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Gao B, Yu B, Huang X, Li H, Jia Y, Wang M, Lu Y, Zhang X, Li W. Cadmium and calcium ions' effects on the growth of Pleurotus ostreatus mycelia are related to phosphatidylethanolamine content. Fungal Biol 2024; 128:2190-2196. [PMID: 39384288 DOI: 10.1016/j.funbio.2024.08.012] [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: 03/17/2024] [Revised: 08/26/2024] [Accepted: 08/29/2024] [Indexed: 10/11/2024]
Abstract
Heavy metal Cd2+ can easily be accumulated by fungi, causing significant stress, with the fungal cell membrane being one of the primary targets. However, the understanding of the mechanisms behind this stress remains limited. This study investigated the changes in membrane lipid molecules of Pleurotus ostreatus mycelia under Cd2+ stress and the antagonistic effect of Ca2+ on this stress. Cd2+ in the growth media significantly inhibited mycelial growth, with increasing intensity at higher concentrations. The addition of Ca2+ mitigated this Cd2+-induced growth inhibition. Lipidomic analysis showed that Cd2+ reduced membrane lipid content and altered lipid composition, while Ca2+ counteracted these changes. The effects of both Cd2+ and Ca2+ on lipids are dose dependent and phosphatidylethanolamine appeared most affected. Cd2+ also caused a phosphatidylcholine/phosphatidylethanolamine ratio increase at high concentrations, but Ca2+ helped maintain normal levels. The acyl chain length and unsaturation of lipids remained unaffected, suggesting Cd2+ doesn't alter acyl chain structure of lipids. These findings suggest that Cd2+ may affect the growth of mycelia by inhibiting the synthesis of membrane lipids, particular the synthesis of phosphatidylethanolamine, providing novel insights into the mechanisms of Cd2+ stress in fungi and the role of Ca2+ in mitigating the stress.
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Affiliation(s)
- Bo Gao
- Germplasm Bank of Wild Species & Yunnan Key Laboratory of Crop Wild Relatives Omics, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, Yunnan, China; University of Chinese Academy of Sciences, Beijing, 100039, China; College of Biological and Agricultural Sciences, Honghe University, Mengzi, 661199, Yunnan, China
| | - Buzhu Yu
- Germplasm Bank of Wild Species & Yunnan Key Laboratory of Crop Wild Relatives Omics, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, Yunnan, China; Yuxi Normal University, Yuxi, 653100, Yunnan, China
| | - Xing Huang
- Germplasm Bank of Wild Species & Yunnan Key Laboratory of Crop Wild Relatives Omics, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, Yunnan, China
| | - He Li
- College of Biological and Agricultural Sciences, Honghe University, Mengzi, 661199, Yunnan, China
| | - Yanxia Jia
- Germplasm Bank of Wild Species & Yunnan Key Laboratory of Crop Wild Relatives Omics, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, Yunnan, China
| | - Mulan Wang
- Germplasm Bank of Wild Species & Yunnan Key Laboratory of Crop Wild Relatives Omics, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, Yunnan, China; Key Laboratory of Chemistry in Ethnic Medicinal Resources, Ministry of Education of China, Yunnan Minzu University, Kunming, 650504, China
| | - Yuanxue Lu
- Germplasm Bank of Wild Species & Yunnan Key Laboratory of Crop Wild Relatives Omics, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, Yunnan, China
| | - Xudong Zhang
- Germplasm Bank of Wild Species & Yunnan Key Laboratory of Crop Wild Relatives Omics, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, Yunnan, China.
| | - Weiqi Li
- Germplasm Bank of Wild Species & Yunnan Key Laboratory of Crop Wild Relatives Omics, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, Yunnan, China.
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2
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Jacomin AC, Dikic I. Membrane remodeling via ubiquitin-mediated pathways. Cell Chem Biol 2024; 31:1627-1635. [PMID: 39303699 DOI: 10.1016/j.chembiol.2024.08.007] [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: 06/10/2024] [Revised: 07/30/2024] [Accepted: 08/19/2024] [Indexed: 09/22/2024]
Abstract
The dynamic process of membrane shaping and remodeling plays a vital role in cellular functions, with proteins and cellular membranes interacting intricately to adapt to various cellular needs and environmental cues. Ubiquitination-a posttranslational modification-was shown to be essential in regulating membrane structure and shape. It influences virtually all pathways relying on cellular membranes, such as endocytosis and autophagy by directing protein degradation, sorting, and oligomerization. Ubiquitin is mostly known as a protein modifier; however, it was reported that ubiquitin and ubiquitin-like proteins can associate directly with lipids, affecting membrane curvature and dynamics. In this review, we summarize some of the current knowledge on ubiquitin-mediated membrane remodeling in the context of endocytosis, autophagy, and ER-phagy.
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Affiliation(s)
- Anne-Claire Jacomin
- Goethe University Frankfurt, Medical Faculty, Institute of Biochemistry II, Theodor-Stern-Kai 7, 60590 Frankfurt Am Main, Germany
| | - Ivan Dikic
- Goethe University Frankfurt, Medical Faculty, Institute of Biochemistry II, Theodor-Stern-Kai 7, 60590 Frankfurt Am Main, Germany; Goethe University Frankfurt, Buchmann Institute for Molecular Life Sciences, Max-von-Laue-Strasse 15, 60438 Frankfurt Am Main, Germany.
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3
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Zhou XZ, Huang P, Wu YK, Yu JB, Sun J. Autophagy in benign prostatic hyperplasia: insights and therapeutic potential. BMC Urol 2024; 24:198. [PMID: 39261818 PMCID: PMC11391623 DOI: 10.1186/s12894-024-01585-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2024] [Accepted: 08/30/2024] [Indexed: 09/13/2024] Open
Abstract
Autophagy is a cellular homeostatic mechanism characterized by cyclic degradation. It plays an essential role in maintaining cellular quality and survival by eliminating dysfunctional cellular components. This process is pivotal in various pathophysiological processes. Benign prostatic hyperplasia (BPH) is a common urological disorder in middle-aged and elderly men. It frequently presents as lower urinary tract symptoms due to an increase in epithelial and stromal cells surrounding the prostatic urethra. The precise pathogenesis of BPH is complex. In recent years, research on autophagy in BPH has gained significant momentum, with accumulating evidence indicating its crucial role in the onset and progression of the disease. This review aims to outline the various roles of autophagy in BPH and elucidate potential therapeutic strategies targeting autophagy for managing BPH.
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Affiliation(s)
- Xian-Zhao Zhou
- Department of Andrology, Third Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, 310005, China
| | - Pei Huang
- Department of Andrology, Third Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, 310005, China
| | - Yao-Kan Wu
- Department of Andrology, Third Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, 310005, China
| | - Jin-Ben Yu
- Department of Andrology, Third Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, 310005, China
| | - Jie Sun
- Department of Andrology, Third Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, 310005, China.
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4
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Zhao L, Qiu J, Zhang J, Li A, Wang G. Apoptosis and Oxidative Stress in Human Intestinal Epithelial Caco-2 Cells Caused by Marine Phycotoxin Azaspiracid-2. Toxins (Basel) 2024; 16:381. [PMID: 39330839 PMCID: PMC11435587 DOI: 10.3390/toxins16090381] [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: 07/18/2024] [Revised: 08/12/2024] [Accepted: 08/29/2024] [Indexed: 09/28/2024] Open
Abstract
When humans consume seafood contaminated by lipophilic polyether phycotoxins, such as azaspiracids (AZAs), the toxins are mainly leached and absorbed in the small intestine, potentially causing intestinal damage. In this study, human intestinal epithelial Caco-2 cells were used to investigate the adverse effects of azaspiracid-2 (AZA-2) on human intestinal epithelial cells. Cell viability, apoptosis, oxidative damage and mitochondrial ultrastructure were investigated, and ribonucleic acid sequence (RNA-seq) analysis was applied to explore the potential mechanisms of AZA-2 toxicity to Caco-2 cells. Results showed that AZA-2 significantly reduced the proliferation of Caco-2 cells in a concentration-dependent response, and the 48 h EC50 of AZA-2 was 12.65 nmol L-1. AZA-2 can induce apoptosis in Caco-2 cells in a dose-dependent manner. Visible mitochondrial swelling, cristae disintegration, membrane rupture and autophagy were observed in Caco-2 cells exposed to AZA-2. Reactive oxygen species (ROS) and malondialdehyde (MDA) content were significantly increased in Caco-2 cells after 48 h of exposure to 1 and 10 nmol L-1 of AZA-2. Transcriptome analysis showed that KEGG pathways related to cellular oxidative damage and lipid metabolism were affected, mainly including mitophagy, oxidative phosphorylation, cholesterol metabolism, vitamin digestion and absorption, bile secretion and the peroxisome proliferator-activated receptor signaling pathway. The cytotoxic effects of AZA-2 on Caco-2 cells may be associated with ROS-mediated autophagy and apoptosis in mitochondrial cells. Results of this study improve understanding of the cytotoxicity and molecular mechanisms of AZA-2 on Caco-2 cells, which is significant for protecting human health.
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Affiliation(s)
- Liye Zhao
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China; (L.Z.); (J.Z.); (G.W.)
| | - Jiangbing Qiu
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China; (L.Z.); (J.Z.); (G.W.)
- Key Laboratory of Marine Environment and Ecology, Ocean University of China, Ministry of Education, Qingdao 266100, China
| | - Jingrui Zhang
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China; (L.Z.); (J.Z.); (G.W.)
| | - Aifeng Li
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China; (L.Z.); (J.Z.); (G.W.)
- Key Laboratory of Marine Environment and Ecology, Ocean University of China, Ministry of Education, Qingdao 266100, China
| | - Guixiang Wang
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China; (L.Z.); (J.Z.); (G.W.)
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5
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Ohashi K, Otomo T. Structural Analyses of a GABARAP~ATG3 Conjugate Uncover a Novel Non-covalent Ubl-E2 Backside Interaction. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.08.14.607425. [PMID: 39185234 PMCID: PMC11343110 DOI: 10.1101/2024.08.14.607425] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 08/27/2024]
Abstract
Members of the ATG8 family of ubiquitin-like proteins (Ubls) are conjugated to phosphatidylethanolamine (PE) in the autophagosomal membrane, where they recruit degradation substrates and facilitate membrane biogenesis. Despite this well-characterized function, the mechanisms underlying the lipidation process, including the action of the E2 enzyme ATG3, remain incompletely understood. Here, we report the crystal structure of human ATG3 conjugated to the mammalian ATG8 protein GABARAP via an isopeptide bond, mimicking the Ubl~E2 thioester intermediate. In this structure, the GABARAP~ATG3 conjugate adopts an open configuration with minimal contacts between the two proteins. Notably, the crystal lattice reveals non-covalent contacts between GABARAP and the backside of ATG3's E2 catalytic center, resulting in the formation of a helical filament of the GABARAP~ATG3 conjugate. While similar filament formations have been observed with canonical Ub~E2 conjugates, the E2 backside-binding interface of GABARAP is distinct from those of Ub/Ubl proteins and overlaps with the binding site for LC3 interacting region (LIR) peptides. NMR analysis confirms the presence of this non-covalent interaction in solution, and mutagenesis experiments demonstrate the involvement of the E2 backside in PE conjugation. These findings highlight the critical role of the E2 backside in the lipidation process and suggest evolutionary adaptations in the unique E2 enzyme ATG3.
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Affiliation(s)
- Kazuto Ohashi
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, 10550 North Torrey Pines Rd, La Jolla, CA 92037, USA
- Institute for Molecular and Cellular Regulation, Gunma University, 371-8512 Gunma, Japan
| | - Takanori Otomo
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, 10550 North Torrey Pines Rd, La Jolla, CA 92037, USA
- San Diego Biomedical Research Institute, 3525 John Hopkins Ct, San Diego, CA 92121, USA
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6
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Hao EJ, Zhao Y, Yu M, Li XJ, Wang KX, Su FY, Liang YR, Wang Y, Guo HM. Discovery, Synthesis, and Activity Evaluation of Novel Five-Membered Sulfur-Containing Heterocyclic Nucleosides as Potential Anticancer Agents In Vitro and In Vivo. J Med Chem 2024. [PMID: 39016216 DOI: 10.1021/acs.jmedchem.4c00443] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/18/2024]
Abstract
A series of novel five-membered sulfur-containing heterocyclic nucleoside derivatives were designed, synthesized, and evaluated for their anticancer activities in vitro and in vivo. The structure-activity relationship studies revealed that some of them showed obvious antitumor activities in several cancer cell lines. Among them, compound 22o exhibited remarkable antiproliferative activity against HeLa cells and was more potent than cisplatin (IC50 = 2.80 vs 7.99 μM). Furthermore, mechanism studies indicated that 22o inhibited cell metastasis, induced cell apoptosis, decreased mitochondrial membrane potential, and activated autophagy through the PI3K-Akt-mTOR signaling pathway. Moreover, drug affinity responsive target stability and the cellular thermal shift assay revealed that 22o targeted RPS6 and inhibited its phosphorylation. Importantly, 22o inhibited the growth of the HeLa xenograft mouse model with a low systemic toxicity. These results indicated that 22o may serve as potent anticancer agents that merit further attention in future anticancer drug discovery.
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Affiliation(s)
- Er-Jun Hao
- State Key Laboratory of Antiviral Drugs, Pingyuan Laboratory, Key Laboratory of Green Chemical Media and Reactions, Ministry of Education, School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang 453007, China
| | - Yan Zhao
- State Key Laboratory of Antiviral Drugs, Pingyuan Laboratory, Key Laboratory of Green Chemical Media and Reactions, Ministry of Education, School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang 453007, China
| | - Min Yu
- School of Pharmacy, Fudan University, Shanghai 201203, China
| | - Xian-Jia Li
- State Key Laboratory of Antiviral Drugs, Pingyuan Laboratory, Key Laboratory of Green Chemical Media and Reactions, Ministry of Education, School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang 453007, China
| | - Ke-Xin Wang
- State Key Laboratory of Antiviral Drugs, Pingyuan Laboratory, Key Laboratory of Green Chemical Media and Reactions, Ministry of Education, School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang 453007, China
| | - Fu-Ying Su
- State Key Laboratory of Antiviral Drugs, Pingyuan Laboratory, Key Laboratory of Green Chemical Media and Reactions, Ministry of Education, School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang 453007, China
| | - Yu-Ru Liang
- Institute of Translational Medicine, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Yang Wang
- School of Pharmacy, Fudan University, Shanghai 201203, China
| | - Hai-Ming Guo
- State Key Laboratory of Antiviral Drugs, Pingyuan Laboratory, Key Laboratory of Green Chemical Media and Reactions, Ministry of Education, School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang 453007, China
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7
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Ye Y, Liang X, Wang G, Bewley MC, Hamamoto K, Liu X, Flanagan JM, Wang HG, Takahashi Y, Tian F. Identification of membrane curvature sensing motifs essential for VPS37A phagophore recruitment and autophagosome closure. Commun Biol 2024; 7:334. [PMID: 38491121 PMCID: PMC10942982 DOI: 10.1038/s42003-024-06026-7] [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: 02/06/2024] [Accepted: 03/07/2024] [Indexed: 03/18/2024] Open
Abstract
VPS37A, an ESCRT-I complex component, is required for recruiting a subset of ESCRT proteins to the phagophore for autophagosome closure. However, the mechanism by which VPS37A is targeted to the phagophore remains obscure. Here, we demonstrate that the VPS37A N-terminal domain exhibits selective interactions with highly curved membranes, mediated by two membrane-interacting motifs within the disordered regions surrounding its Ubiquitin E2 variant-like (UEVL) domain. Site-directed mutations of residues in these motifs disrupt ESCRT-I localization to the phagophore and result in defective phagophore closure and compromised autophagic flux in vivo, highlighting their essential role during autophagy. In conjunction with the UEVL domain, we postulate that these motifs guide a functional assembly of the ESCRT machinery at the highly curved tip of the phagophore for autophagosome closure. These results advance the notion that the distinctive membrane architecture of the cup-shaped phagophore spatially regulates autophagosome biogenesis.
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Affiliation(s)
- Yansheng Ye
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, Hershey, PA, 17033, USA.
| | - Xinwen Liang
- Department of Pediatrics, Division of Pediatric Hematology and Oncology, Pennsylvania State University College of Medicine, Hershey, PA, 17033, USA
| | - Guifang Wang
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, Hershey, PA, 17033, USA
| | - Maria C Bewley
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, Hershey, PA, 17033, USA
| | - Kouta Hamamoto
- Department of Pediatrics, Division of Pediatric Hematology and Oncology, Pennsylvania State University College of Medicine, Hershey, PA, 17033, USA
| | - Xiaoming Liu
- Department of Pediatrics, Division of Pediatric Hematology and Oncology, Pennsylvania State University College of Medicine, Hershey, PA, 17033, USA
| | - John M Flanagan
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, Hershey, PA, 17033, USA
| | - Hong-Gang Wang
- Department of Pediatrics, Division of Pediatric Hematology and Oncology, Pennsylvania State University College of Medicine, Hershey, PA, 17033, USA
| | - Yoshinori Takahashi
- Department of Pediatrics, Division of Pediatric Hematology and Oncology, Pennsylvania State University College of Medicine, Hershey, PA, 17033, USA.
| | - Fang Tian
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, Hershey, PA, 17033, USA.
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8
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Ye Y, Bewley MC, Wang HG, Tian F, Flanagan JM. What's in an E3: role of highly curved membranes in facilitating LC3-phosphatidylethanolamine conjugation during autophagy. Autophagy 2024; 20:709-711. [PMID: 38032155 PMCID: PMC10936649 DOI: 10.1080/15548627.2023.2288527] [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: 11/16/2023] [Revised: 11/19/2023] [Accepted: 11/20/2023] [Indexed: 12/01/2023] Open
Abstract
During autophagosome formation, ATG3, an E2-like enzyme, catalyzes the transfer of LC3-family proteins (including Atg8 in yeast and LC3- and GABARAP-subfamily members in more complex eukaryotes) from the covalent conjugated ATG3-LC3 intermediate to PE lipids in targeted membranes. A recent study has shown that the catalytically important regions of human ATG3 (hereafter referred to as ATG3), including residues 262 to 277 and 291 to 300, in cooperation with its N-terminal curvature-sensing amphipathic helix (NAH), directly interact with the membrane. These membrane interactions are functionally necessary for in vitro conjugation and in vivo cellular assays. They provide a molecular mechanism for how the membrane curvature-sensitive interaction of the NAH of ATG3 is closely coupled to its conjugase activity. Together, the data are consistent with a model in which the highly curved phagophore rims facilitate the recruitment of the ATG3-LC3 complex and promote the conjugation of LC3 to PE lipids. Mechanistically, the highly curved membranes of the phagophore rims act in much the same manner as classical E3 enzymes in the sumo/ubiquitin system, bringing substrates into proximity and rearranging the catalytic center of ATG3. Future studies will investigate how this multifaceted membrane interaction of ATG3 works with the putative E3 complex, ATG12-ATG5-ATG16L1, to promote LC3-PE conjugation.
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Affiliation(s)
- Yansheng Ye
- Department of Biochemistry and Molecular Biology, Pennsylvania State University College of Medicine, Hershey, PA, USA
| | - Maria C. Bewley
- Department of Biochemistry and Molecular Biology, Pennsylvania State University College of Medicine, Hershey, PA, USA
- Biomedical Core Facilities, Pennsylvania State University College of Medicine, Hershey, PA, USA
| | - Hong-Gang Wang
- Department of Pediatrics, Division of Pediatric Hematology and Oncology, Pennsylvania State University College of Medicine, Hershey, PA, USA
| | - Fang Tian
- Department of Biochemistry and Molecular Biology, Pennsylvania State University College of Medicine, Hershey, PA, USA
| | - John M. Flanagan
- Department of Biochemistry and Molecular Biology, Pennsylvania State University College of Medicine, Hershey, PA, USA
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9
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Rao S, Skulsuppaisarn M, Strong LM, Ren X, Lazarou M, Hurley JH, Hummer G. Three-step docking by WIPI2, ATG16L1, and ATG3 delivers LC3 to the phagophore. SCIENCE ADVANCES 2024; 10:eadj8027. [PMID: 38324698 PMCID: PMC10851258 DOI: 10.1126/sciadv.adj8027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Accepted: 01/05/2024] [Indexed: 02/09/2024]
Abstract
The covalent attachment of ubiquitin-like LC3 proteins (microtubule-associated proteins 1A/1B light chain 3) prepares the autophagic membrane for cargo recruitment. We resolve key steps in LC3 lipidation by combining molecular dynamics simulations and experiments in vitro and in cellulo. We show how the E3-like ligaseautophagy-related 12 (ATG12)-ATG5-ATG16L1 in complex with the E2-like conjugase ATG3 docks LC3 onto the membrane in three steps by (i) the phosphatidylinositol 3-phosphate effector protein WD repeat domain phosphoinositide-interacting protein 2 (WIPI2), (ii) helix α2 of ATG16L1, and (iii) a membrane-interacting surface of ATG3. Phosphatidylethanolamine (PE) lipids concentrate in a region around the thioester bond between ATG3 and LC3, highlighting residues with a possible role in the catalytic transfer of LC3 to PE, including two conserved histidines. In a near-complete pathway from the initial membrane recruitment to the LC3 lipidation reaction, the three-step targeting of the ATG12-ATG5-ATG16L1 machinery establishes a high level of regulatory control.
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Affiliation(s)
- Shanlin Rao
- Department of Theoretical Biophysics, Max Planck Institute of Biophysics, Frankfurt am Main, Germany
- Aligning Science Across Parkinson’s (ASAP) Collaborative Research Network, Chevy Chase, MD 20815, USA
| | - Marvin Skulsuppaisarn
- Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, Australia
- Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Melbourne, Victoria, Australia
| | - Lisa M. Strong
- Aligning Science Across Parkinson’s (ASAP) Collaborative Research Network, Chevy Chase, MD 20815, USA
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA
- California Institute for Quantitative Biosciences, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Xuefeng Ren
- Aligning Science Across Parkinson’s (ASAP) Collaborative Research Network, Chevy Chase, MD 20815, USA
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA
- California Institute for Quantitative Biosciences, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Michael Lazarou
- Aligning Science Across Parkinson’s (ASAP) Collaborative Research Network, Chevy Chase, MD 20815, USA
- Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, Australia
- Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Melbourne, Victoria, Australia
- Department of Medical Biology, University of Melbourne, Melbourne, Victoria, Australia
| | - James H. Hurley
- Aligning Science Across Parkinson’s (ASAP) Collaborative Research Network, Chevy Chase, MD 20815, USA
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA
- California Institute for Quantitative Biosciences, University of California, Berkeley, Berkeley, CA 94720, USA
- Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Gerhard Hummer
- Department of Theoretical Biophysics, Max Planck Institute of Biophysics, Frankfurt am Main, Germany
- Aligning Science Across Parkinson’s (ASAP) Collaborative Research Network, Chevy Chase, MD 20815, USA
- Institute of Biophysics, Goethe University Frankfurt, 60438 Frankfurt am Main, Germany
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