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Shariq M, Khan MF, Raj R, Ahsan N, Kumar P. PRKAA2, MTOR, and TFEB in the regulation of lysosomal damage response and autophagy. J Mol Med (Berl) 2024; 102:287-311. [PMID: 38183492 DOI: 10.1007/s00109-023-02411-7] [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: 05/08/2023] [Revised: 12/07/2023] [Accepted: 12/18/2023] [Indexed: 01/08/2024]
Abstract
Lysosomes function as critical signaling hubs that govern essential enzyme complexes. LGALS proteins (LGALS3, LGALS8, and LGALS9) are integral to the endomembrane damage response. If ESCRT fails to rectify damage, LGALS-mediated ubiquitination occurs, recruiting autophagy receptors (CALCOCO2, TRIM16, and SQSTM1) and VCP/p97 complex containing UBXN6, PLAA, and YOD1, initiating selective autophagy. Lysosome replenishment through biogenesis is regulated by TFEB. LGALS3 interacts with TFRC and TRIM16, aiding ESCRT-mediated repair and autophagy-mediated removal of damaged lysosomes. LGALS8 inhibits MTOR and activates TFEB for ATG and lysosomal gene transcription. LGALS9 inhibits USP9X, activates PRKAA2, MAP3K7, ubiquitination, and autophagy. Conjugation of ATG8 to single membranes (CASM) initiates damage repair mediated by ATP6V1A, ATG16L1, ATG12, ATG5, ATG3, and TECPR1. ATG8ylation or CASM activates the MERIT system (ESCRT-mediated repair, autophagy-mediated clearance, MCOLN1 activation, Ca2+ release, RRAG-GTPase regulation, MTOR modulation, TFEB activation, and activation of GTPase IRGM). Annexins ANAX1 and ANAX2 aid damage repair. Stress granules stabilize damaged membranes, recruiting FLCN-FNIP1/2, G3BP1, and NUFIP1 to inhibit MTOR and activate TFEB. Lysosomes coordinate the synergistic response to endomembrane damage and are vital for innate and adaptive immunity. Future research should unveil the collaborative actions of ATG proteins, LGALSs, TRIMs, autophagy receptors, and lysosomal proteins in lysosomal damage response.
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Affiliation(s)
- Mohd Shariq
- Quantlase Imaging Laboratory, Quantlase Lab LLC, Unit 1-8, Masdar City, Abu Dhabi, UAE.
| | - Mohammad Firoz Khan
- Quantlase Imaging Laboratory, Quantlase Lab LLC, Unit 1-8, Masdar City, Abu Dhabi, UAE.
| | - Reshmi Raj
- Quantlase Imaging Laboratory, Quantlase Lab LLC, Unit 1-8, Masdar City, Abu Dhabi, UAE
| | - Nuzhat Ahsan
- Quantlase Imaging Laboratory, Quantlase Lab LLC, Unit 1-8, Masdar City, Abu Dhabi, UAE
| | - Pramod Kumar
- Quantlase Imaging Laboratory, Quantlase Lab LLC, Unit 1-8, Masdar City, Abu Dhabi, UAE
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2
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Xiang H, Zhou M, Li Y, Zhou L, Wang R. Drug discovery by targeting the protein-protein interactions involved in autophagy. Acta Pharm Sin B 2023; 13:4373-4390. [PMID: 37969735 PMCID: PMC10638514 DOI: 10.1016/j.apsb.2023.07.016] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2023] [Revised: 05/31/2023] [Accepted: 07/10/2023] [Indexed: 11/17/2023] Open
Abstract
Autophagy is a cellular process in which proteins and organelles are engulfed in autophagosomal vesicles and transported to the lysosome/vacuole for degradation. Protein-protein interactions (PPIs) play a crucial role at many stages of autophagy, which present formidable but attainable targets for autophagy regulation. Moreover, selective regulation of PPIs tends to have a lower risk in causing undesired off-target effects in the context of a complicated biological network. Thus, small-molecule regulators, including peptides and peptidomimetics, targeting the critical PPIs involved in autophagy provide a new opportunity for innovative drug discovery. This article provides general background knowledge of the critical PPIs involved in autophagy and reviews a range of successful attempts on discovering regulators targeting those PPIs. Successful strategies and existing limitations in this field are also discussed.
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Affiliation(s)
- Honggang Xiang
- Department of Medicinal Chemistry, School of Pharmacy, Fudan University, Shanghai 201203, China
| | - Mi Zhou
- Department of Medicinal Chemistry, School of Pharmacy, Fudan University, Shanghai 201203, China
| | - Yan Li
- Department of Medicinal Chemistry, School of Pharmacy, Fudan University, Shanghai 201203, China
| | - Lu Zhou
- Department of Medicinal Chemistry, School of Pharmacy, Fudan University, Shanghai 201203, China
| | - Renxiao Wang
- Department of Medicinal Chemistry, School of Pharmacy, Fudan University, Shanghai 201203, China
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3
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Choi HS, Bjornson M, Liang J, Wang J, Ke H, Hur M, De Souza A, Kumar KS, Mortimer JC, Dehesh K. COG-imposed Golgi functional integrity determines the onset of dark-induced senescence. NATURE PLANTS 2023; 9:1890-1901. [PMID: 37884654 DOI: 10.1038/s41477-023-01545-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Accepted: 09/18/2023] [Indexed: 10/28/2023]
Abstract
Plant survival depends on dynamic stress-response pathways in changing environments. To uncover pathway components, we screened an ethyl methanesulfonate-mutagenized transgenic line containing a stress-inducible luciferase construct and isolated a constitutive expression mutant. The mutant is the result of an amino acid substitution in the seventh subunit of the hetero-octameric conserved oligomeric Golgi (COG) complex of Arabidopsis thaliana. Complementation studies verified the Golgi localization of cog7, and stress tests established accelerated dark-induced carbon deprivation/senescence of the mutant compared with wild-type plants. Multiomics and biochemical analyses revealed accelerated induction of protein ubiquitination and autophagy, and a counterintuitive increased protein N-glycosylation in senescencing cog7 relative to wild-type. A revertant screen using the overexpressor (FOX)-hunting system established partial, but notable rescue of cog7 phenotypes by COG5 overexpression, and conversely premature senescence in reduced COG5 expressing lines. These findings identify COG-imposed Golgi functional integrity as a main player in ensuring cellular survival under energy-limiting conditions.
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Affiliation(s)
- Hee-Seung Choi
- Institute for Integrative Genome Biology and Department of Botany and Plant Sciences, University of California, Riverside, CA, USA
| | - Marta Bjornson
- Department of Plant Sciences, University of California, Davis, CA, USA
| | - Jiubo Liang
- Institute for Integrative Genome Biology and Department of Botany and Plant Sciences, University of California, Riverside, CA, USA
| | - Jinzheng Wang
- Institute for Integrative Genome Biology and Department of Botany and Plant Sciences, University of California, Riverside, CA, USA
| | - Haiyan Ke
- Institute for Integrative Genome Biology and Department of Botany and Plant Sciences, University of California, Riverside, CA, USA
| | - Manhoi Hur
- Institute for Integrative Genome Biology and Department of Botany and Plant Sciences, University of California, Riverside, CA, USA
| | - Amancio De Souza
- Institute for Integrative Genome Biology and Department of Botany and Plant Sciences, University of California, Riverside, CA, USA
| | | | - Jenny C Mortimer
- Lawrence Berkeley National Lab, Joint BioEnergy Institute, Emeryville, CA, USA
- School of Agriculture Food and Wine & Waite Research Institute, University of Adelaide, Adelaide, South Australia, Australia
| | - Katayoon Dehesh
- Institute for Integrative Genome Biology and Department of Botany and Plant Sciences, University of California, Riverside, CA, USA.
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4
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Zhao W, Wang L, Li L, Zhou T, Yan F, Zhang H, Zhu Y, Andika IB, Sun L. Coat protein of rice stripe virus enhances autophagy activity through interaction with cytosolic glyceraldehyde-3-phosphate dehydrogenases, a negative regulator of plant autophagy. STRESS BIOLOGY 2023; 3:3. [PMID: 37676568 PMCID: PMC10441990 DOI: 10.1007/s44154-023-00084-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Accepted: 02/28/2023] [Indexed: 09/08/2023]
Abstract
Viral infection commonly induces autophagy, leading to antiviral responses or conversely, promoting viral infection or replication. In this study, using the experimental plant Nicotiana benthamiana, we demonstrated that the rice stripe virus (RSV) coat protein (CP) enhanced autophagic activity through interaction with cytosolic glyceraldehyde-3-phosphate dehydrogenase 2 (GAPC2), a negative regulator of plant autophagy that binds to an autophagy key factor, autophagy-related protein 3 (ATG3). Competitive pull-down and co-immunoprecipitation (Co-IP)assays showed that RSV CP activated autophagy by disrupting the interaction between GAPC2 and ATG3. An RSV CP mutant that was unable to bind GAPC2 failed to disrupt the interaction between GAPC2 and ATG3 and therefore lost its ability to induce autophagy. RSV CP enhanced the autophagic degradation of a viral movement protein (MP) encoded by a heterologous virus, citrus leaf blotch virus (CLBV). However, the autophagic degradation of RSV-encoded MP and RNA-silencing suppressor (NS3) proteins was inhibited in the presence of CP, suggesting that RSV CP can protect MP and NS3 against autophagic degradation. Moreover, in the presence of MP, RSV CP could induce the autophagic degradation of a remorin protein (NbREM1), which negatively regulates RSV infection through the inhibition of viral cell-to-cell movement. Overall, our results suggest that RSV CP induces a selective autophagy to suppress the antiviral factors while protecting RSV-encoded viral proteins against autophagic degradation through an as-yet-unknown mechanism. This study showed that RSV CP plays dual roles in the autophagy-related interaction between plants and viruses.
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Affiliation(s)
- Wanying Zhao
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Li Wang
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Lipeng Li
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Tong Zhou
- Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Nanjing, 210095, China
| | - Fei Yan
- Institute of Plant Virology, Ningbo University, Ningbo, 312362, China
| | - Heng Zhang
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products, Institute of Virology and Biotechnology, Zhejiang Academy of Agricultural Sciences, Hangzhou, 310021, China
| | - Ying Zhu
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products, Institute of Virology and Biotechnology, Zhejiang Academy of Agricultural Sciences, Hangzhou, 310021, China
| | - Ida Bagus Andika
- College of Plant Health and Medicine, Qingdao Agricultural University, Qingdao, 266109, China
| | - Liying Sun
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, 712100, Shaanxi, China.
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Iriondo MN, Etxaniz A, Varela YR, Ballesteros U, Lázaro M, Valle M, Fracchiolla D, Martens S, Montes LR, Goñi FM, Alonso A. Effect of ATG12-ATG5-ATG16L1 autophagy E3-like complex on the ability of LC3/GABARAP proteins to induce vesicle tethering and fusion. Cell Mol Life Sci 2023; 80:56. [PMID: 36729310 PMCID: PMC9894987 DOI: 10.1007/s00018-023-04704-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Revised: 01/19/2023] [Accepted: 01/20/2023] [Indexed: 02/03/2023]
Abstract
In macroautophagy, the autophagosome (AP) engulfs portions of cytoplasm to allow their lysosomal degradation. AP formation in humans requires the concerted action of the ATG12 and LC3/GABARAP conjugation systems. The ATG12-ATG5-ATG16L1 or E3-like complex (E3 for short) acts as a ubiquitin-like E3 enzyme, promoting LC3/GABARAP proteins anchoring to the AP membrane. Their role in the AP expansion process is still unclear, in part because there are no studies comparing six LC3/GABARAP family member roles under the same conditions, and also because the full human E3 was only recently available. In the present study, the lipidation of six members of the LC3/GABARAP family has been reconstituted in the presence and absence of E3, and the mechanisms by which E3 and LC3/GABARAP proteins participate in vesicle tethering and fusion have been investigated. In the absence of E3, GABARAP and GABARAPL1 showed the highest activities. Differences found within LC3/GABARAP proteins suggest the existence of a lipidation threshold, lower for the GABARAP subfamily, as a requisite for tethering and inter-vesicular lipid mixing. E3 increases and speeds up lipidation and LC3/GABARAP-promoted tethering. However, E3 hampers LC3/GABARAP capacity to induce inter-vesicular lipid mixing or subsequent fusion, presumably through the formation of a rigid scaffold on the vesicle surface. Our results suggest a model of AP expansion in which the growing regions would be areas where the LC3/GABARAP proteins involved should be susceptible to lipidation in the absence of E3, or else a regulatory mechanism would allow vesicle incorporation and phagophore growth when E3 is present.
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Affiliation(s)
- Marina N Iriondo
- Instituto Biofisika (UPV/EHU, CSIC), University of the Basque Country, 48940, Leioa, Spain
- Department of Biochemistry and Molecular Biology, University of the Basque Country, 48940, Leioa, Spain
| | - Asier Etxaniz
- Instituto Biofisika (UPV/EHU, CSIC), University of the Basque Country, 48940, Leioa, Spain
- Department of Biochemistry and Molecular Biology, University of the Basque Country, 48940, Leioa, Spain
| | - Yaiza R Varela
- Instituto Biofisika (UPV/EHU, CSIC), University of the Basque Country, 48940, Leioa, Spain
- Department of Biochemistry and Molecular Biology, University of the Basque Country, 48940, Leioa, Spain
| | - Uxue Ballesteros
- Instituto Biofisika (UPV/EHU, CSIC), University of the Basque Country, 48940, Leioa, Spain
- Department of Biochemistry and Molecular Biology, University of the Basque Country, 48940, Leioa, Spain
| | - Melisa Lázaro
- CIC bioGUNE, Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, Building 800, 48160, Derio, Bizkaia, Spain
| | - Mikel Valle
- CIC bioGUNE, Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, Building 800, 48160, Derio, Bizkaia, Spain
| | - Dorotea Fracchiolla
- Max Perutz Labs, University of Vienna, Vienna BioCenter, Dr. Bohr-Gasse 9, 1030, Vienna, Austria
| | - Sascha Martens
- Max Perutz Labs, University of Vienna, Vienna BioCenter, Dr. Bohr-Gasse 9, 1030, Vienna, Austria
| | - L Ruth Montes
- Instituto Biofisika (UPV/EHU, CSIC), University of the Basque Country, 48940, Leioa, Spain
- Department of Biochemistry and Molecular Biology, University of the Basque Country, 48940, Leioa, Spain
| | - Félix M Goñi
- Instituto Biofisika (UPV/EHU, CSIC), University of the Basque Country, 48940, Leioa, Spain
- Department of Biochemistry and Molecular Biology, University of the Basque Country, 48940, Leioa, Spain
| | - Alicia Alonso
- Instituto Biofisika (UPV/EHU, CSIC), University of the Basque Country, 48940, Leioa, Spain.
- Department of Biochemistry and Molecular Biology, University of the Basque Country, 48940, Leioa, Spain.
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6
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Zhang Y, Ge J, Bian X, Kumar A. Quantitative Models of Lipid Transfer and Membrane Contact Formation. CONTACT (THOUSAND OAKS (VENTURA COUNTY, CALIF.)) 2022; 5:1-21. [PMID: 36120532 DOI: 10.1177/25152564221096024] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Lipid transfer proteins (LTPs) transfer lipids between different organelles, and thus play key roles in lipid homeostasis and organelle dynamics. The lipid transfer often occurs at the membrane contact sites (MCS) where two membranes are held within 10-30 nm. While most LTPs act as a shuttle to transfer lipids, recent experiments reveal a new category of eukaryotic LTPs that may serve as a bridge to transport lipids in bulk at MCSs. However, the molecular mechanisms underlying lipid transfer and MCS formation are not well understood. Here, we first review two recent studies of extended synaptotagmin (E-Syt)-mediated membrane binding and lipid transfer using novel approaches. Then we describe mathematical models to quantify the kinetics of lipid transfer by shuttle LTPs based on a lipid exchange mechanism. We find that simple lipid mixing among membranes of similar composition and/or lipid partitioning among membranes of distinct composition can explain lipid transfer against a concentration gradient widely observed for LTPs. We predict that selective transport of lipids, but not membrane proteins, by bridge LTPs leads to osmotic membrane tension by analogy to the osmotic pressure across a semipermeable membrane. A gradient of such tension and the conventional membrane tension may drive bulk lipid flow through bridge LTPs at a speed consistent with the fast membrane expansion observed in vivo. Finally, we discuss the implications of membrane tension and lipid transfer in organelle biogenesis. Overall, the quantitative models may help clarify the mechanisms of LTP-mediated MCS formation and lipid transfer.
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Affiliation(s)
- Yongli Zhang
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT, USA.,Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
| | - Jinghua Ge
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT, USA
| | - Xin Bian
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT, USA.,Department of Neuroscience, Yale University School of Medicine, New Haven, CT, USA.,Present address: State Key Laboratory of Medicinal Chemical Biology, College of Life Sciences, Nankai University, Tianjin, China
| | - Avinash Kumar
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT, USA
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7
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He CW, Cui XF, Ma SJ, Xu Q, Ran YP, Chen WZ, Mu JX, Li H, Zhu J, Gong Q, Xie Z. Membrane recruitment of Atg8 by Hfl1 facilitates turnover of vacuolar membrane proteins in yeast cells approaching stationary phase. BMC Biol 2021; 19:117. [PMID: 34088313 PMCID: PMC8176713 DOI: 10.1186/s12915-021-01048-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Accepted: 05/07/2021] [Indexed: 12/03/2022] Open
Abstract
Background The vacuole/lysosome is the final destination of autophagic pathways, but can also itself be degraded in whole or in part by selective macroautophagic or microautophagic processes. Diverse molecular mechanisms are involved in these processes, the characterization of which has lagged behind those of ATG-dependent macroautophagy and ESCRT-dependent endosomal multivesicular body pathways. Results Here we show that as yeast cells gradually exhaust available nutrients and approach stationary phase, multiple vacuolar integral membrane proteins with unrelated functions are degraded in the vacuolar lumen. This degradation depends on the ESCRT machinery, but does not strictly require ubiquitination of cargos or trafficking of cargos out of the vacuole. It is also temporally and mechanistically distinct from NPC-dependent microlipophagy. The turnover is facilitated by Atg8, an exception among autophagy proteins, and an Atg8-interacting vacuolar membrane protein, Hfl1. Lack of Atg8 or Hfl1 led to the accumulation of enlarged lumenal membrane structures in the vacuole. We further show that a key function of Hfl1 is the membrane recruitment of Atg8. In the presence of Hfl1, lipidation of Atg8 is not required for efficient cargo turnover. The need for Hfl1 can be partially bypassed by blocking Atg8 delipidation. Conclusions Our data reveal a vacuolar membrane protein degradation process with a unique dependence on vacuole-associated Atg8 downstream of ESCRTs, and we identify a specific role of Hfl1, a protein conserved from yeast to plants and animals, in membrane targeting of Atg8. Supplementary Information The online version contains supplementary material available at 10.1186/s12915-021-01048-7.
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Affiliation(s)
- Cheng-Wen He
- State Key Laboratory of Microbial Metabolism and Joint International Research Laboratory of Metabolic & Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Xue-Fei Cui
- State Key Laboratory of Microbial Metabolism and Joint International Research Laboratory of Metabolic & Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Shao-Jie Ma
- State Key Laboratory of Microbial Metabolism and Joint International Research Laboratory of Metabolic & Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, China.,Present address: Department of Genetics, Yale School of Medicine, New Haven, CT, 06510, USA
| | - Qin Xu
- State Key Laboratory of Microbial Metabolism and Joint International Research Laboratory of Metabolic & Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Yan-Peng Ran
- State Key Laboratory of Microbial Metabolism and Joint International Research Laboratory of Metabolic & Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Wei-Zhi Chen
- State Key Laboratory of Microbial Metabolism and Joint International Research Laboratory of Metabolic & Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Jun-Xi Mu
- State Key Laboratory of Microbial Metabolism and Joint International Research Laboratory of Metabolic & Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Hui Li
- State Key Laboratory of Microbial Metabolism and Joint International Research Laboratory of Metabolic & Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Jing Zhu
- State Key Laboratory of Microbial Metabolism and Joint International Research Laboratory of Metabolic & Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Qingqiu Gong
- State Key Laboratory of Microbial Metabolism and Joint International Research Laboratory of Metabolic & Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Zhiping Xie
- State Key Laboratory of Microbial Metabolism and Joint International Research Laboratory of Metabolic & Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, China.
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Swagatika S, Tomar RS. Cantharidin downregulates PSD1 expression and inhibits autophagic flux in yeast cells. FEBS Open Bio 2021; 12:1017-1035. [PMID: 33999504 PMCID: PMC9063437 DOI: 10.1002/2211-5463.13196] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 04/07/2021] [Accepted: 05/14/2021] [Indexed: 11/10/2022] Open
Abstract
Cantharidin is a terpenoid compound of insect origin, naturally produced by male blister beetles as an anti-predatory mechanism. Cantharidin has anticancer properties, which are attributed to its ability to induce cell cycle arrest, DNA damage, MAPK signalling pathway and apoptosis. Cantharidin has been reported to induce apoptosis in triple-negative breast cancer cells by suppressing autophagy via downregulation of Beclin 1 expression and autophagosome formation. However, it remains unclear which stage of the autophagic pathway is targeted by cantharidin. Herein, we report that yeast cells are sensitive to cantharidin, and external supplementation of ethanolamine (ETA) ameliorates the cytotoxicity. In addition, cantharidin downregulates phosphatidylserine decarboxylase1 (PSD1) expression. We also report that cantharidin inhibits autophagic flux, and external administration of ETA could rescue this inhibition. Additionally, co-treatment with chloroquine sensitized the autophagy inhibitory effects of cantharidin. We conclude that yeast cells are sensitive to cantharidin due to inhibition of autophagic flux.
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Affiliation(s)
- Swati Swagatika
- Laboratory of Chromatin Biology, Department of Biological Sciences, Indian Institute of Science Education and Research (IISER), Bhopal-462066, MP, India
| | - Raghuvir Singh Tomar
- Laboratory of Chromatin Biology, Department of Biological Sciences, Indian Institute of Science Education and Research (IISER), Bhopal-462066, MP, India
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Jacquet M, Guittaut M, Fraichard A, Despouy G. The functions of Atg8-family proteins in autophagy and cancer: linked or unrelated? Autophagy 2021; 17:599-611. [PMID: 32255730 PMCID: PMC8032235 DOI: 10.1080/15548627.2020.1749367] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2019] [Revised: 03/09/2020] [Accepted: 03/26/2020] [Indexed: 01/04/2023] Open
Abstract
The Atg8-family proteins are subdivided into two subfamilies: the GABARAP and LC3 subfamilies. These proteins, which are major players of the autophagy pathway, present a conserved glycine in their C-terminus necessary for their association to the autophagosome membrane. This family of proteins present multiple roles from autophagy induction to autophagosome-lysosome fusion and have been described to play a role during cancer progression. Indeed, GABARAPs are described to be downregulated in cancers, and high expression has been linked to a good prognosis. Regarding LC3 s, their expression does not correlate to a particular tumor type or stage. The involvement of Atg8-family proteins during cancer, therefore, remains unclear, and it appears that their anti-tumor role may be associated with their implication in selective protein degradation by autophagy but might also be independent, in some cases, of their conjugation to autophagosomes. In this review, we will then focus on the involvement of GABARAP and LC3 subfamilies during autophagy and cancer and highlight the similarities but also the differences of action of each subfamily member.Abbreviations: AIM: Atg8-interacting motif; AMPK: adenosine monophosphate-associated protein kinase; ATG: autophagy-related; BECN1: beclin 1; BIRC6/BRUCE: baculoviral IAP repeat containing 6; BNIP3L/NIX: BCL2 interacting protein 3 like; GABARAP: GABA type A receptor-associated protein; GABARAPL1/2: GABA type A receptor associated protein like 1/2; GABRA/GABAA: gamma-aminobutyric acid type A receptor subunit; LAP: LC3-associated phagocytosis; LMNB1: lamin B1; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; MTOR: mechanistic target of rapamycin kinase; PI4K2A/PI4KIIα: phosphatidylinositol 4-kinase type 2 alpha; PLEKHM1: plecktrin homology and RUN domain containing M1; PtdIns3K-C1: class III phosphatidylinositol 3-kinase complex 1; SQSTM1: sequestosome 1; ULK1: unc51-like autophagy activating kinase 1.
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Affiliation(s)
- Marine Jacquet
- Univ. Bourgogne Franche-Comté, INSERM, EFS BFC, UMR1098, Interactions Hôte-Greffon-Tumeur/Ingénierie Cellulaire et Génique, Besançon, France
| | - Michaël Guittaut
- Univ. Bourgogne Franche-Comté, INSERM, EFS BFC, UMR1098, Interactions Hôte-Greffon-Tumeur/Ingénierie Cellulaire et Génique, Besançon, France
- DImaCell Platform, Univ. Bourgogne Franche-Comté, Besançon, France
| | - Annick Fraichard
- Univ. Bourgogne Franche-Comté, INSERM, EFS BFC, UMR1098, Interactions Hôte-Greffon-Tumeur/Ingénierie Cellulaire et Génique, Besançon, France
| | - Gilles Despouy
- Univ. Bourgogne Franche-Comté, INSERM, EFS BFC, UMR1098, Interactions Hôte-Greffon-Tumeur/Ingénierie Cellulaire et Génique, Besançon, France
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10
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Abstract
Post-translational modifications of cellular substrates with ubiquitin and ubiquitin-like proteins (UBLs), including ubiquitin, SUMOs, and neural precursor cell-expressed developmentally downregulated protein 8, play a central role in regulating many aspects of cell biology. The UBL conjugation cascade is initiated by a family of ATP-dependent enzymes termed E1 activating enzymes and executed by the downstream E2-conjugating enzymes and E3 ligases. Despite their druggability and their key position at the apex of the cascade, pharmacologic modulation of E1s with potent and selective drugs has remained elusive until 2009. Among the eight E1 enzymes identified so far, those initiating ubiquitylation (UBA1), SUMOylation (SAE), and neddylation (NAE) are the most characterized and are implicated in various aspects of cancer biology. To date, over 40 inhibitors have been reported to target UBA1, SAE, and NAE, including the NAE inhibitor pevonedistat, evaluated in more than 30 clinical trials. In this Review, we discuss E1 enzymes, the rationale for their therapeutic targeting in cancer, and their different inhibitors, with emphasis on the pharmacologic properties of adenosine sulfamates and their unique mechanism of action, termed substrate-assisted inhibition. Moreover, we highlight other less-characterized E1s-UBA6, UBA7, UBA4, UBA5, and autophagy-related protein 7-and the opportunities for targeting these enzymes in cancer. SIGNIFICANCE STATEMENT: The clinical successes of proteasome inhibitors in cancer therapy and the emerging resistance to these agents have prompted the exploration of other signaling nodes in the ubiquitin-proteasome system including E1 enzymes. Therefore, it is crucial to understand the biology of different E1 enzymes, their roles in cancer, and how to translate this knowledge into novel therapeutic strategies with potential implications in cancer treatment.
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Affiliation(s)
- Samir H Barghout
- Department of Medical Biophysics, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada (S.H.B., A.D.S.); Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario, Canada (S.H.B., A.D.S.); and Department of Pharmacology and Toxicology, Faculty of Pharmacy, Tanta University, Tanta, Egypt (S.H.B.)
| | - Aaron D Schimmer
- Department of Medical Biophysics, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada (S.H.B., A.D.S.); Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario, Canada (S.H.B., A.D.S.); and Department of Pharmacology and Toxicology, Faculty of Pharmacy, Tanta University, Tanta, Egypt (S.H.B.)
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11
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Jiao Y, An M, Li X, Yu M, Zhao X, Xia Z, Wu Y. Transcriptomic and functional analyses reveal an antiviral role of autophagy during pepper mild mottle virus infection. BMC PLANT BIOLOGY 2020; 20:495. [PMID: 33121441 PMCID: PMC7596970 DOI: 10.1186/s12870-020-02711-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Accepted: 10/20/2020] [Indexed: 05/03/2023]
Abstract
BACKGROUND Pepper mild mottle virus (PMMoV) is a member in the genus Tobamovirus and infects mainly solanaceous plants. However, the mechanism of virus-host interactions remains unclear. To explore the responses of pepper plants to PMMoV infection, we analyzed the transcriptomic changes in pepper plants after PMMoV infection using a high-throughput RNA sequencing approach and explored the roles of host autophagy in regulating PMMoV infection. RESULTS A total of 197 differentially expressed genes (DEGs) were obtained after PMMoV infection, including 172 significantly up-regulated genes and 25 down-regulated genes. The Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses revealed that most up-regulated DEGs were involved in plant abiotic and biotic stresses. Further analyses showed the expressions of multiple autophagy-related genes (ATGs) were increased after PMMoV infection in pepper and Nicotiana benthamiana plants. Through confocal microscopy and transmission electron microscopy, we have found that PMMoV infection in plant can induce autophagy, evidenced by the increased number of GFP-ATG8a fluorescent punctate and the appearance of double membrane autophagic structures in cells of N. benthamiana. Additionally, inhibition of autophagy significantly increased PMMoV RNA accumulation and aggravated systemic PMMoV symptoms through autophagy inhibitor (3-MA and E64d) treatment and silencing of NbATG expressions by a Tobacco rattle virus-induced gene silencing assays. These results indicated that autophagy played a positive role in plant resistance to PMMoV infection. CONCLUSIONS Taken together, our results provide a transcriptomic insight into pepper responding to PMMoV infection and reveal that autophagy induced by PMMoV infection has an antiviral role in regulating PMMoV infection. These results also help us to better understand the mechanism controlling PMMoV infection in plants and to develop better strategies for breeding projects for virus-resistant crops.
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Affiliation(s)
- Yubing Jiao
- College of Plant Protection, Shenyang Agricultural University, Shenyang, 110866, China
| | - Mengnan An
- College of Plant Protection, Shenyang Agricultural University, Shenyang, 110866, China
| | - Xiaodong Li
- General Station of Forest and Grassland Pest and Diseases Control, National Forestry and Grassland Administration, Shenyang, 110034, China
| | - Man Yu
- College of Plant Protection, Shenyang Agricultural University, Shenyang, 110866, China
| | - Xiuxiang Zhao
- College of Plant Protection, Shenyang Agricultural University, Shenyang, 110866, China
| | - Zihao Xia
- College of Plant Protection, Shenyang Agricultural University, Shenyang, 110866, China.
| | - Yuanhua Wu
- College of Plant Protection, Shenyang Agricultural University, Shenyang, 110866, China.
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12
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Dhakal S, Macreadie I. Protein Homeostasis Networks and the Use of Yeast to Guide Interventions in Alzheimer's Disease. Int J Mol Sci 2020; 21:E8014. [PMID: 33126501 PMCID: PMC7662794 DOI: 10.3390/ijms21218014] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 10/24/2020] [Accepted: 10/26/2020] [Indexed: 12/12/2022] Open
Abstract
Alzheimer's Disease (AD) is a progressive multifactorial age-related neurodegenerative disorder that causes the majority of deaths due to dementia in the elderly. Although various risk factors have been found to be associated with AD progression, the cause of the disease is still unresolved. The loss of proteostasis is one of the major causes of AD: it is evident by aggregation of misfolded proteins, lipid homeostasis disruption, accumulation of autophagic vesicles, and oxidative damage during the disease progression. Different models have been developed to study AD, one of which is a yeast model. Yeasts are simple unicellular eukaryotic cells that have provided great insights into human cell biology. Various yeast models, including unmodified and genetically modified yeasts, have been established for studying AD and have provided significant amount of information on AD pathology and potential interventions. The conservation of various human biological processes, including signal transduction, energy metabolism, protein homeostasis, stress responses, oxidative phosphorylation, vesicle trafficking, apoptosis, endocytosis, and ageing, renders yeast a fascinating, powerful model for AD. In addition, the easy manipulation of the yeast genome and availability of methods to evaluate yeast cells rapidly in high throughput technological platforms strengthen the rationale of using yeast as a model. This review focuses on the description of the proteostasis network in yeast and its comparison with the human proteostasis network. It further elaborates on the AD-associated proteostasis failure and applications of the yeast proteostasis network to understand AD pathology and its potential to guide interventions against AD.
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Affiliation(s)
| | - Ian Macreadie
- School of Science, RMIT University, Bundoora, Victoria 3083, Australia;
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13
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Sora V, Kumar M, Maiani E, Lambrughi M, Tiberti M, Papaleo E. Structure and Dynamics in the ATG8 Family From Experimental to Computational Techniques. Front Cell Dev Biol 2020; 8:420. [PMID: 32587856 PMCID: PMC7297954 DOI: 10.3389/fcell.2020.00420] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Accepted: 05/06/2020] [Indexed: 12/31/2022] Open
Abstract
Autophagy is a conserved and essential intracellular mechanism for the removal of damaged components. Since autophagy deregulation is linked to different kinds of pathologies, it is fundamental to gain knowledge on the fine molecular and structural details related to the core proteins of the autophagy machinery. Among these, the family of human ATG8 proteins plays a central role in recruiting other proteins to the different membrane structures involved in the autophagic pathway. Several experimental structures are available for the members of the ATG8 family alone or in complex with their different biological partners, including disordered regions of proteins containing a short linear motif called LC3 interacting motif. Recently, the first structural details of the interaction of ATG8 proteins with biological membranes came into light. The availability of structural data for human ATG8 proteins has been paving the way for studies on their structure-function-dynamic relationship using biomolecular simulations. Experimental and computational structural biology can help to address several outstanding questions on the mechanism of human ATG8 proteins, including their specificity toward different interactors, their association with membranes, the heterogeneity of their conformational ensemble, and their regulation by post-translational modifications. We here summarize the main results collected so far and discuss the future perspectives within the field and the knowledge gaps. Our review can serve as a roadmap for future structural and dynamics studies of the ATG8 family members in health and disease.
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Affiliation(s)
- Valentina Sora
- Computational Biology Laboratory, Center for Autophagy, Recycling and Disease, Danish Cancer Society Research Center, Copenhagen, Denmark
| | - Mukesh Kumar
- Computational Biology Laboratory, Center for Autophagy, Recycling and Disease, Danish Cancer Society Research Center, Copenhagen, Denmark
| | - Emiliano Maiani
- Computational Biology Laboratory, Center for Autophagy, Recycling and Disease, Danish Cancer Society Research Center, Copenhagen, Denmark
| | - Matteo Lambrughi
- Computational Biology Laboratory, Center for Autophagy, Recycling and Disease, Danish Cancer Society Research Center, Copenhagen, Denmark
| | - Matteo Tiberti
- Computational Biology Laboratory, Center for Autophagy, Recycling and Disease, Danish Cancer Society Research Center, Copenhagen, Denmark
| | - Elena Papaleo
- Computational Biology Laboratory, Center for Autophagy, Recycling and Disease, Danish Cancer Society Research Center, Copenhagen, Denmark
- Translational Disease System Biology, Faculty of Health and Medical Sciences, Novo Nordisk Foundation Center for Protein Research, University of Copenhagen, Copenhagen, Denmark
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14
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Dobner J, Simons IM, Rufinatscha K, Hänsch S, Schwarten M, Weiergräber OH, Abdollahzadeh I, Gensch T, Bode JG, Hoffmann S, Willbold D. Deficiency of GABARAP but not its Paralogs Causes Enhanced EGF-induced EGFR Degradation. Cells 2020; 9:E1296. [PMID: 32456010 PMCID: PMC7291022 DOI: 10.3390/cells9051296] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Revised: 05/19/2020] [Accepted: 05/20/2020] [Indexed: 12/20/2022] Open
Abstract
The γ-aminobutyric acid type A receptor-associated protein (GABARAP) and its close paralogs GABARAPL1 and GABARAPL2 constitute a subfamily of the autophagy-related 8 (Atg8) protein family. Being associated with a variety of dynamic membranous structures of autophagic and non-autophagic origin, Atg8 proteins functionalize membranes by either serving as docking sites for other proteins or by acting as membrane tethers or adhesion factors. In this study, we describe that deficiency for GABARAP alone, but not for its close paralogs, is sufficient for accelerated EGF receptor (EGFR) degradation in response to EGF, which is accompanied by the downregulation of EGFR-mediated MAPK signaling, altered target gene expression, EGF uptake, and EGF vesicle composition over time. We further show that GABARAP and EGFR converge in the same distinct compartments at endogenous GABARAP expression levels in response to EGF stimulation. Furthermore, GABARAP associates with EGFR in living cells and binds to synthetic peptides that are derived from the EGFR cytoplasmic tail in vitro. Thus, our data strongly indicate a unique and novel role for GABARAP during EGFR trafficking.
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Affiliation(s)
- Jochen Dobner
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany; (J.D.); (I.M.S.)
| | - Indra M. Simons
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany; (J.D.); (I.M.S.)
- Institute of Biological Information Processing: Structural Biochemistry (IBI-7), Forschungszentrum Jülich, 52425 Jülich, Germany; (M.S.); (O.H.W.); (I.A.); (S.H.)
| | - Kerstin Rufinatscha
- Department of Gastroenterology, Hepatology and Infectiology, University Hospital, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany; (K.R.); (J.G.B.)
| | - Sebastian Hänsch
- Department of Biology, Center for Advanced Imaging (CAi), Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany;
| | - Melanie Schwarten
- Institute of Biological Information Processing: Structural Biochemistry (IBI-7), Forschungszentrum Jülich, 52425 Jülich, Germany; (M.S.); (O.H.W.); (I.A.); (S.H.)
| | - Oliver H. Weiergräber
- Institute of Biological Information Processing: Structural Biochemistry (IBI-7), Forschungszentrum Jülich, 52425 Jülich, Germany; (M.S.); (O.H.W.); (I.A.); (S.H.)
| | - Iman Abdollahzadeh
- Institute of Biological Information Processing: Structural Biochemistry (IBI-7), Forschungszentrum Jülich, 52425 Jülich, Germany; (M.S.); (O.H.W.); (I.A.); (S.H.)
- Institute of Biological Information Processing: Molecular and Cell Physiology (IBI-1), Forschungszentrum Jülich, 52425 Jülich, Germany;
| | - Thomas Gensch
- Institute of Biological Information Processing: Molecular and Cell Physiology (IBI-1), Forschungszentrum Jülich, 52425 Jülich, Germany;
| | - Johannes G. Bode
- Department of Gastroenterology, Hepatology and Infectiology, University Hospital, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany; (K.R.); (J.G.B.)
| | - Silke Hoffmann
- Institute of Biological Information Processing: Structural Biochemistry (IBI-7), Forschungszentrum Jülich, 52425 Jülich, Germany; (M.S.); (O.H.W.); (I.A.); (S.H.)
| | - Dieter Willbold
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany; (J.D.); (I.M.S.)
- Institute of Biological Information Processing: Structural Biochemistry (IBI-7), Forschungszentrum Jülich, 52425 Jülich, Germany; (M.S.); (O.H.W.); (I.A.); (S.H.)
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15
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Brooks D, Naeem F, Stetsiv M, Goetting SC, Bawa S, Green N, Clark C, Bashirullah A, Geisbrecht ER. Drosophila NUAK functions with Starvin/BAG3 in autophagic protein turnover. PLoS Genet 2020; 16:e1008700. [PMID: 32320396 PMCID: PMC7176095 DOI: 10.1371/journal.pgen.1008700] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Accepted: 02/28/2020] [Indexed: 11/18/2022] Open
Abstract
The inability to remove protein aggregates in post-mitotic cells such as muscles or neurons is a cellular hallmark of aging cells and is a key factor in the initiation and progression of protein misfolding diseases. While protein aggregate disorders share common features, the molecular level events that culminate in abnormal protein accumulation cannot be explained by a single mechanism. Here we show that loss of the serine/threonine kinase NUAK causes cellular degeneration resulting from the incomplete clearance of protein aggregates in Drosophila larval muscles. In NUAK mutant muscles, regions that lack the myofibrillar proteins F-actin and Myosin heavy chain (MHC) instead contain damaged organelles and the accumulation of select proteins, including Filamin (Fil) and CryAB. NUAK biochemically and genetically interacts with Drosophila Starvin (Stv), the ortholog of mammalian Bcl-2-associated athanogene 3 (BAG3). Consistent with a known role for the co-chaperone BAG3 and the Heat shock cognate 71 kDa (HSC70)/HSPA8 ATPase in the autophagic clearance of proteins, RNA interference (RNAi) of Drosophila Stv, Hsc70-4, or autophagy-related 8a (Atg8a) all exhibit muscle degeneration and muscle contraction defects that phenocopy NUAK mutants. We further demonstrate that Fil is a target of NUAK kinase activity and abnormally accumulates upon loss of the BAG3-Hsc70-4 complex. In addition, Ubiquitin (Ub), ref(2)p/p62, and Atg8a are increased in regions of protein aggregation, consistent with a block in autophagy upon loss of NUAK. Collectively, our results establish a novel role for NUAK with the Stv-Hsc70-4 complex in the autophagic clearance of proteins that may eventually lead to treatment options for protein aggregate diseases.
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Affiliation(s)
- David Brooks
- Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, KS, United States of America
| | - Fawwaz Naeem
- Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, KS, United States of America
| | - Marta Stetsiv
- Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, KS, United States of America
| | - Samantha C Goetting
- Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, KS, United States of America
| | - Simranjot Bawa
- Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, KS, United States of America
| | - Nicole Green
- Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, KS, United States of America
| | - Cheryl Clark
- Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, KS, United States of America
| | - Arash Bashirullah
- Division of Pharmaceutical Sciences, University of Wisconsin-Madison, Madison, WI, United States of America
| | - Erika R Geisbrecht
- Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, KS, United States of America
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16
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Eickhorst C, Licheva M, Kraft C. Scaffold proteins in bulk and selective autophagy. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2020; 172:15-35. [PMID: 32620241 DOI: 10.1016/bs.pmbts.2020.01.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Autophagy is a crucial cellular degradation and recycling pathway. During autophagy double-membrane vesicles, called autophagosomes, encapsulate cellular components and deliver their cargo to the lytic compartment for degradation. Formation of autophagosomes is regulated by the Atg1 kinase complex in yeast and the homologous ULK1 kinase complex in mammals. While research on Atg1 and ULK1 has advanced our understanding of how these protein kinases function in autophagy, the other Atg1/ULK1 kinase complex members have received much less attention. Here, we focus on the functions of the Atg1 kinase complex members Atg11 and Atg17 as well as the ULK1 kinase complex member FIP200 in autophagy. These three proteins act as scaffolds in their respective complexes. Recent studies have made it evident that they have similar but also distinct functions. In this article, we review our current understanding of how these scaffold proteins function from autophagosome formation to fusion and also discuss their possible roles in diseases.
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Affiliation(s)
- Christopher Eickhorst
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany; Faculty of Biology, University of Freiburg, Freiburg, Germany; Spemann Graduate School of Biology and Medicine (SGBM), University of Freiburg, Freiburg, Germany
| | - Mariya Licheva
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany; Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Claudine Kraft
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany; CIBSS-Centre for Integrative Biological Signalling Studies, University of Freiburg, Freiburg, Germany.
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17
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Huber J, Obata M, Gruber J, Akutsu M, Löhr F, Rogova N, Güntert P, Dikic I, Kirkin V, Komatsu M, Dötsch V, Rogov VV. An atypical LIR motif within UBA5 (ubiquitin like modifier activating enzyme 5) interacts with GABARAP proteins and mediates membrane localization of UBA5. Autophagy 2020; 16:256-270. [PMID: 30990354 PMCID: PMC6984602 DOI: 10.1080/15548627.2019.1606637] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Revised: 03/15/2019] [Accepted: 03/27/2019] [Indexed: 12/15/2022] Open
Abstract
Short linear motifs, known as LC3-interacting regions (LIRs), interact with mactoautophagy/autophagy modifiers (Atg8/LC3/GABARAP proteins) via a conserved universal mechanism. Typically, this includes the occupancy of 2 hydrophobic pockets on the surface of Atg8-family proteins by 2 specific aromatic and hydrophobic residues within the LIR motifs. Here, we describe an alternative mechanism of Atg8-family protein interaction with the non-canonical UBA5 LIR, an E1-like enzyme of the ufmylation pathway that preferentially interacts with GABARAP but not LC3 proteins. By solving the structures of both GABARAP and GABARAPL2 in complex with the UBA5 LIR, we show that in addition to the binding to the 2 canonical hydrophobic pockets (HP1 and HP2), a conserved tryptophan residue N-terminal of the LIR core sequence binds into a novel hydrophobic pocket on the surface of GABARAP proteins, which we term HP0. This mode of action is unique for UBA5 and accompanied by large rearrangements of key residues including the side chains of the gate-keeping K46 and the adjacent K/R47 in GABARAP proteins. Swapping mutations in LC3B and GABARAPL2 revealed that K/R47 is the key residue in the specific binding of GABARAP proteins to UBA5, with synergetic contributions of the composition and dynamics of the loop L3. Finally, we elucidate the physiological relevance of the interaction and show that GABARAP proteins regulate the localization and function of UBA5 on the endoplasmic reticulum membrane in a lipidation-independent manner.Abbreviations: ATG: AuTophaGy-related; EGFP: enhanced green fluorescent protein; GABARAP: GABA-type A receptor-associated protein; ITC: isothermal titration calorimetry; KO: knockout; LIR: LC3-interacting region; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; NMR: nuclear magnetic resonance; RMSD: root-mean-square deviation of atomic positions; TKO: triple knockout; UBA5: ubiquitin like modifier activating enzyme 5.
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Affiliation(s)
- Jessica Huber
- Institute of Biophysical Chemistry and Center for Biomolecular Magnetic Resonance, Goethe University, Frankfurt am Main, Germany
| | - Miki Obata
- Department of Biochemistry, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
| | - Jens Gruber
- Institute of Biophysical Chemistry and Center for Biomolecular Magnetic Resonance, Goethe University, Frankfurt am Main, Germany
| | - Masato Akutsu
- Buchmann Institute for Molecular Life Sciences, Goethe University, Frankfurt am Main, Germany
| | - Frank Löhr
- Institute of Biophysical Chemistry and Center for Biomolecular Magnetic Resonance, Goethe University, Frankfurt am Main, Germany
| | - Natalia Rogova
- Institute of Biophysical Chemistry and Center for Biomolecular Magnetic Resonance, Goethe University, Frankfurt am Main, Germany
| | - Peter Güntert
- Institute of Biophysical Chemistry and Center for Biomolecular Magnetic Resonance, Goethe University, Frankfurt am Main, Germany
- Laboratory of Physical Chemistry, ETH Zurich, Zurich, Switzerland
- Graduate School of Science, Tokyo Metropolitan University, Tokyo, Japan
| | - Ivan Dikic
- Buchmann Institute for Molecular Life Sciences, Goethe University, Frankfurt am Main, Germany
- Institute of Biochemistry II, School of Medicine, Frankfurt am Main, Germany
| | - Vladimir Kirkin
- Cancer Research UK Cancer Therapeutics Unit, The Institute of Cancer Research, London, UK
| | - Masaaki Komatsu
- Department of Biochemistry, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
- Department of Physiology, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Volker Dötsch
- Institute of Biophysical Chemistry and Center for Biomolecular Magnetic Resonance, Goethe University, Frankfurt am Main, Germany
| | - Vladimir V. Rogov
- Institute of Biophysical Chemistry and Center for Biomolecular Magnetic Resonance, Goethe University, Frankfurt am Main, Germany
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18
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Giri S, Shaha C. Leishmania donovani parasite requires Atg8 protein for infectivity and survival under stress. Cell Death Dis 2019; 10:808. [PMID: 31649242 PMCID: PMC6813314 DOI: 10.1038/s41419-019-2038-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Revised: 09/26/2019] [Accepted: 10/03/2019] [Indexed: 12/18/2022]
Abstract
The importance of autophagy in parasites with a digenetic life cycle like Leishmania spp. is significant. The parasite survives as promastigotes in the insect gut and as immotile amastigotes in mammals. This study demonstrates increased autophagy in Leishmania parasite during progression of in vitro life cycle and upon exposure to stress stimuli like starvation, oxidative stress, and drugs. Autophagy inhibition during stress exposure increased cell death, indicating the importance of autophagy in cellular defense against adverse conditions. Atg8 protein, a homolog of mammalian autophagy protein LC3 is expressed in Leishmania parasite but its function remains unknown. Overexpression of Atg8 (Atg8-OE) rendered the parasites resistant to stress and capable of infecting macrophages in substantial numbers; however, disruption of the Atg8 gene (ΔAtg8) resulting in suppression of Atg8 protein expression, increased susceptibility to stress and reduced the capability to cause infection. A critical event in the Leishmania parasite lifecycle is the differentiation of promastigote forms to the disease causing amastigote forms. The failure of ΔAtg8 parasites lacking Atg8 protein to differentiate into amastigotes, unlike the Atg8-OE and vector-transfected parasites, clearly indicated Atg8 involvement in a crucial event. The inability of ΔAtg8 parasites to infect macrophages in vitro was verified in an in vivo mouse model of leishmaniases where infection could not be induced by the ΔAtg8 parasites. Autophagy is known to be involved in the remodeling of damaged organelles. The accumulation of Atg8 around damaged mitochondria suggested increase of autophagy in the vicinity of the organelle. This buildup was prevented when mitochondria generated reactive oxygen species that were quenched, suggesting them as possible signaling molecules for sensing mitochondrial instability. In summary, our study provides new evidences for a crucial role of Atg8 protein in sustaining Leishmania parasite survival during life cycle and stress exposure, differentiation to amastigotes, and their infective abilities.
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Affiliation(s)
- Sagnik Giri
- Cell Death and Differentiation Laboratory, National Institute of Immunology, New Delhi, 110067, India
| | - Chandrima Shaha
- Cell Death and Differentiation Laboratory, National Institute of Immunology, New Delhi, 110067, India.
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19
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Ishii A, Kurokawa K, Hotta M, Yoshizaki S, Kurita M, Koyama A, Nakano A, Kimura Y. Role of Atg8 in the regulation of vacuolar membrane invagination. Sci Rep 2019; 9:14828. [PMID: 31616012 PMCID: PMC6794316 DOI: 10.1038/s41598-019-51254-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Accepted: 09/26/2019] [Indexed: 01/23/2023] Open
Abstract
Cellular heat stress can cause damage, and significant changes, to a variety of cellular structures. When exposed to chronically high temperatures, yeast cells invaginate vacuolar membranes. In this study, we found that the expression of Atg8, an essential autophagy factor, is induced after chronic heat stress. In addition, without Atg8, vacuolar invaginations are induced conspicuously, beginning earlier and invaginating vacuoles more frequently after heat stress. Our results indicate that Atg8's invagination-suppressing functions do not require Atg8 lipidation, in contrast with autophagy, which requires Atg8 lipidation. Genetic analyses of vps24 and vps23 further suggest that full ESCRT machinery is necessary to form vacuolar invaginations irrespective of Atg8. In contrast, through a combined mutation with the vacuole BAR domain protein Ivy1, vacuoles show constitutively enhanced invaginated structures. Finally, we found that the atg8Δivy1Δ mutant is sensitive against agents targeting functions of the vacuole and/or plasma membrane (cell wall). Collectively, our findings revealed that Atg8 maintains vacuolar membrane homeostasis in an autophagy-independent function by coordinating with other cellular factors.
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Affiliation(s)
- Ayane Ishii
- Graduate School of Integrated Science and Technology, Shizuoka University, Shizuoka, 422-8529, Japan
| | - Kazuo Kurokawa
- Live Cell Super-Resolution Imaging Research Team, RIKEN Center for Advanced Photonics, Wako, Saitama, 351-0198, Japan
| | - Miyuu Hotta
- Department of Agriculture, Shizuoka University, Shizuoka, 422-8529, Japan
| | - Suzuka Yoshizaki
- Department of Agriculture, Shizuoka University, Shizuoka, 422-8529, Japan
| | - Maki Kurita
- Graduate School of Integrated Science and Technology, Shizuoka University, Shizuoka, 422-8529, Japan
| | - Aya Koyama
- Department of Agriculture, Shizuoka University, Shizuoka, 422-8529, Japan
| | - Akihiko Nakano
- Live Cell Super-Resolution Imaging Research Team, RIKEN Center for Advanced Photonics, Wako, Saitama, 351-0198, Japan
| | - Yoko Kimura
- Graduate School of Integrated Science and Technology, Shizuoka University, Shizuoka, 422-8529, Japan. .,Department of Agriculture, Shizuoka University, Shizuoka, 422-8529, Japan.
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20
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Huang L, Yue J. The interplay of autophagy and enterovirus. Semin Cell Dev Biol 2019; 101:12-19. [PMID: 31563390 PMCID: PMC7102577 DOI: 10.1016/j.semcdb.2019.08.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2019] [Revised: 08/02/2019] [Accepted: 08/02/2019] [Indexed: 12/19/2022]
Abstract
Autophagy, an evolutional conserved lysosomal degradation process, has been implicated to play an important role in cellular defense against a variety of microbial infection. Interestingly, numerous studies found that some pathogens, especially positive-single-strand RNA viruses, actually hijacked autophagy machinery to promote virus infection within host cells, facilitating different stages of viral life cycle, from replication, assembly to egress. Enterovirus, a genus of positive-strand RNA virus, can cause various human diseases and is one of main public health threat globally, yet no effective clinical intervention is available for enterovirus infection. Here we summarized recent literature on how enteroviruses regulate and utilize autophagy process to facilitate their propagation in the host cells. The studies on the interplay between enterovirus and autophagy not only shed light on the molecular mechanisms underlying how enterovirus hijacks cellular components and pathway for its own benefits, but also provide therapeutic option against enterovirus infection.
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Affiliation(s)
- Lihong Huang
- City University of Hong Kong ShenZhen Research Institute, ShenZhen, China
| | - Jianbo Yue
- Department of Biomedical Sciences, City University of Hong Kong, Hong Kong, China.
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21
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Kushwaha NK, Hafrén A, Hofius D. Autophagy-virus interplay in plants: from antiviral recognition to proviral manipulation. MOLECULAR PLANT PATHOLOGY 2019; 20:1211-1216. [PMID: 31397085 PMCID: PMC6715616 DOI: 10.1111/mpp.12852] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Autophagy is a conserved self-cleaning and renewal system required for cellular homeostasis and stress tolerance. Autophagic processes are also implicated in the response to 'non-self' such as viral pathogens, yet the functions and mechanisms of autophagy during plant virus infection have only recently started to be revealed. Compelling evidence now indicates that autophagy is an integral part of antiviral immunity in plants. It can promote the hypersensitive cell death response upon incompatible viral infections or mediate the selective elimination of entire particles and individual proteins from compatible viruses in a pathway similar to xenophagy in animals. Several viruses, however, have evolved measures to antagonize xenophagic degradation or utilize autophagy to suppress disease-associated cell death and other defence pathways like RNA silencing. Here, we highlight the current advances and gaps in our understanding of the complex autophagy-virus interplay and its consequences for host immunity and viral pathogenesis in plants.
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Affiliation(s)
- Nirbhay Kumar Kushwaha
- Department of Plant Biology, Uppsala BioCenterSwedish University of Agricultural Sciences and Linnean Center of Plant BiologySE‐75007UppsalaSweden
| | - Anders Hafrén
- Department of Plant Biology, Uppsala BioCenterSwedish University of Agricultural Sciences and Linnean Center of Plant BiologySE‐75007UppsalaSweden
| | - Daniel Hofius
- Department of Plant Biology, Uppsala BioCenterSwedish University of Agricultural Sciences and Linnean Center of Plant BiologySE‐75007UppsalaSweden
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22
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Mishra R, Upadhyay A, Prajapati VK, Dhiman R, Poluri KM, Jana NR, Mishra A. LRSAM1 E3 ubiquitin ligase: molecular neurobiological perspectives linked with brain diseases. Cell Mol Life Sci 2019; 76:2093-2110. [PMID: 30826859 PMCID: PMC11105512 DOI: 10.1007/s00018-019-03055-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2018] [Revised: 02/13/2019] [Accepted: 02/21/2019] [Indexed: 01/01/2023]
Abstract
Cellular protein quality control (PQC) plays a significant role in the maintenance of cellular homeostasis. Failure of PQC mechanism may lead to various neurodegenerative diseases due to accumulation of aberrant proteins. To avoid such fatal neuronal conditions PQC employs autophagy and ubiquitin proteasome system (UPS) to degrade misfolded proteins. Few quality control (QC) E3 ubiquitin ligases interplay an important role to specifically recognize misfolded proteins for their intracellular degradation. Leucine-rich repeat and sterile alpha motif-containing 1 (LRSAM1) is a really interesting new gene (RING) class protein that possesses E3 ubiquitin ligase activity with promising applications in PQC. LRSAM1 is also known as RING finger leucine repeat rich (RIFLE) or TSG 101-associated ligase (TAL). LRSAM1 has various cellular functions as it modulates the protein aggregation, endosomal sorting machinery and virus egress from the cells. Thus, this makes LRSAM1 interesting to study not only in protein conformational disorders such as neurodegeneration but also in immunological and other cancerous disorders. Furthermore, LRSAM1 interacts with both cellular protein degradation machineries and hence it can participate in maintenance of overall cellular proteostasis. Still, more research work on the quality control molecular functions of LRSAM1 is needed to comprehend its roles in various protein aggregatory diseases. Earlier findings suggest that in a mouse model of Charcot-Marie-Tooth (CMT) disease, lack of LRSAM1 functions sensitizes peripheral axons to degeneration. It has been observed that in CMT the patients retain dominant and recessive mutations of LRSAM1 gene, which encodes most likely a defective protein. However, still the comprehensive molecular pathomechanism of LRSAM1 in neuronal functions and neurodegenerative diseases is not known. The current article systematically represents the molecular functions, nature and detailed characterization of LRSAM1 E3 ubiquitin ligase. Here, we review emerging molecular mechanisms of LRSAM1 linked with neurobiological functions, with a clear focus on the mechanism of neurodegeneration and also on other diseases. Better understanding of LRSAM1 neurobiological and intracellular functions may contribute to develop promising novel therapeutic approaches, which can also propose new lines of molecular beneficial targets for various neurodegenerative diseases.
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Affiliation(s)
- Ribhav Mishra
- Cellular and Molecular Neurobiology Unit, Indian Institute of Technology Jodhpur, Jodhpur, Rajasthan, 342037, India
| | - Arun Upadhyay
- Cellular and Molecular Neurobiology Unit, Indian Institute of Technology Jodhpur, Jodhpur, Rajasthan, 342037, India
| | - Vijay Kumar Prajapati
- Department of Biochemistry, School of Life Sciences, Central University of Rajasthan, NH-8 Bandarsindri, Ajmer, Rajasthan, 305817, India
| | - Rohan Dhiman
- Laboratory of Mycobacterial Immunology, Department of Life Science, National Institute of Technology, Rourkela, Odisha, 769008, India
| | - Krishna Mohan Poluri
- Department of Biotechnology, Indian Institute of Technology Roorkee, Roorkee, 247667, India
| | - Nihar Ranjan Jana
- School of Bioscience, Indian Institute of Technology, Kharagpur, Kharagpur, 721302, India
| | - Amit Mishra
- Cellular and Molecular Neurobiology Unit, Indian Institute of Technology Jodhpur, Jodhpur, Rajasthan, 342037, India.
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Finetti F, Cassioli C, Cianfanelli V, Onnis A, Paccagnini E, Kabanova A, Baldari CT. The intraflagellar transport protein IFT20 controls lysosome biogenesis by regulating the post-Golgi transport of acid hydrolases. Cell Death Differ 2019; 27:310-328. [PMID: 31142807 DOI: 10.1038/s41418-019-0357-y] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Revised: 04/16/2019] [Accepted: 05/14/2019] [Indexed: 01/08/2023] Open
Abstract
The assembly and function of the primary cilium depends on multimolecular intraflagellar transport (IFT) complexes that shuttle their cargo along the axonemal microtubules through their interaction with molecular motors. The IFT system has been moreover recently implicated in a reciprocal interplay between autophagy and ciliogenesis. We have previously reported that IFT20 and other components of the IFT complexes participate in the assembly of the immune synapse in the non-ciliated T cell, suggesting that other cellular processes regulated by the IFT system in ciliated cells, including autophagy, may be shared by cells lacking a cilium. Starting from the observation of a defect in autophagic clearance and an accumulation of lipid droplets in IFT20-deficient T cells, we show that IFT20 is required for lysosome biogenesis and function by controlling the lysosomal targeting of acid hydrolases. This function involves its ability to regulate the retrograde traffic of the cation-independent mannose-6-phosphate receptor (CI-MPR) to the trans-Golgi network, which is achieved by coupling recycling CI-MPRs to the microtubule motor dynein. Consistent with the lysosomal defect, an upregulation of the TFEB-dependent expression of the lysosomal gene network can be observed in IFT20-deficient cells, which is associated with defective tonic T-cell antigen receptor signaling and mTOR activity. We additionally show that the lysosome-related function of IFT20 extends to non-ciliated cells other than T cells, as well as to ciliated cells. Our findings provide the first evidence that a component of the IFT system that controls ciliogenesis is implicated in the biogenesis of lysosomes.
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Affiliation(s)
- Francesca Finetti
- Department of Life Sciences, University of Siena, Via Aldo Moro 2, 53100, Siena, Italy.
| | - Chiara Cassioli
- Department of Life Sciences, University of Siena, Via Aldo Moro 2, 53100, Siena, Italy
| | - Valentina Cianfanelli
- Cell Stress and Survival Unit, Danish Cancer Society Research Center, 2100, Copenhagen, Denmark
| | - Anna Onnis
- Department of Life Sciences, University of Siena, Via Aldo Moro 2, 53100, Siena, Italy
| | - Eugenio Paccagnini
- Department of Life Sciences, University of Siena, Via Aldo Moro 2, 53100, Siena, Italy
| | - Anna Kabanova
- Department of Life Sciences, University of Siena, Via Aldo Moro 2, 53100, Siena, Italy
| | - Cosima T Baldari
- Department of Life Sciences, University of Siena, Via Aldo Moro 2, 53100, Siena, Italy.
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24
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Autophagy-Related Proteins GABARAP and LC3B Label Structures of Similar Size but Different Shape in Super-Resolution Imaging. Molecules 2019; 24:molecules24091833. [PMID: 31086037 PMCID: PMC6539863 DOI: 10.3390/molecules24091833] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Revised: 05/07/2019] [Accepted: 05/07/2019] [Indexed: 12/19/2022] Open
Abstract
Subcellular structures containing autophagy-related proteins of the Atg8 protein family have been investigated with conventional wide-field fluorescence and single molecule localisation microscopy. Fusion proteins of GABARAP and LC3B, respectively, with EYFP were overexpressed in HEK293 cells. While size distributions of structures labelled by the two proteins were found to be similar, shape distributions appeared quite disparate, with EYFP-GABARAP favouring circular structures and elliptical structures being dominant for EYFP-LC3B. The latter also featured a nearly doubled fraction of U-shape structures. The experimental results point towards highly differential localisation of the two proteins, which appear to label structures representing distinct stages or even specific channels of vesicular trafficking pathways. Our data also demonstrate that the application of super-resolution techniques expands the possibilities of fluorescence-based methods in autophagy studies and in some cases can rectify conclusions obtained from conventional fluorescence microscopy with diffraction-limited resolution.
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25
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Sheu SJ, Chen JL, Bee YS, Lin SH, Shu CW. ERBB2-modulated ATG4B and autophagic cell death in human ARPE19 during oxidative stress. PLoS One 2019; 14:e0213932. [PMID: 30870514 PMCID: PMC6417729 DOI: 10.1371/journal.pone.0213932] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Accepted: 03/04/2019] [Indexed: 01/12/2023] Open
Abstract
Age-related macular degeneration (AMD) is an ocular disease with retinal degeneration. Retinal pigment epithelium (RPE) degeneration is mainly caused by long-term oxidative stress. Kinase activity could be either protective or detrimental to cells during oxidative stress; however, few reports have described the role of kinases in oxidative stress. In this study, high-throughput screening of kinome siRNA library revealed that erb-b2 receptor tyrosine-protein kinase 2 (ERBB2) knockdown reduced reactive oxygen species (ROS) production in ARPE-19 cells during oxidative stress. Silencing ERBB2 caused an elevation in microtubule associated protein light chain C3-II (MAP1LC3B-II/I) conversion and sequesterone (SQSTM)1 protein level. ERBB2 deprivation largely caused an increase in autophagy-regulating protease (ATG4B) expression, a protease that negatively recycles MAP1LC3-II at the fusion step between the autophagosome and lysosome, suggesting ERBB2 might modulate ATG4B for autophagy induction in oxidative stress-stimulated ARPE-19 cells. ERBB2 knockdown also caused an accumulation of nuclear factor erythroid 2-related factor 2 (NRF2) and enhanced its transcriptional activity. In addition, ERBB2 ablation or treatment with autophagy inhibitors reduced oxidative-induced cytotoxic effects in ARPE-19 cells. Furthermore, ERBB2 silencing had little or no additive effects in ATG5/7-deficient cells. Taken together, our results suggest that ERBB2 may play an important role in modulating autophagic RPE cell death during oxidative stress, and ERBB2 may be a potential target in AMD prevention.
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Affiliation(s)
- Shwu-Jiuan Sheu
- Department of Ophthalmology, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
- School of Medicine, National Yang-Ming University, Taipei, Taiwan
| | - Jiunn-Liang Chen
- Department of Ophthalmology, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
- School of Medicine, National Yang-Ming University, Taipei, Taiwan
- Department of Optometry, Shu-Zen Junior College of Medicine and Management, Kaohsiung, Taiwan
| | - Youn-Shen Bee
- Department of Ophthalmology, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
- Yuh-Ing Junior College of Health Care and Management, Kaohsiung, Taiwan
- National Defense Medical Center, Taipei, Taiwan
| | - Shi-Han Lin
- Department of Ophthalmology, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
| | - Chih-Wen Shu
- School of Medicine for International Students, I-Shou University, Kaohsiung, Taiwan
- Institute of Biomedical Sciences, National Sun Yat-Sen University, Kaohsiung, Taiwan
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26
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Shan Y, Sun S, Yang F, Shang N, Liu H. Dexmedetomidine protects the developing rat brain against the neurotoxicity wrought by sevoflurane: role of autophagy and Drp1-Bax signaling. Drug Des Devel Ther 2018; 12:3617-3624. [PMID: 30464393 PMCID: PMC6214411 DOI: 10.2147/dddt.s180343] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND The effect of sevoflurane on the nervous system is controversial. As an adjuvant anesthetic, dexmedetomidine has a protective role in various nerve-injury diseases. We investigated the effect of dexmedetomidine on injury to the developing brain induced by sevoflurane anesthesia, and if autophagy and mitochondrial damage are involved in the neuroprotective effects of dexmedetomidine. METHODS Pregnant rats on gestational day 20 were exposed to 3% sevoflurane for 4 hours. Saline and dexmedetomidine were injected intraperitoneally 15 minutes before exposure to sevoflurane or control gas. Bilateral hippocampi were harvested on postnatal day 1. Hippocampal morphology was observed by Nissl staining and expression of the microtubule-related protein LC3I/II, p62, Drp1, Bax, and Bcl2 were evaluated by Western blotting and immunohistochemistry. RESULTS Nissl staining showed that sevoflurane anesthesia during the third trimester caused neuronal damage to the hippocampi of rat pups. Western blotting and immunohistochemistry showed that pregnant rats exposed to sevoflurane during the third trimester led to pups having increased expression of LC3 and p62, suggesting that sevoflurane blocked autophagic flow in the hippocampus. Expression of Drp1 and Bax was increased after sevoflurane exposure, whereas Bcl2 expression was downregulated. All these effects were alleviated by pretreatment with dexmedetomidine. CONCLUSION Sevoflurane exposure during the third trimester caused neurological injury to rat pups. Autophagy and abnormalities in mitochondrial dynamics were involved in this neurotoxic process and were antagonized by dexmedetomidine.
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Affiliation(s)
- Yangyang Shan
- Department of Anesthesiology, Shengjing Hospital, China Medical University, Shenyang, 110004, China,
| | - Shiwei Sun
- Department of Anesthesiology, Shengjing Hospital, China Medical University, Shenyang, 110004, China,
| | - Fan Yang
- Department of Anesthesiology, Shengjing Hospital, China Medical University, Shenyang, 110004, China,
| | - Nan Shang
- Department of Respiration, No. 202 Hospital of PLA, Shenyang, 110003, China
| | - Hongtao Liu
- Department of Anesthesiology, Shengjing Hospital, China Medical University, Shenyang, 110004, China, ,Correspondence: Hongtao Liu, Department of Anesthesiology, Shengjing Hospital, China Medical University, 36 Sanhao Street, Heping District, Shenyang, 110004, China, Email
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27
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Chen Y, Sun HQ, Eichorst JP, Albanesi JP, Yin H, Mueller JD. Comobility of GABARAP and Phosphatidylinositol 4-Kinase 2A on Cytoplasmic Vesicles. Biochemistry 2018; 57:3556-3559. [PMID: 29792687 DOI: 10.1021/acs.biochem.8b00224] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
We previously reported that recruitment of the type IIA phosphatidylinositol 4-kinase (PI4K2A) to autophagosomes by GABARAP, a member of the Atg8 family of autophagy-related proteins, is important for autophagosome-lysosome fusion. Because both PI4K2A and GABARAP have also been implicated in the intracellular trafficking of plasma membrane receptors in the secretory/endocytic pathway, we characterized their interaction in cells under nonautophagic conditions. Fluorescence fluctuation spectroscopy measurements revealed that GABARAP exists predominantly as a cytosolic monomer in live cells, but is recruited to small cytoplasmic vesicles upon overexpression of PI4K2A. C-Terminal lipidation of GABARAP, which is essential for its autophagic activities, is not necessary for its recruitment to these PI4K2A-containing transport vesicles. However, a GABARAP truncation mutant lacking C-terminal residues 103-117 fails to bind to PI4K2A, is not recruited to cytoplasmic vesicles, and does not codistribute with PI4K2A on subcellular organelles. These observations suggest that the PI4K2A-GABARAP interaction plays a role in membrane trafficking both under autophagic and nonautophagic conditions.
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Affiliation(s)
- Yan Chen
- School of Physics and Astronomy , University of Minnesota , Minneapolis , Minnesota 55455 , United States
| | | | - John P Eichorst
- School of Physics and Astronomy , University of Minnesota , Minneapolis , Minnesota 55455 , United States
| | | | | | - Joachim D Mueller
- School of Physics and Astronomy , University of Minnesota , Minneapolis , Minnesota 55455 , United States
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28
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Kriegenburg F, Ungermann C, Reggiori F. Coordination of Autophagosome–Lysosome Fusion by Atg8 Family Members. Curr Biol 2018; 28:R512-R518. [DOI: 10.1016/j.cub.2018.02.034] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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