Fukushima City, Fukushima 960-8074, Japan
| | - Zhengguo Cui
- Department of Environmental Health, School of Medical Sciences, University of Fukui, Fukui 910-8580, Japan.
| | - Hidekuni Inadera
- Department of Public Health, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama 930-8501, Japan.
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5
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Tang J, Fang D, Zhong J, Li M. Missing WD40 Repeats in ATG16L1 Delays Canonical Autophagy and Inhibits Noncanonical Autophagy. Int J Mol Sci 2024; 25:4493. [PMID: 38674078 PMCID: PMC11050548 DOI: 10.3390/ijms25084493] [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: 03/13/2024] [Revised: 04/13/2024] [Accepted: 04/17/2024] [Indexed: 04/28/2024] Open
Abstract
Canonical autophagy is an evolutionarily conserved process that forms double-membrane structures and mediates the degradation of long-lived proteins (LLPs). Noncanonical autophagy (NCA) is an important alternative pathway involving the formation of microtubule-associated protein 1 light chain 3 (LC3)-positive structures that are independent of partial core autophagy proteins. NCA has been defined by the conjugation of ATG8s to single membranes (CASM). During canonical autophagy and NCA/CASM, LC3 undergoes a lipidation modification, and ATG16L1 is a crucial protein in this process. Previous studies have reported that the WDR domain of ATG16L1 is not necessary for canonical autophagy. However, our study found that WDR domain deficiency significantly impaired LLP degradation in basal conditions and slowed down LC3-II accumulation in canonical autophagy. We further demonstrated that the observed effect was due to a reduced interaction between ATG16L1 and FIP200/WIPI2, without affecting lysosome function or fusion. Furthermore, we also found that the WDR domain of ATG16L1 is crucial for chemical-induced NCA/CASM. The results showed that removing the WDR domain or introducing the K490A mutation in ATG16L1 significantly inhibited the NCA/CASM, which interrupted the V-ATPase-ATG16L1 axis. In conclusion, this study highlights the significance of the WDR domain of ATG16L1 for both canonical autophagy and NCA functions, improving our understanding of its role in autophagy.
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Affiliation(s)
- Jiuge Tang
- State Key Laboratory of Anti-Infective Drug Discovery and Development, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China
- Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, Guangzhou 510006, China
| | - Dongmei Fang
- State Key Laboratory of Anti-Infective Drug Discovery and Development, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China
- Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, Guangzhou 510006, China
| | - Jialing Zhong
- State Key Laboratory of Anti-Infective Drug Discovery and Development, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China
- Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, Guangzhou 510006, China
| | - Min Li
- State Key Laboratory of Anti-Infective Drug Discovery and Development, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China
- Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, Guangzhou 510006, China
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Gao C, Shi Q, Pan X, Chen J, Zhang Y, Lang J, Wen S, Liu X, Cheng TL, Lei K. Neuromuscular organoids model spinal neuromuscular pathologies in C9orf72 amyotrophic lateral sclerosis. Cell Rep 2024; 43:113892. [PMID: 38431841 DOI: 10.1016/j.celrep.2024.113892] [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: 06/28/2023] [Revised: 12/04/2023] [Accepted: 02/15/2024] [Indexed: 03/05/2024] Open
Abstract
Hexanucleotide repeat expansions in the C9orf72 gene are the most common cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia. Due to the lack of trunk neuromuscular organoids (NMOs) from ALS patients' induced pluripotent stem cells (iPSCs), an organoid system was missing to model the trunk spinal neuromuscular neurodegeneration. With the C9orf72 ALS patient-derived iPSCs and isogenic controls, we used an NMO system containing trunk spinal cord neural and peripheral muscular tissues to show that the ALS NMOs could model peripheral defects in ALS, including contraction weakness, neural denervation, and loss of Schwann cells. The neurons and astrocytes in ALS NMOs manifested the RNA foci and dipeptide repeat proteins. Acute treatment with the unfolded protein response inhibitor GSK2606414 increased the glutamatergic muscular contraction 2-fold and reduced the dipeptide repeat protein aggregation and autophagy. This study provides an organoid system for spinal neuromuscular pathologies in ALS and its application for drug testing.
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Affiliation(s)
- Chong Gao
- Westlake Laboratory of Life Sciences and Biomedicine, Key Laboratory of Growth Regulation and Translational Research of Zhejiang Province, School of Life Sciences, Westlake University, Hangzhou, Zhejiang, China; Institute of Biology, Westlake Institute for Advanced Study, Hangzhou, Zhejiang, China; Key Laboratory of Novel Targets and Drug Study for Neural Repair of Zhejiang Province, Institute of Brain and Cognitive Science, School of Medicine, Hangzhou City University, Hangzhou, Zhejiang, China
| | - Qinghua Shi
- Westlake Laboratory of Life Sciences and Biomedicine, Key Laboratory of Growth Regulation and Translational Research of Zhejiang Province, School of Life Sciences, Westlake University, Hangzhou, Zhejiang, China; Institute of Biology, Westlake Institute for Advanced Study, Hangzhou, Zhejiang, China; Fudan University, Shanghai, China
| | - Xue Pan
- Westlake Laboratory of Life Sciences and Biomedicine, Key Laboratory of Growth Regulation and Translational Research of Zhejiang Province, School of Life Sciences, Westlake University, Hangzhou, Zhejiang, China; Institute of Biology, Westlake Institute for Advanced Study, Hangzhou, Zhejiang, China; College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang, China
| | - Jiajia Chen
- Westlake Laboratory of Life Sciences and Biomedicine, Key Laboratory of Growth Regulation and Translational Research of Zhejiang Province, School of Life Sciences, Westlake University, Hangzhou, Zhejiang, China; Institute of Biology, Westlake Institute for Advanced Study, Hangzhou, Zhejiang, China
| | - Yuhong Zhang
- Westlake Laboratory of Life Sciences and Biomedicine, Key Laboratory of Growth Regulation and Translational Research of Zhejiang Province, School of Life Sciences, Westlake University, Hangzhou, Zhejiang, China; Institute of Biology, Westlake Institute for Advanced Study, Hangzhou, Zhejiang, China
| | - Jiali Lang
- Westlake Laboratory of Life Sciences and Biomedicine, Key Laboratory of Growth Regulation and Translational Research of Zhejiang Province, School of Life Sciences, Westlake University, Hangzhou, Zhejiang, China; Institute of Biology, Westlake Institute for Advanced Study, Hangzhou, Zhejiang, China
| | - Shan Wen
- Westlake Laboratory of Life Sciences and Biomedicine, Key Laboratory of Growth Regulation and Translational Research of Zhejiang Province, School of Life Sciences, Westlake University, Hangzhou, Zhejiang, China; Institute of Biology, Westlake Institute for Advanced Study, Hangzhou, Zhejiang, China; Research Center for Industries of the Future, Westlake University, Hangzhou, Zhejiang, China
| | - Xiaodong Liu
- Westlake Laboratory of Life Sciences and Biomedicine, Key Laboratory of Growth Regulation and Translational Research of Zhejiang Province, School of Life Sciences, Westlake University, Hangzhou, Zhejiang, China; Institute of Biology, Westlake Institute for Advanced Study, Hangzhou, Zhejiang, China; Research Center for Industries of the Future, Westlake University, Hangzhou, Zhejiang, China
| | - Tian-Lin Cheng
- Institute for Translational Brain Research, State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, Institute of Pediatrics, National Children's Medical Center, Children's Hospital, Fudan University, Shanghai, China
| | - Kai Lei
- Westlake Laboratory of Life Sciences and Biomedicine, Key Laboratory of Growth Regulation and Translational Research of Zhejiang Province, School of Life Sciences, Westlake University, Hangzhou, Zhejiang, China; Institute of Biology, Westlake Institute for Advanced Study, Hangzhou, Zhejiang, China.
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7
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Zhai H, Wang T, Liu D, Pan L, Sun Y, Qiu HJ. Autophagy as a dual-faced host response to viral infections. Front Cell Infect Microbiol 2023; 13:1289170. [PMID: 38125906 PMCID: PMC10731275 DOI: 10.3389/fcimb.2023.1289170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Accepted: 11/10/2023] [Indexed: 12/23/2023] Open
Abstract
Autophagy selectively degrades viral particles or cellular components, either facilitating or inhibiting viral replication. Conversely, most viruses have evolved strategies to escape or exploit autophagy. Moreover, autophagy collaborates with the pattern recognition receptor signaling, influencing the expression of adaptor molecules involved in the innate immune response and regulating the expression of interferons (IFNs). The intricate relationship between autophagy and IFNs plays a critical role in the host cell defense against microbial invasion. Therefore, it is important to summarize the interactions between viral infections, autophagy, and the host defense mechanisms against viruses. This review specifically focuses on the interactions between autophagy and IFN pathways during viral infections, providing a comprehensive summary of the molecular mechanisms utilized or evaded by different viruses.
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Affiliation(s)
| | | | | | | | - Yuan Sun
- State Key Laboratory for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | - Hua-Ji Qiu
- State Key Laboratory for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
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8
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Zheng Z, Zhao M, Shan H, Fang D, Jin Z, Tang J, Liu Z, Hong L, Liu P, Li M. Noncanonical autophagy is a new strategy to inhibit HSV-1 through STING1 activation. Autophagy 2023; 19:3096-3112. [PMID: 37471002 PMCID: PMC10621258 DOI: 10.1080/15548627.2023.2237794] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Revised: 07/06/2023] [Accepted: 07/13/2023] [Indexed: 07/21/2023] Open
Abstract
STING1 (stimulator of interferon response cGAMP interactor 1) plays an essential role in immune responses for virus inhibition via inducing the production of type I interferon, inflammatory factors and macroautophagy/autophagy. In this study, we found that STING1 activation could induce not only canonical autophagy but also non-canonical autophagy (NCA) which is independent of the ULK1 or BECN1 complexes to form MAP1LC3/LC3-positive structures. Whether STING1-induced NCA has similar characters and physiological functions to canonical autophagy is totally unknown. Different from canonical autophagy, NCA could increase single-membrane structures and failed to degrade long-lived proteins, and could be strongly suppressed by interrupting vacuolar-type H+-translocating ATPase (V-ATPase) activity. Importantly, STING1-induced NCA could effectively inhibit DNA virus HSV-1 in cell model. Moreover, STING1 [1-340], a STING1 mutant lacking immunity and inflammatory response due to deletion of the tail end of STING1, could degrade virus through NCA alone, suggesting that the antiviral effect of activated STING1 could be separately mediated by inherent immunity, canonical autophagy, and NCA. In addition, the translocation and dimerization of STING1 do not rely on its immunity function and autophagy pathway. Similar to canonical autophagy, LC3-positive structures of NCA induced by STING1 could finally fuse with lysosomes, and the degradation of HSV-1 could be reverted by inhibition of lysosome function, suggesting that the elimination of DNA virus via NCA still requires the lysosome pathway. Collectively, we proved that besides its classical immunity function and canonical autophagy pathway, STING1-induced NCA is also an efficient antiviral pathway for the host cell.Abbreviations: ATG: autophagy related; Baf: bafilomycin A1; CASM: conjugation of LC3 to a single membrane; CGAS: cyclic GMP-AMP synthase; cGAMP: cyclic GMP-AMP; CQ: chloroquine; CTD: C-terminal domain; CTT: C-terminal tail; ER: endoplasmic reticulum; ERGIC: ER-Golgi intermediate compartment; HSV-1: herpes simplex virus 1; IRF3: interferon regulatory factor 3; IFNs: interferons; LAMP1: lysosomal associated membrane protein 1; LAP: LC3-associated phagocytosis; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; MOI: multiplicity of infection; RB1CC1/FIP200: RB1 inducible coiled-coil 1; STING1: stimulator of interferon response cGAMP interactor 1; TBK1: TANK binding kinase 1; TGOLN2/TGN46: trans-golgi network protein 2; ULK1: unc-51 like autophagy activating kinase 1; V-ATPase: vacuolar-type H+-translocating ATPase; VSV: vesicular stomatitis virus.
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Affiliation(s)
- Zhihua Zheng
- School of Pharmaceutical Sciences, Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, National and Local Joint Engineering Laboratory of Druggability and New Drugs Evaluation, Sun Yat-Sen University, Guangzhou, Guangdong, China
- School of Pharmaceutical Sciences, Jinan University, Guangzhou, Guangdong, China
| | - Man Zhao
- School of Pharmaceutical Sciences, Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, National and Local Joint Engineering Laboratory of Druggability and New Drugs Evaluation, Sun Yat-Sen University, Guangzhou, Guangdong, China
| | - Hao Shan
- School of Pharmaceutical Sciences, Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, National and Local Joint Engineering Laboratory of Druggability and New Drugs Evaluation, Sun Yat-Sen University, Guangzhou, Guangdong, China
| | - Dongmei Fang
- School of Pharmaceutical Sciences, Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, National and Local Joint Engineering Laboratory of Druggability and New Drugs Evaluation, Sun Yat-Sen University, Guangzhou, Guangdong, China
| | - Zuyi Jin
- School of Pharmaceutical Sciences, Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, National and Local Joint Engineering Laboratory of Druggability and New Drugs Evaluation, Sun Yat-Sen University, Guangzhou, Guangdong, China
| | - Jiuge Tang
- School of Pharmaceutical Sciences, Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, National and Local Joint Engineering Laboratory of Druggability and New Drugs Evaluation, Sun Yat-Sen University, Guangzhou, Guangdong, China
| | - Zhiping Liu
- School of Pharmaceutical Sciences, Jinan University, Guangzhou, Guangdong, China
| | - Liang Hong
- School of Pharmaceutical Sciences, Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, National and Local Joint Engineering Laboratory of Druggability and New Drugs Evaluation, Sun Yat-Sen University, Guangzhou, Guangdong, China
| | - Peiqing Liu
- School of Pharmaceutical Sciences, Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, National and Local Joint Engineering Laboratory of Druggability and New Drugs Evaluation, Sun Yat-Sen University, Guangzhou, Guangdong, China
- School of Pharmaceutical Sciences, Jinan University, Guangzhou, Guangdong, China
| | - Min Li
- School of Pharmaceutical Sciences, Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, National and Local Joint Engineering Laboratory of Druggability and New Drugs Evaluation, Sun Yat-Sen University, Guangzhou, Guangdong, China
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9
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Chen JL, Wu X, Yin D, Jia XH, Chen X, Gu ZY, Zhu XM. Autophagy inhibitors for cancer therapy: Small molecules and nanomedicines. Pharmacol Ther 2023; 249:108485. [PMID: 37406740 DOI: 10.1016/j.pharmthera.2023.108485] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2023] [Revised: 05/27/2023] [Accepted: 06/27/2023] [Indexed: 07/07/2023]
Abstract
Autophagy is a conserved process in which the cytosolic materials are degraded and eventually recycled for cellular metabolism to maintain homeostasis. The dichotomous role of autophagy in pathogenesis is complicated. Accumulating reports have suggested that cytoprotective autophagy is responsible for tumor growth and progression. Autophagy inhibitors, such as chloroquine (CQ) and hydroxychloroquine (HCQ), are promising for treating malignancies or overcoming drug resistance in chemotherapy. With the rapid development of nanotechnology, nanomaterials also show autophagy-inhibitory effects or are reported as the carriers delivering autophagy inhibitors. In this review, we summarize the small-molecule compounds and nanomaterials inhibiting autophagic flux as well as the mechanisms involved. The nanocarrier-based drug delivery systems for autophagy inhibitors and their distinct advantages are also described. The progress of autophagy inhibitors for clinical applications is finally introduced, and their future perspectives are discussed.
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Affiliation(s)
- Jian-Li Chen
- State Key Laboratory of Quality Research in Chinese Medicine, Macau Institute for Applied Research in Medicine and Health, Macau University of Science and Technology, Taipa, Macau SAR, China
| | - Xuan Wu
- State Key Laboratory of Quality Research in Chinese Medicine, Macau Institute for Applied Research in Medicine and Health, Macau University of Science and Technology, Taipa, Macau SAR, China
| | - Dan Yin
- State Key Laboratory of Quality Research in Chinese Medicine, Macau Institute for Applied Research in Medicine and Health, Macau University of Science and Technology, Taipa, Macau SAR, China
| | - Xiao-Hui Jia
- State Key Laboratory of Quality Research in Chinese Medicine, Macau Institute for Applied Research in Medicine and Health, Macau University of Science and Technology, Taipa, Macau SAR, China
| | - Xu Chen
- State Key Laboratory of Quality Research in Chinese Medicine, Macau Institute for Applied Research in Medicine and Health, Macau University of Science and Technology, Taipa, Macau SAR, China
| | - Ze-Yun Gu
- State Key Laboratory of Quality Research in Chinese Medicine, Macau Institute for Applied Research in Medicine and Health, Macau University of Science and Technology, Taipa, Macau SAR, China
| | - Xiao-Ming Zhu
- State Key Laboratory of Quality Research in Chinese Medicine, Macau Institute for Applied Research in Medicine and Health, Macau University of Science and Technology, Taipa, Macau SAR, China.
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10
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Zhou J, Ma J, Yang C, Zhu X, Li J, Zheng X, Li X, Chen S, Feng L, Wang P, Ho MI, Ma W, Liao J, Li F, Wang C, Zhuang X, Jiang L, Kang BH, Gao C. A non-canonical role of ATG8 in Golgi recovery from heat stress in plants. NATURE PLANTS 2023; 9:749-765. [PMID: 37081290 DOI: 10.1038/s41477-023-01398-w] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Accepted: 03/22/2023] [Indexed: 05/03/2023]
Abstract
Above-optimal growth temperatures, usually referred to as heat stress (HS), pose a challenge to organisms' survival as they interfere with essential physiological functions and disrupt cellular organization. Previous studies have elucidated the complex transcriptional regulatory networks involved in plant HS responses, but the mechanisms of organellar remodelling and homeostasis during plant HS adaptations remain elusive. Here we report a non-canonical function of ATG8 in regulating the restoration of plant Golgi damaged by HS. Short-term acute HS causes vacuolation of the Golgi apparatus and translocation of ATG8 to the dilated Golgi membrane. The inactivation of the ATG conjugation system, but not of the upstream autophagic initiators, abolishes the targeting of ATG8 to the swollen Golgi, causing a delay in Golgi recovery after HS. Using TurboID-based proximity labelling, we identified CLATHRIN LIGHT CHAIN 2 (CLC2) as an interacting partner of ATG8 via the AIM-LDS interface. CLC2 is recruited to the cisternal membrane by ATG8 to facilitate Golgi reassembly. Collectively, our study reveals a hitherto unanticipated process of Golgi stack recovery from HS in plant cells and uncovers a previously unknown mechanism of organelle resilience involving ATG8.
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Affiliation(s)
- Jun Zhou
- MOE Key Laboratory & Guangdong Provincial Key Laboratory of Laser Life Science, Guangzhou Key Laboratory of Spectral Analysis and Functional Probes, College of Biophotonics, Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou, China.
| | - Juncai Ma
- School of Life Sciences, Centre for Cell & Developmental Biology and State Key Laboratory of Agrobiotechnology, Chinese University of Hong Kong, Hong Kong, China
| | - Chao Yang
- MOE Key Laboratory & Guangdong Provincial Key Laboratory of Laser Life Science, Guangzhou Key Laboratory of Spectral Analysis and Functional Probes, College of Biophotonics, Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou, China
- Guangdong Provincial Key Laboratory of Applied Botany & Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
| | - Xiu Zhu
- MOE Key Laboratory & Guangdong Provincial Key Laboratory of Laser Life Science, Guangzhou Key Laboratory of Spectral Analysis and Functional Probes, College of Biophotonics, Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou, China
| | - Jing Li
- School of Life Sciences, Centre for Cell & Developmental Biology and State Key Laboratory of Agrobiotechnology, Chinese University of Hong Kong, Hong Kong, China
| | - Xuanang Zheng
- MOE Key Laboratory & Guangdong Provincial Key Laboratory of Laser Life Science, Guangzhou Key Laboratory of Spectral Analysis and Functional Probes, College of Biophotonics, Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou, China
| | - Xibao Li
- MOE Key Laboratory & Guangdong Provincial Key Laboratory of Laser Life Science, Guangzhou Key Laboratory of Spectral Analysis and Functional Probes, College of Biophotonics, Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou, China
| | - Siyu Chen
- MOE Key Laboratory & Guangdong Provincial Key Laboratory of Laser Life Science, Guangzhou Key Laboratory of Spectral Analysis and Functional Probes, College of Biophotonics, Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou, China
| | - Lei Feng
- MOE Key Laboratory & Guangdong Provincial Key Laboratory of Laser Life Science, Guangzhou Key Laboratory of Spectral Analysis and Functional Probes, College of Biophotonics, Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou, China
- School of Life Sciences, Centre for Cell & Developmental Biology and State Key Laboratory of Agrobiotechnology, Chinese University of Hong Kong, Hong Kong, China
| | - Pengfei Wang
- School of Life Sciences, Centre for Cell & Developmental Biology and State Key Laboratory of Agrobiotechnology, Chinese University of Hong Kong, Hong Kong, China
| | - Man Ip Ho
- School of Life Sciences, Centre for Cell & Developmental Biology and State Key Laboratory of Agrobiotechnology, Chinese University of Hong Kong, Hong Kong, China
| | - Wenlong Ma
- School of Life Sciences, Centre for Cell & Developmental Biology and State Key Laboratory of Agrobiotechnology, Chinese University of Hong Kong, Hong Kong, China
| | - Jun Liao
- MOE Key Laboratory & Guangdong Provincial Key Laboratory of Laser Life Science, Guangzhou Key Laboratory of Spectral Analysis and Functional Probes, College of Biophotonics, Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou, China
| | - Faqiang Li
- College of Life Sciences, South China Agricultural University, Guangzhou, China
| | - Chao Wang
- College of Life Sciences, Shaoxing University, Shaoxing, China
| | - Xiaohong Zhuang
- School of Life Sciences, Centre for Cell & Developmental Biology and State Key Laboratory of Agrobiotechnology, Chinese University of Hong Kong, Hong Kong, China
| | - Liwen Jiang
- School of Life Sciences, Centre for Cell & Developmental Biology and State Key Laboratory of Agrobiotechnology, Chinese University of Hong Kong, Hong Kong, China
| | - Byung-Ho Kang
- School of Life Sciences, Centre for Cell & Developmental Biology and State Key Laboratory of Agrobiotechnology, Chinese University of Hong Kong, Hong Kong, China.
| | - Caiji Gao
- MOE Key Laboratory & Guangdong Provincial Key Laboratory of Laser Life Science, Guangzhou Key Laboratory of Spectral Analysis and Functional Probes, College of Biophotonics, Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou, China.
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11
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Hirao H, Kojima H, Dery KJ, Nakamura K, Kadono K, Zhai Y, Farmer DG, Kaldas FM, Kupiec-Weglinski JW. Neutrophil CEACAM1 determines susceptibility to NETosis by regulating the S1PR2/S1PR3 axis in liver transplantation. J Clin Invest 2023; 133:e162940. [PMID: 36719377 PMCID: PMC9888387 DOI: 10.1172/jci162940] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Accepted: 11/17/2022] [Indexed: 02/01/2023] Open
Abstract
Neutrophils, the largest innate immune cell population in humans, are the primary proinflammatory sentinel in the ischemia-reperfusion injury (IRI) mechanism in orthotopic liver transplantation (OLT). Carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1, CC1, or CD66a) is essential in neutrophil activation and serves as a checkpoint regulator of innate immune-driven IRI cascade in OLT. Although CC1 alternative splicing generates two functionally distinct short and long cytoplasmic isoforms, their role in neutrophil activation remains unknown. Here, we undertook molecular and functional studies to interrogate the significance of neutrophil CC1 signaling in mouse and human OLT recipients. In the experimental arm, we employed a mouse OLT model to document that ablation of recipient-derived neutrophil CC1-long (CC1-L) isotype aggravated hepatic IRI by promoting neutrophil extracellular traps (NETs). Notably, by regulating the S1P-S1PR2/S1PR3 axis, neutrophil CC1-L determined susceptibility to NET formation via autophagy signaling. In the clinical arm, liver grafts from 55 transplant patients selectively enriched for neutrophil CC1-L showed relative resistance to ischemia-reperfusion (IR) stress/tissue damage, improved hepatocellular function, and clinical outcomes. In conclusion, despite neutrophils being considered a principal villain in peritransplant tissue injury, their CC1-L isoform may serve as a regulator of IR stress resistance/NETosis in human and mouse OLT recipients.
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Affiliation(s)
- Hirofumi Hirao
- Dumont-UCLA Transplantation Center, Department of Surgery, Division of Liver and Pancreas Transplantation, David Geffen School of Medicine at UCLA, Los Angeles, California, USA
| | - Hidenobu Kojima
- Dumont-UCLA Transplantation Center, Department of Surgery, Division of Liver and Pancreas Transplantation, David Geffen School of Medicine at UCLA, Los Angeles, California, USA
| | - Kenneth J. Dery
- Dumont-UCLA Transplantation Center, Department of Surgery, Division of Liver and Pancreas Transplantation, David Geffen School of Medicine at UCLA, Los Angeles, California, USA
| | - Kojiro Nakamura
- Dumont-UCLA Transplantation Center, Department of Surgery, Division of Liver and Pancreas Transplantation, David Geffen School of Medicine at UCLA, Los Angeles, California, USA
- Department of Surgery, Division of Hepato-Biliary-Pancreatic Surgery and Transplantation, Department of Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Kentaro Kadono
- Dumont-UCLA Transplantation Center, Department of Surgery, Division of Liver and Pancreas Transplantation, David Geffen School of Medicine at UCLA, Los Angeles, California, USA
| | - Yuan Zhai
- Dumont-UCLA Transplantation Center, Department of Surgery, Division of Liver and Pancreas Transplantation, David Geffen School of Medicine at UCLA, Los Angeles, California, USA
| | - Douglas G. Farmer
- Dumont-UCLA Transplantation Center, Department of Surgery, Division of Liver and Pancreas Transplantation, David Geffen School of Medicine at UCLA, Los Angeles, California, USA
| | - Fady M. Kaldas
- Dumont-UCLA Transplantation Center, Department of Surgery, Division of Liver and Pancreas Transplantation, David Geffen School of Medicine at UCLA, Los Angeles, California, USA
| | - Jerzy W. Kupiec-Weglinski
- Dumont-UCLA Transplantation Center, Department of Surgery, Division of Liver and Pancreas Transplantation, David Geffen School of Medicine at UCLA, Los Angeles, California, USA
- Department of Pathology and Laboratory Medicine, David Geffen School of Medicine at UCLA, Los Angeles, California, USA
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12
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Lu Q, Chen Y, Li J, Zhu F, Zheng Z. Crosstalk between cGAS-STING pathway and autophagy in cancer immunity. Front Immunol 2023; 14:1139595. [PMID: 36936940 PMCID: PMC10014609 DOI: 10.3389/fimmu.2023.1139595] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2023] [Accepted: 02/20/2023] [Indexed: 03/05/2023] Open
Abstract
The cyclic GMP-AMP synthase-stimulator of interferon genes (cGAS-STING) pathway is critical in cancer immunity. Autophagy is a highly conserved process that is responsible for the degradation of cytoplasmic material and is involved in both innate and adaptive immunity. Recently, cGAS-STING and autophagy have been shown to be interconnected, which may influence the progression of cancer. Although cGAS-STING and autophagy have been shown to be interrelated in innate immunity, little has been reported about cancer immunity. As cancer immunity is key to treating tumors, it is essential to summarize the relationship and interactions between the two. Based on this, we systematically sorted out the recent findings of cGAS-STING and autophagy in cancer immunity and explored the interactions between cGAS-STING and autophagy, although these interactions have not been extensively studied. Lastly, we provide an outlook on how cGAS-STING and autophagy can be combined, with the hope that our research can help people better understand their potential roles in cancer immunity and bring light to the treatment of cancer.
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Affiliation(s)
- Qijun Lu
- Department of Oncology, Longhua Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Yukun Chen
- Cancer Institute, Longhua Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Jianwen Li
- Department of Oncology, Longhua Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Feng Zhu
- Department of Laboratory Medicine, Huadong Hospital, Fudan University, Shanghai, China
| | - Zhan Zheng
- Department of Oncology, Longhua Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China
- *Correspondence: Zhan Zheng,
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13
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Zhang Z, Zhou H, Ouyang X, Dong Y, Sarapultsev A, Luo S, Hu D. Multifaceted functions of STING in human health and disease: from molecular mechanism to targeted strategy. Signal Transduct Target Ther 2022; 7:394. [PMID: 36550103 PMCID: PMC9780328 DOI: 10.1038/s41392-022-01252-z] [Citation(s) in RCA: 41] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Revised: 10/25/2022] [Accepted: 11/09/2022] [Indexed: 12/24/2022] Open
Abstract
Since the discovery of Stimulator of Interferon Genes (STING) as an important pivot for cytosolic DNA sensation and interferon (IFN) induction, intensive efforts have been endeavored to clarify the molecular mechanism of its activation, its physiological function as a ubiquitously expressed protein, and to explore its potential as a therapeutic target in a wide range of immune-related diseases. With its orthodox ligand 2'3'-cyclic GMP-AMP (2'3'-cGAMP) and the upstream sensor 2'3'-cGAMP synthase (cGAS) to be found, STING acquires its central functionality in the best-studied signaling cascade, namely the cGAS-STING-IFN pathway. However, recently updated research through structural research, genetic screening, and biochemical assay greatly extends the current knowledge of STING biology. A second ligand pocket was recently discovered in the transmembrane domain for a synthetic agonist. On its downstream outputs, accumulating studies sketch primordial and multifaceted roles of STING beyond its cytokine-inducing function, such as autophagy, cell death, metabolic modulation, endoplasmic reticulum (ER) stress, and RNA virus restriction. Furthermore, with the expansion of the STING interactome, the details of STING trafficking also get clearer. After retrospecting the brief history of viral interference and the milestone events since the discovery of STING, we present a vivid panorama of STING biology taking into account the details of the biochemical assay and structural information, especially its versatile outputs and functions beyond IFN induction. We also summarize the roles of STING in the pathogenesis of various diseases and highlight the development of small-molecular compounds targeting STING for disease treatment in combination with the latest research. Finally, we discuss the open questions imperative to answer.
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Affiliation(s)
- Zili Zhang
- Department of Integrated Traditional Chinese and Western Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 430022, Wuhan, China
| | - Haifeng Zhou
- Department of Integrated Traditional Chinese and Western Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 430022, Wuhan, China
| | - Xiaohu Ouyang
- Department of Integrated Traditional Chinese and Western Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 430022, Wuhan, China
| | - Yalan Dong
- Department of Integrated Traditional Chinese and Western Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 430022, Wuhan, China
| | - Alexey Sarapultsev
- Institute of Immunology and Physiology, Ural Branch of the Russian Academy of Science, 620049, Ekaterinburg, Russia
| | - Shanshan Luo
- Institute of Hematology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
| | - Desheng Hu
- Department of Integrated Traditional Chinese and Western Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 430022, Wuhan, China.
- Key Laboratory of Biological Targeted Therapy, The Ministry of Education, 430022, Wuhan, China.
- Clinical Research Center of Cancer Immunotherapy, 430022, Hubei, Wuhan, China.
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14
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Intercellular transfer of activated STING triggered by RAB22A-mediated non-canonical autophagy promotes antitumor immunity. Cell Res 2022; 32:1086-1104. [PMID: 36280710 PMCID: PMC9715632 DOI: 10.1038/s41422-022-00731-w] [Citation(s) in RCA: 33] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Accepted: 09/16/2022] [Indexed: 01/31/2023] Open
Abstract
STING, an endoplasmic reticulum (ER) transmembrane protein, mediates innate immune activation upon cGAMP stimulation and is degraded through autophagy. Here, we report that activated STING could be transferred between cells to promote antitumor immunity, a process triggered by RAB22A-mediated non-canonical autophagy. Mechanistically, RAB22A engages PI4K2A to generate PI4P that recruits the Atg12-Atg5-Atg16L1 complex, inducing the formation of ER-derived RAB22A-mediated non-canonical autophagosome, in which STING activated by agonists or chemoradiotherapy is packaged. This RAB22A-induced autophagosome fuses with RAB22A-positive early endosome, generating a new organelle that we name Rafeesome (RAB22A-mediated non-canonical autophagosome fused with early endosome). Meanwhile, RAB22A inactivates RAB7 to suppress the fusion of Rafeesome with lysosome, thereby enabling the secretion of the inner vesicle of the autophagosome bearing activated STING as a new type of extracellular vesicle that we define as R-EV (RAB22A-induced extracellular vesicle). Activated STING-containing R-EVs induce IFNβ release from recipient cells to the tumor microenvironment, promoting antitumor immunity. Consistently, RAB22A enhances the antitumor effect of the STING agonist diABZI in mice, and a high RAB22A level predicts good survival in nasopharyngeal cancer patients treated with chemoradiotherapy. Our findings reveal that Rafeesome regulates the intercellular transfer of activated STING to trigger and spread antitumor immunity, and that the inner vesicle of non-canonical autophagosome originated from ER is secreted as R-EV, providing a new perspective for understanding the intercellular communication of organelle membrane proteins.
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15
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Ding Y, Xing D, Fei Y, Lu B. Emerging degrader technologies engaging lysosomal pathways. Chem Soc Rev 2022; 51:8832-8876. [PMID: 36218065 PMCID: PMC9620493 DOI: 10.1039/d2cs00624c] [Citation(s) in RCA: 32] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2022] [Indexed: 08/24/2023]
Abstract
Targeted protein degradation (TPD) provides unprecedented opportunities for drug discovery. While the proteolysis-targeting chimera (PROTAC) technology has already entered clinical trials and changed the landscape of small-molecule drugs, new degrader technologies harnessing alternative degradation machineries, especially lysosomal pathways, have emerged and broadened the spectrum of degradable targets. We have recently proposed the concept of autophagy-tethering compounds (ATTECs) that hijack the autophagy protein microtubule-associated protein 1A/1B light chain 3 (LC3) for targeted degradation. Other groups also reported degrader technologies engaging lysosomal pathways through different mechanisms including AUTACs, AUTOTACs, LYTACs and MoDE-As. In this review, we analyse and discuss ATTECs along with other lysosomal-relevant degrader technologies. Finally, we will briefly summarize the current status of these degrader technologies and envision possible future studies.
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Affiliation(s)
- Yu Ding
- Neurology Department at Huashan Hospital, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, School of Life Sciences, Fudan University, Shanghai, China.
| | - Dong Xing
- Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai, China.
| | - Yiyan Fei
- Department of Optical Science and Engineering, Shanghai Engineering Research Center of Ultra-Precision Optical Manufacturing, Key Laboratory of Micro and Nano Photonic Structures (Ministry of Education), Fudan University, Shanghai, China.
| | - Boxun Lu
- Neurology Department at Huashan Hospital, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, School of Life Sciences, Fudan University, Shanghai, China.
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16
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Durgan J, Florey O. Many roads lead to CASM: Diverse stimuli of noncanonical autophagy share a unifying molecular mechanism. SCIENCE ADVANCES 2022; 8:eabo1274. [PMID: 36288315 PMCID: PMC9604613 DOI: 10.1126/sciadv.abo1274] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Autophagy is a fundamental catabolic process coordinated by a network of autophagy-related (ATG) proteins. These ATG proteins also perform an important parallel role in "noncanonical" autophagy, a lysosome-associated signaling pathway with key functions in immunity, inflammation, cancer, and neurodegeneration. While the noncanonical autophagy pathway shares the common ATG machinery, it bears key mechanistic and functional distinctions, and is characterized by conjugation of ATG8 to single membranes (CASM). Here, we review the diverse, and still expanding, collection of stimuli and processes now known to harness the noncanonical autophagy pathway, including engulfment processes, drug treatments, TRPML1 and STING signaling, viral infection, and other pathogenic factors. We discuss the multiple associated routes to CASM and assess their shared and distinctive molecular features. By integrating these findings, we propose an updated and unifying mechanism for noncanonical autophagy, centered on ATG16L1 and V-ATPase.
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17
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Gitogenin suppresses lung cancer progression by inducing apoptosis and autophagy initiation through the activation of AMPK signaling. Int Immunopharmacol 2022; 111:108806. [PMID: 35914447 DOI: 10.1016/j.intimp.2022.108806] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2020] [Revised: 04/18/2022] [Accepted: 04/24/2022] [Indexed: 11/22/2022]
Abstract
Lung cancer is a leading cause of tumor-associated death worldwide. Autophagy plays a key role in regulating lung cancer progression, and is a promising option for lung cancer treatment. Saponins are a group of naturally occurring plant glycosides, characterized by their strong foam-forming properties in aqueous solution, and exert various biological properties, such as anti-inflammation and anti-cancer. In the present study, we for the first time explored the effects of gitogenin (GIT), an important saponin derived from Tribulus longipetalus, on lung cancer progression both in vitro and in vivo. We found that GIT markedly reduced the proliferation and induced apoptosis in lung cancer cells through increasing the cleavage of Caspase-3 and poly (ADP-ribose) polymerases (PARPs). In addition, GIT-incubated lung cancer cells exhibited clear accumulation of autophagosome, which was essential for GIT-suppressed lung cancer. Mechanistically, GIT-induced autophagy initiation was mainly through activating AMP-activated protein kinase (AMPK) and blocking protein kinase B (AKT) signaling pathways, respectively. Moreover, the autophagic flux was disrupted in GIT-treated lung cancer cells, contributing to the accumulation of impaired autophagolysosomes. Importantly, we found that suppressing autophagy initiation could abolish GIT-induced cell death; however, autophagosomes accumulation sensitized lung cancer cells to cell death upon GIT treatment. More in vitro experiments showed that GIT led to reactive oxygen species (ROS) production in lung cancer cells, which was also involved in the modulation of apoptosis. The in vivo findings confirmed the effects of GIT against lung cancer progression with undetectable toxicity to organs. In conclusion, we provided new insights into the treatment of lung cancer, and GIT might be an effective strategy for future clinical application.
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18
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Maintaining Golgi Homeostasis: A Balancing Act of Two Proteolytic Pathways. Cells 2022; 11:cells11050780. [PMID: 35269404 PMCID: PMC8909885 DOI: 10.3390/cells11050780] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Revised: 02/18/2022] [Accepted: 02/21/2022] [Indexed: 02/06/2023] Open
Abstract
The Golgi apparatus is a central hub for cellular protein trafficking and signaling. Golgi structure and function is tightly coupled and undergoes dynamic changes in health and disease. A crucial requirement for maintaining Golgi homeostasis is the ability of the Golgi to target aberrant, misfolded, or otherwise unwanted proteins to degradation. Recent studies have revealed that the Golgi apparatus may degrade such proteins through autophagy, retrograde trafficking to the ER for ER-associated degradation (ERAD), and locally, through Golgi apparatus-related degradation (GARD). Here, we review recent discoveries in these mechanisms, highlighting the role of the Golgi in maintaining cellular homeostasis.
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19
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Polystyrene microplastics induce an immunometabolic active state in macrophages. Cell Biol Toxicol 2022; 38:31-41. [PMID: 34021430 PMCID: PMC8606615 DOI: 10.1007/s10565-021-09616-x] [Citation(s) in RCA: 29] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Accepted: 05/06/2021] [Indexed: 02/06/2023]
Abstract
Anti-inflammatory and proinflammatory responses in macrophages are influenced by cellular metabolism. Macrophages are the primary phagocyte in mucosal environments (i.e., intestinal tract and lungs) acting as first-line defense against microorganisms and environmental pollutants. Given the extensive contamination of our food and water sources with microplastics, we aimed to examine the metabolic response in macrophages to microplastic particles (MPs). Utilizing murine macrophages, we assessed the metabolic response of macrophages after polystyrene MP phagocytosis. The phagocytosis of MP by macrophages induced a metabolic shift toward glycolysis and a reduction in mitochondrial respiration that was associated with an increase of cell surface markers CD80 and CD86 and cytokine gene expression associated with glycolysis. The gastrointestinal consequences of this metabolic switch in the context of an immune response remain uncertain, but the global rise of plastic pollution and MP ingestion potentially poses an unappreciated health risk. Macrophage phagocytosis of microplastics alters cellular metabolism. - Macrophages cannot degrade PS MP. - MP phagocytosis increases glycolysis in murine macrophages. - MP phagocytosis reduces mitochondrial respiration in murine macrophages.
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20
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Zhao Y, Wang C, Goel A. A combined treatment with melatonin and andrographis promotes autophagy and anticancer activity in colorectal cancer. Carcinogenesis 2022; 43:217-230. [PMID: 35089340 PMCID: PMC9036994 DOI: 10.1093/carcin/bgac008] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Revised: 12/31/2021] [Accepted: 01/25/2022] [Indexed: 01/30/2023] Open
Abstract
Colorectal cancer (CRC) is one of the most frequent malignancies worldwide and remains one of the leading causes of cancer-related deaths in the USA. The high degree of morbidity and mortality associated with this disease is largely due to the inadequate efficacy of current treatments as well the development of chemoresistance. In recent years, several pharmaceutical agents screened from natural products have shown the promise to offer a safe, inexpensive and synergistically multi-targeted treatment option in various cancers. Given the growing evidence of anti-carcinogenic properties of two natural compounds, melatonin (MLT) and andrographis (Andro), we aimed to evaluate their synergistic anticancer effects in CRC. We demonstrate that indeed these two compounds possessed a synergistic anticancer effect in terms of their ability to inhibit cell viability, suppression of colony-formation and induction of apoptosis (P < 0.05). In line with our in vitro findings, we were able to validate this combinatorial anticancer activity in xenograft animal models (P < 0.001) as well as tumor-derived 3D organoids (P < 0.01). RNA-sequencing analysis revealed candidate pathways and genes that mediated antitumor efficacy of MLT and Andro in CRC, among which autophagy pathway and related genes, including NR4A1, CTSL and Atg12, were found to be primarily responsible for the increased anticancer effect by the two natural products. In conclusion, our data reveal a potent and synergistic therapeutic effect of MLT and Andro in the treatment of CRC and provides a rationale for suppressing autophagy in cancer cells as a potential therapeutic strategy for CRC.
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Affiliation(s)
- Yinghui Zhao
- Department of Molecular Diagnostics and Experimental Therapeutics, Beckman Research Institute of City of Hope, Biomedical Research Center, Monrovia, CA, USA,Department of Clinical Laboratory, The Second Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Chuanxin Wang
- Department of Clinical Laboratory, The Second Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China,Shandong Engineering & Technology Research Center for Tumor Marker Detection, Jinan, China,Shandong Provincial Clinical Medicine Research Center for Clinical Laboratory, Jinan, China
| | - Ajay Goel
- To whom correspondence should be addressed. City of Hope Comprehensive Cancer Center, 1218 S. Fifth Avenue, Monrovia, CA 91016, USA. Tel: +1 626-218-3452;
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21
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Xu Y, Cheng S, Zeng H, Zhou P, Ma Y, Li L, Liu X, Shao F, Ding J. ARF GTPases activate Salmonella effector SopF to ADP-ribosylate host V-ATPase and inhibit endomembrane damage-induced autophagy. Nat Struct Mol Biol 2022; 29:67-77. [PMID: 35046574 DOI: 10.1038/s41594-021-00710-6] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Accepted: 12/02/2021] [Indexed: 12/19/2022]
Abstract
Selective autophagy helps eukaryotes to cope with endogenous dangers or foreign invaders; its initiation often involves membrane damage. By studying a Salmonella effector SopF, we recently identified the vacuolar ATPase (V-ATPase)-ATG16L1 axis that initiates bacteria-induced autophagy. Here we show that SopF is an ADP-ribosyltransferase specifically modifying Gln124 of ATP6V0C in V-ATPase. We identify GTP-bound ADP-ribosylation factor (ARF) GTPases as a cofactor required for SopF functioning. Crystal structures of SopF-ARF1 complexes not only reveal structural basis of SopF ADP-ribosyltransferase activity but also a unique effector-binding mode adopted by ARF GTPases. Further, the N terminus of ARF1, although dispensable for high-affinity binding to SopF, is critical for activating SopF to modify ATP6V0C. Moreover, lysosome or Golgi damage-induced autophagic LC3 activation is inhibited by SopF or Q124A mutation of ATP6V0C, thus also mediated by the V-ATPase-ATG16L1 axis. In this process, the V-ATPase functions to sense membrane damages, which can be uncoupled from its proton-pumping activity.
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Affiliation(s)
- Yue Xu
- National Institute of Biological Sciences, Beijing, China.,Department of Pathophysiology, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Sen Cheng
- Institute of Analytical Chemistry and Synthetic and Functional Biomolecules Center, College of Chemistry and Molecular Engineering, Peking University, Beijing, China.,Department of Microbiology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China
| | - Huan Zeng
- National Institute of Biological Sciences, Beijing, China.,National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Ping Zhou
- National Institute of Biological Sciences, Beijing, China
| | - Yan Ma
- National Institute of Biological Sciences, Beijing, China
| | - Lin Li
- National Institute of Biological Sciences, Beijing, China
| | - Xiaoyun Liu
- Institute of Analytical Chemistry and Synthetic and Functional Biomolecules Center, College of Chemistry and Molecular Engineering, Peking University, Beijing, China.,Department of Microbiology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China
| | - Feng Shao
- National Institute of Biological Sciences, Beijing, China. .,National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China. .,Research Unit of Pyroptosis and Immunity, Chinese Academy of Medical Sciences and National Institute of Biological Sciences, Beijing, China. .,Tsinghua Institute of Multidisciplinary Biomedical Research, Tsinghua University, Beijing, China.
| | - Jingjin Ding
- National Institute of Biological Sciences, Beijing, China. .,National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China.
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22
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Fote GM, Geller NR, Efstathiou NE, Hendricks N, Vavvas DG, Reidling JC, Thompson LM, Steffan JS. Isoform-dependent lysosomal degradation and internalization of apolipoprotein E requires autophagy proteins. J Cell Sci 2022; 135:jcs258687. [PMID: 34982109 PMCID: PMC8917355 DOI: 10.1242/jcs.258687] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Accepted: 12/17/2021] [Indexed: 12/09/2022] Open
Abstract
The human apolipoprotein E4 isoform (APOE4) is the strongest genetic risk factor for late-onset Alzheimer's disease (AD), and lysosomal dysfunction has been implicated in AD pathogenesis. We found, by examining cells stably expressing each APOE isoform, that APOE4 increases lysosomal trafficking, accumulates in enlarged lysosomes and late endosomes, alters autophagic flux and the abundance of autophagy proteins and lipid droplets, and alters the proteomic contents of lysosomes following internalization. We investigated APOE-related lysosomal trafficking further in cell culture, and found that APOE from the post-Golgi compartment is degraded through autophagy. We found that this autophagic process requires the lysosomal membrane protein LAMP2 in immortalized neuron-like and hepatic cells, and in mouse brain tissue. Several macroautophagy-associated proteins were also required for autophagic degradation and internalization of APOE in hepatic cells. The dysregulated autophagic flux and lysosomal trafficking of APOE4 that we observed suggest a possible novel mechanism that might contribute to AD pathogenesis. This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Gianna M. Fote
- UC Irvine Department of Biological Chemistry, 825 Health Sciences Road, Medical Sciences I, Room D240, UC Irvine School of Medicine, Irvine, CA 92697-1700, USA
| | - Nicolette R. Geller
- UC Irvine Department of Psychiatry and Human Behavior, Neuropsychiatric Center, UC Irvine Medical Center, 101 The City Drive South, Building 3, Route 88, Orange, CA 92868, USA
| | - Nikolaos E. Efstathiou
- Harvard Medical School Department of Ophthalmology, 243 Charles Street, Boston, MA 02114, USA
| | - Nathan Hendricks
- Institute for Integrative Genome Biology, UC Riverside, Eucalyptus Drive, Riverside, CA 92521, USA
| | - Demetrios G. Vavvas
- Harvard Medical School Department of Ophthalmology, 243 Charles Street, Boston, MA 02114, USA
| | - Jack C. Reidling
- UC Irvine MIND Institute, 2642 Biological Sciences III, Irvine, CA 92697-4545, USA
| | - Leslie M. Thompson
- UC Irvine Department of Biological Chemistry, 825 Health Sciences Road, Medical Sciences I, Room D240, UC Irvine School of Medicine, Irvine, CA 92697-1700, USA
- UC Irvine Department of Psychiatry and Human Behavior, Neuropsychiatric Center, UC Irvine Medical Center, 101 The City Drive South, Building 3, Route 88, Orange, CA 92868, USA
- UC Irvine MIND Institute, 2642 Biological Sciences III, Irvine, CA 92697-4545, USA
- UC Irvine Department of Neurobiology and Behavior, 2205 McGaugh Hall, Irvine, CA 92697, USA
| | - Joan S. Steffan
- UC Irvine Department of Psychiatry and Human Behavior, Neuropsychiatric Center, UC Irvine Medical Center, 101 The City Drive South, Building 3, Route 88, Orange, CA 92868, USA
- UC Irvine MIND Institute, 2642 Biological Sciences III, Irvine, CA 92697-4545, USA
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23
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Robust LC3B lipidation analysis by precisely adjusting autophagic flux. Sci Rep 2022; 12:79. [PMID: 34996966 PMCID: PMC8742033 DOI: 10.1038/s41598-021-03875-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Accepted: 12/06/2021] [Indexed: 12/20/2022] Open
Abstract
Autophagic flux can be quantified based on the accumulation of lipidated LC3B in the presence of late-stage autophagy inhibitors. This method has been widely applied to identify novel compounds that activate autophagy. Here we scrutinize this approach and show that bafilomycin A1 (BafA) but not chloroquine is suitable for flux quantification due to the stimulating effect of chloroquine on non-canonical LC3B-lipidation. Significant autophagic flux increase by rapamycin could only be observed when combining it with BafA concentrations not affecting basal flux, a condition which created a bottleneck, rather than fully blocking autophagosome-lysosome fusion, concomitant with autophagy stimulation. When rapamycin was combined with saturating concentrations of BafA, no significant further increase of LC3B lipidation could be detected over the levels induced by the late-stage inhibitor. The large assay window obtained by this approach enables an effective discrimination of autophagy activators based on their cellular potency. To demonstrate the validity of this approach, we show that a novel inhibitor of the acetyltransferase EP300 activates autophagy in a mTORC1-dependent manner. We propose that the creation of a sensitized background rather than a full block of autophagosome progression is required to quantitatively capture changes in autophagic flux.
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24
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Durgan J, Lystad AH, Sloan K, Carlsson SR, Wilson MI, Marcassa E, Ulferts R, Webster J, Lopez-Clavijo AF, Wakelam MJ, Beale R, Simonsen A, Oxley D, Florey O. Non-canonical autophagy drives alternative ATG8 conjugation to phosphatidylserine. Mol Cell 2021; 81:2031-2040.e8. [PMID: 33909989 PMCID: PMC8122138 DOI: 10.1016/j.molcel.2021.03.020] [Citation(s) in RCA: 93] [Impact Index Per Article: 31.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Revised: 01/15/2021] [Accepted: 03/16/2021] [Indexed: 01/22/2023]
Abstract
Autophagy is a fundamental catabolic process that uses a unique post-translational modification, the conjugation of ATG8 protein to phosphatidylethanolamine (PE). ATG8 lipidation also occurs during non-canonical autophagy, a parallel pathway involving conjugation of ATG8 to single membranes (CASM) at endolysosomal compartments, with key functions in immunity, vision, and neurobiology. It is widely assumed that CASM involves the same conjugation of ATG8 to PE, but this has not been formally tested. Here, we discover that all ATG8s can also undergo alternative lipidation to phosphatidylserine (PS) during CASM, induced pharmacologically, by LC3-associated phagocytosis or influenza A virus infection, in mammalian cells. Importantly, ATG8-PS and ATG8-PE adducts are differentially delipidated by the ATG4 family and bear different cellular dynamics, indicating significant molecular distinctions. These results provide important insights into autophagy signaling, revealing an alternative form of the hallmark ATG8 lipidation event. Furthermore, ATG8-PS provides a specific "molecular signature" for the non-canonical autophagy pathway.
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Affiliation(s)
- Joanne Durgan
- Signalling Programme, Babraham Institute, Cambridge, UK
| | - Alf H Lystad
- Department of Molecular Medicine, University of Oslo, Oslo, Norway
| | | | - Sven R Carlsson
- Department of Medical Biochemistry and Biophysics, Umeå University, Umeå, Sweden
| | | | | | | | - Judith Webster
- Mass Spectrometry Facility, Babraham Institute, Cambridge, UK
| | | | - Michael J Wakelam
- Signalling Programme, Babraham Institute, Cambridge, UK; Lipidomics Facility, Babraham Institute, Cambridge, UK
| | | | - Anne Simonsen
- Department of Molecular Medicine, University of Oslo, Oslo, Norway
| | - David Oxley
- Mass Spectrometry Facility, Babraham Institute, Cambridge, UK
| | - Oliver Florey
- Signalling Programme, Babraham Institute, Cambridge, UK.
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25
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Zheng J, Wei S, Xiao T, Li G. LC3B/p62-mediated mitophagy protects A549 cells from resveratrol-induced apoptosis. Life Sci 2021; 271:119139. [PMID: 33539914 DOI: 10.1016/j.lfs.2021.119139] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Revised: 12/29/2020] [Accepted: 01/14/2021] [Indexed: 02/05/2023]
Abstract
AIMS Complicated mechanisms in cancer cells have been restricting the medicinal value of resveratrol (Res). The mechanisms by which Res exerts its anti-tumor activity in lung cancer cells have diverged among reports in recent years, whether cells choose to undergo autophagic cell death or apoptosis remains controversial. Yet, whether Res-induced autophagic cell death transforms into apoptosis is still unknown, and by which autophagy regulates programmed cell death is still undefined. MAIN METHODS Here, A549 cells were treated with Res to investigate the mechanisms of autophagy and apoptosis using western blot, immunofluorescence staining for LC3B. KEY FINDINGS Non-canonical autophagy was induced by Res-treatment in a Beclin-1- and ATG5-independent manner, with apoptosis being activated simultaneously. Autophagy induced by Res was activated by rapamycin with decreased apoptosis, suggesting that autophagy may serve as a protective pathway in cells. Mitophagy was found to be induced by Res using fluorescence co-localization of mitochondria with lysosomes. Subsequently, it was identified that mitophagy was mediated by LC3B/p62 interaction and could be inhibited by LC3B knockout and p62 knockdown following increased apoptosis. SIGNIFICANCE In conclusion, the current results demonstrate that Res-induced non-canonical autophagy in A549 lung cancer cells with apoptosis activation simultaneously, while LC3B/p62-mediated mitophagy protects tumor cells against apoptosis, providing novel mechanisms about the critical role of mitophagy in regulating cell fate.
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Affiliation(s)
- Jiahua Zheng
- Open Laboratory for Tumor Molecular Biology/Department of Biochemistry/The Key Laboratory of Molecular Biology for High Cancer Incidence Coastal Chaoshan Area, Shantou University Medical College, Xinling Road 22, Shantou, China
| | - Shaochai Wei
- Open Laboratory for Tumor Molecular Biology/Department of Biochemistry/The Key Laboratory of Molecular Biology for High Cancer Incidence Coastal Chaoshan Area, Shantou University Medical College, Xinling Road 22, Shantou, China
| | - Tingting Xiao
- Open Laboratory for Tumor Molecular Biology/Department of Biochemistry/The Key Laboratory of Molecular Biology for High Cancer Incidence Coastal Chaoshan Area, Shantou University Medical College, Xinling Road 22, Shantou, China
| | - Guanwu Li
- Open Laboratory for Tumor Molecular Biology/Department of Biochemistry/The Key Laboratory of Molecular Biology for High Cancer Incidence Coastal Chaoshan Area, Shantou University Medical College, Xinling Road 22, Shantou, China.
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26
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Wu W, Wang X, Sun Y, Berleth N, Deitersen J, Schlütermann D, Stuhldreier F, Wallot-Hieke N, José Mendiburo M, Cox J, Peter C, Bergmann AK, Stork B. TNF-induced necroptosis initiates early autophagy events via RIPK3-dependent AMPK activation, but inhibits late autophagy. Autophagy 2021; 17:3992-4009. [PMID: 33779513 PMCID: PMC8726653 DOI: 10.1080/15548627.2021.1899667] [Citation(s) in RCA: 46] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Macroautophagy/autophagy and necroptosis represent two opposing cellular s tress responses. Whereas autophagy primarily fulfills a cyto-protective function, necroptosis is a form of regulated cell death induced via death receptors. Here, we aimed at investigating the molecular crosstalk between these two pathways. We observed that RIPK3 directly associates with AMPK and phosphorylates its catalytic subunit PRKAA1/2 at T183/T172. Activated AMPK then phosphorylates the autophagy-regulating proteins ULK1 and BECN1. However, the lysosomal degradation of autophagosomes is blocked by TNF-induced necroptosis. Specifically, we observed dysregulated SNARE complexes upon TNF treatment; e.g., reduced levels of full-length STX17. In summary, we identified RIPK3 as an AMPK-activating kinase and thus a direct link between autophagy- and necroptosis-regulating kinases. Abbreviations: ACACA/ACC: acetyl-CoA carboxylase alpha; AMPK: AMP-activated protein kinase; ATG: autophagy-related; BECN1: beclin 1; GFP: green fluorescent protein; EBSS: Earle’s balanced salt solution; Hs: Homo sapiens; KO: knockout; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; MEF: mouse embryonic fibroblast; MLKL: mixed lineage kinase domain like pseudokinase; Mm: Mus musculus; MTOR: mechanistic target of rapamycin kinase; MVB: multivesicular body; PIK3C3/VPS34: phosphatidylinositol 3-kinase catalytic subunit type 3; PIK3R4/VPS15: phosphoinositide-3-kinase regulatory subunit 4; PLA: proximity ligation assay; PRKAA1: protein kinase AMP-activated catalytic subunit alpha 1; PRKAA2: protein kinase AMP-activated catalytic subunit alpha 2; PRKAB2: protein kinase AMP-activated non-catalytic subunit beta 2; PRKAG1: protein kinase AMP-activated non-catalytic subunit gamma 1; PtdIns3K: phosphatidylinositol 3-kinase; PtdIns3P: phosphatidylinositol-3-phosphate; RIPK1: receptor interacting serine/threonine kinase 1; RIPK3: receptor interacting serine/threonine kinase 3; SNAP29: synaptosome associated protein 29; SNARE: soluble N-ethylmaleimide-sensitive factor attachment protein receptor; SQSTM1/p62: sequestosome 1; STK11/LKB1: serine/threonine kinase 11; STX7: syntaxin 7; STX17: syntaxin 17; TAX1BP1: Tax1 binding protein 1; TNF: tumor necrosis factor; ULK1: unc-51 like autophagy activating kinase 1; VAMP8: vesicle associated membrane protein 8; WT: wild-type.
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Affiliation(s)
- Wenxian Wu
- Institute of Molecular Medicine I, Medical Faculty, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Xiaojing Wang
- Institute of Molecular Medicine I, Medical Faculty, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Yadong Sun
- Institute of Molecular Medicine I, Medical Faculty, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Niklas Berleth
- Institute of Molecular Medicine I, Medical Faculty, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Jana Deitersen
- Institute of Molecular Medicine I, Medical Faculty, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - David Schlütermann
- Institute of Molecular Medicine I, Medical Faculty, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Fabian Stuhldreier
- Institute of Molecular Medicine I, Medical Faculty, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | | | - María José Mendiburo
- Institute of Molecular Medicine I, Medical Faculty, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Jan Cox
- Institute of Molecular Medicine I, Medical Faculty, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Christoph Peter
- Institute of Molecular Medicine I, Medical Faculty, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Ann Kathrin Bergmann
- Core Facility for Electron Microscopy, Medical Faculty, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Björn Stork
- Institute of Molecular Medicine I, Medical Faculty, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
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27
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Flinck M, Hagelund S, Gorbatenko A, Severin M, Pedraz-Cuesta E, Novak I, Stock C, Pedersen SF. The Vacuolar H + ATPase α3 Subunit Negatively Regulates Migration and Invasion of Human Pancreatic Ductal Adenocarcinoma Cells. Cells 2020; 9:E465. [PMID: 32085585 PMCID: PMC7072798 DOI: 10.3390/cells9020465] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Revised: 02/10/2020] [Accepted: 02/13/2020] [Indexed: 12/12/2022] Open
Abstract
Increased metabolic acid production and upregulation of net acid extrusion render pH homeostasis profoundly dysregulated in many cancers. Plasma membrane activity of vacuolar H+ ATPases (V-ATPases) has been implicated in acid extrusion and invasiveness of some cancers, yet often on the basis of unspecific inhibitors. Serving as a membrane anchor directing V-ATPase localization, the a subunit of the V0 domain of the V-ATPase (ATP6V0a1-4) is particularly interesting in this regard. Here, we map the regulation and roles of ATP6V0a3 in migration, invasion, and growth in pancreatic ductal adenocarcinoma (PDAC) cells. a3 mRNA and protein levels were upregulated in PDAC cell lines compared to non-cancer pancreatic epithelial cells. Under control conditions, a3 localization was mainly endo-/lysosomal, and its knockdown had no detectable effect on pHi regulation after acid loading. V-ATPase inhibition, but not a3 knockdown, increased HIF-1 expression and decreased proliferation and autophagic flux under both starved and non-starved conditions, and spheroid growth of PDAC cells was also unaffected by a3 knockdown. Strikingly, a3 knockdown increased migration and transwell invasion of Panc-1 and BxPC-3 PDAC cells, and increased gelatin degradation in BxPC-3 cells yet decreased it in Panc-1 cells. We conclude that in these PDAC cells, a3 is upregulated and negatively regulates migration and invasion, likely in part via effects on extracellular matrix degradation.
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Affiliation(s)
- Mette Flinck
- Section for Cell Biology and Physiology, Department of Biology, Faculty of Science, University of Copenhagen, DK-2100 Copenhagen, Denmark; (M.F.); (S.H.); (M.S.); (E.P.-C.); (I.N.)
| | - Sofie Hagelund
- Section for Cell Biology and Physiology, Department of Biology, Faculty of Science, University of Copenhagen, DK-2100 Copenhagen, Denmark; (M.F.); (S.H.); (M.S.); (E.P.-C.); (I.N.)
| | - Andrej Gorbatenko
- Department of Pathology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA;
| | - Marc Severin
- Section for Cell Biology and Physiology, Department of Biology, Faculty of Science, University of Copenhagen, DK-2100 Copenhagen, Denmark; (M.F.); (S.H.); (M.S.); (E.P.-C.); (I.N.)
| | - Elena Pedraz-Cuesta
- Section for Cell Biology and Physiology, Department of Biology, Faculty of Science, University of Copenhagen, DK-2100 Copenhagen, Denmark; (M.F.); (S.H.); (M.S.); (E.P.-C.); (I.N.)
| | - Ivana Novak
- Section for Cell Biology and Physiology, Department of Biology, Faculty of Science, University of Copenhagen, DK-2100 Copenhagen, Denmark; (M.F.); (S.H.); (M.S.); (E.P.-C.); (I.N.)
| | - Christian Stock
- Department of Gastroentero-, Hepato- and Endocrinology, Hannover Medical School, D-30625 Hannover, Germany;
| | - Stine Falsig Pedersen
- Section for Cell Biology and Physiology, Department of Biology, Faculty of Science, University of Copenhagen, DK-2100 Copenhagen, Denmark; (M.F.); (S.H.); (M.S.); (E.P.-C.); (I.N.)
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28
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Lystad AH, Simonsen A. Mechanisms and Pathophysiological Roles of the ATG8 Conjugation Machinery. Cells 2019; 8:E973. [PMID: 31450711 PMCID: PMC6769624 DOI: 10.3390/cells8090973] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 08/19/2019] [Accepted: 08/20/2019] [Indexed: 12/18/2022] Open
Abstract
Since their initial discovery around two decades ago, the yeast autophagy-related (Atg)8 protein and its mammalian homologues of the light chain 3 (LC3) and γ-aminobutyric acid receptor associated proteins (GABARAP) families have been key for the tremendous expansion of our knowledge about autophagy, a process in which cytoplasmic material become targeted for lysosomal degradation. These proteins are ubiquitin-like proteins that become directly conjugated to a lipid in the autophagy membrane upon induction of autophagy, thus providing a marker of the pathway, allowing studies of autophagosome biogenesis and maturation. Moreover, the ATG8 proteins function to recruit components of the core autophagy machinery as well as cargo for selective degradation. Importantly, comprehensive structural and biochemical in vitro studies of the machinery required for ATG8 protein lipidation, as well as their genetic manipulation in various model organisms, have provided novel insight into the molecular mechanisms and pathophysiological roles of the mATG8 proteins. Recently, it has become evident that the ATG8 proteins and their conjugation machinery are also involved in intracellular pathways and processes not related to autophagy. This review focuses on the molecular functions of ATG8 proteins and their conjugation machinery in autophagy and other pathways, as well as their links to disease.
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Affiliation(s)
- Alf Håkon Lystad
- Department of Molecular Medicine, Institute of Basic Medical Sciences and Centre for Cancer Cell Reprogramming, Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, 1112 Blindern, 0317 Oslo, Norway.
| | - Anne Simonsen
- Department of Molecular Medicine, Institute of Basic Medical Sciences and Centre for Cancer Cell Reprogramming, Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, 1112 Blindern, 0317 Oslo, Norway.
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29
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Liu Y, Luo X, Shan H, Fu Y, Gu Q, Zheng X, Dai Q, Xia F, Zheng Z, Liu P, Yin XM, Hong L, Li M. Niclosamide Triggers Non-Canonical LC3 Lipidation. Cells 2019; 8:cells8030248. [PMID: 30875964 PMCID: PMC6468753 DOI: 10.3390/cells8030248] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2019] [Revised: 03/07/2019] [Accepted: 03/12/2019] [Indexed: 01/19/2023] Open
Abstract
Autophagy is a highly- evolutionarily-conserved catabolic pathway activated by various cellular stresses. Recently, non-canonical autophagy (NCA), which does not require all of the ATG proteins to form autophagosome or autophagosome-like structures, has been found in various conditions. Moreover, mounting evidence has indicated that non-canonical LC3 lipidation (NCLL) may reflect NCA. We and others have reported that niclosamide (Nic), an anti-helminthic drug approved by the Food and Drug Administration, could induce canonical autophagy via a feedback downregulation of mTOR complex 1. In this study, we found that Nic could also induce NCLL, which is independent of the ULK1 complex and Beclin 1 complex, but dependent on ubiquitin-like conjugation systems. Although bafilomycin A1 and concanamycin A, two known V-ATPase inhibitors, significantly inhibited Nic-induced NCLL, Nic-induced NCLL was demonstrated to be independent of V-ATPase. In addition, the Golgi complex and vimentin were involved in Nic-induced NCLL, which might be a platform or membrane source for Nic-induced LC3-positive structures. These results would be helpful to broaden our understanding of the working mechanisms of Nic and evaluate its pharmacological activities in diseases.
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Affiliation(s)
- Yajun Liu
- School of Pharmaceutical Sciences, Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, National and Local United Engineering Lab of Druggability and New Drugs Evaluation, Sun Yat-Sen University, Guangzhou, Guangdong 510006, China.
| | - Xia Luo
- School of Pharmaceutical Sciences, Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, National and Local United Engineering Lab of Druggability and New Drugs Evaluation, Sun Yat-Sen University, Guangzhou, Guangdong 510006, China.
| | - Hao Shan
- School of Pharmaceutical Sciences, Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, National and Local United Engineering Lab of Druggability and New Drugs Evaluation, Sun Yat-Sen University, Guangzhou, Guangdong 510006, China.
| | - Yuanyuan Fu
- School of Pharmaceutical Sciences, Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, National and Local United Engineering Lab of Druggability and New Drugs Evaluation, Sun Yat-Sen University, Guangzhou, Guangdong 510006, China.
| | - Qianqian Gu
- School of Pharmaceutical Sciences, Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, National and Local United Engineering Lab of Druggability and New Drugs Evaluation, Sun Yat-Sen University, Guangzhou, Guangdong 510006, China.
| | - Xueping Zheng
- School of Pharmaceutical Sciences, Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, National and Local United Engineering Lab of Druggability and New Drugs Evaluation, Sun Yat-Sen University, Guangzhou, Guangdong 510006, China.
| | - Qi Dai
- School of Pharmaceutical Sciences, Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, National and Local United Engineering Lab of Druggability and New Drugs Evaluation, Sun Yat-Sen University, Guangzhou, Guangdong 510006, China.
| | - Fan Xia
- School of Pharmaceutical Sciences, Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, National and Local United Engineering Lab of Druggability and New Drugs Evaluation, Sun Yat-Sen University, Guangzhou, Guangdong 510006, China.
| | - Zhihua Zheng
- School of Pharmaceutical Sciences, Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, National and Local United Engineering Lab of Druggability and New Drugs Evaluation, Sun Yat-Sen University, Guangzhou, Guangdong 510006, China.
| | - Peiqing Liu
- School of Pharmaceutical Sciences, Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, National and Local United Engineering Lab of Druggability and New Drugs Evaluation, Sun Yat-Sen University, Guangzhou, Guangdong 510006, China.
| | - Xiao-Ming Yin
- Department of Pathology and Laboratory Medicine, Indiana University School of Medicine, Indianapolis, IN 46202, USA.
| | - Liang Hong
- School of Pharmaceutical Sciences, Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, National and Local United Engineering Lab of Druggability and New Drugs Evaluation, Sun Yat-Sen University, Guangzhou, Guangdong 510006, China.
| | - Min Li
- School of Pharmaceutical Sciences, Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, National and Local United Engineering Lab of Druggability and New Drugs Evaluation, Sun Yat-Sen University, Guangzhou, Guangdong 510006, China.
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30
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Lystad AH, Carlsson SR, de la Ballina LR, Kauffman KJ, Nag S, Yoshimori T, Melia TJ, Simonsen A. Distinct functions of ATG16L1 isoforms in membrane binding and LC3B lipidation in autophagy-related processes. Nat Cell Biol 2019; 21:372-383. [PMID: 30778222 DOI: 10.1038/s41556-019-0274-9] [Citation(s) in RCA: 120] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Accepted: 01/03/2019] [Indexed: 02/07/2023]
Abstract
Covalent modification of LC3 and GABARAP proteins to phosphatidylethanolamine in the double-membrane phagophore is a key event in the early phase of macroautophagy, but can also occur on single-membrane structures. In both cases this involves transfer of LC3/GABARAP from ATG3 to phosphatidylethanolamine at the target membrane. Here we have purified the full-length human ATG12-5-ATG16L1 complex and show its essential role in LC3B/GABARAP lipidation in vitro. We have identified two functionally distinct membrane-binding regions in ATG16L1. An N-terminal membrane-binding amphipathic helix is required for LC3B lipidation under all conditions tested. By contrast, the C-terminal membrane-binding region is dispensable for canonical autophagy but essential for VPS34-independent LC3B lipidation at perturbed endosomes. We further show that the ATG16L1 C-terminus can compensate for WIPI2 depletion to sustain lipidation during starvation. This C-terminal membrane-binding region is present only in the β-isoform of ATG16L1, showing that ATG16L1 isoforms mechanistically distinguish between different LC3B lipidation mechanisms under different cellular conditions.
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Affiliation(s)
- Alf Håkon Lystad
- Department of Molecular Medicine, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, Oslo, Norway. .,Centre for Cancer Cell Reprogramming, Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Oslo, Norway.
| | - Sven R Carlsson
- Department of Medical Biochemistry and Biophysics, University of Umeå, Umeå, Sweden.
| | - Laura R de la Ballina
- Department of Molecular Medicine, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, Oslo, Norway.,Centre for Cancer Cell Reprogramming, Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Oslo, Norway
| | - Karlina J Kauffman
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT, USA
| | - Shanta Nag
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT, USA
| | - Tamotsu Yoshimori
- Department of Genetics, Osaka University Graduate School of Medicine, Suita, Japan
| | - Thomas J Melia
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT, USA
| | - Anne Simonsen
- Department of Molecular Medicine, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, Oslo, Norway. .,Centre for Cancer Cell Reprogramming, Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Oslo, Norway.
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31
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Yuan Q, Li Y, Li J, Bian X, Long F, Duan R, Ma X, Gao F, Gao S, Wei S, Li X, Sun W, Liu Q. WDFY4 Is Involved in Symptoms of Systemic Lupus Erythematosus by Modulating B Cell Fate via Noncanonical Autophagy. THE JOURNAL OF IMMUNOLOGY 2018; 201:2570-2578. [PMID: 30257884 DOI: 10.4049/jimmunol.1800399] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Accepted: 08/23/2018] [Indexed: 12/31/2022]
Abstract
Genome-wide association studies have recently illuminated that WDFY4 is genetically associated with systemic lupus erythematosus (SLE) susceptibility in various ethnic groups. Despite strong genetic evidence suggesting a role of WDFY4 in SLE pathogenesis, its functional relevance is largely unknown. In this study, we generated Wdfy4 B lymphocyte conditional knockout (Wdfy4-CKO) mice and found that loss of Wdfy4 led to a decrease in number of total B cells and several subpopulations of B cells in the periphery and a defect in the transition from the pro- to pre-B cell stage in bone marrow. Also, Wdfy4-CKO mice showed impaired Ab responses as compared with controls when challenged with Ag. SLE phenotypes were effectively alleviated in Wdfy4-CKO mice, with significantly diminished pristane-elicited production of autoantibodies and glomerulonephritis. Genetic silencing of WDFY4 in B cells increased lipidation of LC3 independent of p62 and Beclin1, which are essential proteins of canonical autophagy. Our in vivo and in vitro data suggest that WDFY4 facilitates noncanonical autophagic activity. Our findings provide a novel functional link underlying the mechanism of SLE in which WDFY4 influences B cell fate via noncanonical autophagy.
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Affiliation(s)
- Qianqian Yuan
- Key Laboratory for Experimental Teratology of the Ministry of Education, Shandong University School of Medicine, Jinan, Shandong 250012, China.,Department of Medical Genetics, Shandong University School of Medicine, Jinan, Shandong 250012, China; and
| | - Yan Li
- Key Laboratory for Experimental Teratology of the Ministry of Education, Shandong University School of Medicine, Jinan, Shandong 250012, China.,Department of Medical Genetics, Shandong University School of Medicine, Jinan, Shandong 250012, China; and
| | - Jiangxia Li
- Key Laboratory for Experimental Teratology of the Ministry of Education, Shandong University School of Medicine, Jinan, Shandong 250012, China.,Department of Medical Genetics, Shandong University School of Medicine, Jinan, Shandong 250012, China; and
| | - Xianli Bian
- Key Laboratory for Experimental Teratology of the Ministry of Education, Shandong University School of Medicine, Jinan, Shandong 250012, China.,Department of Medical Genetics, Shandong University School of Medicine, Jinan, Shandong 250012, China; and
| | - Feng Long
- Key Laboratory for Experimental Teratology of the Ministry of Education, Shandong University School of Medicine, Jinan, Shandong 250012, China.,Department of Medical Genetics, Shandong University School of Medicine, Jinan, Shandong 250012, China; and
| | - Ruonan Duan
- Key Laboratory for Experimental Teratology of the Ministry of Education, Shandong University School of Medicine, Jinan, Shandong 250012, China.,Department of Medical Genetics, Shandong University School of Medicine, Jinan, Shandong 250012, China; and
| | - Xiaochun Ma
- Department of Cardiovascular Surgery, Shandong Provincial Hospital Affiliated to Shandong University, Shandong 250021, China
| | - Fei Gao
- Key Laboratory for Experimental Teratology of the Ministry of Education, Shandong University School of Medicine, Jinan, Shandong 250012, China.,Department of Medical Genetics, Shandong University School of Medicine, Jinan, Shandong 250012, China; and
| | - Shang Gao
- Key Laboratory for Experimental Teratology of the Ministry of Education, Shandong University School of Medicine, Jinan, Shandong 250012, China.,Department of Medical Genetics, Shandong University School of Medicine, Jinan, Shandong 250012, China; and
| | - Shijun Wei
- Key Laboratory for Experimental Teratology of the Ministry of Education, Shandong University School of Medicine, Jinan, Shandong 250012, China.,Department of Medical Genetics, Shandong University School of Medicine, Jinan, Shandong 250012, China; and
| | - Xi Li
- Key Laboratory for Experimental Teratology of the Ministry of Education, Shandong University School of Medicine, Jinan, Shandong 250012, China.,Department of Medical Genetics, Shandong University School of Medicine, Jinan, Shandong 250012, China; and
| | - Wenjie Sun
- Key Laboratory for Experimental Teratology of the Ministry of Education, Shandong University School of Medicine, Jinan, Shandong 250012, China.,Department of Medical Genetics, Shandong University School of Medicine, Jinan, Shandong 250012, China; and
| | - Qiji Liu
- Key Laboratory for Experimental Teratology of the Ministry of Education, Shandong University School of Medicine, Jinan, Shandong 250012, China; .,Department of Medical Genetics, Shandong University School of Medicine, Jinan, Shandong 250012, China; and
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32
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Fu Y, Hong L, Xu J, Zhong G, Gu Q, Gu Q, Guan Y, Zheng X, Dai Q, Luo X, Liu C, Huang Z, Yin XM, Liu P, Li M. Discovery of a small molecule targeting autophagy via ATG4B inhibition and cell death of colorectal cancer cells in vitro and in vivo. Autophagy 2018; 15:295-311. [PMID: 30176161 DOI: 10.1080/15548627.2018.1517073] [Citation(s) in RCA: 99] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Human Atg4 homologs are cysteine proteases, which play key roles in the macroautophagy/autophagy process by cleaving Atg8 homologs for conjugation to lipid membranes and for deconjugation of Atg8 homologs from membranes. Expression of ATG4B is significantly increased in colorectal cancer cells compared to normal cells, suggesting that ATG4B may be important for cancer biology. Inhibition of ATG4B may reduce the autophagy activity, thereby sensitizing cancer cells to therapeutic agents. Thus, developing specific and potent ATG4B inhibitors for research as well as for potential therapeutic uses is highly needed. In this study, we integrated in silico screening and in vitro assays to discover a potent ATG4B inhibitor, named S130, from a noncommercial library. This chemical binds to ATG4B with strong affinity and specifically suppresses the activity of ATG4B but not other proteases. S130 did not cause the impairment of autophagosome fusion, nor did it result in the dysfunction of lysosomes. Instead, S130 might attenuate the delipidation of LC3-II on the autolysosomes to suppress the recycling of LC3-I, which normally occurs after LC3-II cleavage by ATG4B. Intriguingly, S130 induced cell death, which was accompanied with autophagy stress and could be further exacerbated by nutrient deprivation. Such cytotoxicity could be partially reversed by enhancing ATG4B activity. Finally, we found that S130 was distributed in tumor tissues in vivo and was also effective in arresting the growth of colorectal cancer cells. Thus, this study indicates that ATG4B is a potential anticancer target and S130 might be a novel small-molecule candidate for future cancer therapy.
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Affiliation(s)
- Yuanyuan Fu
- a School of Pharmaceutical Sciences, National and Local United Engineering Lab of Druggability and New Drugs Evaluation, Guangdong Provincial Key Laboratory of New Drug Design and Evaluation , Sun Yat-Sen University , Guangzhou , Guangdong , China
| | - Liang Hong
- a School of Pharmaceutical Sciences, National and Local United Engineering Lab of Druggability and New Drugs Evaluation, Guangdong Provincial Key Laboratory of New Drug Design and Evaluation , Sun Yat-Sen University , Guangzhou , Guangdong , China
| | - Jiecheng Xu
- a School of Pharmaceutical Sciences, National and Local United Engineering Lab of Druggability and New Drugs Evaluation, Guangdong Provincial Key Laboratory of New Drug Design and Evaluation , Sun Yat-Sen University , Guangzhou , Guangdong , China
| | - Guoping Zhong
- a School of Pharmaceutical Sciences, National and Local United Engineering Lab of Druggability and New Drugs Evaluation, Guangdong Provincial Key Laboratory of New Drug Design and Evaluation , Sun Yat-Sen University , Guangzhou , Guangdong , China
| | - Qiong Gu
- a School of Pharmaceutical Sciences, National and Local United Engineering Lab of Druggability and New Drugs Evaluation, Guangdong Provincial Key Laboratory of New Drug Design and Evaluation , Sun Yat-Sen University , Guangzhou , Guangdong , China
| | - Qianqian Gu
- a School of Pharmaceutical Sciences, National and Local United Engineering Lab of Druggability and New Drugs Evaluation, Guangdong Provincial Key Laboratory of New Drug Design and Evaluation , Sun Yat-Sen University , Guangzhou , Guangdong , China
| | - Yanping Guan
- a School of Pharmaceutical Sciences, National and Local United Engineering Lab of Druggability and New Drugs Evaluation, Guangdong Provincial Key Laboratory of New Drug Design and Evaluation , Sun Yat-Sen University , Guangzhou , Guangdong , China
| | - Xueping Zheng
- a School of Pharmaceutical Sciences, National and Local United Engineering Lab of Druggability and New Drugs Evaluation, Guangdong Provincial Key Laboratory of New Drug Design and Evaluation , Sun Yat-Sen University , Guangzhou , Guangdong , China
| | - Qi Dai
- a School of Pharmaceutical Sciences, National and Local United Engineering Lab of Druggability and New Drugs Evaluation, Guangdong Provincial Key Laboratory of New Drug Design and Evaluation , Sun Yat-Sen University , Guangzhou , Guangdong , China
| | - Xia Luo
- a School of Pharmaceutical Sciences, National and Local United Engineering Lab of Druggability and New Drugs Evaluation, Guangdong Provincial Key Laboratory of New Drug Design and Evaluation , Sun Yat-Sen University , Guangzhou , Guangdong , China
| | - Cui Liu
- a School of Pharmaceutical Sciences, National and Local United Engineering Lab of Druggability and New Drugs Evaluation, Guangdong Provincial Key Laboratory of New Drug Design and Evaluation , Sun Yat-Sen University , Guangzhou , Guangdong , China
| | - Zhiying Huang
- a School of Pharmaceutical Sciences, National and Local United Engineering Lab of Druggability and New Drugs Evaluation, Guangdong Provincial Key Laboratory of New Drug Design and Evaluation , Sun Yat-Sen University , Guangzhou , Guangdong , China
| | - Xiao-Ming Yin
- b Department of Pathology and Laboratory Medicine , Indiana University School of Medicine , Indianapolis , IN , USA
| | - Peiqing Liu
- a School of Pharmaceutical Sciences, National and Local United Engineering Lab of Druggability and New Drugs Evaluation, Guangdong Provincial Key Laboratory of New Drug Design and Evaluation , Sun Yat-Sen University , Guangzhou , Guangdong , China
| | - Min Li
- a School of Pharmaceutical Sciences, National and Local United Engineering Lab of Druggability and New Drugs Evaluation, Guangdong Provincial Key Laboratory of New Drug Design and Evaluation , Sun Yat-Sen University , Guangzhou , Guangdong , China
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Whitton B, Okamoto H, Packham G, Crabb SJ. Vacuolar ATPase as a potential therapeutic target and mediator of treatment resistance in cancer. Cancer Med 2018; 7:3800-3811. [PMID: 29926527 PMCID: PMC6089187 DOI: 10.1002/cam4.1594] [Citation(s) in RCA: 71] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2018] [Revised: 05/07/2018] [Accepted: 05/08/2018] [Indexed: 01/10/2023] Open
Abstract
Vacuolar ATPase (V-ATPase) is an ATP-dependent H+ -transporter that pumps protons across intracellular and plasma membranes. It consists of a large multi-subunit protein complex and influences a wide range of cellular processes. This review focuses on emerging evidence for the roles for V-ATPase in cancer. This includes how V-ATPase dysregulation contributes to cancer growth, metastasis, invasion and proliferation, and the potential link between V-ATPase and the development of drug resistance.
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Affiliation(s)
- Bradleigh Whitton
- Southampton Cancer Research UK CentreUniversity of SouthamptonSouthamptonUK
- Biological SciencesFaculty of Natural and Environmental SciencesUniversity of SouthamptonSouthamptonUK
| | - Haruko Okamoto
- Biological SciencesFaculty of Natural and Environmental SciencesUniversity of SouthamptonSouthamptonUK
| | - Graham Packham
- Southampton Cancer Research UK CentreUniversity of SouthamptonSouthamptonUK
| | - Simon J. Crabb
- Southampton Cancer Research UK CentreUniversity of SouthamptonSouthamptonUK
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Abstract
Macroautophagy (herein referred to as autophagy) is a highly conserved stress response that engulfs damaged proteins, lipids, and/or organelles within double-membrane vesicles called autophagosomes for lysosomal degradation. Dysregulated autophagy is a hallmark of cancer; and thus, there is great interest in modulating autophagy for cancer therapy. Sphingolipids regulate each step of autophagosome biogenesis with roles for sphingolipid metabolites and enzymes spanning from the initial step of de novo ceramide synthesis to the sphingosine-1-phosphate lyase 1-mediated exit from the sphingolipid pathway. Notably, sphingolipid metabolism occurs at several of the organelles that contribute to autophagosome biogenesis to suggest that local changes in sphingolipids may regulate autophagy. As sphingolipid metabolism is frequently dysregulated in cancer, a molecular understanding of sphingolipids in stress-induced autophagy may provide insight into the mechanisms driving tumor development and progression. On the contrary, modulation of sphingolipid metabolites and/or enzymes can induce autophagy-dependent cell death for cancer therapy. This chapter will overview the major steps in mammalian autophagy, discuss the regulation of each step by sphingolipid metabolites, and describe the functions of sphingolipid-mediated autophagy in cancer. While our understanding of the signaling and biophysical properties of sphingolipids in autophagy remains in its infancy, the unique cross talk between the two pathways is an exciting area for further development, particularly in the context of cancer therapy.
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Affiliation(s)
- Megan M Young
- Department of Pediatrics, Pennsylvania State University College of Medicine, Hershey, PA, United States
| | - Hong-Gang Wang
- Department of Pediatrics, Pennsylvania State University College of Medicine, Hershey, PA, United States
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Wallot-Hieke N, Verma N, Schlütermann D, Berleth N, Deitersen J, Böhler P, Stuhldreier F, Wu W, Seggewiß S, Peter C, Gohlke H, Mizushima N, Stork B. Systematic analysis of ATG13 domain requirements for autophagy induction. Autophagy 2018; 14:743-763. [PMID: 29173006 PMCID: PMC6070014 DOI: 10.1080/15548627.2017.1387342] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Macroautophagy/autophagy is an evolutionarily conserved cellular process whose induction is regulated by the ULK1 protein kinase complex. The subunit ATG13 functions as an adaptor protein by recruiting ULK1, RB1CC1 and ATG101 to a core ULK1 complex. Furthermore, ATG13 directly binds both phospholipids and members of the Atg8 family. The central involvement of ATG13 in complex formation makes it an attractive target for autophagy regulation. Here, we analyzed known interactions of ATG13 with proteins and lipids for their potential modulation of ULK1 complex formation and autophagy induction. Targeting the ATG101-ATG13 interaction showed the strongest autophagy-inhibitory effect, whereas the inhibition of binding to ULK1 or RB1CC1 had only minor effects, emphasizing that mutations interfering with ULK1 complex assembly do not necessarily result in a blockade of autophagy. Furthermore, inhibition of ATG13 binding to phospholipids or Atg8 proteins had only mild effects on autophagy. Generally, the observed phenotypes were more severe when autophagy was induced by MTORC1/2 inhibition compared to amino acid starvation. Collectively, these data establish the interaction between ATG13 and ATG101 as a promising target in disease-settings where the inhibition of autophagy is desired.
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Affiliation(s)
- Nora Wallot-Hieke
- a Institute of Molecular Medicine I, Medical Faculty , Heinrich Heine University Düsseldorf , Düsseldorf , Germany
| | - Neha Verma
- b Institute for Pharmaceutical and Medicinal Chemistry, Faculty of Mathematics and Natural Sciences , Heinrich Heine University Düsseldorf , Düsseldorf , Germany
| | - David Schlütermann
- a Institute of Molecular Medicine I, Medical Faculty , Heinrich Heine University Düsseldorf , Düsseldorf , Germany
| | - Niklas Berleth
- a Institute of Molecular Medicine I, Medical Faculty , Heinrich Heine University Düsseldorf , Düsseldorf , Germany
| | - Jana Deitersen
- a Institute of Molecular Medicine I, Medical Faculty , Heinrich Heine University Düsseldorf , Düsseldorf , Germany
| | - Philip Böhler
- a Institute of Molecular Medicine I, Medical Faculty , Heinrich Heine University Düsseldorf , Düsseldorf , Germany
| | - Fabian Stuhldreier
- a Institute of Molecular Medicine I, Medical Faculty , Heinrich Heine University Düsseldorf , Düsseldorf , Germany
| | - Wenxian Wu
- a Institute of Molecular Medicine I, Medical Faculty , Heinrich Heine University Düsseldorf , Düsseldorf , Germany
| | - Sabine Seggewiß
- a Institute of Molecular Medicine I, Medical Faculty , Heinrich Heine University Düsseldorf , Düsseldorf , Germany
| | - Christoph Peter
- a Institute of Molecular Medicine I, Medical Faculty , Heinrich Heine University Düsseldorf , Düsseldorf , Germany
| | - Holger Gohlke
- b Institute for Pharmaceutical and Medicinal Chemistry, Faculty of Mathematics and Natural Sciences , Heinrich Heine University Düsseldorf , Düsseldorf , Germany
| | - Noboru Mizushima
- c Department of Biochemistry and Molecular Biology, Graduate School and Faculty of Medicine , The University of Tokyo , Tokyo , Japan
| | - Björn Stork
- a Institute of Molecular Medicine I, Medical Faculty , Heinrich Heine University Düsseldorf , Düsseldorf , Germany
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Chu J, Fu Y, Xu J, Zheng X, Gu Q, Luo X, Dai Q, Zhang S, Liu P, Hong L, Li M. ATG4B inhibitor FMK-9a induces autophagy independent on its enzyme inhibition. Arch Biochem Biophys 2018; 644:29-36. [PMID: 29510087 DOI: 10.1016/j.abb.2018.03.001] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Revised: 02/07/2018] [Accepted: 03/02/2018] [Indexed: 02/07/2023]
Abstract
Atg4 is essential for autophagosome formation and Atg8 recycle with the function of processing the precursor and the lipidated Atg8-family proteins. Abnormal autophagic activity is involved in a variety of pathophysiological diseases and ATG4B is of interest as a potential therapeutic target due to its key roles in autophagy process. So ATG4B inhibitors are highly needed. FMK-9a is the most potent inhibitor reported so far. In this study, we confirmed FMK-9a could suppress ATG4B activity in vitro and in cells, with an IC50 of 260 nM. Besides, FMK-9a could also attenuate the process of cleavage of pro-LC3 and the delipidation of LC3-PE. Importantly, FMK-9a could induce autophagy both in HeLa and MEF cells regardless of its inhibition on ATG4B activity. Moreover, FMK-9a induced autophagy required FIP200 and ATG5. In conclusion, we demonstrated that ATG4B inhibitor FMK-9a induces autophagy independent on its enzyme inhibition. Thus, FMK-9a may plays multiple roles in autophagy process and cannot simply take it as an ATG4B inhibitor.
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Affiliation(s)
- Jiaqi Chu
- School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, Guangdong, 510006, China
| | - Yuanyuan Fu
- School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, Guangdong, 510006, China
| | - Jiecheng Xu
- School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, Guangdong, 510006, China
| | - Xueping Zheng
- School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, Guangdong, 510006, China
| | - Qianqian Gu
- School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, Guangdong, 510006, China
| | - Xia Luo
- School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, Guangdong, 510006, China
| | - Qi Dai
- School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, Guangdong, 510006, China
| | - Shuxian Zhang
- School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, Guangdong, 510006, China
| | - Peiqing Liu
- School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, Guangdong, 510006, China
| | - Liang Hong
- School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, Guangdong, 510006, China.
| | - Min Li
- School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, Guangdong, 510006, China.
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Signalome-wide RNAi screen identifies GBA1 as a positive mediator of autophagic cell death. Cell Death Differ 2017; 24:1288-1302. [PMID: 28574511 PMCID: PMC5520177 DOI: 10.1038/cdd.2017.80] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Revised: 04/12/2017] [Accepted: 04/12/2017] [Indexed: 12/28/2022] Open
Abstract
Activating alternative cell death pathways, including autophagic cell death, is a promising direction to overcome the apoptosis resistance observed in various cancers. Yet, whether autophagy acts as a death mechanism by over consumption of intracellular components is still controversial and remains undefined at the ultrastructural and the mechanistic levels. Here we identified conditions under which resveratrol-treated A549 lung cancer cells die by a mechanism that fulfills the previous definition of autophagic cell death. The cells displayed a strong and sustained induction of autophagic flux, cell death was prevented by knocking down autophagic genes and death occurred in the absence of apoptotic or necroptotic pathway activation. Detailed ultrastructural characterization revealed additional critical events, including a continuous increase over time in the number of autophagic vacuoles, in particular autolysosomes, occupying most of the cytoplasm at terminal stages. This was followed by loss of organelles, disruption of intracellular membranes including the swelling of perinuclear space and, occasionally, a unique type of nuclear shedding. A signalome-wide shRNA-based viability screen was applied to identify positive mediators of this type of autophagic cell death. One top hit was GBA1, the Gaucher disease-associated gene, which encodes glucocerebrosidase, an enzyme that metabolizes glucosylceramide to ceramide and glucose. Interestingly, glucocerebrosidase expression levels and activity were elevated, concomitantly with increased intracellular ceramide levels, both of which correlated in time with the appearance of the unique death characteristics. Transfection with siGBA1 attenuated the increase in glucocerebrosidase activity and the intracellular ceramide levels. Most importantly, GBA1 knockdown prevented the strong increase in LC3 lipidation, and many of the ultrastructural changes characteristic of this type of autophagic cell death, including a significant decrease in cytoplasmic area occupied by autophagic vacuoles. Together, these findings highlight the critical role of GBA1 in mediating enhanced self-consumption of intracellular components and endomembranes, leading to autophagic cell death.
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