1
|
Yazaki E, Uehara T, Sakamoto H, Inagaki Y. Dinotoms possess two evolutionary distinct autophagy-related ubiquitin-like conjugation systems. Protist 2024; 175:126067. [PMID: 39341116 DOI: 10.1016/j.protis.2024.126067] [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: 03/11/2024] [Revised: 08/29/2024] [Accepted: 09/15/2024] [Indexed: 09/30/2024]
Abstract
Autophagy is an intracellular degradation mechanism by which cytoplasmic materials are delivered to and degraded in the lysosome-fused autophagosome (autolysosome) and proposed to have been established at an early stage of eukaryotic evolution. Dinoflagellates harboring endosymbiotic diatoms (so-called "dinotoms"), which retain their own nuclei and mitochondria in addition to plastids, have been investigated as an intermediate toward the full integration of a eukaryotic phototroph into the host-controlled organelle (i.e., plastid) through endosymbiosis. Pioneering studies systematically evaluated the degree of host governance on several metabolic pathways in the endosymbiotic diatoms (ESDs). However, little attention has been paid to the impact of the endosymbiotic lifestyle on the autophagy operated in the ESDs. In this study, we searched for ATG3, ATG4, ATG5, ATG7, ATG8, ATG10, and ATG12, which are required for autophagosome formation, in the RNA-seq data from dinotoms Durinskia baltica and Kryptoperidinium foliaceum. We detected two evolutionally distinct sets of the ATG proteins in the dinotom species, one affiliated with the dinoflagellate homologs and the other with the diatom homologs in phylogenetic analyses. The results suggest that the ATG proteins descended from the diatom taken up by the dinoflagellate host persist for autophagosome formation and, most likely, autophagy.
Collapse
Affiliation(s)
- Euki Yazaki
- Research Center for Advanced Analysis, National Agriculture and Food Research Organization, Tsukuba, Ibaraki, Japan; RIKEN iTHEMS, Wako, Saitama, Japan.
| | - Tadaaki Uehara
- Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Hirokazu Sakamoto
- Department of Infection and Host Defense, Graduate School of Medicine, Chiba University, Chiba, Chiba, Japan
| | - Yuji Inagaki
- Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan; Center for Computational Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan
| |
Collapse
|
2
|
Nie J, Ma S, Wu L, Li Y, Cao J, Li M, Mei P, Cooper PR, Li A, Pei D. SEC31a-ATG9a Interaction Mediates the Recruitment of COPII Vesicles for Autophagosome Formation. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024; 11:e2405127. [PMID: 39361436 PMCID: PMC11600210 DOI: 10.1002/advs.202405127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2024] [Revised: 07/28/2024] [Indexed: 10/05/2024]
Abstract
Autophagy plays an important role in determining stem-cell differentiation. During the osteogenic differentiation of mesenchymal stem cells (MSCs), autophagosome formation is upregulated but the reason is unknown. A long-standing quest in the autophagy field is to find the membrane origin of autophagosomes. In this study, cytoplasmic coat protein complex II (COPII) vesicles, endoplasmic reticulum-derived vesicles responsible for the transport of storage proteins to the Golgi, are demonstrated to be a critical source of osteoblastic autophagosomal membrane. A significant correlation between the number of COPII vesicle and the autophagy level is identified in the rat bone tissues. Disruption of COPII vesicles restrained osteogenesis and decreased the number and size of autophagosomes. SEC31a (an outer coat protein of COPII vesicle) is found to be vital to regulate COPII vesicle-dependent autophagosome formation via interacting with ATG9a of autophagosomal seed vesicles. The interference of Sec31a inhibited autophagosome formation and osteogenesis in vitro and in vivo. These results identified a novel mechanism of autophagosome formation in osteogenic differentiation of stem cells and identified SEC31a as a critical protein that mediates the interplay between COPII and ATG9a vesicles. These findings broaden the understanding of the regulatory mechanism in the osteogenic differentiation of MSCs.
Collapse
Affiliation(s)
- Jiaming Nie
- Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine ResearchCollege of StomatologyXi'an Jiaotong UniversityXi'anShaanxi710004China
| | - Shaoyang Ma
- Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine ResearchCollege of StomatologyXi'an Jiaotong UniversityXi'anShaanxi710004China
| | - Linyue Wu
- Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine ResearchCollege of StomatologyXi'an Jiaotong UniversityXi'anShaanxi710004China
| | - Ye Li
- Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine ResearchCollege of StomatologyXi'an Jiaotong UniversityXi'anShaanxi710004China
| | - Jiao Cao
- Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine ResearchCollege of StomatologyXi'an Jiaotong UniversityXi'anShaanxi710004China
| | - Meng Li
- Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine ResearchCollege of StomatologyXi'an Jiaotong UniversityXi'anShaanxi710004China
| | - Peter Mei
- Department of Oral SciencesFaculty of DentistryUniversity of OtagoDunedin9016New Zealand
| | - Paul R. Cooper
- Department of Oral SciencesFaculty of DentistryUniversity of OtagoDunedin9016New Zealand
| | - Ang Li
- Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine ResearchCollege of StomatologyXi'an Jiaotong UniversityXi'anShaanxi710004China
| | - Dandan Pei
- Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine ResearchCollege of StomatologyXi'an Jiaotong UniversityXi'anShaanxi710004China
| |
Collapse
|
3
|
Norell PN, Campisi D, Mohan J, Wollert T. Biogenesis of omegasomes and autophagosomes in mammalian autophagy. Biochem Soc Trans 2024; 52:2145-2155. [PMID: 39392358 PMCID: PMC11555699 DOI: 10.1042/bst20240015] [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] [Indexed: 10/12/2024]
Abstract
Autophagy is a highly conserved catabolic pathway that maintains cellular homeostasis by promoting the degradation of damaged or superfluous cytoplasmic material. A hallmark of autophagy is the generation of membrane cisternae that sequester autophagic cargo. Expansion of these structures allows cargo to be engulfed in a highly selective and exclusive manner. Cytotoxic stress or starvation induces the formation of autophagosomes that sequester bulk cytoplasm instead of selected cargo. This rather nonselective pathway is essential for maintaining vital cellular functions during adverse conditions and is thus a major stress response pathway. Both selective and nonselective autophagy rely on the same molecular machinery. However, due to the different nature of cargo to be sequestered, the involved molecular mechanisms are fundamentally different. Although intense research over the past decades has advanced our understanding of autophagy, fundamental questions remain to be addressed. This review will focus on molecular principles and open questions regarding the formation of omegasomes and phagophores in nonselective mammalian autophagy.
Collapse
Affiliation(s)
- Puck N. Norell
- Membrane Biochemistry and Transport, Institut Pasteur, Université de Paris, UMR3691 CNRS, 75015 Paris, France
| | - Daniele Campisi
- Membrane Biochemistry and Transport, Institut Pasteur, Université de Paris, UMR3691 CNRS, 75015 Paris, France
| | - Jagan Mohan
- Membrane Biochemistry and Transport, Institut Pasteur, Université de Paris, UMR3691 CNRS, 75015 Paris, France
| | - Thomas Wollert
- Membrane Biochemistry and Transport, Institut Pasteur, Université de Paris, UMR3691 CNRS, 75015 Paris, France
| |
Collapse
|
4
|
Liu J, Ma H, Wu Z, Ji Y, Liang Y. The Knowns and Unknowns of Membrane Features and Changes During Autophagosome-Lysosome/Vacuole Fusion. Int J Mol Sci 2024; 25:11160. [PMID: 39456939 PMCID: PMC11508585 DOI: 10.3390/ijms252011160] [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: 08/06/2024] [Revised: 10/04/2024] [Accepted: 10/14/2024] [Indexed: 10/28/2024] Open
Abstract
Autophagosome (AP)-lysosome/vacuole fusion is one of the hallmarks of macroautophagy. Membrane features and changes during the fusion process have mostly been described using two-dimensional (2D) models with one AP and one lysosome/vacuole. The outer membrane (OM) of a closed mature AP has been suggested to fuse with the lysosomal/vacuolar membrane. However, the descriptions in some studies for fusion-related issues are questionable or incomplete. The correct membrane features of APs and lysosomes/vacuoles are the prerequisite for describing the fusion process. We searched the literature for representative membrane features of AP-related structures based on electron microscopy (EM) graphs of both animal and yeast cells and re-evaluated the findings. We also summarized the main 2D models describing the membrane changes during AP-lysosome/vacuole fusion in the literature. We used three-dimensional (3D) models to characterize the known and unknown membrane changes during and after fusion of the most plausible 2D models. The actual situation is more complex, since multiple lysosomes may fuse with the same AP in mammalian cells, multiple APs may fuse with the same vacuole in yeast cells, and in some mutant cells, phagophores (unclosed APs) fuse with lysosomes/vacuoles. This review discusses the membrane features and highly dynamic changes during AP (phagophore)-lysosome/vacuole fusion. The resulting information will improve the understanding of AP-lysosome/vacuole fusion and direct the future research on AP-lysosome/vacuole fusion and regeneration.
Collapse
Affiliation(s)
| | | | | | | | - Yongheng Liang
- Key Laboratory of Agricultural Environmental Microbiology of Ministry of Agriculture and Rural Affairs, College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China; (J.L.); (H.M.); (Z.W.); (Y.J.)
| |
Collapse
|
5
|
Chung T, Choi YE, Song K, Jung H. How coat proteins shape autophagy in plant cells. PLANT PHYSIOLOGY 2024:kiae426. [PMID: 39259569 DOI: 10.1093/plphys/kiae426] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2024] [Accepted: 08/07/2024] [Indexed: 09/13/2024]
Abstract
Autophagy is a membrane trafficking pathway through which eukaryotic cells target their own cytoplasmic constituents for degradation in the lytic compartment. Proper biogenesis of autophagic organelles requires a conserved set of autophagy-related (ATG) proteins and their interacting factors, such as signalling phospholipid phosphatidylinositol 3-phosphate (PI3P) and coat complex II (COPII). The COPII machinery, which was originally identified as a membrane coat involved in the formation of vesicles budding from the endoplasmic reticulum, contributes to the initiation of autophagic membrane formation in yeast, metazoan, and plant cells; however, the exact mechanisms remain elusive. Recent studies using the plant model species Arabidopsis thaliana have revealed that plant-specific PI3P effectors are involved in autophagy. The PI3P effector FYVE2 interacts with the conserved PI3P effector ATG18 and with COPII components, indicating an additional role for the COPII machinery in the later stages of autophagosome biogenesis. In this Update, we examined recent research on plant autophagosome biogenesis and proposed working models on the functions of the COPII machinery in autophagy, including its potential roles in stabilizing membrane curvature and sealing the phagophore.
Collapse
Affiliation(s)
- Taijoon Chung
- Department of Biological Sciences, Pusan National University, Busan, 46241, Republic of Korea
- Institute of Systems Biology, Pusan National University, Busan, 46241, Republic of Korea
| | - Ye Eun Choi
- Department of Biological Sciences, Pusan National University, Busan, 46241, Republic of Korea
| | - Kyoungjun Song
- Department of Biological Sciences, Pusan National University, Busan, 46241, Republic of Korea
| | - Hyera Jung
- Department of Biological Sciences, Pusan National University, Busan, 46241, Republic of Korea
- Institute of Systems Biology, Pusan National University, Busan, 46241, Republic of Korea
| |
Collapse
|
6
|
Li X, Zheng J, Su J, Wang L, Luan L, Wang T, Bai F, Zhong Q, Gong Q. Myotubularin 2 interacts with SEC23A and negatively regulates autophagy at ER exit sites in Arabidopsis. Autophagy 2024:1-19. [PMID: 39177202 DOI: 10.1080/15548627.2024.2394302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2024] [Revised: 08/11/2024] [Accepted: 08/15/2024] [Indexed: 08/24/2024] Open
Abstract
Starvation- or stress-induced phosphatidylinositol 3-phosphate (PtdIns3P/PI3P) production at the endoplasmic reticulum (ER) subdomains organizes phagophore assembly and autophagosome formation. Coat protein complex II (COPII) vesicles budding from ER exit site (ERES) also contribute to autophagosome formation. Whether any PtdIns3P phosphatase functions at ERES to inhibit macroautophagy/autophagy is unknown. Here we report Myotubularin 2 (MTM2) of Arabidopsis as a PtdIns3P phosphatase that localizes to ERES and negatively regulates autophagy. MTM2 binds PtdIns3P with its PH-GRAM domain in vitro and acts toward PtdIns3P in vivo. Transiently expressed MTM2 colocalizes with ATG14b, a subunit of the phosphatidylinositol 3-kinase (PtdIns3K) complex, and overexpression of MTM2 blocks autophagic flux and causes over-accumulation of ATG18a, ATG5, and ATG8a. The mtm2 mutant has higher levels of autophagy and is more tolerant to starvation, whereas MTM2 overexpression leads to reduced autophagy and sensitivity to starvation. The phenotypes of mtm2 are suppressed by ATG2 mutation, suggesting that MTM2 acts upstream of ATG2. Importantly, MTM2 does not affect the endosomal functions of PtdIns3P. Instead, MTM2 specifically colocalizes with COPII coat proteins and is cradled by the ERES-defining protein SEC16. MTM2 interacts with SEC23A with its phosphatase domain and inhibits COPII-mediated protein secretion. Finally, a role for MTM2 in salt stress response is uncovered. mtm2 resembles the halophyte Thellungiella salsuginea in its efficient vacuolar compartmentation of Na+, maintenance of chloroplast integrity, and timely regulation of autophagy-related genes. Our findings reveal a balance between PtdIns3P synthesis and turnover in autophagosome formation, and provide a new link between autophagy and COPII function.Abbreviations: ATG: autophagy related; BFA: brefeldin A; BiFC: bimolecular fluorescence complementation; CHX: cycloheximide; ConA: concanamycin A; COPII: coat protein complex II; ER: endoplasmic reticulum; ERES: ER exit site; MS: Murashige and Skoog; MTM: myotubularin; MVB: multivesicular body; PAS: phagophore assembly site; PI: phosphoinositide; TEM: transmission electron microscopy; WT: wild-type.
Collapse
Affiliation(s)
- Xinjing Li
- State Key Laboratory of Microbial Metabolism & Joint International Research Laboratory of Metabolic and Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, P. R. China
| | - Jing Zheng
- Department of Plant Biology and Ecology, College of Life Sciences, Nankai University, Tianjin, P. R. China
| | - Jing Su
- Department of Plant Biology and Ecology, College of Life Sciences, Nankai University, Tianjin, P. R. China
| | - Lin Wang
- Shanghai Institute for Advanced Immunochemical Studies, School of Life Science and Technology, ShanghaiTech University, Shanghai, P. R. China
| | - Lin Luan
- Department of Plant Biology and Ecology, College of Life Sciences, Nankai University, Tianjin, P. R. China
| | - Taotao Wang
- State Key Laboratory of Microbial Metabolism & Joint International Research Laboratory of Metabolic and Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, P. R. China
| | - Fang Bai
- Shanghai Institute for Advanced Immunochemical Studies, School of Life Science and Technology, ShanghaiTech University, Shanghai, P. R. China
| | - Qing Zhong
- Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Department of Pathophysiology, Shanghai Jiao Tong University School of Medicine, Shanghai, P. R. China
| | - Qingqiu Gong
- State Key Laboratory of Microbial Metabolism & Joint International Research Laboratory of Metabolic and Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, P. R. China
| |
Collapse
|
7
|
Holzer E, Martens S, Tulli S. The Role of ATG9 Vesicles in Autophagosome Biogenesis. J Mol Biol 2024; 436:168489. [PMID: 38342428 DOI: 10.1016/j.jmb.2024.168489] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Revised: 02/02/2024] [Accepted: 02/07/2024] [Indexed: 02/13/2024]
Abstract
Autophagy mediates the degradation and recycling of cellular material in the lysosomal system. Dysfunctional autophagy is associated with a plethora of diseases including uncontrolled infections, cancer and neurodegeneration. In macroautophagy (hereafter autophagy) this material is encapsulated in double membrane vesicles, the autophagosomes, which form upon induction of autophagy. The precursors to autophagosomes, referred to as phagophores, first appear as small flattened membrane cisternae, which gradually enclose the cargo material as they grow. The assembly of phagophores during autophagy initiation has been a major subject of investigation over the past decades. A special focus has been ATG9, the only conserved transmembrane protein among the core machinery. The majority of ATG9 localizes to small Golgi-derived vesicles. Here we review the recent advances and breakthroughs regarding our understanding of how ATG9 and the vesicles it resides in serve to assemble the autophagy machinery and to establish membrane contact sites for autophagosome biogenesis. We also highlight open questions in the field that need to be addressed in the years to come.
Collapse
Affiliation(s)
- Elisabeth Holzer
- Max Perutz Labs, Vienna BioCenter Campus (VBC), Vienna, Austria; University of Vienna, Max Perutz Labs, Department of Biochemistry and Cell Biology, Vienna, Austria; Vienna BioCenter PhD Program, Doctoral School of the University of Vienna and Medical University of Vienna, Campus-Vienna-Biocenter 1, Vienna, Austria.
| | - Sascha Martens
- Max Perutz Labs, Vienna BioCenter Campus (VBC), Vienna, Austria; University of Vienna, Max Perutz Labs, Department of Biochemistry and Cell Biology, Vienna, Austria.
| | - Susanna Tulli
- Max Perutz Labs, Vienna BioCenter Campus (VBC), Vienna, Austria; University of Vienna, Max Perutz Labs, Department of Biochemistry and Cell Biology, Vienna, Austria.
| |
Collapse
|
8
|
Zhang H, Zhang D, Li L, Willard B, Runge KW. In Vivo Proximity Labeling Identifies a New Function for the Lifespan and Autophagy-regulating Kinase Pef1, an Ortholog of Human Cdk5. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.12.598664. [PMID: 38915521 PMCID: PMC11195251 DOI: 10.1101/2024.06.12.598664] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/26/2024]
Abstract
Cdk5 is a highly-conserved, noncanonical cell division kinase important to the terminal differentiation of mammalian cells in multiple organ systems. We previously identified Pef1, the Schizosaccharomyces pombe ortholog of cdk5, as regulator of chronological lifespan. To reveal the processes impacted by Pef1, we developed APEX2-biotin phenol-mediated proximity labeling in S. pombe. Efficient labeling required a short period of cell wall digestion and eliminating glucose and nitrogen sources from the medium. We identified 255 high-confidence Pef1 neighbors in growing cells and a novel Pef1-interacting partner, the DNA damage response protein Rad24. The Pef1-Rad24 interaction was validated by reciprocal proximity labeling and co-immunoprecipitation. Eliminating Pef1 partially rescued the DNA damage sensitivity of cells lacking Rad24. To monitor how Pef1 neighbors change under different conditions, cells induced for autophagy were labeled and 177 high-confidence Pef1 neighbors were identified. Gene ontology (GO) analysis of the Pef1 neighbors identified proteins participating in processes required for autophagosome expansion including regulation of actin dynamics and vesicle-mediated transport. Some of these proteins were identified in both exponentially growing and autophagic cells. Pef1-APEX2 proximity labeling therefore identified a new Pef1 function in modulating the DNA damage response and candidate processes that Pef1 and other cdk5 orthologs may regulate.
Collapse
Affiliation(s)
- Haitao Zhang
- Department of Inflammation and Immunity, Lerner Research Institute, Cleveland Clinic Lerner College of Medicine at CWRU
| | - Dongmei Zhang
- Lerner Research Institute Proteomics Core and Case Comprehensive Cancer Center Cleveland Clinic Lerner College of Medicine at CWRU
| | - Ling Li
- Lerner Research Institute Proteomics Core and Case Comprehensive Cancer Center Cleveland Clinic Lerner College of Medicine at CWRU
| | - Belinda Willard
- Lerner Research Institute Proteomics Core and Case Comprehensive Cancer Center Cleveland Clinic Lerner College of Medicine at CWRU
| | - Kurt W. Runge
- Department of Inflammation and Immunity, Lerner Research Institute, Cleveland Clinic Lerner College of Medicine at CWRU
- Department of Genomics and Genome Sciences, Case Western Reserve University School of Medicine
| |
Collapse
|
9
|
Liao YC, Pang S, Li WP, Shtengel G, Choi H, Schaefer K, Xu CS, Lippincott-Schwartz J. COPII with ALG2 and ESCRTs control lysosome-dependent microautophagy of ER exit sites. Dev Cell 2024; 59:1410-1424.e4. [PMID: 38593803 DOI: 10.1016/j.devcel.2024.03.027] [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: 06/10/2022] [Revised: 09/23/2023] [Accepted: 03/12/2024] [Indexed: 04/11/2024]
Abstract
Endoplasmic reticulum exit sites (ERESs) are tubular outgrowths of endoplasmic reticulum that serve as the earliest station for protein sorting and export into the secretory pathway. How these structures respond to different cellular conditions remains unclear. Here, we report that ERESs undergo lysosome-dependent microautophagy when Ca2+ is released by lysosomes in response to nutrient stressors such as mTOR inhibition or amino acid starvation in mammalian cells. Targeting and uptake of ERESs into lysosomes were observed by super-resolution live-cell imaging and focus ion beam scanning electron microscopy (FIB-SEM). The mechanism was ESCRT dependent and required ubiquitinated SEC31, ALG2, and ALIX, with a knockout of ALG2 or function-blocking mutations of ALIX preventing engulfment of ERESs by lysosomes. In vitro, reconstitution of the pathway was possible using lysosomal lipid-mimicking giant unilamellar vesicles and purified recombinant components. Together, these findings demonstrate a pathway of lysosome-dependent ERES microautophagy mediated by COPII, ALG2, and ESCRTS induced by nutrient stress.
Collapse
Affiliation(s)
| | - Song Pang
- HHMI Janelia Research Campus, Ashburn, VA, USA; Yale School of Medicine, New Haven, CT, USA
| | - Wei-Ping Li
- HHMI Janelia Research Campus, Ashburn, VA, USA
| | | | - Heejun Choi
- HHMI Janelia Research Campus, Ashburn, VA, USA
| | | | - C Shan Xu
- HHMI Janelia Research Campus, Ashburn, VA, USA; Yale School of Medicine, New Haven, CT, USA
| | | |
Collapse
|
10
|
Anglès F, Gupta V, Wang C, Balch WE. COPII cage assembly factor Sec13 integrates information flow regulating endomembrane function in response to human variation. Sci Rep 2024; 14:10160. [PMID: 38698045 PMCID: PMC11065896 DOI: 10.1038/s41598-024-60687-2] [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: 07/12/2023] [Accepted: 04/26/2024] [Indexed: 05/05/2024] Open
Abstract
How information flow is coordinated for managing transit of 1/3 of the genome through endomembrane pathways by the coat complex II (COPII) system in response to human variation remains an enigma. By examining the interactome of the COPII cage-assembly component Sec13, we show that it is simultaneously associated with multiple protein complexes that facilitate different features of a continuous program of chromatin organization, transcription, translation, trafficking, and degradation steps that are differentially sensitive to Sec13 levels. For the trafficking step, and unlike other COPII components, reduction of Sec13 expression decreased the ubiquitination and degradation of wild-type (WT) and F508del variant cargo protein cystic fibrosis transmembrane conductance regulator (CFTR) leading to a striking increase in fold stability suggesting that the events differentiating export from degradation are critically dependent on COPII cage assembly at the ER Golgi intermediate compartment (ERGIC) associated recycling and degradation step linked to COPI exchange. Given Sec13's multiple roles in protein complex assemblies that change in response to its expression, we suggest that Sec13 serves as an unanticipated master regulator coordinating information flow from the genome to the proteome to facilitate spatial covariant features initiating and maintaining design and function of membrane architecture in response to human variation.
Collapse
Affiliation(s)
- Frédéric Anglès
- Department of Molecular Medicine, The Scripps Research Institute, 10550 North Torrey Pines Rd, La Jolla, CA, 92037, USA
| | - Vijay Gupta
- Department of Molecular Medicine, The Scripps Research Institute, 10550 North Torrey Pines Rd, La Jolla, CA, 92037, USA
| | - Chao Wang
- Department of Molecular Medicine, The Scripps Research Institute, 10550 North Torrey Pines Rd, La Jolla, CA, 92037, USA
| | - William E Balch
- Department of Molecular Medicine, The Scripps Research Institute, 10550 North Torrey Pines Rd, La Jolla, CA, 92037, USA.
| |
Collapse
|
11
|
Ortega MA, Fraile-Martinez O, de Leon-Oliva D, Boaru DL, Lopez-Gonzalez L, García-Montero C, Alvarez-Mon MA, Guijarro LG, Torres-Carranza D, Saez MA, Diaz-Pedrero R, Albillos A, Alvarez-Mon M. Autophagy in Its (Proper) Context: Molecular Basis, Biological Relevance, Pharmacological Modulation, and Lifestyle Medicine. Int J Biol Sci 2024; 20:2532-2554. [PMID: 38725847 PMCID: PMC11077378 DOI: 10.7150/ijbs.95122] [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: 02/06/2024] [Accepted: 04/04/2024] [Indexed: 05/12/2024] Open
Abstract
Autophagy plays a critical role in maintaining cellular homeostasis and responding to various stress conditions by the degradation of intracellular components. In this narrative review, we provide a comprehensive overview of autophagy's cellular and molecular basis, biological significance, pharmacological modulation, and its relevance in lifestyle medicine. We delve into the intricate molecular mechanisms that govern autophagy, including macroautophagy, microautophagy and chaperone-mediated autophagy. Moreover, we highlight the biological significance of autophagy in aging, immunity, metabolism, apoptosis, tissue differentiation and systemic diseases, such as neurodegenerative or cardiovascular diseases and cancer. We also discuss the latest advancements in pharmacological modulation of autophagy and their potential implications in clinical settings. Finally, we explore the intimate connection between lifestyle factors and autophagy, emphasizing how nutrition, exercise, sleep patterns and environmental factors can significantly impact the autophagic process. The integration of lifestyle medicine into autophagy research opens new avenues for promoting health and longevity through personalized interventions.
Collapse
Affiliation(s)
- Miguel A Ortega
- Department of Medicine and Medical Specialities, Faculty of Medicine and Health Sciences, University of Alcalá, 28801 Alcala de Henares, Spain
- Ramón y Cajal Institute of Sanitary Research (IRYCIS), 28034 Madrid, Spain
| | - Oscar Fraile-Martinez
- Department of Medicine and Medical Specialities, Faculty of Medicine and Health Sciences, University of Alcalá, 28801 Alcala de Henares, Spain
- Ramón y Cajal Institute of Sanitary Research (IRYCIS), 28034 Madrid, Spain
| | - Diego de Leon-Oliva
- Department of Medicine and Medical Specialities, Faculty of Medicine and Health Sciences, University of Alcalá, 28801 Alcala de Henares, Spain
- Ramón y Cajal Institute of Sanitary Research (IRYCIS), 28034 Madrid, Spain
| | - Diego Liviu Boaru
- Department of Medicine and Medical Specialities, Faculty of Medicine and Health Sciences, University of Alcalá, 28801 Alcala de Henares, Spain
- Ramón y Cajal Institute of Sanitary Research (IRYCIS), 28034 Madrid, Spain
| | - Laura Lopez-Gonzalez
- Ramón y Cajal Institute of Sanitary Research (IRYCIS), 28034 Madrid, Spain
- Department of Surgery, Medical and Social Sciences, Faculty of Medicine and Health Sciences, University of Alcalá, 28801 Alcala de Henares, Spain
| | - Cielo García-Montero
- Department of Medicine and Medical Specialities, Faculty of Medicine and Health Sciences, University of Alcalá, 28801 Alcala de Henares, Spain
- Ramón y Cajal Institute of Sanitary Research (IRYCIS), 28034 Madrid, Spain
| | - Miguel Angel Alvarez-Mon
- Department of Medicine and Medical Specialities, Faculty of Medicine and Health Sciences, University of Alcalá, 28801 Alcala de Henares, Spain
- Ramón y Cajal Institute of Sanitary Research (IRYCIS), 28034 Madrid, Spain
| | - Luis G Guijarro
- Ramón y Cajal Institute of Sanitary Research (IRYCIS), 28034 Madrid, Spain
- Unit of Biochemistry and Molecular Biology, Department of System Biology (CIBEREHD), University of Alcalá, 28801 Alcala de Henares, Spain
| | - Diego Torres-Carranza
- Department of Medicine and Medical Specialities, Faculty of Medicine and Health Sciences, University of Alcalá, 28801 Alcala de Henares, Spain
- Ramón y Cajal Institute of Sanitary Research (IRYCIS), 28034 Madrid, Spain
| | - Miguel A Saez
- Department of Medicine and Medical Specialities, Faculty of Medicine and Health Sciences, University of Alcalá, 28801 Alcala de Henares, Spain
- Ramón y Cajal Institute of Sanitary Research (IRYCIS), 28034 Madrid, Spain
- Pathological Anatomy Service, Central University Hospital of Defence-UAH Madrid, 28801 Alcala de Henares, Spain
| | - Raul Diaz-Pedrero
- Ramón y Cajal Institute of Sanitary Research (IRYCIS), 28034 Madrid, Spain
- Department of Surgery, Medical and Social Sciences, Faculty of Medicine and Health Sciences, University of Alcalá, 28801 Alcala de Henares, Spain
- Department of General and Digestive Surgery, Príncipe de Asturias Universitary Hospital, 28805 Alcala de Henares, Spain
| | - Agustin Albillos
- Department of Medicine and Medical Specialities, Faculty of Medicine and Health Sciences, University of Alcalá, 28801 Alcala de Henares, Spain
- Ramón y Cajal Institute of Sanitary Research (IRYCIS), 28034 Madrid, Spain
| | - Melchor Alvarez-Mon
- Department of Medicine and Medical Specialities, Faculty of Medicine and Health Sciences, University of Alcalá, 28801 Alcala de Henares, Spain
- Ramón y Cajal Institute of Sanitary Research (IRYCIS), 28034 Madrid, Spain
- Immune System Diseases-Rheumatology, Oncology Service an Internal Medicine (CIBEREHD), Príncipe de Asturias University Hospital, 28806 Alcala de Henares, Spain
| |
Collapse
|
12
|
Mayer J, Boeck D, Werner M, Frankenhauser D, Geley S, Farhan H, Shimozawa M, Nilsson P. Inhibition of Autophagy Alters Intracellular Transport of APP Resulting in Increased APP Processing. Traffic 2024; 25:e12934. [PMID: 38613404 DOI: 10.1111/tra.12934] [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: 09/24/2023] [Revised: 03/03/2024] [Accepted: 03/19/2024] [Indexed: 04/14/2024]
Abstract
Alzheimer's disease (AD) pathology is characterized by amyloid beta (Aβ) plaques and dysfunctional autophagy. Aβ is generated by sequential proteolytic cleavage of amyloid precursor protein (APP), and the site of intracellular APP processing is highly debated, which may include autophagosomes. Here, we investigated the involvement of autophagy, including the role of ATG9 in APP intracellular trafficking and processing by applying the RUSH system, which allows studying the transport of fluorescently labeled mCherry-APP-EGFP in a systematic way, starting from the endoplasmic reticulum. HeLa cells, expressing the RUSH mCherry-APP-EGFP system, were investigated by live cell imaging, immunofluorescence, and Western blot. We found that mCherry-APP-EGFP passed through the Golgi faster in ATG9 knockout cells. Furthermore, ATG9 deletion shifted mCherry-APP-EGFP from early endosomes and lysosomes toward the plasma membrane concomitant with reduced endocytosis. Importantly, this alteration in mCherry-APP-EGFP transport resulted in increased secreted mCherry-soluble APP and C-terminal fragment-EGFP. These effects were also phenocopied by pharmacological inhibition of ULK1, indicating that autophagy is regulating the intracellular trafficking and processing of APP. These findings contribute to the understanding of the role of autophagy in APP metabolism and could potentially have implications for new therapeutic approaches for AD.
Collapse
Affiliation(s)
- Johanna Mayer
- Department of Neurobiology, Care Sciences and Society, Division of Neurogeriatrics, Karolinska Institutet, Solna, Sweden
| | - Dominik Boeck
- Department of Neurobiology, Care Sciences and Society, Division of Neurogeriatrics, Karolinska Institutet, Solna, Sweden
- Institute of Molecular Neurogenetics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Michelle Werner
- Department of Neurobiology, Care Sciences and Society, Division of Neurogeriatrics, Karolinska Institutet, Solna, Sweden
| | | | - Stephan Geley
- Institute of Pathophysiology, Innsbruck Medical University, Innsbruck, Austria
| | - Hesso Farhan
- Institute of Pathophysiology, Innsbruck Medical University, Innsbruck, Austria
| | - Makoto Shimozawa
- Department of Neurobiology, Care Sciences and Society, Division of Neurogeriatrics, Karolinska Institutet, Solna, Sweden
| | - Per Nilsson
- Department of Neurobiology, Care Sciences and Society, Division of Neurogeriatrics, Karolinska Institutet, Solna, Sweden
| |
Collapse
|
13
|
Muramoto M, Mineoka N, Fukuda K, Kuriyama S, Masatani T, Fujita A. Coordinated regulation of phosphatidylinositol 4-phosphate and phosphatidylserine levels by Osh4p and Osh5p is an essential regulatory mechanism in autophagy. BIOCHIMICA ET BIOPHYSICA ACTA. BIOMEMBRANES 2024; 1866:184308. [PMID: 38437942 DOI: 10.1016/j.bbamem.2024.184308] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2023] [Revised: 01/26/2024] [Accepted: 02/26/2024] [Indexed: 03/06/2024]
Abstract
Macroautophagy (hereafter autophagy) is an intracellular degradative pathway in budding yeast cells. Certain lipid types play essential roles in autophagy; yet the precise mechanisms regulating lipid composition during autophagy remain unknown. Here, we explored the role of the Osh family proteins in the modulating lipid composition during autophagy in budding yeast. Our results showed that osh1-osh7∆ deletions lead to autophagic dysfunction, with impaired GFP-Atg8 processing and the absence of autophagosomes and autophagic bodies in the cytosol and vacuole, respectively. Freeze-fracture electron microscopy (EM) revealed elevated phosphatidylinositol 4-phosphate (PtdIns(4)P) levels in cytoplasmic and luminal leaflets of autophagic bodies and vacuolar membranes in all deletion mutants. Phosphatidylserine (PtdSer) levels were significantly decreased in the autophagic bodies and vacuolar membranes in osh4∆ and osh5∆ mutants, whereas no significant changes were observed in other osh deletion mutants. Furthermore, we identified defects in autophagic processes in the osh4∆ and osh5∆ mutants, including rare autophagosome formation in the osh5∆ mutant and accumulation of autophagic bodies in the vacuole in the osh4∆ mutant, even in the absence of the proteinase inhibitor PMSF. These findings suggest that Osh4p and Osh5p play crucial roles in the transport of PtdSer to autophagic bodies and autophagosome membranes, respectively. The precise control of lipid composition in the membranes of autophagosomes and autophagic bodies by Osh4p and Osh5p represents an important regulatory mechanism in autophagy.
Collapse
Affiliation(s)
- Moe Muramoto
- Department of Molecular and Cell Biology and Biochemistry, Basic Veterinary Science, Faculty of Veterinary Medicine, Kagoshima University, Korimoto 1-21-24, Kagoshima 890-0065, Japan
| | - Nanaru Mineoka
- Department of Molecular and Cell Biology and Biochemistry, Basic Veterinary Science, Faculty of Veterinary Medicine, Kagoshima University, Korimoto 1-21-24, Kagoshima 890-0065, Japan
| | - Kayoko Fukuda
- Department of Molecular and Cell Biology and Biochemistry, Basic Veterinary Science, Faculty of Veterinary Medicine, Kagoshima University, Korimoto 1-21-24, Kagoshima 890-0065, Japan
| | - Sayuri Kuriyama
- Department of Molecular and Cell Biology and Biochemistry, Basic Veterinary Science, Faculty of Veterinary Medicine, Kagoshima University, Korimoto 1-21-24, Kagoshima 890-0065, Japan
| | - Tatsunori Masatani
- Laboratory of Zoonotic Diseases, Faculty of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan; Center for One Medicine Innovative Translational Research (COMIT), Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan
| | - Akikazu Fujita
- Department of Molecular and Cell Biology and Biochemistry, Basic Veterinary Science, Faculty of Veterinary Medicine, Kagoshima University, Korimoto 1-21-24, Kagoshima 890-0065, Japan.
| |
Collapse
|
14
|
Yagyu M, Yoshimoto K. New insights into plant autophagy: molecular mechanisms and roles in development and stress responses. JOURNAL OF EXPERIMENTAL BOTANY 2024; 75:1234-1251. [PMID: 37978884 DOI: 10.1093/jxb/erad459] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2023] [Accepted: 11/17/2023] [Indexed: 11/19/2023]
Abstract
Autophagy is an evolutionarily conserved eukaryotic intracellular degradation process. Although the molecular mechanisms of plant autophagy share similarities with those in yeast and mammals, certain unique mechanisms have been identified. Recent studies have highlighted the importance of autophagy during vegetative growth stages as well as in plant-specific developmental processes, such as seed development, germination, flowering, and somatic reprogramming. Autophagy enables plants to adapt to and manage severe environmental conditions, such as nutrient starvation, high-intensity light stress, and heat stress, leading to intracellular remodeling and physiological changes in response to stress. In the past, plant autophagy research lagged behind similar studies in yeast and mammals; however, recent advances have greatly expanded our understanding of plant-specific autophagy mechanisms and functions. This review summarizes current knowledge and latest research findings on the mechanisms and roles of plant autophagy with the objective of improving our understanding of this vital process in plants.
Collapse
Affiliation(s)
- Mako Yagyu
- Department of Life Sciences, School of Agriculture, Meiji University, 1-1-1 Higashimita, Tama-ku, Kawasaki, Kanagawa, 214-8571, Japan
- Life Sciences Program, Graduate School of Agriculture, Meiji University, 1-1-1 Higashimita, Tama-ku, Kawasaki, Kanagawa, 214-8571, Japan
| | - Kohki Yoshimoto
- Department of Life Sciences, School of Agriculture, Meiji University, 1-1-1 Higashimita, Tama-ku, Kawasaki, Kanagawa, 214-8571, Japan
- Life Sciences Program, Graduate School of Agriculture, Meiji University, 1-1-1 Higashimita, Tama-ku, Kawasaki, Kanagawa, 214-8571, Japan
| |
Collapse
|
15
|
Kotani T, Yasuda Y, Nakatogawa H. Molecular Mechanism of Autophagy, Cytoplasmic Zoning by Lipid Membranes. J Biochem 2024; 175:155-165. [PMID: 37983716 DOI: 10.1093/jb/mvad099] [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: 08/31/2023] [Revised: 11/02/2023] [Accepted: 11/06/2023] [Indexed: 11/22/2023] Open
Abstract
Autophagy is a highly conserved intracellular degradation mechanism. The most distinctive feature of autophagy is the formation of double-membrane structures called autophagosomes, which compartmentalize portions of the cytoplasm. The outer membrane of the autophagosome fuses with the vacuolar/lysosomal membrane, leading to the degradation of the contents of the autophagosome. Approximately 30 years have passed since the identification of autophagy-related (ATG) genes and Atg proteins essential for autophagosome formation, and the primary functions of these Atg proteins have been elucidated. These achievements have significantly advanced our understanding of the mechanism of autophagosome formation. This article summarizes our current knowledge on how the autophagosome precursor is generated, and how the membrane expands and seals to complete the autophagosome.
Collapse
Affiliation(s)
- Tetsuya Kotani
- Cell Biology Center, Institute of Innovative Research, Tokyo Institute of Technology, S2-14 4259 Nagatsuta-cho, Midori-ku, Yokohama, Kanagawa 226-8501, Japan
| | - Yuri Yasuda
- School of Life Science and Technology, Tokyo Institute of Technology, S2-14 4259 Nagatsuta-cho, Midori-ku, Yokohama, Kanagawa 226-8501, Japan
| | - Hitoshi Nakatogawa
- Cell Biology Center, Institute of Innovative Research, Tokyo Institute of Technology, S2-14 4259 Nagatsuta-cho, Midori-ku, Yokohama, Kanagawa 226-8501, Japan
- School of Life Science and Technology, Tokyo Institute of Technology, S2-14 4259 Nagatsuta-cho, Midori-ku, Yokohama, Kanagawa 226-8501, Japan
| |
Collapse
|
16
|
Ma L, Han T, Zhan YA. Mechanism and role of mitophagy in the development of severe infection. Cell Death Discov 2024; 10:88. [PMID: 38374038 PMCID: PMC10876966 DOI: 10.1038/s41420-024-01844-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2023] [Revised: 01/31/2024] [Accepted: 02/01/2024] [Indexed: 02/21/2024] Open
Abstract
Mitochondria produce adenosine triphosphate and potentially contribute to proinflammatory responses and cell death. Mitophagy, as a conservative phenomenon, scavenges waste mitochondria and their components in the cell. Recent studies suggest that severe infections develop alongside mitochondrial dysfunction and mitophagy abnormalities. Restoring mitophagy protects against excessive inflammation and multiple organ failure in sepsis. Here, we review the normal mitophagy process, its interaction with invading microorganisms and the immune system, and summarize the mechanism of mitophagy dysfunction during severe infection. We highlight critical role of normal mitophagy in preventing severe infection.
Collapse
Affiliation(s)
- Lixiu Ma
- Department of Respiratory and Critical Care Medicine, the 1st Affiliated Hospital, Jiangxi Medical College, Nanchang University, Nanchang, 330006, Jiangxi, China
| | - Tianyu Han
- Jiangxi Institute of Respiratory Disease, the 1st Affiliated Hospital, Jiangxi Medical College, Nanchang University, Nanchang, 330006, Jiangxi, China
| | - Yi-An Zhan
- Department of Respiratory and Critical Care Medicine, the 1st Affiliated Hospital, Jiangxi Medical College, Nanchang University, Nanchang, 330006, Jiangxi, China.
| |
Collapse
|
17
|
Nie J, Ma S, Zhang Y, Yu S, Yang J, Li A, Pei D. COPI Vesicle Disruption Inhibits Mineralization via mTORC1-Mediated Autophagy. Int J Mol Sci 2023; 25:339. [PMID: 38203512 PMCID: PMC10779376 DOI: 10.3390/ijms25010339] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Revised: 12/21/2023] [Accepted: 12/22/2023] [Indexed: 01/12/2024] Open
Abstract
Bone mineralization is a sophisticated regulated process composed of crystalline calcium phosphate and collagen fibril. Autophagy, an evolutionarily conserved degradation system, whereby double-membrane vesicles deliver intracellular macromolecules and organelles to lysosomes for degradation, has recently been shown to play an essential role in mineralization. However, the formation of autophagosomes in mineralization remains to be determined. Here, we show that Coat Protein Complex I (COPI), responsible for Golgi-to-ER transport, plays a pivotal role in autophagosome formation in mineralization. COPI vesicles were increased after osteoinduction, and COPI vesicle disruption impaired osteogenesis. Mechanistically, COPI regulates autophagy activity via the mTOR complex 1 (mTORC1) pathway, a key regulator of autophagy. Inhibition of mTOR1 rescues the impaired osteogenesis by activating autophagy. Collectively, our study highlights the functional importance of COPI in mineralization and identifies COPI as a potential therapeutic target for treating bone-related diseases.
Collapse
Affiliation(s)
| | | | | | | | | | | | - Dandan Pei
- Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi’an Jiaotong University, Xi’an 710004, China
| |
Collapse
|
18
|
Mann D, Fromm SA, Martinez-Sanchez A, Gopaldass N, Choy R, Mayer A, Sachse C. Atg18 oligomer organization in assembled tubes and on lipid membrane scaffolds. Nat Commun 2023; 14:8086. [PMID: 38057304 DOI: 10.1038/s41467-023-43460-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Accepted: 11/09/2023] [Indexed: 12/08/2023] Open
Abstract
Autophagy-related protein 18 (Atg18) participates in the elongation of early autophagosomal structures in concert with Atg2 and Atg9 complexes. How Atg18 contributes to the structural coordination of Atg2 and Atg9 at the isolation membrane remains to be understood. Here, we determined the cryo-EM structures of Atg18 organized in helical tubes, Atg18 oligomers in solution as well as on lipid membrane scaffolds. The helical assembly is composed of Atg18 tetramers forming a lozenge cylindrical lattice with remarkable structural similarity to the COPII outer coat. When reconstituted with lipid membranes, using subtomogram averaging we determined tilted Atg18 dimer structures bridging two juxtaposed lipid membranes spaced apart by 80 Å. Moreover, lipid reconstitution experiments further delineate the contributions of Atg18's FRRG motif and the amphipathic helical extension in membrane interaction. The observed structural plasticity of Atg18's oligomeric organization and membrane binding properties provide a molecular framework for the positioning of downstream components of the autophagy machinery.
Collapse
Affiliation(s)
- Daniel Mann
- Ernst-Ruska Centre 3/Structural Biology, Forschungszentrum Jülich, Wilhelm-Johnen-Straße, Jülich, Germany
- Institute for Biological Information Processing 6/Structural Cellular Biology, Forschungszentrum Jülich, Wilhelm-Johnen-Straße, Jülich, Germany
| | - Simon A Fromm
- Structural and Computational Biology Unit, European Molecular Biology Laboratory (EMBL), Heidelberg, Germany
- EMBL Imaging Centre, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Antonio Martinez-Sanchez
- Department of Information and Communications Engineering, Faculty of Computers Sciences, University of Murcia, Murcia, Spain
| | - Navin Gopaldass
- Department of Biochemistry, University of Lausanne, Epalinges, Switzerland
| | - Ramona Choy
- Ernst-Ruska Centre 3/Structural Biology, Forschungszentrum Jülich, Wilhelm-Johnen-Straße, Jülich, Germany
- Institute for Biological Information Processing 6/Structural Cellular Biology, Forschungszentrum Jülich, Wilhelm-Johnen-Straße, Jülich, Germany
| | - Andreas Mayer
- Department of Biochemistry, University of Lausanne, Epalinges, Switzerland
| | - Carsten Sachse
- Ernst-Ruska Centre 3/Structural Biology, Forschungszentrum Jülich, Wilhelm-Johnen-Straße, Jülich, Germany.
- Institute for Biological Information Processing 6/Structural Cellular Biology, Forschungszentrum Jülich, Wilhelm-Johnen-Straße, Jülich, Germany.
- Department of Biology, Heinrich Heine University, Universitätsstr. 1, Düsseldorf, Germany.
| |
Collapse
|
19
|
Zou CX, Ma ZH, Jiang ZD, Pan ZQ, Xu DD, Suo F, Shao GC, Dong MQ, Du LL. The ortholog of human REEP1-4 is required for autophagosomal enclosure of ER-phagy/nucleophagy cargos in fission yeast. PLoS Biol 2023; 21:e3002372. [PMID: 37939137 PMCID: PMC10659188 DOI: 10.1371/journal.pbio.3002372] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2023] [Revised: 11/20/2023] [Accepted: 10/10/2023] [Indexed: 11/10/2023] Open
Abstract
Selective macroautophagy of the endoplasmic reticulum (ER) and the nucleus, known as ER-phagy and nucleophagy, respectively, are processes whose mechanisms remain inadequately understood. Through an imaging-based screen, we find that in the fission yeast Schizosaccharomyces pombe, Yep1 (also known as Hva22 or Rop1), the ortholog of human REEP1-4, is essential for ER-phagy and nucleophagy but not for bulk autophagy. In the absence of Yep1, the initial phase of ER-phagy and nucleophagy proceeds normally, with the ER-phagy/nucleophagy receptor Epr1 coassembling with Atg8. However, ER-phagy/nucleophagy cargos fail to reach the vacuole. Instead, nucleus- and cortical-ER-derived membrane structures not enclosed within autophagosomes accumulate in the cytoplasm. Intriguingly, the outer membranes of nucleus-derived structures remain continuous with the nuclear envelope-ER network, suggesting a possible outer membrane fission defect during cargo separation from source compartments. We find that the ER-phagy role of Yep1 relies on its abilities to self-interact and shape membranes and requires its C-terminal amphipathic helices. Moreover, we show that human REEP1-4 and budding yeast Atg40 can functionally substitute for Yep1 in ER-phagy, and Atg40 is a divergent ortholog of Yep1 and REEP1-4. Our findings uncover an unexpected mechanism governing the autophagosomal enclosure of ER-phagy/nucleophagy cargos and shed new light on the functions and evolution of REEP family proteins.
Collapse
Affiliation(s)
- Chen-Xi Zou
- National Institute of Biological Sciences, Beijing, China
- College of Life Sciences, Beijing Normal University, Beijing, China
| | - Zhu-Hui Ma
- National Institute of Biological Sciences, Beijing, China
| | - Zhao-Di Jiang
- National Institute of Biological Sciences, Beijing, China
| | - Zhao-Qian Pan
- National Institute of Biological Sciences, Beijing, China
| | - Dan-Dan Xu
- National Institute of Biological Sciences, Beijing, China
| | - Fang Suo
- National Institute of Biological Sciences, Beijing, China
| | - Guang-Can Shao
- National Institute of Biological Sciences, Beijing, China
| | - Meng-Qiu Dong
- National Institute of Biological Sciences, Beijing, China
- Tsinghua Institute of Multidisciplinary Biomedical Research, Tsinghua University, Beijing, China
| | - Li-Lin Du
- National Institute of Biological Sciences, Beijing, China
- Tsinghua Institute of Multidisciplinary Biomedical Research, Tsinghua University, Beijing, China
| |
Collapse
|
20
|
Li G, Li Y, He C, Wei Y, Cai K, Lu Q, Liu X, Zhu Y, Xu K. The promoting effects of pyriproxyfen on autophagy and apoptosis in silk glands of non-target insect silkworm, Bombyx mori. PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY 2023; 196:105586. [PMID: 37945223 DOI: 10.1016/j.pestbp.2023.105586] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 08/12/2023] [Accepted: 08/23/2023] [Indexed: 11/12/2023]
Abstract
Pyriproxyfen is a juvenile hormone analogue. The physiological effects of its low-concentration drift during the process of controlling agricultural and forestry pests on non-target organisms in the ecological environment are unpredictable, especially the effects on organs that play a key role in biological function are worthy of attention. The silk gland is an important organ for silk-secreting insects. Herein, we studied the effects of trace pyriproxyfen on autophagy and apoptosis of the silk gland in the lepidopteran model insect, Bombyx mori (silkworm). After treating fifth instar silkworm larvae with pyriproxyfen for 24 h, we found significant shrinkage, vacuolization, and fragmentation in the posterior silk gland (PSG). In addition, the results of autophagy-related genes of ATG8 and TUNEL assay also demonstrated that autophagy and apoptosis in the PSG of the silkworm was induced by pyriproxyfen. RNA-Seq results showed that pyriproxyfen treatment resulted in the activation of juvenile hormone signaling pathway genes and inhibition of 20-hydroxyecdysone (20E) signaling pathway genes. Among the 1808 significantly differentially expressed genes, 796 were upregulated and 1012 were downregulated. Among them, 30 genes were identified for autophagy-related signaling pathways, such as NOD-like receptor signaling pathway and mTOR signaling pathway, and 30 genes were identified for apoptosis-related signaling pathways, such as P53 signaling pathway and TNF signaling pathway. Further qRT-PCR and in vitro gland culture studies showed that the autophagy-related genes Atg5, Atg6, Atg12, Atg16 and the apoptosis-related genes Aif, Dronc, Dredd, and Caspase1 were responsive to the treatment of pyriproxyfen, with transcription levels up-regulated from 24 to 72 h. In addition, ATG5, ATG6, and Dronc genes had a more direct response to pyriproxyfen treatment. These results suggested that pyriproxyfen treatment could disrupt the hormone regulation in silkworms, promoting autophagy and apoptosis in the PSG. This study provides more evidence for the research on the damage of juvenile hormone analogues to non-target organisms or organs in the environment, and provides reference information for the scientific and rational use of juvenile hormone pesticides.
Collapse
Affiliation(s)
- Guoli Li
- College of Agriculture, Guangxi University, Nanning, Guangxi 530004, PR China
| | - Yizhe Li
- College of Agriculture, Guangxi University, Nanning, Guangxi 530004, PR China
| | - Chunhui He
- College of Agriculture, Guangxi University, Nanning, Guangxi 530004, PR China
| | - Yuting Wei
- College of Agriculture, Guangxi University, Nanning, Guangxi 530004, PR China
| | - Kunpei Cai
- College of Agriculture, Guangxi University, Nanning, Guangxi 530004, PR China
| | - Qingyu Lu
- College of Animal Sciences, Zhejiang University, Hangzhou 310058, PR China
| | - Xuebin Liu
- College of Agriculture, Guangxi University, Nanning, Guangxi 530004, PR China
| | - Yizhou Zhu
- College of Agriculture, Guangxi University, Nanning, Guangxi 530004, PR China
| | - Kaizun Xu
- College of Agriculture, Guangxi University, Nanning, Guangxi 530004, PR China; Guangxi Key Laboratory for Agro-Environment and Agric-Product Safety, National Demonstration Center for Experimental Plant Science Education, College of Agriculture, Guangxi University, Nanning, Guangxi 530004, PR China; Sericulture Institute of Guangxi University, Nanning, Guangxi 530004, PR China.
| |
Collapse
|
21
|
Wang N, Shibata Y, Paulo JA, Gygi SP, Rapoport TA. A conserved membrane curvature-generating protein is crucial for autophagosome formation in fission yeast. Nat Commun 2023; 14:4765. [PMID: 37553386 PMCID: PMC10409813 DOI: 10.1038/s41467-023-40530-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Accepted: 07/26/2023] [Indexed: 08/10/2023] Open
Abstract
Organelles are shaped by curvature-generating proteins, which include the reticulons and REEPs that are involved in forming the endoplasmic reticulum (ER). A conserved REEP subfamily differs from the ER-shaping REEPs in abundance and membrane topology and has unidentified functions. Here, we show that Rop1, the single member of this family in the fission yeast Schizosacharomyces pombe, is crucial for the macroautophagy of organelles and cytosolic proteins. Rop1 is needed for the formation of phagophores, cup-like structures consisting of two closely apposed membrane sheets that encapsulate cargo. It is recruited at early stages to phagophores and is required for their maturation into autophagosomes. Rop1 function relies on its ability to generate high membrane curvature and on its colocalization with the autophagy component Atg2 that is thought to reside at the phagophore rim. We propose that Rop1 facilitates the formation and growth of the double-membrane structure of the autophagosome.
Collapse
Affiliation(s)
- Ning Wang
- Howard Hughes Medical Institute and Department of Cell Biology, Harvard Medical School, 240 Longwood Avenue, Boston, MA, 02115, USA
| | - Yoko Shibata
- Howard Hughes Medical Institute and Department of Cell Biology, Harvard Medical School, 240 Longwood Avenue, Boston, MA, 02115, USA
| | - Joao A Paulo
- Department of Cell Biology, Harvard Medical School, 240 Longwood Avenue, Boston, MA, 02115, USA
| | - Steven P Gygi
- Department of Cell Biology, Harvard Medical School, 240 Longwood Avenue, Boston, MA, 02115, USA
| | - Tom A Rapoport
- Howard Hughes Medical Institute and Department of Cell Biology, Harvard Medical School, 240 Longwood Avenue, Boston, MA, 02115, USA.
| |
Collapse
|
22
|
Dabrowski R, Tulli S, Graef M. Parallel phospholipid transfer by Vps13 and Atg2 determines autophagosome biogenesis dynamics. J Cell Biol 2023; 222:e202211039. [PMID: 37115156 PMCID: PMC10148235 DOI: 10.1083/jcb.202211039] [Citation(s) in RCA: 16] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 03/30/2023] [Accepted: 04/08/2023] [Indexed: 04/29/2023] Open
Abstract
During autophagy, rapid membrane assembly expands small phagophores into large double-membrane autophagosomes. Theoretical modeling predicts that the majority of autophagosomal phospholipids are derived from highly efficient non-vesicular phospholipid transfer (PLT) across phagophore-ER contacts (PERCS). Currently, the phagophore-ER tether Atg2 is the only PLT protein known to drive phagophore expansion in vivo. Here, our quantitative live-cell imaging analysis reveals a poor correlation between the duration and size of forming autophagosomes and the number of Atg2 molecules at PERCS of starving yeast cells. Strikingly, we find that Atg2-mediated PLT is non-rate limiting for autophagosome biogenesis because membrane tether and the PLT protein Vps13 localizes to the rim and promotes the expansion of phagophores in parallel with Atg2. In the absence of Vps13, the number of Atg2 molecules at PERCS determines the duration and size of forming autophagosomes with an apparent in vivo transfer rate of ∼200 phospholipids per Atg2 molecule and second. We propose that conserved PLT proteins cooperate in channeling phospholipids across organelle contact sites for non-rate-limiting membrane assembly during autophagosome biogenesis.
Collapse
Affiliation(s)
- Rahel Dabrowski
- Max Planck Research Group of Autophagy and Cellular Ageing, Max Planck Institute for Biology of Ageing, Cologne, Germany
| | - Susanna Tulli
- Max Planck Research Group of Autophagy and Cellular Ageing, Max Planck Institute for Biology of Ageing, Cologne, Germany
| | - Martin Graef
- Max Planck Research Group of Autophagy and Cellular Ageing, Max Planck Institute for Biology of Ageing, Cologne, Germany
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, USA
| |
Collapse
|
23
|
Avula K, Singh B, Samantaray S, Syed GH. The Early Secretory Pathway Is Crucial for Multiple Aspects of the Hepatitis C Virus Life Cycle. J Virol 2023:e0018023. [PMID: 37338368 PMCID: PMC10373535 DOI: 10.1128/jvi.00180-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Accepted: 06/02/2023] [Indexed: 06/21/2023] Open
Abstract
Although most of the early events of the hepatitis C virus (HCV) life cycle are well characterized, our understanding of HCV egress is still unclear. Some reports implicate the conventional endoplasmic reticulum (ER)-Golgi route, while some propose noncanonical secretory routes. Initially, the envelopment of HCV nucleocapsid occurs by budding into the ER lumen. Subsequently, the HCV particle exit from the ER is assumed to be mediated by coat protein complex II (COPII) vesicles. COPII vesicle biogenesis also involves the recruitment of cargo to the site of vesicle biogenesis via interaction with COPII inner coat proteins. We investigated the modulation and the specific role of the individual components of the early secretory pathway in HCV egress. We observed that HCV inhibits cellular protein secretion and triggers the reorganization of the ER exit sites and ER-Golgi intermediate compartments (ERGIC). Gene-specific knockdown of the components of this pathway such as SEC16A, TFG, ERGIC-53, and COPII coat proteins demonstrated the functional significance of these components and the distinct role played by these proteins in various aspects of the HCV life cycle. SEC16A is essential for multiple steps in the HCV life cycle, whereas TFG is specifically involved in HCV egress and ERGIC-53 is crucial for HCV entry. Overall, our study establishes that the components of the early secretory pathway are essential for HCV propagation and emphasize the importance of the ER-Golgi secretory route in this process. Surprisingly, these components are also required for the early stages of the HCV life cycle due to their role in overall intracellular trafficking and homeostasis of the cellular endomembrane system. IMPORTANCE The virus life cycle involves entry into the host, replication of the genome, assembly of infectious progeny, and their subsequent release. Different aspects of the HCV life cycle, including entry, genome replication, and assembly, are well characterized; however, our understanding of the HCV release is still not clear and subject to debate due to varied findings. Here, we attempted to address this controversy and enhance our understanding of HCV egress by evaluating the role of the different components of the early secretory pathway in the HCV life cycle. To our surprise, we found that the components of the early secretory pathway are not only essential for HCV release but also contribute to many other earlier events of the HCV life cycle. This study emphasizes the importance of the early secretory pathway for the establishment of productive HCV infection in hepatocytes.
Collapse
Affiliation(s)
- Kiran Avula
- Institute of Life Sciences, Bhubaneswar, Odisha, India
- Regional Centre for Biotechnology, Faridabad, Delhi, India
| | - Bharati Singh
- Institute of Life Sciences, Bhubaneswar, Odisha, India
| | | | | |
Collapse
|
24
|
Oh J, Park C, Kim S, Kim M, Kim CS, Jo W, Park S, Yi GS, Park J. High levels of intracellular endotrophin in adipocytes mediate COPII vesicle supplies to autophagosome to impair autophagic flux and contribute to systemic insulin resistance in obesity. Metabolism 2023:155629. [PMID: 37302692 DOI: 10.1016/j.metabol.2023.155629] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Revised: 05/25/2023] [Accepted: 06/08/2023] [Indexed: 06/13/2023]
Abstract
BACKGROUND AND AIMS Extracellular matrix (ECM) homeostasis plays a crucial role in metabolic plasticity and endocrine function of adipose tissue. High levels of intracellular endotrophin, a cleavage peptide of type VI collagen alpha 3 chain (Col6a3), have been frequently observed in adipocyte in obesity and diabetes. However, how endotrophin intracellularly traffics and influences metabolic homeostasis in adipocyte remains unknown. Therefore, we aimed to investigate the trafficking of endotrophin and its metabolic effects in adipocytes depending on lean or obese condition. METHODS We used doxycycline-inducible adipocyte-specific endotrophin overexpressed mice for a gain-of-function study and CRISPR-Cas9 system-based Col6a3-deficient mice for a loss-of-function study. Various molecular and biochemical techniques were employed to examine the effects of endotrophin on metabolic parameters. RESULTS In adipocytes during obesity, the majority of endosomal endotrophin escapes lysosomal degradation and is released into the cytosol to mediate direct interactions between SEC13, a major component of coat protein complex II (COPII) vesicles, and autophagy-related 7 (ATG7), leading to the increased formation of autophagosomes. Autophagosome accumulation disrupts the balance of autophagic flux, resulting in adipocyte death, inflammation, and insulin resistance. These adverse metabolic effects were ameliorated by either suppressing ATG7 with siRNA ex vivo or neutralizing endotrophin with monoclonal antibodies in vivo. CONCLUSIONS High levels of intracellular endotrophin-mediated autophagic flux impairment in adipocyte contribute to metabolic dysfunction such as apoptosis, inflammation, and insulin resistance in obesity.
Collapse
Affiliation(s)
- Jiyoung Oh
- Department of Biological Sciences, College of Information and Biotechnology, Ulsan National Institute of Science and Technology, Ulsan 44919, Republic of Korea
| | - Chanho Park
- Department of Biological Sciences, College of Information and Biotechnology, Ulsan National Institute of Science and Technology, Ulsan 44919, Republic of Korea
| | - Sahee Kim
- Department of Biological Sciences, College of Information and Biotechnology, Ulsan National Institute of Science and Technology, Ulsan 44919, Republic of Korea
| | - Min Kim
- Department of Biological Sciences, College of Information and Biotechnology, Ulsan National Institute of Science and Technology, Ulsan 44919, Republic of Korea
| | - Chu-Sook Kim
- Department of Biological Sciences, College of Information and Biotechnology, Ulsan National Institute of Science and Technology, Ulsan 44919, Republic of Korea
| | - Woobeen Jo
- Department of Biological Sciences, College of Information and Biotechnology, Ulsan National Institute of Science and Technology, Ulsan 44919, Republic of Korea
| | - Sungho Park
- Department of Biological Sciences, College of Information and Biotechnology, Ulsan National Institute of Science and Technology, Ulsan 44919, Republic of Korea
| | - Gwan-Su Yi
- Department of Bio and Brain Engineering, Korea Advanced Institute of Science and Technology, Daejeon 34141, Republic of Korea
| | - Jiyoung Park
- Department of Biological Sciences, College of Information and Biotechnology, Ulsan National Institute of Science and Technology, Ulsan 44919, Republic of Korea.
| |
Collapse
|
25
|
Tapia D, Cavieres VA, Burgos PV, Cancino J. Impact of interorganelle coordination between the conventional early secretory pathway and autophagy in cellular homeostasis and stress response. Front Cell Dev Biol 2023; 11:1069256. [PMID: 37152281 PMCID: PMC10160633 DOI: 10.3389/fcell.2023.1069256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Accepted: 04/07/2023] [Indexed: 05/09/2023] Open
Abstract
The conventional early secretory pathway and autophagy are two essential interconnected cellular processes that are crucial for maintaining cellular homeostasis. The conventional secretory pathway is an anabolic cellular process synthesizing and delivering proteins to distinct locations, including different organelles, the plasma membrane, and the extracellular media. On the other hand, autophagy is a catabolic cellular process that engulfs damaged organelles and aberrant cytosolic constituents into the double autophagosome membrane. After fusion with the lysosome and autolysosome formation, this process triggers digestion and recycling. A growing list of evidence indicates that these anabolic and catabolic processes are mutually regulated. While knowledge about the molecular actors involved in the coordination and functional cooperation between these two processes has increased over time, the mechanisms are still poorly understood. This review article summarized and discussed the most relevant evidence about the key molecular players implicated in the interorganelle crosstalk between the early secretory pathway and autophagy under normal and stressful conditions.
Collapse
Affiliation(s)
- Diego Tapia
- Cell Biology of Interorganelle Signaling Laboratory, Centro de Biología Celular y Biomedicina (CEBICEM), Facultad de Medicina y Ciencia, Universidad San Sebastián, Santiago, Chile
| | - Viviana A. Cavieres
- Organelle Phagy Lab, Centro de Biología Celular y Biomedicina (CEBICEM), Facultad de Medicina y Ciencia, Universidad San Sebastián, Santiago, Chile
| | - Patricia V. Burgos
- Organelle Phagy Lab, Centro de Biología Celular y Biomedicina (CEBICEM), Facultad de Medicina y Ciencia, Universidad San Sebastián, Santiago, Chile
- Centro Ciencia & Vida, Fundación Ciencia & Vida, Santiago, Chile
| | - Jorge Cancino
- Cell Biology of Interorganelle Signaling Laboratory, Centro de Biología Celular y Biomedicina (CEBICEM), Facultad de Medicina y Ciencia, Universidad San Sebastián, Santiago, Chile
| |
Collapse
|
26
|
Liu L, Tang Y, Zhou Z, Huang Y, Zhang R, Lyu H, Xiao S, Guo D, Ali DW, Michalak M, Chen XZ, Zhou C, Tang J. Membrane Curvature: The Inseparable Companion of Autophagy. Cells 2023; 12:1132. [PMID: 37190041 PMCID: PMC10136490 DOI: 10.3390/cells12081132] [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: 12/07/2022] [Revised: 04/06/2023] [Accepted: 04/10/2023] [Indexed: 05/17/2023] Open
Abstract
Autophagy is a highly conserved recycling process of eukaryotic cells that degrades protein aggregates or damaged organelles with the participation of autophagy-related proteins. Membrane bending is a key step in autophagosome membrane formation and nucleation. A variety of autophagy-related proteins (ATGs) are needed to sense and generate membrane curvature, which then complete the membrane remodeling process. The Atg1 complex, Atg2-Atg18 complex, Vps34 complex, Atg12-Atg5 conjugation system, Atg8-phosphatidylethanolamine conjugation system, and transmembrane protein Atg9 promote the production of autophagosomal membranes directly or indirectly through their specific structures to alter membrane curvature. There are three common mechanisms to explain the change in membrane curvature. For example, the BAR domain of Bif-1 senses and tethers Atg9 vesicles to change the membrane curvature of the isolation membrane (IM), and the Atg9 vesicles are reported as a source of the IM in the autophagy process. The amphiphilic helix of Bif-1 inserts directly into the phospholipid bilayer, causing membrane asymmetry, and thus changing the membrane curvature of the IM. Atg2 forms a pathway for lipid transport from the endoplasmic reticulum to the IM, and this pathway also contributes to the formation of the IM. In this review, we introduce the phenomena and causes of membrane curvature changes in the process of macroautophagy, and the mechanisms of ATGs in membrane curvature and autophagosome membrane formation.
Collapse
Affiliation(s)
- Lei Liu
- Cooperative Innovation Center of Industrial Fermentation (Ministry of Education & Hubei Province), Hubei Key Laboratory of Industrial Microbiology, Hubei University of Technology, Wuhan 430068, China
- National “111” Center for Cellular Regulation and Molecular Pharmaceutics, Key Laboratory of Fermentation Engineering (Ministry of Education), Hubei University of Technology, Wuhan 430068, China
| | - Yu Tang
- Cooperative Innovation Center of Industrial Fermentation (Ministry of Education & Hubei Province), Hubei Key Laboratory of Industrial Microbiology, Hubei University of Technology, Wuhan 430068, China
- National “111” Center for Cellular Regulation and Molecular Pharmaceutics, Key Laboratory of Fermentation Engineering (Ministry of Education), Hubei University of Technology, Wuhan 430068, China
| | - Zijuan Zhou
- Cooperative Innovation Center of Industrial Fermentation (Ministry of Education & Hubei Province), Hubei Key Laboratory of Industrial Microbiology, Hubei University of Technology, Wuhan 430068, China
- National “111” Center for Cellular Regulation and Molecular Pharmaceutics, Key Laboratory of Fermentation Engineering (Ministry of Education), Hubei University of Technology, Wuhan 430068, China
| | - Yuan Huang
- Cooperative Innovation Center of Industrial Fermentation (Ministry of Education & Hubei Province), Hubei Key Laboratory of Industrial Microbiology, Hubei University of Technology, Wuhan 430068, China
| | - Rui Zhang
- Cooperative Innovation Center of Industrial Fermentation (Ministry of Education & Hubei Province), Hubei Key Laboratory of Industrial Microbiology, Hubei University of Technology, Wuhan 430068, China
| | - Hao Lyu
- Cooperative Innovation Center of Industrial Fermentation (Ministry of Education & Hubei Province), Hubei Key Laboratory of Industrial Microbiology, Hubei University of Technology, Wuhan 430068, China
| | - Shuai Xiao
- Cooperative Innovation Center of Industrial Fermentation (Ministry of Education & Hubei Province), Hubei Key Laboratory of Industrial Microbiology, Hubei University of Technology, Wuhan 430068, China
| | - Dong Guo
- Cooperative Innovation Center of Industrial Fermentation (Ministry of Education & Hubei Province), Hubei Key Laboratory of Industrial Microbiology, Hubei University of Technology, Wuhan 430068, China
| | - Declan William Ali
- Department of Biological Sciences, University of Alberta, Edmonton, AB T6G 2R3, Canada
| | - Marek Michalak
- Department of Biochemistry, University of Alberta, Edmonton, AB T6G 2R3, Canada
| | - Xing-Zhen Chen
- Membrane Protein Disease Research Group, Department of Physiology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB T6G 2R3, Canada
| | - Cefan Zhou
- Cooperative Innovation Center of Industrial Fermentation (Ministry of Education & Hubei Province), Hubei Key Laboratory of Industrial Microbiology, Hubei University of Technology, Wuhan 430068, China
| | - Jingfeng Tang
- Cooperative Innovation Center of Industrial Fermentation (Ministry of Education & Hubei Province), Hubei Key Laboratory of Industrial Microbiology, Hubei University of Technology, Wuhan 430068, China
| |
Collapse
|
27
|
Qian H, Sun L, Wu M, Zhao W, Liu M, Liang S, Zhu X, Li L, Su Z, Lu J, Lin F, Liu X. The COPII subunit MoSec24B is involved in development, pathogenicity and autophagy in the rice blast fungus. FRONTIERS IN PLANT SCIENCE 2023; 13:1074107. [PMID: 36699840 PMCID: PMC9868959 DOI: 10.3389/fpls.2022.1074107] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Accepted: 12/08/2022] [Indexed: 06/17/2023]
Abstract
The endoplasmic reticulum (ER) acts as the starting point of the secretory pathway, where approximately one-third of the proteins are correctly folded and modified, loaded into vesicles, and transported to the Golgi for further processing and modification. In this process, COPII vesicles are responsible for transporting cargo proteins from the ER to the Golgi. Here, we identified the inner shell subunit of COPII vesicles (MoSec24B) and explored the importance of MoSec24B in the rice blast fungus. The targeted disruption of MoSec24B led to decreased growth, reduced conidiation, restricted glycogen and lipids utilization, sensitivity to the cell wall and hypertonic stress, the failure of septin-mediated repolarization of appressorium, impaired appressorium turgor pressure, and decreased ability to infect, which resulted in reduced pathogenicity to the host plant. Furthermore, MoSec24B functions in the three mitogen-activated protein kinase (MAPK) signaling pathways by acting with MoMst50. Deletion of MoSec24B caused reduced lipidation of MoAtg8, accelerated degradation of exogenously introduced GFP-MoAtg8, and increased lipidation of MoAtg8 upon treatment with a late inhibitor of autophagy (BafA1), suggesting that MoSec24B regulates the fusion of late autophagosomes with vacuoles. Together, these results suggest that MoSec24B exerts a significant role in fungal development, the pathogenesis of filamentous fungi and autophagy.
Collapse
Affiliation(s)
- Hui Qian
- State Key Laboratory for Managing Biotic and Chemical Treats to the Quality and Safety of Agro-products, Institute of Biotechnology, Zhejiang University, Hangzhou, China
| | - Lixiao Sun
- State Key Laboratory for Managing Biotic and Chemical Treats to the Quality and Safety of Agro-products, Institute of Biotechnology, Zhejiang University, Hangzhou, China
| | - Minghua Wu
- State Key Laboratory for Managing Biotic and Chemical Treats to the Quality and Safety of Agro-products, Institute of Biotechnology, Zhejiang University, Hangzhou, China
| | - Wenhui Zhao
- State Key Laboratory for Managing Biotic and Chemical Treats to the Quality and Safety of Agro-products, Institute of Biotechnology, Zhejiang University, Hangzhou, China
| | - Mengyu Liu
- State Key Laboratory for Managing Biotic and Chemical Treats to the Quality and Safety of Agro-products, Institute of Biotechnology, Zhejiang University, Hangzhou, China
| | - Shuang Liang
- State Key Laboratory for Managing Biotic and Chemical Treats to the Quality and Safety of Agro-products, Institute of Plant Protection and Microbiology, Zhejiang Academy of Agricultural Sciences, Hangzhou, China
| | - Xueming Zhu
- State Key Laboratory for Managing Biotic and Chemical Treats to the Quality and Safety of Agro-products, Institute of Plant Protection and Microbiology, Zhejiang Academy of Agricultural Sciences, Hangzhou, China
| | - Lin Li
- State Key Laboratory for Managing Biotic and Chemical Treats to the Quality and Safety of Agro-products, Institute of Plant Protection and Microbiology, Zhejiang Academy of Agricultural Sciences, Hangzhou, China
| | - Zhenzhu Su
- State Key Laboratory for Managing Biotic and Chemical Treats to the Quality and Safety of Agro-products, Institute of Biotechnology, Zhejiang University, Hangzhou, China
| | - Jianping Lu
- College of Life Sciences, Zhejiang University, Hangzhou, China
| | - Fucheng Lin
- State Key Laboratory for Managing Biotic and Chemical Treats to the Quality and Safety of Agro-products, Institute of Biotechnology, Zhejiang University, Hangzhou, China
- State Key Laboratory for Managing Biotic and Chemical Treats to the Quality and Safety of Agro-products, Institute of Plant Protection and Microbiology, Zhejiang Academy of Agricultural Sciences, Hangzhou, China
| | - Xiaohong Liu
- State Key Laboratory for Managing Biotic and Chemical Treats to the Quality and Safety of Agro-products, Institute of Biotechnology, Zhejiang University, Hangzhou, China
| |
Collapse
|
28
|
Chino H, Mizushima N. ER-Phagy: Quality and Quantity Control of the Endoplasmic Reticulum by Autophagy. Cold Spring Harb Perspect Biol 2023; 15:cshperspect.a041256. [PMID: 35940904 PMCID: PMC9808580 DOI: 10.1101/cshperspect.a041256] [Citation(s) in RCA: 20] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
The endoplasmic reticulum (ER) is the largest organelle and has multiple roles in various cellular processes such as protein secretion, lipid synthesis, calcium storage, and organelle biogenesis. The quantity and quality of this organelle are controlled by the ubiquitin-proteasome system and autophagy (termed "ER-phagy"). ER-phagy is defined as the degradation of part of the ER by the vacuole or lysosomes, and there are at least two types of ER-phagy: macro-ER-phagy and micro-ER-phagy. In macro-ER-phagy, ER fragments are enclosed by autophagosomes, which is mediated by ER-phagy receptors. In micro-ER-phagy, a portion of the ER is engulfed directly by the vacuole or lysosomes. In these two pathways, some proteins in the ER lumen can be recognized selectively and subjected to ER-phagy. This review summarizes our current knowledge of ER-phagy, focusing on its membrane dynamics, molecular mechanisms, substrate specificity, and physiological significance.
Collapse
Affiliation(s)
- Haruka Chino
- Department of Biochemistry and Molecular Biology, Graduate School of Medicine, The University of Tokyo, Tokyo 113-0033, Japan
| | - Noboru Mizushima
- Department of Biochemistry and Molecular Biology, Graduate School of Medicine, The University of Tokyo, Tokyo 113-0033, Japan
| |
Collapse
|
29
|
Capitanio C, Bieber A, Wilfling F. How Membrane Contact Sites Shape the Phagophore. CONTACT (THOUSAND OAKS (VENTURA COUNTY, CALIF.)) 2023; 6:25152564231162495. [PMID: 37366413 PMCID: PMC10243513 DOI: 10.1177/25152564231162495] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 02/15/2023] [Accepted: 02/18/2023] [Indexed: 06/28/2023]
Abstract
During macroautophagy, phagophores establish multiple membrane contact sites (MCSs) with other organelles that are pivotal for proper phagophore assembly and growth. In S. cerevisiae, phagophore contacts have been observed with the vacuole, the ER, and lipid droplets. In situ imaging studies have greatly advanced our understanding of the structure and function of these sites. Here, we discuss how in situ structural methods like cryo-CLEM can give unprecedented insights into MCSs, and how they help to elucidate the structural arrangements of MCSs within cells. We further summarize the current knowledge of the contact sites in autophagy, focusing on autophagosome biogenesis in the model organism S. cerevisiae.
Collapse
Affiliation(s)
- Cristina Capitanio
- Department of Molecular Machines and
Signaling, Max Planck Institute of Biochemistry, Martinsried, Germany
- Aligning Science Across Parkinson's (ASAP)
Collaborative Research Network, Chevy Chase, MD, USA
| | - Anna Bieber
- Department of Molecular Machines and
Signaling, Max Planck Institute of Biochemistry, Martinsried, Germany
- Aligning Science Across Parkinson's (ASAP)
Collaborative Research Network, Chevy Chase, MD, USA
| | - Florian Wilfling
- Mechanisms of Cellular Quality Control, Max Planck Institute of Biophysics, Frankfurt a. M., Germany
| |
Collapse
|
30
|
Fan G, Li F, Wang P, Jin X, Liu R. Natural-Product-Mediated Autophagy in the Treatment of Various Liver Diseases. Int J Mol Sci 2022; 23:ijms232315109. [PMID: 36499429 PMCID: PMC9739742 DOI: 10.3390/ijms232315109] [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: 11/01/2022] [Revised: 11/11/2022] [Accepted: 11/15/2022] [Indexed: 12/05/2022] Open
Abstract
Autophagy is essential for the maintenance of hepatic homeostasis, and autophagic malfunction has been linked to the pathogenesis of substantial liver diseases. As a popular source of drug discovery, natural products have been used for centuries to effectively prevent the progression of various liver diseases. Emerging evidence has suggested that autophagy regulation is a critical mechanism underlying the therapeutic effects of these natural products. In this review, relevant studies are retrieved from scientific databases published between 2011 and 2022, and a novel scoring system was established to critically evaluate the completeness and scientific significance of the reviewed literature. We observed that numerous natural products were suggested to regulate autophagic flux. Depending on the therapeutic or pathogenic role autophagy plays in different liver diseases, autophagy-regulative natural products exhibit different therapeutic effects. According to our novel scoring system, in a considerable amount of the involved studies, convincing and reasonable evidence to elucidate the regulatory effects and underlying mechanisms of natural-product-mediated autophagy regulation was missing and needed further illustration. We highlight that autophagy-regulative natural products are valuable drug candidates with promising prospects for the treatment of liver diseases and deserve more attention in the future.
Collapse
Affiliation(s)
- Guifang Fan
- School of Chinese Materia Medica, Beijing University of Chinese Medicine, 11 Bei San Huan Dong Lu, Beijing 100029, China
| | - Fanghong Li
- School of Chinese Materia Medica, Beijing University of Chinese Medicine, 11 Bei San Huan Dong Lu, Beijing 100029, China
| | - Ping Wang
- Center for Evidence-Based Chinese Medicine, Beijing University of Chinese Medicine, 11 Bei San Huan Dong Lu, Beijing 100029, China
| | - Xuejing Jin
- Center for Evidence-Based Chinese Medicine, Beijing University of Chinese Medicine, 11 Bei San Huan Dong Lu, Beijing 100029, China
- Correspondence: (X.J.); (R.L.); Tel.: +86-15632374331 (X.J.); +86-10-53912122 (R.L.)
| | - Runping Liu
- School of Chinese Materia Medica, Beijing University of Chinese Medicine, 11 Bei San Huan Dong Lu, Beijing 100029, China
- Correspondence: (X.J.); (R.L.); Tel.: +86-15632374331 (X.J.); +86-10-53912122 (R.L.)
| |
Collapse
|
31
|
Chumpen Ramirez S, Gómez-Sánchez R, Verlhac P, Hardenberg R, Margheritis E, Cosentino K, Reggiori F, Ungermann C. --Atg9 interactions via its transmembrane domains are required for phagophore expansion during autophagy. Autophagy 2022:1-20. [PMID: 36354155 DOI: 10.1080/15548627.2022.2136340] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
During macroautophagy/autophagy, precursor cisterna known as phagophores expand and sequester portions of the cytoplasm and/or organelles, and subsequently close resulting in double-membrane transport vesicles called autophagosomes. Autophagosomes fuse with lysosomes/vacuoles to allow the degradation and recycling of their cargoes. We previously showed that sequential binding of yeast Atg2 and Atg18 to Atg9, the only conserved transmembrane protein in autophagy, at the extremities of the phagophore mediates the establishment of membrane contact sites between the phagophore and the endoplasmic reticulum. As the Atg2-Atg18 complex transfers lipids between adjacent membranes in vitro, it has been postulated that this activity and the scramblase activity of the trimers formed by Atg9 are required for the phagophore expansion. Here, we present evidence that Atg9 indeed promotes Atg2-Atg18 complex-mediated lipid transfer in vitro, although this is not the only requirement for its function in vivo. In particular, we show that Atg9 function is dramatically compromised by a F627A mutation within the conserved interface between the transmembrane domains of the Atg9 monomers. Although Atg9F627A self-interacts and binds to the Atg2-Atg18 complex, the F627A mutation blocks the phagophore expansion and thus autophagy progression. This phenotype is conserved because the corresponding human ATG9A mutant severely impairs autophagy as well. Importantly, Atg9F627A has identical scramblase activity in vitro like Atg9, and as with the wild-type protein enhances Atg2-Atg18-mediated lipid transfer. Collectively, our data reveal that interactions of Atg9 trimers via their transmembrane segments play a key role in phagophore expansion beyond Atg9's role as a lipid scramblase.Abbreviations: BafA1: bafilomycin A1; Cvt: cytoplasm-to-vacuole targeting; Cryo-EM: cryo-electron microscopy; ER: endoplasmic reticulum; GFP: green fluorescent protein; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; MCS: membrane contact site; NBD-PE: N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)-1,2-dihexadecanoyl-sn-glycero-3-phosphoethanolamine; PAS: phagophore assembly site; PE: phosphatidylethanolamine; prApe1: precursor Ape1; PtdIns3P: phosphatidylinositol-3-phosphate; SLB: supported lipid bilayer; SUV: small unilamellar vesicle; TMD: transmembrane domain; WT: wild type.
Collapse
Affiliation(s)
- Sabrina Chumpen Ramirez
- Osnabrück University, Department of Biology/Chemistry, Biochemistry section, Osnabrück, Germany
| | - Rubén Gómez-Sánchez
- Department of Biomedical Sciences of Cells and Systems, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Pauline Verlhac
- Department of Biomedical Sciences of Cells and Systems, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Ralph Hardenberg
- Department of Biomedical Sciences of Cells and Systems, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | | | - Katia Cosentino
- Osnabrück University, Department of Biology/Chemistry, Osnabrück, Germany.,Center of Cellular Nanoanalytic Osnabrück (CellNanOs), Osnabrück University, Osnabrück, Germany
| | - Fulvio Reggiori
- Department of Biomedical Sciences of Cells and Systems, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.,Department of Biomedicine, Aarhus University, Ole Worms Alle 4, 8000 Aarhus C, Aarhus, Denmark.,Aarhus Institute of Advanced Studies (AIAS), Aarhus University, Aarhus C, Denmark
| | - Christian Ungermann
- Osnabrück University, Department of Biology/Chemistry, Biochemistry section, Osnabrück, Germany.,Center of Cellular Nanoanalytic Osnabrück (CellNanOs), Osnabrück University, Osnabrück, Germany
| |
Collapse
|
32
|
Gudmundsson SR, Kallio KA, Vihinen H, Jokitalo E, Ktistakis N, Eskelinen EL. Morphology of Phagophore Precursors by Correlative Light-Electron Microscopy. Cells 2022; 11:cells11193080. [PMID: 36231043 PMCID: PMC9562894 DOI: 10.3390/cells11193080] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Revised: 09/20/2022] [Accepted: 09/23/2022] [Indexed: 11/16/2022] Open
Abstract
Autophagosome biogenesis occurs in the transient subdomains of the endoplasmic reticulum that are called omegasomes, which, in fluorescence microscopy, appear as small puncta, which then grow in diameter and finally shrink and disappear once the autophagosome is complete. Autophagosomes are formed by phagophores, which are membrane cisterns that elongate and close to form the double membrane that limits autophagosomes. Earlier electron-microscopy studies showed that, during elongation, phagophores are lined by the endoplasmic reticulum on both sides. However, the morphology of the very early phagophore precursors has not been studied at the electron-microscopy level. We used live-cell imaging of cells expressing markers of phagophore biogenesis combined with correlative light-electron microscopy, as well as electron tomography of ATG2A/B-double-deficient cells, to reveal the high-resolution morphology of phagophore precursors in three dimensions. We showed that phagophores are closed or nearly closed into autophagosomes already at the stage when the omegasome diameter is still large. We further observed that phagophore precursors emerge next to the endoplasmic reticulum as bud-like highly curved membrane cisterns with a small opening to the cytosol. The phagophore precursors then open to form more flat cisterns that elongate and curve to form the classically described crescent-shaped phagophores.
Collapse
Affiliation(s)
- Sigurdur Runar Gudmundsson
- Molecular and Integrative Biosciences, University of Helsinki, 00790 Helsinki, Finland
- Biomedical Center, School of Health Sciences, University of Iceland, 101 Reykjavik, Iceland
| | - Katri A. Kallio
- Molecular and Integrative Biosciences, University of Helsinki, 00790 Helsinki, Finland
| | - Helena Vihinen
- Institute of Biotechnology, University of Helsinki, 00790 Helsinki, Finland
| | - Eija Jokitalo
- Institute of Biotechnology, University of Helsinki, 00790 Helsinki, Finland
| | | | - Eeva-Liisa Eskelinen
- Institute of Biomedicine, University of Turku, 20520 Turku, Finland
- Correspondence: ; Tel.: +358-505115631
| |
Collapse
|
33
|
Bieber A, Capitanio C, Erdmann PS, Fiedler F, Beck F, Lee CW, Li D, Hummer G, Schulman BA, Baumeister W, Wilfling F. In situ structural analysis reveals membrane shape transitions during autophagosome formation. Proc Natl Acad Sci U S A 2022; 119:e2209823119. [PMID: 36122245 PMCID: PMC9522377 DOI: 10.1073/pnas.2209823119] [Citation(s) in RCA: 52] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Accepted: 08/09/2022] [Indexed: 11/18/2022] Open
Abstract
Autophagosomes are unique organelles that form de novo as double-membrane vesicles engulfing cytosolic material for destruction. Their biogenesis involves membrane transformations of distinctly shaped intermediates whose ultrastructure is poorly understood. Here, we combine cell biology, correlative cryo-electron tomography (cryo-ET), and extensive data analysis to reveal the step-by-step structural progression of autophagosome biogenesis at high resolution directly within yeast cells. The analysis uncovers an unexpectedly thin intermembrane distance that is dilated at the phagophore rim. Mapping of individual autophagic structures onto a timeline based on geometric features reveals a dynamical change of membrane shape and curvature in growing phagophores. Moreover, our tomograms show the organelle interactome of growing autophagosomes, highlighting a polar organization of contact sites between the phagophore and organelles, such as the vacuole and the endoplasmic reticulum (ER). Collectively, these findings have important implications for the contribution of different membrane sources during autophagy and for the forces shaping and driving phagophores toward closure without a templating cargo.
Collapse
Affiliation(s)
- Anna Bieber
- Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany
- Department of Molecular Machines and Signaling, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany
- Aligning Science Across Parkinson’s (ASAP) Collaborative Research Network, Chevy Chase, MD 20815
| | - Cristina Capitanio
- Department of Molecular Machines and Signaling, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany
- Aligning Science Across Parkinson’s (ASAP) Collaborative Research Network, Chevy Chase, MD 20815
| | - Philipp S. Erdmann
- Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany
- Human Technopole, 20157 Milan, Italy
| | - Fabian Fiedler
- Mechanisms of Cellular Quality Control, Max Planck Institute of Biophysics, 60438 Frankfurt a. M., Germany
| | - Florian Beck
- Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany
- CryoEM Technology, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany
| | - Chia-Wei Lee
- Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany
- Department of Molecular Metabolism, Harvard T. H. Chan School of Public Health, Boston, MA 02115
| | - Delong Li
- Mechanisms of Cellular Quality Control, Max Planck Institute of Biophysics, 60438 Frankfurt a. M., Germany
| | - Gerhard Hummer
- Aligning Science Across Parkinson’s (ASAP) Collaborative Research Network, Chevy Chase, MD 20815
- Department of Theoretical Biophysics, Max Planck Institute of Biophysics, 60438 Frankfurt a. M., Germany
- Institute of Biophysics, Goethe University Frankfurt, 60438 Frankfurt a. M., Germany
| | - Brenda A. Schulman
- Department of Molecular Machines and Signaling, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany
- Aligning Science Across Parkinson’s (ASAP) Collaborative Research Network, Chevy Chase, MD 20815
| | - Wolfgang Baumeister
- Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany
- Aligning Science Across Parkinson’s (ASAP) Collaborative Research Network, Chevy Chase, MD 20815
| | - Florian Wilfling
- Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany
- Department of Molecular Machines and Signaling, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany
- Aligning Science Across Parkinson’s (ASAP) Collaborative Research Network, Chevy Chase, MD 20815
- Mechanisms of Cellular Quality Control, Max Planck Institute of Biophysics, 60438 Frankfurt a. M., Germany
| |
Collapse
|
34
|
Navarro-Betancourt JR, Cybulsky AV. The IRE1α pathway in glomerular diseases: The unfolded protein response and beyond. FRONTIERS IN MOLECULAR MEDICINE 2022; 2:971247. [PMID: 39086958 PMCID: PMC11285563 DOI: 10.3389/fmmed.2022.971247] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Accepted: 09/07/2022] [Indexed: 08/02/2024]
Abstract
Endoplasmic reticulum (ER) function is vital for protein homeostasis ("proteostasis"). Protein misfolding in the ER of podocytes (glomerular visceral epithelial cells) is an important contributor to the pathogenesis of human glomerular diseases. ER protein misfolding causes ER stress and activates a compensatory signaling network called the unfolded protein response (UPR). Disruption of the UPR, in particular deletion of the UPR transducer, inositol-requiring enzyme 1α (IRE1α) in mouse podocytes leads to podocyte injury and albuminuria in aging, and exacerbates injury in glomerulonephritis. The UPR may interact in a coordinated manner with autophagy to relieve protein misfolding and its consequences. Recent studies have identified novel downstream targets of IRE1α, which provide new mechanistic insights into proteostatic pathways. Novel pathways of IRE1α signaling involve reticulophagy, mitochondria, metabolism, vesicular trafficking, microRNAs, and others. Mechanism-based therapies for glomerulopathies are limited, and development of non-invasive ER stress biomarkers, as well as targeting ER stress with pharmacological compounds may represent a therapeutic opportunity for preventing or attenuating progression of chronic kidney disease.
Collapse
Affiliation(s)
| | - Andrey V. Cybulsky
- Department of Medicine, McGill University Health Centre Research Institute, McGill University, Montreal, QC, Canada
| |
Collapse
|
35
|
Mochida K, Nakatogawa H. ER
‐phagy: selective autophagy of the endoplasmic reticulum. EMBO Rep 2022; 23:e55192. [PMID: 35758175 PMCID: PMC9346472 DOI: 10.15252/embr.202255192] [Citation(s) in RCA: 43] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Revised: 05/24/2022] [Accepted: 06/08/2022] [Indexed: 12/22/2022] Open
Abstract
Eukaryotic cells adequately control the mass and functions of organelles in various situations. Autophagy, an intracellular degradation system, largely contributes to this organelle control by degrading the excess or defective portions of organelles. The endoplasmic reticulum (ER) is an organelle with distinct structural domains associated with specific functions. The ER dynamically changes its mass, components, and shape in response to metabolic, developmental, or proteotoxic cues to maintain or regulate its functions. Therefore, elaborate mechanisms are required for proper degradation of the ER. Here, we review our current knowledge on diverse mechanisms underlying selective autophagy of the ER, which enable efficient degradation of specific ER subdomains according to different demands of cells.
Collapse
Affiliation(s)
- Keisuke Mochida
- School of Life Science and Technology Tokyo Institute of Technology Yokohama Japan
| | - Hitoshi Nakatogawa
- School of Life Science and Technology Tokyo Institute of Technology Yokohama Japan
| |
Collapse
|
36
|
Majeed ST, Majeed R, Andrabi KI. Expanding the view of the molecular mechanisms of autophagy pathway. J Cell Physiol 2022; 237:3257-3277. [DOI: 10.1002/jcp.30819] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Revised: 06/01/2022] [Accepted: 06/07/2022] [Indexed: 01/18/2023]
Affiliation(s)
- Sheikh Tahir Majeed
- Department of Biotechnology Central University of Kashmir Ganderbal Jammu and Kashmir India
- Growth Factor Signaling Laboratory, Department of Biotechnology University of Kashmir Srinagar Jammu and Kashmir India
| | - Rabiya Majeed
- Growth Factor Signaling Laboratory, Department of Biotechnology University of Kashmir Srinagar Jammu and Kashmir India
- Department of Biochemistry University of Kashmir Srinagar Jammu and Kashmir India
| | - Khurshid I. Andrabi
- Growth Factor Signaling Laboratory, Department of Biotechnology University of Kashmir Srinagar Jammu and Kashmir India
| |
Collapse
|
37
|
Baines K, Yoshioka K, Takuwa Y, Lane JD. The ATG5 interactome links clathrin-mediated vesicular trafficking with the autophagosome assembly machinery. AUTOPHAGY REPORTS 2022; 1:88-118. [PMID: 35449600 PMCID: PMC9015699 DOI: 10.1080/27694127.2022.2042054] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
Abstract
Autophagosome formation involves the sequential actions of conserved ATG proteins to coordinate the lipidation of the ubiquitin-like modifier Atg8-family proteins at the nascent phagophore membrane. Although the molecular steps driving this process are well understood, the source of membranes for the expanding phagophore and their mode of delivery are only now beginning to be revealed. Here, we have used quantitative SILAC-based proteomics to identify proteins that associate with the ATG12-ATG5 conjugate, a crucial player during Atg8-family protein lipidation. Our datasets reveal a strong enrichment of regulators of clathrin-mediated vesicular trafficking, including clathrin heavy and light chains, and several clathrin adaptors. Also identified were PIK3C2A (a phosphoinositide 3-kinase involved in clathrin-mediated endocytosis) and HIP1R (a component of clathrin vesicles), and the absence of either of these proteins alters autophagic flux in cell-based starvation assays. To determine whether the ATG12-ATG5 conjugate reciprocally influences trafficking within the endocytic compartment, we captured the cell surface proteomes of autophagy-competent and autophagy-incompetent mouse embryonic fibroblasts under fed and starved conditions. We report changes in the relative proportions of individual cell surface proteins and show that cell surface levels of the SLC7A5-SLC3A2 amino acid transporter are influenced by autophagy capability. Our data provide evidence for direct regulatory coupling between the ATG12-ATG5 conjugate and the clathrin membrane trafficking system and suggest candidate membrane proteins whose trafficking within the cell may be modulated by the autophagy machinery. Abbreviations: ATG, autophagy related; BafA1, bafilomycin A1; GFP, green fluorescent protein; HIP1R, huntingtin interacting protein 1 related; MEF, mouse embryo fibroblast; PIK3C2A, phosphatidylinositol-4-phosphate 3-kinase catalytic subunit type 2 alpha; SILAC, stable isotope labelling with amino acids in culture; SQSTM1, sequestosome 1; STRING, search tool for the retrieval of interacting genes/proteins.
Collapse
Affiliation(s)
- Kiren Baines
- Cell Biology Laboratories, School of Biochemistry, University of Bristol, University Walk, Bristol, BS81TD, UK
| | - Kazuaki Yoshioka
- Department of Physiology, Kanazawa University Graduate School of Medical Sciences, 13-1 Takara-machi, Kanazawa Ishikawa920-8640, Japan
| | - Yoh Takuwa
- Department of Physiology, Kanazawa University Graduate School of Medical Sciences, 13-1 Takara-machi, Kanazawa Ishikawa920-8640, Japan
| | - Jon D. Lane
- Cell Biology Laboratories, School of Biochemistry, University of Bristol, University Walk, Bristol, BS81TD, UK
| |
Collapse
|
38
|
Genetic disorders of cellular trafficking. Trends Genet 2022; 38:724-751. [DOI: 10.1016/j.tig.2022.02.012] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2021] [Revised: 02/11/2022] [Accepted: 02/28/2022] [Indexed: 02/06/2023]
|
39
|
TRK-fused gene (TFG) regulates ULK1 stability via TRAF3-mediated ubiquitination and protects macrophages from LPS-induced pyroptosis. Cell Death Dis 2022; 13:93. [PMID: 35091545 PMCID: PMC8795729 DOI: 10.1038/s41419-022-04539-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 12/22/2021] [Accepted: 01/14/2022] [Indexed: 12/12/2022]
Abstract
TRK-fused gene (TFG) is known to be involved in protein secretion and plays essential roles in an antiviral innate immune response. However, its function in LPS-induced inflammation and pyroptotic cell death is still unknown. Here, we reported that TFG promotes the stabilization of Unc-51 like autophagy activating kinase (ULK1) and participates in LPS plus nigericin (Ng) induced pyroptotic cell death. Our results showed that TFG-deficient THP-1 macrophages exhibit higher mitochondrial ROS production. LPS/Ng stimulation triggers a much higher level of ROS and induces pyroptotic cell death. ULK1 undergoes a rapid turnover in TFG-deficient THP-1 cells. TFG forms complex with an E3 ligase, tumor necrosis factor receptor-associated factor 3 (TRAF3), and stabilizes ULK1 via disturbing ULK1-TRAF3 interaction. Knockdown of TFG facilitates the interaction of ULK1 with TRAF3 and subsequent K48-linked ULK1 ubiquitination and proteasome degradation. Rescue of ULK1 expression blocks LPS/Ng-induced cell death in TFG-deficient THP-1 macrophages. Taken together, TFG plays an essential role in LPS/Ng-induced pyroptotic cell death via regulating K48-linked ULK1 ubiquitination in macrophages.
Collapse
|
40
|
Molecular regulation of autophagosome formation. Biochem Soc Trans 2022; 50:55-69. [PMID: 35076688 PMCID: PMC9022990 DOI: 10.1042/bst20210819] [Citation(s) in RCA: 52] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Revised: 12/21/2021] [Accepted: 01/04/2022] [Indexed: 12/11/2022]
Abstract
Macroautophagy, hereafter autophagy, is a degradative process conserved among eukaryotes, which is essential to maintain cellular homeostasis. Defects in autophagy lead to numerous human diseases, including various types of cancer and neurodegenerative disorders. The hallmark of autophagy is the de novo formation of autophagosomes, which are double-membrane vesicles that sequester and deliver cytoplasmic materials to lysosomes/vacuoles for degradation. The mechanism of autophagosome biogenesis entered a molecular era with the identification of autophagy-related (ATG) proteins. Although there are many unanswered questions and aspects that have raised some controversies, enormous advances have been done in our understanding of the process of autophagy in recent years. In this review, we describe the current knowledge about the molecular regulation of autophagosome formation, with a particular focus on budding yeast and mammalian cells.
Collapse
|
41
|
Kim JH, Lee HN, Huang X, Jung H, Otegui MS, Li F, Chung T. FYVE2, a phosphatidylinositol 3-phosphate effector, interacts with the COPII machinery to control autophagosome formation in Arabidopsis. THE PLANT CELL 2022; 34:351-373. [PMID: 34718777 PMCID: PMC8846182 DOI: 10.1093/plcell/koab263] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Accepted: 10/26/2021] [Indexed: 06/13/2023]
Abstract
Autophagy is an intracellular trafficking mechanism by which cytosolic macromolecules and organelles are sequestered into autophagosomes for degradation inside the vacuole. In various eukaryotes including yeast, metazoans, and plants, the precursor of the autophagosome, termed the phagophore, nucleates in the vicinity of the endoplasmic reticulum (ER) with the participation of phosphatidylinositol 3-phosphate (PI3P) and the coat protein complex II (COPII). Here we show that Arabidopsis thaliana FYVE2, a plant-specific PI3P-binding protein, provides a functional link between the COPII machinery and autophagy. FYVE2 interacts with the small GTPase Secretion-associated Ras-related GTPase 1 (SAR1), which is essential for the budding of COPII vesicles. FYVE2 also interacts with ATG18A, another PI3P effector on the phagophore membrane. Fluorescently tagged FYVE2 localized to autophagic membranes near the ER and was delivered to vacuoles. SAR1 fusion proteins were also targeted to the vacuole via FYVE2-dependent autophagy. Either mutations in FYVE2 or the expression of dominant-negative mutant SAR1B proteins resulted in reduced autophagic flux and the accumulation of autophagic organelles. We propose that FYVE2 regulates autophagosome biogenesis through its interaction with ATG18A and the COPII machinery, acting downstream of ATG2.
Collapse
Affiliation(s)
- Jeong Hun Kim
- Department of Biological Sciences, Pusan National University, Busan 46241, Republic of Korea
| | - Han Nim Lee
- Department of Biological Sciences, Pusan National University, Busan 46241, Republic of Korea
- Department of Botany and Center for Quantitative Cell Imaging, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - Xiao Huang
- College of Life Sciences, South China Agricultural University, Guangzhou 510642, P. R. China
| | - Hyera Jung
- Department of Biological Sciences, Pusan National University, Busan 46241, Republic of Korea
| | - Marisa S Otegui
- Department of Botany and Center for Quantitative Cell Imaging, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - Faqiang Li
- College of Life Sciences, South China Agricultural University, Guangzhou 510642, P. R. China
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, South China Agricultural University, Guangzhou 510642, P. R. China
- Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, South China Agricultural University, Guangzhou 510642, P. R. China
| | - Taijoon Chung
- Department of Biological Sciences, Pusan National University, Busan 46241, Republic of Korea
- Institute of Systems Biology, Pusan National University, Busan 46241, Republic of Korea
| |
Collapse
|
42
|
Moreira DDP, Suzuki AM, Silva ALTE, Varella-Branco E, Meneghetti MCZ, Kobayashi GS, Fogo M, Ferrari MDFR, Cardoso RR, Lourenço NCV, Griesi-Oliveira K, Zachi EC, Bertola DR, Weinmann KDS, de Lima MA, Nader HB, Sertié AL, Passos-Bueno MR. Neuroprogenitor Cells From Patients With TBCK Encephalopathy Suggest Deregulation of Early Secretory Vesicle Transport. Front Cell Neurosci 2022; 15:803302. [PMID: 35095425 PMCID: PMC8793280 DOI: 10.3389/fncel.2021.803302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Accepted: 12/15/2021] [Indexed: 11/13/2022] Open
Abstract
Biallelic pathogenic variants in TBCK cause encephaloneuropathy, infantile hypotonia with psychomotor retardation, and characteristic facies 3 (IHPRF3). The molecular mechanisms underlying its neuronal phenotype are largely unexplored. In this study, we reported two sisters, who harbored biallelic variants in TBCK and met diagnostic criteria for IHPRF3. We provided evidence that TBCK may play an important role in the early secretory pathway in neuroprogenitor cells (iNPC) differentiated from induced pluripotent stem cells (iPSC). Lack of functional TBCK protein in iNPC is associated with impaired endoplasmic reticulum-to-Golgi vesicle transport and autophagosome biogenesis, as well as altered cell cycle progression and severe impairment in the capacity of migration. Alteration in these processes, which are crucial for neurogenesis, neuronal migration, and cytoarchitecture organization, may represent an important causative mechanism of both neurodevelopmental and neurodegenerative phenotypes observed in IHPRF3. Whether reduced mechanistic target of rapamycin (mTOR) signaling is secondary to impaired TBCK function over other secretory transport regulators still needs further investigation.
Collapse
Affiliation(s)
- Danielle de Paula Moreira
- Centro de Pesquisas Sobre o Genoma Humano e Células-Tronco, Instituto de Biociências, Universidade de São Paulo, São Paulo, Brazil
| | - Angela May Suzuki
- Centro de Pesquisas Sobre o Genoma Humano e Células-Tronco, Instituto de Biociências, Universidade de São Paulo, São Paulo, Brazil
| | | | - Elisa Varella-Branco
- Centro de Pesquisas Sobre o Genoma Humano e Células-Tronco, Instituto de Biociências, Universidade de São Paulo, São Paulo, Brazil
| | | | - Gerson Shigeru Kobayashi
- Centro de Pesquisas Sobre o Genoma Humano e Células-Tronco, Instituto de Biociências, Universidade de São Paulo, São Paulo, Brazil
| | - Mariana Fogo
- Centro de Pesquisas Sobre o Genoma Humano e Células-Tronco, Instituto de Biociências, Universidade de São Paulo, São Paulo, Brazil
- Instituto de Ensino e Pesquisa Albert Einstein, Albert Einstein Hospital, São Paulo, Brazil
| | | | - Rafaela Regina Cardoso
- Departamento de Genética e Biologia Evolutiva, Instituto de Biociências, Universidade de São Paulo, São Paulo, Brazil
| | - Naila Cristina Vilaça Lourenço
- Centro de Pesquisas Sobre o Genoma Humano e Células-Tronco, Instituto de Biociências, Universidade de São Paulo, São Paulo, Brazil
| | - Karina Griesi-Oliveira
- Centro de Pesquisas Sobre o Genoma Humano e Células-Tronco, Instituto de Biociências, Universidade de São Paulo, São Paulo, Brazil
- Instituto de Ensino e Pesquisa Albert Einstein, Albert Einstein Hospital, São Paulo, Brazil
| | - Elaine Cristina Zachi
- Centro de Pesquisas Sobre o Genoma Humano e Células-Tronco, Instituto de Biociências, Universidade de São Paulo, São Paulo, Brazil
| | - Débora Romeo Bertola
- Centro de Pesquisas Sobre o Genoma Humano e Células-Tronco, Instituto de Biociências, Universidade de São Paulo, São Paulo, Brazil
- Instituto da Criança do Hospital das Clínicas, Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
| | - Karina de Souza Weinmann
- Centro de Pesquisas Sobre o Genoma Humano e Células-Tronco, Instituto de Biociências, Universidade de São Paulo, São Paulo, Brazil
| | - Marcelo Andrade de Lima
- Departamento de Bioquímica, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Helena Bonciani Nader
- Departamento de Bioquímica, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Andrea Laurato Sertié
- Instituto de Ensino e Pesquisa Albert Einstein, Albert Einstein Hospital, São Paulo, Brazil
| | - Maria Rita Passos-Bueno
- Centro de Pesquisas Sobre o Genoma Humano e Células-Tronco, Instituto de Biociências, Universidade de São Paulo, São Paulo, Brazil
- *Correspondence: Maria Rita Passos-Bueno,
| |
Collapse
|
43
|
Focus on the Small GTPase Rab1: A Key Player in the Pathogenesis of Parkinson's Disease. Int J Mol Sci 2021; 22:ijms222112087. [PMID: 34769517 PMCID: PMC8584362 DOI: 10.3390/ijms222112087] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 11/04/2021] [Accepted: 11/06/2021] [Indexed: 12/19/2022] Open
Abstract
Parkinson’s disease (PD) is the second most frequent neurodegenerative disease. It is characterized by the loss of dopaminergic neurons in the substantia nigra and the formation of large aggregates in the survival neurons called Lewy bodies, which mainly contain α-synuclein (α-syn). The cause of cell death is not known but could be due to mitochondrial dysfunction, protein homeostasis failure, and alterations in the secretory/endolysosomal/autophagic pathways. Survival nigral neurons overexpress the small GTPase Rab1. This protein is considered a housekeeping Rab that is necessary to support the secretory pathway, the maintenance of the Golgi complex structure, and the regulation of macroautophagy from yeast to humans. It is also involved in signaling, carcinogenesis, and infection for some pathogens. It has been shown that it is directly linked to the pathogenesis of PD and other neurodegenerative diseases. It has a protective effect against α–σψν toxicity and has recently been shown to be a substrate of LRRK2, which is the most common cause of familial PD and the risk of sporadic disease. In this review, we analyze the key aspects of Rab1 function in dopamine neurons and its implications in PD neurodegeneration/restauration. The results of the current and former research support the notion that this GTPase is a good candidate for therapeutic strategies.
Collapse
|
44
|
Lee JE, Kim N, Jung M, Mun JY, Yoo JY. SHISA5/SCOTIN restrains spontaneous autophagy induction by blocking contact between the ERES and phagophores. Autophagy 2021; 18:1613-1628. [PMID: 34720018 PMCID: PMC9298459 DOI: 10.1080/15548627.2021.1994297] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
Abstract
The phagophore expands into autophagosomes in close proximity to endoplasmic reticulum (ER) exit sites (ERESs). Here, we propose that a single-pass ER transmembrane protein, SHISA5/SCOTIN, acts as an autophagy suppressor under basal condition by blocking the contact between the phagophore and ERES. HeLa cells lacking SHISA5 displayed higher levels of macroautophagy/autophagy. The enhanced autophagy in SHISA5 KO cells requires class III phosphatidylinositol 3-kinase complex I (PtdIns3K-C1) activity and functional assembly of ERES, but not ULK1 activity. A proximity ligation assay (PLA) of SEC16A (Sec16 homolog A, endoplasmic reticulum export factor)-WIPI2 (WD repeat domain, phosphoinositide interacting 2) and SEC31A (Sec31 homolog A, COPII coat complex component)-MAP1LC3B/LC3B (microtubule-associated protein 1 light chain 3 beta) demonstrated that contact between the ERES and phagophore increased in SHISA5 KO cells, and the cytosolic domain of SHISA5 was sufficient to rescue this phenotype. Close proximity between ERES and phagophore in SHISA5 KO cells was also visualized by performing an ultrastructure correlative image analysis of SEC31A associated with LC3-positive membranes. Furthermore, we observed that SHISA5 was located near ERES under basal conditions, but displaced away from ERES under autophagy-inducing conditions. These data suggest that SHISA5 functions to block spontaneous contact between ERES and phagophore, and the blockage effect of SHISA5 should be relieved for the proper induction of autophagy.
Collapse
Affiliation(s)
- Jee-Eun Lee
- Department of Life Sciences, Pohang University of Science and Technology, Pohang, Republic of Korea
| | - Nari Kim
- Department of Life Sciences, Pohang University of Science and Technology, Pohang, Republic of Korea
| | - Minkyo Jung
- Neural Circuit Research Group, Korea Brain Research Institute, Daegu, Republic of Korea
| | - Ji-Young Mun
- Neural Circuit Research Group, Korea Brain Research Institute, Daegu, Republic of Korea
| | - Joo-Yeon Yoo
- Department of Life Sciences, Pohang University of Science and Technology, Pohang, Republic of Korea
| |
Collapse
|
45
|
Raudenska M, Balvan J, Masarik M. Crosstalk between autophagy inhibitors and endosome-related secretory pathways: a challenge for autophagy-based treatment of solid cancers. Mol Cancer 2021; 20:140. [PMID: 34706732 PMCID: PMC8549397 DOI: 10.1186/s12943-021-01423-6] [Citation(s) in RCA: 47] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Accepted: 09/11/2021] [Indexed: 01/18/2023] Open
Abstract
Autophagy is best known for its role in organelle and protein turnover, cell quality control, and metabolism. The autophagic machinery has, however, also adapted to enable protein trafficking and unconventional secretory pathways so that organelles (such as autophagosomes and multivesicular bodies) delivering cargo to lysosomes for degradation can change their mission from fusion with lysosomes to fusion with the plasma membrane, followed by secretion of the cargo from the cell. Some factors with key signalling functions do not enter the conventional secretory pathway but can be secreted in an autophagy-mediated manner.Positive clinical results of some autophagy inhibitors are encouraging. Nevertheless, it is becoming clear that autophagy inhibition, even within the same cancer type, can affect cancer progression differently. Even next-generation inhibitors of autophagy can have significant non-specific effects, such as impacts on endosome-related secretory pathways and secretion of extracellular vesicles (EVs). Many studies suggest that cancer cells release higher amounts of EVs compared to non-malignant cells, which makes the effect of autophagy inhibitors on EVs secretion highly important and attractive for anticancer therapy. In this review article, we discuss how different inhibitors of autophagy may influence the secretion of EVs and summarize the non-specific effects of autophagy inhibitors with a focus on endosome-related secretory pathways. Modulation of autophagy significantly impacts not only the quantity of EVs but also their content, which can have a deep impact on the resulting pro-tumourigenic or anticancer effect of autophagy inhibitors used in the antineoplastic treatment of solid cancers.
Collapse
Affiliation(s)
- Martina Raudenska
- Department of Physiology, Faculty of Medicine, Masaryk University, Kamenice 5, CZ-625 00, Brno, Czech Republic
- Department of Chemistry and Biochemistry, Mendel University in Brno, Zemedelska 1, CZ-613 00, Brno, Czech Republic
- Department of Pathological Physiology, Faculty of Medicine, Masaryk University, Kamenice 5, CZ-625 00, Brno, Czech Republic
| | - Jan Balvan
- Department of Physiology, Faculty of Medicine, Masaryk University, Kamenice 5, CZ-625 00, Brno, Czech Republic
- Department of Chemistry and Biochemistry, Mendel University in Brno, Zemedelska 1, CZ-613 00, Brno, Czech Republic
- Department of Pathological Physiology, Faculty of Medicine, Masaryk University, Kamenice 5, CZ-625 00, Brno, Czech Republic
| | - Michal Masarik
- Department of Physiology, Faculty of Medicine, Masaryk University, Kamenice 5, CZ-625 00, Brno, Czech Republic.
- Department of Chemistry and Biochemistry, Mendel University in Brno, Zemedelska 1, CZ-613 00, Brno, Czech Republic.
- Department of Pathological Physiology, Faculty of Medicine, Masaryk University, Kamenice 5, CZ-625 00, Brno, Czech Republic.
- BIOCEV, First Faculty of Medicine, Charles University, Prumyslova 595, CZ-252 50, Vestec, Czech Republic.
- Center for Advanced Functional Nanorobots, Department of Inorganic Chemistry, Faculty of Chemical Technology, University of Chemistry and Technology in Prague, Technická 5, CZ-166 28, Prague, Czech Republic.
| |
Collapse
|
46
|
Lenoir G, D'Ambrosio JM, Dieudonné T, Čopič A. Transport Pathways That Contribute to the Cellular Distribution of Phosphatidylserine. Front Cell Dev Biol 2021; 9:737907. [PMID: 34540851 PMCID: PMC8440936 DOI: 10.3389/fcell.2021.737907] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Accepted: 08/10/2021] [Indexed: 12/05/2022] Open
Abstract
Phosphatidylserine (PS) is a negatively charged phospholipid that displays a highly uneven distribution within cellular membranes, essential for establishment of cell polarity and other processes. In this review, we discuss how combined action of PS biosynthesis enzymes in the endoplasmic reticulum (ER), lipid transfer proteins (LTPs) acting within membrane contact sites (MCS) between the ER and other compartments, and lipid flippases and scramblases that mediate PS flip-flop between membrane leaflets controls the cellular distribution of PS. Enrichment of PS in specific compartments, in particular in the cytosolic leaflet of the plasma membrane (PM), requires input of energy, which can be supplied in the form of ATP or by phosphoinositides. Conversely, coupling between PS synthesis or degradation, PS flip-flop and PS transfer may enable PS transfer by passive flow. Such scenario is best documented by recent work on the formation of autophagosomes. The existence of lateral PS nanodomains, which is well-documented in the case of the PM and postulated for other compartments, can change the steepness or direction of PS gradients between compartments. Improvements in cellular imaging of lipids and membranes, lipidomic analysis of complex cellular samples, reconstitution of cellular lipid transport reactions and high-resolution structural data have greatly increased our understanding of cellular PS homeostasis. Our review also highlights how budding yeast has been instrumental for our understanding of the organization and transport of PS in cells.
Collapse
Affiliation(s)
- Guillaume Lenoir
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell, Gif-sur-Yvette, France
| | - Juan Martín D'Ambrosio
- Centre de Recherche en Biologie Cellulaire de Montpellier (CRBM), Université de Montpellier, CNRS, Montpellier, France
| | - Thibaud Dieudonné
- Danish Research Institute of Translational Neuroscience - DANDRITE, Nordic EMBL Partnership for Molecular Medicine, Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
| | - Alenka Čopič
- Centre de Recherche en Biologie Cellulaire de Montpellier (CRBM), Université de Montpellier, CNRS, Montpellier, France
| |
Collapse
|
47
|
Sun LX, Qian H, Liu MY, Wu MH, Wei YY, Zhu XM, Lu JP, Lin FC, Liu XH. Endosomal sorting complexes required for transport-0 (ESCRT-0) are essential for fungal development, pathogenicity, autophagy and ER-phagy in Magnaporthe oryzae. Environ Microbiol 2021; 24:1076-1092. [PMID: 34472190 DOI: 10.1111/1462-2920.15753] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Revised: 08/28/2021] [Accepted: 08/29/2021] [Indexed: 12/23/2022]
Abstract
Magnaporthe oryzae is an important plant pathogen that causes rice blast. Hse1 and Vps27 are components of ESCRT-0 involved in the multivesicular body (MVB) sorting pathway and biogenesis. To date, the biological functions of ESCRT-0 in M. oryzae have not been determined. In this study, we identified and characterized Hse1 and Vps27 in M. oryzae. Disruption of MoHse1 and MoVps27 caused pleiotropic defects in growth, conidiation, sexual development and pathogenicity, thereby resulting in loss of virulence in rice and barley leaves. Disruption of MoHse1 and MoVps27 triggered increased lipidation of MoAtg8 and degradation of GFP-MoAtg8, indicating that ESCRT-0 is involved in the regulation of autophagy. ESCRT-0 was determined to interact with coat protein complex II (COPII), a regulator functioning in homeostasis of the endoplasmic reticulum (ER homeostasis), and disruption of MoHse1 and MoVps27 also blocked activation of the unfolded protein response (UPR) and autophagy of the endoplasmic reticulum (ER-phagy). Overall, our results indicate that ESCRT-0 plays critical roles in regulating fungal development, virulence, autophagy and ER-phagy in M. oryzae.
Collapse
Affiliation(s)
- Li-Xiao Sun
- State Key Laboratory for Managing Biotic and Chemical Treats to the Quality and Safety of Agro-products, Institute of Biotechnology, Zhejiang University, Hangzhou, 310058, China
| | - Hui Qian
- State Key Laboratory for Managing Biotic and Chemical Treats to the Quality and Safety of Agro-products, Institute of Biotechnology, Zhejiang University, Hangzhou, 310058, China
| | - Meng-Yu Liu
- State Key Laboratory for Managing Biotic and Chemical Treats to the Quality and Safety of Agro-products, Institute of Biotechnology, Zhejiang University, Hangzhou, 310058, China
| | - Ming-Hua Wu
- State Key Laboratory for Managing Biotic and Chemical Treats to the Quality and Safety of Agro-products, Institute of Biotechnology, Zhejiang University, Hangzhou, 310058, China
| | - Yun-Yun Wei
- State Key Laboratory for Managing Biotic and Chemical Treats to the Quality and Safety of Agro-products, Institute of Biotechnology, Zhejiang University, Hangzhou, 310058, China
| | - Xue-Ming Zhu
- State Key Laboratory for Managing Biotic and Chemical Treats to the Quality and Safety of Agro-products, Institute of Plant Protection and Microbiology, Zhejiang Academy of Agricultural Sciences, Hangzhou, 310021, China
| | - Jian-Ping Lu
- College of Life Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Fu-Cheng Lin
- State Key Laboratory for Managing Biotic and Chemical Treats to the Quality and Safety of Agro-products, Institute of Biotechnology, Zhejiang University, Hangzhou, 310058, China.,State Key Laboratory for Managing Biotic and Chemical Treats to the Quality and Safety of Agro-products, Institute of Plant Protection and Microbiology, Zhejiang Academy of Agricultural Sciences, Hangzhou, 310021, China
| | - Xiao-Hong Liu
- State Key Laboratory for Managing Biotic and Chemical Treats to the Quality and Safety of Agro-products, Institute of Biotechnology, Zhejiang University, Hangzhou, 310058, China
| |
Collapse
|
48
|
Methods for Assessing the Regulation of a Kinase by the Rab GTPase Ypt1. Methods Mol Biol 2021. [PMID: 34453719 DOI: 10.1007/978-1-0716-1346-7_14] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
Abstract
COPII coated vesicles that bud from the endoplasmic reticulum (ER) normally traffic to the Golgi. However, during starvation, COPII vesicles are redirected to the macroautophagy pathway where they become a membrane source for autophagosomes. Phosphorylation of the coat by the casein kinase 1 (CK1), Hrr25, is a prerequisite for vesicle uncoating and membrane fusion. CK1 family members were initially thought to be constitutively active kinases that are regulated through their subcellular localization. Recent studies, however, have shown that the Rab GTPase Ypt1 binds to and activates Hrr25 (CK1δ in mammals) to spatially regulate its kinase activity. Consistent with a direct role for Hrr25 in macroautophagy, hrr25and ypt1mutants are defective in autophagosome biogenesis. These studies have provided insights into how the itinerary of COPII vesicles is coordinated on two different trafficking pathways.
Collapse
|
49
|
Nakamura TS, Suda Y, Muneshige K, Fujieda Y, Okumura Y, Inoue I, Tanaka T, Takahashi T, Nakanishi H, Gao XD, Okada Y, Neiman AM, Tachikawa H. Suppression of Vps13 adaptor protein mutants reveals a central role for PI4P in regulating prospore membrane extension. PLoS Genet 2021; 17:e1009727. [PMID: 34407079 PMCID: PMC8372973 DOI: 10.1371/journal.pgen.1009727] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Accepted: 07/20/2021] [Indexed: 01/19/2023] Open
Abstract
Vps13 family proteins are proposed to function in bulk lipid transfer between membranes, but little is known about their regulation. During sporulation of Saccharomyces cerevisiae, Vps13 localizes to the prospore membrane (PSM) via the Spo71–Spo73 adaptor complex. We previously reported that loss of any of these proteins causes PSM extension and subsequent sporulation defects, yet their precise function remains unclear. Here, we performed a genetic screen and identified genes coding for a fragment of phosphatidylinositol (PI) 4-kinase catalytic subunit and PI 4-kinase noncatalytic subunit as multicopy suppressors of spo73Δ. Further genetic and cytological analyses revealed that lowering PI4P levels in the PSM rescues the spo73Δ defects. Furthermore, overexpression of VPS13 and lowering PI4P levels synergistically rescued the defect of a spo71Δ spo73Δ double mutant, suggesting that PI4P might regulate Vps13 function. In addition, we show that an N-terminal fragment of Vps13 has affinity for the endoplasmic reticulum (ER), and ER-plasma membrane (PM) tethers localize along the PSM in a manner dependent on Vps13 and the adaptor complex. These observations suggest that Vps13 and the adaptor complex recruit ER-PM tethers to ER-PSM contact sites. Our analysis revealed that involvement of a phosphoinositide, PI4P, in regulation of Vps13, and also suggest that distinct contact site proteins function cooperatively to promote de novo membrane formation. Vps13 family proteins are conserved lipid transfer proteins that function at organelle contact sites and have been implicated in a number of different neurological diseases. In the yeast Saccharomyces cerevisiae, Vps13 is encoded by a single gene and is localized to various contact sites by interaction with different adaptor proteins and/or lipids, however its regulation is yet to be clarified. We have previously shown that during the developmental process of sporulation, Vps13 is recruited to de novo membrane structures called prospore membranes (PSMs) by a specific adaptor complex, and Vps13 and its adaptors are required for PSM extension. Here we reveal that loss of an adaptor can be overcome by lowering phosphatidylinositol-4-phosphate (PI4P) levels, either by inhibiting PI 4-kinase on the PSM or recruiting PI 4-phospatase to the PSM and that PI4P levels in the PSM affect Vps13 function. Further, we show that Vps13 forms endoplasmic reticulum (ER)-PSM contact sites, that ER-plasma membrane tethering proteins are recruited to ER-PSM contacts, and these proteins may function in conjunction with Vps13. Thus, our work shines light on both the mechanisms of intracellular remodeling and the function of this important class of lipid transfer proteins.
Collapse
Affiliation(s)
- Tsuyoshi S. Nakamura
- Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan
- Cell Biology Center, Institute of Innovative Research, Tokyo Institute of Technology, Kanagawa, Japan
| | - Yasuyuki Suda
- Department of Molecular Cell Biology, Graduate School of Comprehensive Human Sciences and Institute of Basic Medical Sciences, University of Tsukuba, Ibaraki, Japan
- Live Cell Super-Resolution Imaging Research Team, RIKEN Center for Advanced Photonics, Saitama, Japan
| | - Kenji Muneshige
- Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - Yuji Fujieda
- Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - Yuuya Okumura
- Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - Ichiro Inoue
- Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - Takayuki Tanaka
- Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - Tetsuo Takahashi
- Laboratory of Glycobiology and Glycotechnology, Department of Applied Biochemistry, School of Engineering, Tokai University, Kanagawa, Japan
| | - Hideki Nakanishi
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China
| | - Xiao-Dong Gao
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China
| | - Yasushi Okada
- Laboratory for Cell Dynamics Observation, Center for Biosystems Dynamics Research, RIKEN, Osaka, Japan
- Department of Physics and Universal Biology Institute, Graduate School of Science, The University of Tokyo, Tokyo, Japan
- Department of Physics, Universal Biology Institute, and the International Research Center for Neurointelligence (WPI-IRCN), The University of Tokyo, Tokyo, Japan
| | - Aaron M. Neiman
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, New York, United States of America
| | - Hiroyuki Tachikawa
- Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan
- Collaborative Research Institute for Innovative Microbiology, The University of Tokyo, Tokyo, Japan
- * E-mail:
| |
Collapse
|
50
|
Noda NN. Atg2 and Atg9: Intermembrane and interleaflet lipid transporters driving autophagy. Biochim Biophys Acta Mol Cell Biol Lipids 2021; 1866:158956. [PMID: 33932584 DOI: 10.1016/j.bbalip.2021.158956] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2021] [Revised: 04/03/2021] [Accepted: 04/08/2021] [Indexed: 12/14/2022]
Abstract
Autophagy, an intracellular degradation mechanism, involves de novo generation of autophagosomes that sequester and deliver cytoplasmic components to the lysosome for degradation. The mechanism behind autophagosomal membrane expansion has been a longstanding enigma in this field. Recent structural and biochemical analyses have revealed that two mysterious autophagy-related (Atg) proteins, Atg2 and Atg9, are novel types of intermembrane and interleaflet lipid transporters, respectively. This review summarizes recent discoveries surrounding Atg2 and Atg9 as a lipid transporter and discusses the molecular mechanism of autophagosomal membrane expansion driven by collaboration between these two lipid transporters.
Collapse
Affiliation(s)
- Nobuo N Noda
- Institute of Microbial Chemistry (BIKAKEN), Tokyo, Japan.
| |
Collapse
|