1
|
Wu KP, Yan ZJ, Zhuang XX, Hua JL, Li MX, Huang K, Qi YX. Dynamic structure and function of nuclear pore protein complex: Potential roles of lipid and lamins regulated nuclear membrane curvature. Int J Biol Macromol 2025; 313:144104. [PMID: 40350114 DOI: 10.1016/j.ijbiomac.2025.144104] [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: 12/16/2024] [Revised: 05/05/2025] [Accepted: 05/08/2025] [Indexed: 05/14/2025]
Abstract
The nuclear pore complex (NPC), a massive and highly sophisticated protein assembly, forms a channel embedded in the nuclear envelope (NE) of eukaryotic cells. As a critical gateway, NPC mediates the bidirectional transport of macromolecules between the cytoplasm and the nucleus. Here, we overview the structure and transport function of this protein complex, and highlight the selective barrier model of NPC transport functional modules. Nuclear membrane curvature (NMC) is a critical parameter for quantifying nuclear deformation. We discuss the mechanism by which NMC regulates dynamic NPC structure, function and distribution. Furthermore we highlight the role of two key factors, i.e. lipid composition and lamins distribution, in NMC and NPC dynamics while elucidating their regulatory mechanisms. The investigations on the dynamic structure and function of NPC modulated by NMC provide a new avenue for understanding the role of NPC in different pathological conditions. This knowledge could contribute to the development of novel therapeutic strategies.
Collapse
Affiliation(s)
- Kun-Peng Wu
- Institute of Mechanobiology & Medical Engineering, School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, 800 Dongchuan Road, Minhang, 200240 Shanghai, China
| | - Zhi-Jie Yan
- Institute of Mechanobiology & Medical Engineering, School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, 800 Dongchuan Road, Minhang, 200240 Shanghai, China
| | - Xiao-Xi Zhuang
- Institute of Mechanobiology & Medical Engineering, School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, 800 Dongchuan Road, Minhang, 200240 Shanghai, China
| | - Jin-Liang Hua
- Institute of Mechanobiology & Medical Engineering, School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, 800 Dongchuan Road, Minhang, 200240 Shanghai, China
| | - Meng-Xiao Li
- Institute of Mechanobiology & Medical Engineering, School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, 800 Dongchuan Road, Minhang, 200240 Shanghai, China
| | - Kai Huang
- Institute of Mechanobiology & Medical Engineering, School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, 800 Dongchuan Road, Minhang, 200240 Shanghai, China.
| | - Ying-Xin Qi
- Institute of Mechanobiology & Medical Engineering, School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, 800 Dongchuan Road, Minhang, 200240 Shanghai, China.
| |
Collapse
|
2
|
Campisi D, Hawkins N, Bonjour K, Wollert T. The Role of WIPI2, ATG16L1 and ATG12-ATG5 in Selective and Nonselective Autophagy. J Mol Biol 2025:169138. [PMID: 40221132 DOI: 10.1016/j.jmb.2025.169138] [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: 12/05/2024] [Revised: 02/24/2025] [Accepted: 04/07/2025] [Indexed: 04/14/2025]
Abstract
Autophagy is a conserved cellular recycling pathway that delivers damaged or superfluous cytoplasmic material to lysosomes for degradation. In response to cytotoxic stress or starvation, autophagy can also sequester bulk cytoplasm and deliver it to lysosomes to regenerate building blocks. In macroautophagy, a membrane cisterna termed phagophore that encloses autophagic cargo is generated. The formation of the phagophore depends on a conserved machinery of autophagy related proteins. The phosphatidylinositol(3)-phosphate binding protein WIPI2 facilitates the transition from phagophore initiation to phagophore expansion by recruiting the ATG12-ATG5-ATG16L1 complex to phagophores. This complex functions as an E3-ligase to conjugate ubiquitin-like ATG8 proteins to phagophore membranes, which promotes tethering of cargo to phagophore membranes, phagophore expansion, maturation and the fusion of autophagosomes with lysosomes. ATG16L1 also has important functions independently of ATG12-ATG5 in autophagy and beyond. In this review, we will summarize the functions of WIPI2 and ATG16L1 in selective and nonselective autophagy.
Collapse
Affiliation(s)
- Daniele Campisi
- Membrane Biochemistry and Transport, Institut Pasteur, Université de Paris, UMR3691 CNRS, 75015 Paris, France
| | - N'Toia Hawkins
- Membrane Biochemistry and Transport, Institut Pasteur, Université de Paris, UMR3691 CNRS, 75015 Paris, France
| | - Kennedy Bonjour
- 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
|
3
|
Kaur V, Khuntia SS, Taneja C, Chaudhuri A, Yogendran KP, Rakshit S. De-Novo Design of Actively Spinning and Gyrating Spherical Micro-Vesicles. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2025; 37:e2419716. [PMID: 40008816 DOI: 10.1002/adma.202419716] [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: 12/16/2024] [Revised: 01/26/2025] [Indexed: 02/27/2025]
Abstract
Self-propelled lipid-based artificial cells that can achieve controlled rotation and directed translation present significant potential for biomedical applications, yet their engineering poses considerable challenges. Lipid vesicles synthesized via solution-based methods naturally adopt isotropic spherical shapes. Active motion of these spherical objects requires symmetry breaking and rigidity. In this study, giant vesicles are employed as chassis, utilizing enzymes that undergo cyclic, non-reciprocal conformational changes as power sources. Weak, transient protein-protein interactions induce lipid ordering leading to rigidity and spontaneous symmetry breaking. Upon activation of enzyme reactions, these spherical vesicles demonstrate a variety of motion patterns, from pure spinning to 3D spiral trajectories. From experiments and simulations, it is demonstrated how such motion enables the vesicles to cross complex barriers. By utilizing biocompatible and scalable materials, The methodology establishes a solid framework for the design of such self-propelled systems. The work paves the way for advancements in biomedical and environmental technologies such as targeted drug delivery and active matter research.
Collapse
Affiliation(s)
- Veerpal Kaur
- Department of Chemical Sciences, Indian Institute of Science Education and Research Mohali, Punjab, 140306, India
| | | | - Charu Taneja
- Department of Chemical Sciences, Indian Institute of Science Education and Research Mohali, Punjab, 140306, India
| | - Abhishek Chaudhuri
- Department of Physical Sciences, Indian Institute of Science Education and Research Mohali, Punjab, 140306, India
| | - K P Yogendran
- Department of Physical Sciences, Indian Institute of Science Education and Research Mohali, Punjab, 140306, India
| | - Sabyasachi Rakshit
- Department of Chemical Sciences, Indian Institute of Science Education and Research Mohali, Punjab, 140306, India
| |
Collapse
|
4
|
Chung T, Choi YE, Song K, Jung H. How coat proteins shape autophagy in plant cells. PLANT PHYSIOLOGY 2024; 197:kiae426. [PMID: 39259569 DOI: 10.1093/plphys/kiae426] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [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
|
5
|
Sawyer EM, Jensen LE, Meehl JB, Larsen KP, Petito DA, Hurley JH, Voeltz GK. SigmaR1 shapes rough endoplasmic reticulum membrane sheets. Dev Cell 2024; 59:2566-2577.e7. [PMID: 38971154 DOI: 10.1016/j.devcel.2024.06.005] [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: 09/25/2023] [Revised: 02/12/2024] [Accepted: 06/07/2024] [Indexed: 07/08/2024]
Abstract
Rough endoplasmic reticulum (ER) sheets are a fundamental domain of the ER and the gateway into the secretory pathway. Although reticulon proteins stabilize high-curvature ER tubules, it is unclear whether other proteins scaffold the flat membranes of rough ER sheets. Through a proteomics screen using ER sheet-localized RNA-binding proteins as bait, we identify the sigma-1 receptor (SigmaR1) as an ER sheet-shaping factor. High-resolution live cell imaging and electron tomography assign SigmaR1 as an ER sheet-localized factor whose levels determine the amount of rough ER sheets in cells. Structure-guided mutagenesis and in vitro reconstitution on giant unilamellar vesicles further support a mechanism whereby SigmaR1 oligomers use their extended arrays of amphipathic helices to bind and flatten the lumenal leaflet of ER membranes to oppose membrane curvature and stabilize rough ER sheets.
Collapse
Affiliation(s)
- Eric M Sawyer
- Department of Molecular, Cellular, and Developmental Biology, University of Colorado, Boulder, CO 80309, USA; Howard Hughes Medical Institute
| | - Liv E Jensen
- 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
| | - Janet B Meehl
- Department of Molecular, Cellular, and Developmental Biology, University of Colorado, Boulder, CO 80309, USA; Howard Hughes Medical Institute
| | - Kevin P Larsen
- 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
| | - Daniel A Petito
- Department of Molecular, Cellular, and Developmental Biology, University of Colorado, Boulder, CO 80309, USA; Howard Hughes Medical Institute
| | - James H Hurley
- 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
| | - Gia K Voeltz
- Department of Molecular, Cellular, and Developmental Biology, University of Colorado, Boulder, CO 80309, USA; Howard Hughes Medical Institute.
| |
Collapse
|
6
|
Deater M, Lloyd RE. TDRD3 functions as a selective autophagy receptor with dual roles in autophagy and modulation of stress granule stability. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.09.22.614367. [PMID: 39345463 PMCID: PMC11430058 DOI: 10.1101/2024.09.22.614367] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 10/01/2024]
Abstract
Tudor Domain Containing 3 (TDRD3) is a methylarginine-reader protein that functions as a scaffold in the nucleus facilitating transcription, however TDRD3 is also recruited to stress granules (SGs) during the Integrated Stress Response (ISR) although its function therein remains largely unknown. We previously showed that TDRD3 is a novel antiviral restriction factor that is cleaved by virus 2A protease, and plays complex modulatory roles in both interferon and inflammatory signaling during stress and enterovirus infections. Here we have found that TDRD3 contains structural motifs similar to known selective autophagy receptors such as p62/SQSTM1, sharing ubiquitin associated domains (UBA) and LC3 interacting regions (LIR) that anchor cargo destined for autophagosomes to activated LC3 protein coating autophagosome membranes. This is of interest since enteroviruses hijack autophagy machinery to facilitate formation of viral replication factories, virus assembly and egress from the infected cell. Here we explored possible roles of TDRD3 in autophagy, hypothesizing that TDRD3 may function as a specialized selective autophagy receptor. We found that KO of TDRD3 in HeLa cells significantly reduces starvation induced autophagy, while its reintroduction restores it in a dose-dependent manner. Autophagy receptors are degraded during autophagy and expression levels decrease during this time. We found that TDRD3 levels decrease to the same extent as the autophagy receptor p62/SQSTM1 during autophagy, indicating autophagy-targeted turnover in that role. Knockout of TDRD3 or G3BP1 did not make significant changes in overall cell localization of LC3B or p62/SQSTM1, but did result in greater concentration of Lamp2 phagosome marker for phagosomes and phagolysosomes. To test the potential roles of TDRD3 in autophagic processes, we created a series of deletion mutants of TDRD3 lacking either UBA domain or the various LIR motifs that are predicted to interact with LC3B. Microscopic examination of starved cells expressing these variants of TDRD3 showed ΔLIR-TDRD3 had defects in colocalization with LC3B or Lamp2. Further, super resolution microscopy revealed ring structures with TDRD3 interfacing with p62/SQSTM1. In examination of arsenite induced stress granules we found recruitment of TDRD3 variants disrupted normally tight SG condensation, altered the decay rate of SGs upon release from stress and the kinetics of SG formation. We found evidence that the LIR3 motif on TDRD3 is involved in TDRD3 interaction with LC3B in coIP experiments, colocalization studies, and that this motif plays a key role in TDRD3 recruitment to SGs and SG resolution. Overall, these data support a functional role of TDRD3 in selective autophagy in a mode similar to p62/SQSTM1, with specific roles in SG stability and turnover. Enterovirus cleavage of TDRD3 likely affects both antiviral and autophagic responses that the virus controls for replication.
Collapse
Affiliation(s)
- Matthew Deater
- Department of Molecular Virology and Immunology, Baylor College of Medicine, Houston, TX 77030
| | - Richard E Lloyd
- Department of Molecular Virology and Immunology, Baylor College of Medicine, Houston, TX 77030
| |
Collapse
|
7
|
Mohan J, Moparthi SB, Girard-Blanc C, Campisi D, Blanchard S, Nugues C, Rama S, Salles A, Pénard E, Vassilopoulos S, Wollert T. ATG16L1 induces the formation of phagophore-like membrane cups. Nat Struct Mol Biol 2024; 31:1448-1459. [PMID: 38834913 DOI: 10.1038/s41594-024-01300-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Accepted: 03/28/2024] [Indexed: 06/06/2024]
Abstract
The hallmark of non-selective autophagy is the formation of cup-shaped phagophores that capture bulk cytoplasm. The process is accompanied by the conjugation of LC3B to phagophores by an E3 ligase complex comprising ATG12-ATG5 and ATG16L1. Here we combined two complementary reconstitution approaches to reveal the function of LC3B and its ligase complex during phagophore expansion. We found that LC3B forms together with ATG12-ATG5-ATG16L1 a membrane coat that remodels flat membranes into cups that closely resemble phagophores. Mechanistically, we revealed that cup formation strictly depends on a close collaboration between LC3B and ATG16L1. Moreover, only LC3B, but no other member of the ATG8 protein family, promotes cup formation. ATG16L1 truncates that lacked the C-terminal membrane binding domain catalyzed LC3B lipidation but failed to assemble coats, did not promote cup formation and inhibited the biogenesis of non-selective autophagosomes. Our results thus demonstrate that ATG16L1 and LC3B induce and stabilize the characteristic cup-like shape of phagophores.
Collapse
Affiliation(s)
- Jagan Mohan
- Membrane Biochemistry and Transport, Institut Pasteur, Université de Paris, Paris, France
| | - Satish B Moparthi
- Membrane Biochemistry and Transport, Institut Pasteur, Université de Paris, Paris, France
- Sorbonne Université, Institut National de la Santé et de la Recherche Médicale, Association Institut de Myologie, Centre de Recherche en Myologie, Paris, France
| | - Christine Girard-Blanc
- Membrane Biochemistry and Transport, Institut Pasteur, Université de Paris, Paris, France
| | - Daniele Campisi
- Membrane Biochemistry and Transport, Institut Pasteur, Université de Paris, Paris, France
| | - Stéphane Blanchard
- Membrane Biochemistry and Transport, Institut Pasteur, Université de Paris, Paris, France
| | - Charlotte Nugues
- Membrane Biochemistry and Transport, Institut Pasteur, Université de Paris, Paris, France
| | - Sowmya Rama
- Membrane Biochemistry and Transport, Institut Pasteur, Université de Paris, Paris, France
| | - Audrey Salles
- Unit of Technology and Service Photonic BioImaging (UTechS PBI), C2RT, Institut Pasteur, Université de Paris, Paris, France
| | - Esthel Pénard
- Ultrastructural BioImaging Core Facility (UBI), C2RT, Institut Pasteur, Université Paris Cité, Paris, France
| | - Stéphane Vassilopoulos
- Sorbonne Université, Institut National de la Santé et de la Recherche Médicale, Association Institut de Myologie, Centre de Recherche en Myologie, Paris, France.
| | - Thomas Wollert
- Membrane Biochemistry and Transport, Institut Pasteur, Université de Paris, Paris, France.
| |
Collapse
|
8
|
Gubas A, Attridge E, Jefferies HB, Nishimura T, Razi M, Kunzelmann S, Gilad Y, Mercer TJ, Wilson MM, Kimchi A, Tooze SA. WIPI2b recruitment to phagophores and ATG16L1 binding are regulated by ULK1 phosphorylation. EMBO Rep 2024; 25:3789-3811. [PMID: 39152217 PMCID: PMC11387628 DOI: 10.1038/s44319-024-00215-5] [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: 12/15/2023] [Revised: 06/21/2024] [Accepted: 07/04/2024] [Indexed: 08/19/2024] Open
Abstract
One of the key events in autophagy is the formation of a double-membrane phagophore, and many regulatory mechanisms underpinning this remain under investigation. WIPI2b is among the first proteins to be recruited to the phagophore and is essential for stimulating autophagy flux by recruiting the ATG12-ATG5-ATG16L1 complex, driving LC3 and GABARAP lipidation. Here, we set out to investigate how WIPI2b function is regulated by phosphorylation. We studied two phosphorylation sites on WIPI2b, S68 and S284. Phosphorylation at these sites plays distinct roles, regulating WIPI2b's association with ATG16L1 and the phagophore, respectively. We confirm WIPI2b is a novel ULK1 substrate, validated by the detection of endogenous phosphorylation at S284. Notably, S284 is situated within an 18-amino acid stretch, which, when in contact with liposomes, forms an amphipathic helix. Phosphorylation at S284 disrupts the formation of the amphipathic helix, hindering the association of WIPI2b with membranes and autophagosome formation. Understanding these intricacies in the regulatory mechanisms governing WIPI2b's association with its interacting partners and membranes, holds the potential to shed light on these complex processes, integral to phagophore biogenesis.
Collapse
Affiliation(s)
- Andrea Gubas
- Molecular Cell Biology of Autophagy, The Francis Crick Institute, 1 Midland Road, London, NW1 1AT, UK
- Muscular Dystrophy UK, London, SE1 8QD, UK
| | - Eleanor Attridge
- Molecular Cell Biology of Autophagy, The Francis Crick Institute, 1 Midland Road, London, NW1 1AT, UK
| | - Harold Bj Jefferies
- Molecular Cell Biology of Autophagy, The Francis Crick Institute, 1 Midland Road, London, NW1 1AT, UK
| | - Taki Nishimura
- Department of Biochemistry and Molecular Biology, Graduate School and Faculty of Medicine, The University of Tokyo, Tokyo, Japan
- PRESTO, Japan Science and Technology Agency, Chiyoda-ku, Tokyo, Japan
| | - Minoo Razi
- Molecular Cell Biology of Autophagy, The Francis Crick Institute, 1 Midland Road, London, NW1 1AT, UK
| | - Simone Kunzelmann
- Structural Biology Science Technology Platform, The Francis Crick Institute, 1 Midland Road, London, NW1 1AT, UK
| | - Yuval Gilad
- The Weizmann Institute of Science, Rehovot, Israel
| | | | | | - Adi Kimchi
- The Weizmann Institute of Science, Rehovot, Israel
| | - Sharon A Tooze
- Molecular Cell Biology of Autophagy, The Francis Crick Institute, 1 Midland Road, London, NW1 1AT, UK.
| |
Collapse
|
9
|
Adriaenssens E, Schaar S, Cook ASI, Stuke JFM, Sawa-Makarska J, Nguyen TN, Ren X, Schuschnig M, Romanov J, Khuu G, Lazarou M, Hummer G, Hurley JH, Martens S. Reconstitution of BNIP3/NIX-mediated autophagy reveals two pathways and hierarchical flexibility of the initiation machinery. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.08.28.609967. [PMID: 39253418 PMCID: PMC11383309 DOI: 10.1101/2024.08.28.609967] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/11/2024]
Abstract
Selective autophagy is a lysosomal degradation pathway that is critical for maintaining cellular homeostasis by disposing of harmful cellular material. While the mechanisms by which soluble cargo receptors recruit the autophagy machinery are becoming increasingly clear, the principles governing how organelle-localized transmembrane cargo receptors initiate selective autophagy remain poorly understood. Here, we demonstrate that transmembrane cargo receptors can initiate autophagosome biogenesis not only by recruiting the upstream FIP200/ULK1 complex but also via a WIPI-ATG13 complex. This latter pathway is employed by the BNIP3/NIX receptors to trigger mitophagy. Additionally, other transmembrane mitophagy receptors, including FUNDC1 and BCL2L13, exclusively use the FIP200/ULK1 complex, while FKBP8 and the ER-phagy receptor TEX264 are capable of utilizing both pathways to initiate autophagy. Our study defines the molecular rules for initiation by transmembrane cargo receptors, revealing remarkable flexibility in the assembly and activation of the autophagy machinery, with significant implications for therapeutic interventions.
Collapse
|
10
|
Deretic V, Duque T, Trosdal E, Paddar M, Javed R, Akepati P. Membrane atg8ylation in Canonical and Noncanonical Autophagy. J Mol Biol 2024; 436:168532. [PMID: 38479594 PMCID: PMC11260254 DOI: 10.1016/j.jmb.2024.168532] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2024] [Revised: 03/04/2024] [Accepted: 03/07/2024] [Indexed: 04/13/2024]
Abstract
Membrane atg8ylation is a homeostatic process responding to membrane remodeling and stress signals. Membranes are atg8ylated by mammalian ATG8 ubiquitin-like proteins through a ubiquitylation-like cascade. A model has recently been put forward which posits that atg8ylation of membranes is conceptually equivalent to ubiquitylation of proteins. Like ubiquitylation, membrane atg8ylation involves E1, E2 and E3 enzymes. The E3 ligases catalyze the final step of atg8ylation of aminophospholipids in membranes. Until recently, the only known E3 ligase for membrane atg8ylation was ATG16L1 in a noncovalent complex with the ATG12-ATG5 conjugate. ATG16L1 was first identified as a factor in canonical autophagy. During canonical autophagy, the ATG16L1-based E3 ligase complex includes WIPI2, which in turn recognizes phosphatidylinositiol 3-phosphate and directs atg8ylation of autophagic phagophores. As an alternative to WIPIs, binding of ATG16L1 to the proton pump V-ATPase guides atg8ylation of endolysosomal and phagosomal membranes in response to lumenal pH changes. Recently, a new E3 complex containing TECPR1 instead of ATG16L1, has been identified that responds to sphingomyelin's presence on the cytofacial side of perturbed endolysosomal membranes. In present review, we cover the principles of membrane atg8ylation, catalog its various presentations, and provide a perspective on the growing repertoire of E3 ligase complexes directing membrane atg8ylation at diverse locations.
Collapse
Affiliation(s)
- Vojo Deretic
- Autophagy Inflammation and Metabolism Center of Biochemical Research Excellence, University of New Mexico School of Medicine, 915 Camino de Salud, NE, Albuquerque, NM 87131, USA; Department of Molecular Genetics and Microbiology, University of New Mexico School of Medicine, 915 Camino de Salud, NE, Albuquerque, NM 87131, USA.
| | - Thabata Duque
- Autophagy Inflammation and Metabolism Center of Biochemical Research Excellence, University of New Mexico School of Medicine, 915 Camino de Salud, NE, Albuquerque, NM 87131, USA; Department of Molecular Genetics and Microbiology, University of New Mexico School of Medicine, 915 Camino de Salud, NE, Albuquerque, NM 87131, USA
| | - Einar Trosdal
- Autophagy Inflammation and Metabolism Center of Biochemical Research Excellence, University of New Mexico School of Medicine, 915 Camino de Salud, NE, Albuquerque, NM 87131, USA; Department of Molecular Genetics and Microbiology, University of New Mexico School of Medicine, 915 Camino de Salud, NE, Albuquerque, NM 87131, USA
| | - Masroor Paddar
- Autophagy Inflammation and Metabolism Center of Biochemical Research Excellence, University of New Mexico School of Medicine, 915 Camino de Salud, NE, Albuquerque, NM 87131, USA; Department of Molecular Genetics and Microbiology, University of New Mexico School of Medicine, 915 Camino de Salud, NE, Albuquerque, NM 87131, USA
| | - Ruheena Javed
- Autophagy Inflammation and Metabolism Center of Biochemical Research Excellence, University of New Mexico School of Medicine, 915 Camino de Salud, NE, Albuquerque, NM 87131, USA; Department of Molecular Genetics and Microbiology, University of New Mexico School of Medicine, 915 Camino de Salud, NE, Albuquerque, NM 87131, USA
| | - Prithvi Akepati
- Gastroenterology Division, Department of Internal Medicine, University of New Mexico School of Medicine, 915 Camino de Salud, NE, Albuquerque, NM 87131, USA
| |
Collapse
|
11
|
Borges-Araújo L, Pereira GP, Valério M, Souza PCT. Assessing the Martini 3 protein model: A review of its path and potential. BIOCHIMICA ET BIOPHYSICA ACTA. PROTEINS AND PROTEOMICS 2024; 1872:141014. [PMID: 38670324 DOI: 10.1016/j.bbapap.2024.141014] [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: 01/05/2024] [Revised: 03/13/2024] [Accepted: 04/09/2024] [Indexed: 04/28/2024]
Abstract
Coarse-grained (CG) protein models have become indispensable tools for studying many biological protein details, from conformational dynamics to the organization of protein macro-complexes, and even the interaction of proteins with other molecules. The Martini force field is one of the most widely used CG models for bio-molecular simulations, partly because of the enormous success of its protein model. With the recent release of a new and improved version of the Martini force field - Martini 3 - a new iteration of its protein model was also made available. The Martini 3 protein force field is an evolution of its Martini 2 counterpart, aimed at improving many of the shortcomings that had been previously identified. In this mini-review, we first provide a general overview of the model and then focus on the successful advances made in the short time since its release, many of which would not have been possible before. Furthermore, we discuss reported limitations, potential directions for model improvement and comment on what the likely future development and application avenues are.
Collapse
Affiliation(s)
- Luís Borges-Araújo
- Laboratoire de Biologie et Modélisation de la Cellule, CNRS, UMR 5239, Inserm, U1293, Université Claude Bernard Lyon 1, Ecole Normale Supérieure de Lyon, 46 Allée d'Italie, 69364 Lyon, France; Centre Blaise Pascal de Simulation et de Modélisation Numérique, Ecole Normale Supérieure de Lyon, 46 Allée d'Italie, 69364 Lyon, France
| | - Gilberto P Pereira
- Laboratoire de Biologie et Modélisation de la Cellule, CNRS, UMR 5239, Inserm, U1293, Université Claude Bernard Lyon 1, Ecole Normale Supérieure de Lyon, 46 Allée d'Italie, 69364 Lyon, France; Centre Blaise Pascal de Simulation et de Modélisation Numérique, Ecole Normale Supérieure de Lyon, 46 Allée d'Italie, 69364 Lyon, France
| | - Mariana Valério
- Laboratoire de Biologie et Modélisation de la Cellule, CNRS, UMR 5239, Inserm, U1293, Université Claude Bernard Lyon 1, Ecole Normale Supérieure de Lyon, 46 Allée d'Italie, 69364 Lyon, France; Centre Blaise Pascal de Simulation et de Modélisation Numérique, Ecole Normale Supérieure de Lyon, 46 Allée d'Italie, 69364 Lyon, France
| | - Paulo C T Souza
- Laboratoire de Biologie et Modélisation de la Cellule, CNRS, UMR 5239, Inserm, U1293, Université Claude Bernard Lyon 1, Ecole Normale Supérieure de Lyon, 46 Allée d'Italie, 69364 Lyon, France; Centre Blaise Pascal de Simulation et de Modélisation Numérique, Ecole Normale Supérieure de Lyon, 46 Allée d'Italie, 69364 Lyon, France.
| |
Collapse
|
12
|
Fu J, Lin J, Dai Z, Lin B, Zhang J. Hypoxia-associated autophagy flux dysregulation in human cancers. Cancer Lett 2024; 590:216823. [PMID: 38521197 DOI: 10.1016/j.canlet.2024.216823] [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: 02/16/2024] [Revised: 03/09/2024] [Accepted: 03/18/2024] [Indexed: 03/25/2024]
Abstract
A general feature of cancer is hypoxia, determined as low oxygen levels. Low oxygen levels may cause cells to alter in ways that contribute to tumor growth and resistance to treatment. Hypoxia leads to variations in cancer cell metabolism, angiogenesis and metastasis. Furthermore, a hypoxic tumor microenvironment might induce immunosuppression. Moreover, hypoxia has the potential to impact cellular processes, such as autophagy. Autophagy refers to the catabolic process by which damaged organelles and toxic macromolecules are broken down. The abnormal activation of autophagy has been extensively recorded in human tumors and it serves as a regulator of cell growth, spread to other parts of the body, and resistance to treatment. There is a correlation between hypoxia and autophagy in human malignancies. Hypoxia can regulate the activity of AMPK, mTOR, Beclin-1, and ATGs to govern autophagy in human malignancies. Furthermore, HIF-1α, serving as an indicator of low oxygen levels, controls the process of autophagy. Hypoxia-induced autophagy has a crucial role in regulating the growth, spread, and resistance to treatment in human malignancies. Hypoxia-induced regulation of autophagy can impact other mechanisms of cell death, such as apoptosis. Chemoresistance and radioresistance have become significant challenges in recent years. Hypoxia-mediated autophagy plays a crucial role in determining the response to these therapeutic treatments.
Collapse
Affiliation(s)
- Jiding Fu
- Department of Intensive Care Unit, Affiliated Cancer Hospital & Institute of Guangzhou Medical University, Guangzhou, Guangdong, 510095, China
| | - Jie Lin
- Department of Radiation Oncology, Affiliated Cancer Hospital & Institute of Guangzhou Medical University, Guangzhou, Guangdong, 510095, China
| | - Zili Dai
- Department of Radiation Oncology, Affiliated Cancer Hospital & Institute of Guangzhou Medical University, Guangzhou, Guangdong, 510095, China
| | - Baisheng Lin
- Department of Radiation Oncology, Affiliated Cancer Hospital & Institute of Guangzhou Medical University, Guangzhou, Guangdong, 510095, China
| | - Jian Zhang
- Department of Radiation Oncology, Affiliated Cancer Hospital & Institute of Guangzhou Medical University, Guangzhou, Guangdong, 510095, China.
| |
Collapse
|
13
|
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
|
14
|
Ballesteros U, Iriondo MN, Varela YR, Goñi FM, Alonso A, Montes LR, Etxaniz A. The N-terminal region of the ATG8 autophagy protein LC3C is essential for its membrane fusion properties. Int J Biol Macromol 2024; 262:129835. [PMID: 38302024 DOI: 10.1016/j.ijbiomac.2024.129835] [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: 12/08/2023] [Revised: 01/25/2024] [Accepted: 01/27/2024] [Indexed: 02/03/2024]
Abstract
Autophagy is a catabolic process in which a double-membrane organelle, the autophagosome (AP), engulfs cellular components that will be degraded in the lysosomes. ATG8 protein family members participate at various stages of AP formation. The present study compares the capacity to induce lipid-vesicle tethering and fusion of two ATG8 family members, LC3B and LC3C, with model membranes. LC3B is the most thoroughly studied ATG8 protein. It is generally considered as an autophagosomal marker and a canonical representative of the LC3 subfamily. LC3C is less studied, but recent data have reported its implication in various processes, crucial to cellular homeostasis. The results in this paper show that LC3C induces higher levels of tethering and of intervesicular lipid mixing than LC3B. As the N-terminus of LC3C is different from that of the other family members, various mutants of the N-terminal region of both LC3B and LC3C were designed, and their activities compared. It was concluded that the N-terminal region of LC3C was responsible for the enhanced vesicle tethering, membrane perturbation and vesicle-vesicle fusion activities of LC3C as compared to LC3B. The results suggest a specialized function of LC3C in the AP expansion process.
Collapse
Affiliation(s)
- Uxue Ballesteros
- Department of Biochemistry and Instituto Biofisika (CSIC, UPV/EHU), University of the Basque Country, 48940 Leioa, Spain
| | - Marina N Iriondo
- Department of Biochemistry and Instituto Biofisika (CSIC, UPV/EHU), University of the Basque Country, 48940 Leioa, Spain
| | - Yaiza R Varela
- Department of Biochemistry and Instituto Biofisika (CSIC, UPV/EHU), University of the Basque Country, 48940 Leioa, Spain
| | - Félix M Goñi
- Department of Biochemistry and Instituto Biofisika (CSIC, UPV/EHU), University of the Basque Country, 48940 Leioa, Spain
| | - Alicia Alonso
- Department of Biochemistry and Instituto Biofisika (CSIC, UPV/EHU), University of the Basque Country, 48940 Leioa, Spain
| | - L Ruth Montes
- Department of Biochemistry and Instituto Biofisika (CSIC, UPV/EHU), University of the Basque Country, 48940 Leioa, Spain.
| | - Asier Etxaniz
- Department of Biochemistry and Instituto Biofisika (CSIC, UPV/EHU), University of the Basque Country, 48940 Leioa, Spain.
| |
Collapse
|
15
|
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: 11] [Impact Index Per Article: 11.0] [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.
Collapse
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
| |
Collapse
|
16
|
Pezeshkian W, Ipsen JH. Mesoscale simulation of biomembranes with FreeDTS. Nat Commun 2024; 15:548. [PMID: 38228588 PMCID: PMC10792169 DOI: 10.1038/s41467-024-44819-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Accepted: 01/05/2024] [Indexed: 01/18/2024] Open
Abstract
We present FreeDTS software for performing computational research on biomembranes at the mesoscale. In this software, a membrane is represented by a dynamically triangulated surface equipped with vertex-based inclusions to integrate the effects of integral and peripheral membrane proteins. Several algorithms are included in the software to simulate complex membranes at different conditions such as framed membranes with constant tension, vesicles and high-genus membranes with various fixed volumes or constant pressure differences and applying external forces to membrane regions. Furthermore, the software allows the user to turn off the shape evolution of the membrane and focus solely on the organization of proteins. As a result, we can take realistic membrane shapes obtained from, for example, cryo-electron tomography and backmap them into a finer simulation model. In addition to many biomembrane applications, this software brings us a step closer to simulating realistic biomembranes with molecular resolution. Here we provide several interesting showcases of the power of the software but leave a wide range of potential applications for interested users.
Collapse
Affiliation(s)
- Weria Pezeshkian
- Niels Bohr International Academy, Niels Bohr Institute, University of Copenhagen, Blegdamsvej 17, 2100, Copenhagen, Denmark.
| | - John H Ipsen
- MEMPHYS/PhyLife, Department of Physics, Chemistry and Pharmacy (FKF), University of Southern Denmark, Campusvej 55, 5230, Odense M, Denmark
| |
Collapse
|
17
|
Pajtinka P, Vácha R. Amphipathic Helices Can Sense Both Positive and Negative Curvatures of Lipid Membranes. J Phys Chem Lett 2024; 15:175-179. [PMID: 38153203 PMCID: PMC10788957 DOI: 10.1021/acs.jpclett.3c02785] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Revised: 12/09/2023] [Accepted: 12/19/2023] [Indexed: 12/29/2023]
Abstract
Curvature sensing is an essential ability of biomolecules to preferentially localize to membrane regions of a specific curvature. It has been shown that amphipathic helices (AHs), helical peptides with both hydrophilic and hydrophobic regions, could sense a positive membrane curvature. The origin of this AH sensing has been attributed to their ability to exploit lipid-packing defects that are enhanced in regions of positive curvature. In this study, we revisit an alternative framework where AHs act as sensors of local internal stress within the membrane, suggesting the possibility of an AH sensing a negative membrane curvature. Using molecular dynamics simulations, we gradually tuned the hydrophobicity of AHs, thereby adjusting their insertion depth so that the curvature preference of AHs is switched from positive to negative. This study suggests that highly hydrophobic AHs could preferentially localize proteins to regions of a negative membrane curvature.
Collapse
Affiliation(s)
- Peter Pajtinka
- CEITEC
− Central European Institute of Technology, Masaryk University, Kamenice 753/5, 625 00 Brno, Czech Republic
- National
Centre for Biomolecular Research, Faculty of Science, Masaryk University, Kamenice 5, 625 00 Brno, Czech Republic
| | - Robert Vácha
- CEITEC
− Central European Institute of Technology, Masaryk University, Kamenice 753/5, 625 00 Brno, Czech Republic
- National
Centre for Biomolecular Research, Faculty of Science, Masaryk University, Kamenice 5, 625 00 Brno, Czech Republic
- Department
of Condensed Matter Physics, Faculty of Science, Masaryk University, Kotlářská 267/2, 611 37 Brno, Czech
Republic
| |
Collapse
|
18
|
Proikas-Cezanne T, Haas ML, Pastor-Maldonado CJ, Schüssele DS. Human WIPI β-propeller function in autophagy and neurodegeneration. FEBS Lett 2024; 598:127-139. [PMID: 38058212 DOI: 10.1002/1873-3468.14782] [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: 09/21/2023] [Revised: 11/10/2023] [Accepted: 11/10/2023] [Indexed: 12/08/2023]
Abstract
The four human WIPI β-propellers, WIPI1 through WIPI4, belong to the ancient PROPPIN family and fulfill scaffold functions in the control of autophagy. In this context, WIPI β-propellers function as PI3P effectors during autophagosome formation and loss of WIPI function negatively impacts autophagy and contributes to neurodegeneration. Of particular interest are mutations in WDR45, the human gene that encodes WIPI4. Sporadic WDR45 mutations are the cause of a rare human neurodegenerative disease called BPAN, hallmarked by high brain iron accumulation. Here, we discuss the current understanding of the functions of human WIPI β-propellers and address unanswered questions with a particular focus on the role of WIPI4 in autophagy and BPAN.
Collapse
Affiliation(s)
- Tassula Proikas-Cezanne
- Interfaculty Institute of Cell Biology, Department of Biology, Faculty of Science, Eberhard Karls University Tübingen, Germany
| | - Maximilian L Haas
- Interfaculty Institute of Cell Biology, Department of Biology, Faculty of Science, Eberhard Karls University Tübingen, Germany
| | - Carmen J Pastor-Maldonado
- Interfaculty Institute of Cell Biology, Department of Biology, Faculty of Science, Eberhard Karls University Tübingen, Germany
| | - David S Schüssele
- Interfaculty Institute of Cell Biology, Department of Biology, Faculty of Science, Eberhard Karls University Tübingen, Germany
| |
Collapse
|
19
|
Bueno-Arribas M, Cruz-Cuevas C, Navas MA, Escalante R, Vincent O. Coiled-coil-mediated dimerization of Atg16 is required for binding to the PROPPIN Atg21. Open Biol 2023; 13:230192. [PMID: 37989223 PMCID: PMC10688262 DOI: 10.1098/rsob.230192] [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: 06/22/2023] [Accepted: 10/13/2023] [Indexed: 11/23/2023] Open
Abstract
PROPPINs/WIPIs are β-propeller proteins that bind phosphoinositides and contribute to the recruitment of protein complexes involved in membrane remodelling processes such as autophagosome formation and endosomal trafficking. Yeast Atg21 and mammalian WIPI2 interact with Atg16/ATG16L1 to mediate recruitment of the lipidation machinery to the autophagosomal membrane. Here, we used the reverse double two-hybrid method (RD2H) to identify residues in Atg21 and Atg16 critical for protein-protein binding. Although our results are generally consistent with the crystal structure of the Atg21-Atg16 complex reported previously, they also reveal that dimerization of the Atg16 coiled-coil domain is required for Atg21 binding. Furthermore, most of the residues identified in Atg21 are conserved in WIPI2 and we showed that these residues also mediate ATG16L1 binding. Strikingly, these residues occupy the same position in the β-propeller structure as residues in PROPPINs/WIPIs Hsv2 and WIPI4 that mediate Atg2/ATG2A binding, supporting the idea that these proteins use different amino acids at the same position to interact with different autophagic proteins. Finally, our findings demonstrate the effectiveness of the RD2H system to identify critical residues for protein-protein interactions and the utility of this method to generate combinatory mutants with a complete loss of binding capacity.
Collapse
Affiliation(s)
- Miranda Bueno-Arribas
- Instituto de Investigaciones Biomédicas Sols-Morreale CSIC-UAM, Madrid, 28029, Spain
| | - Celia Cruz-Cuevas
- Instituto de Investigaciones Biomédicas Sols-Morreale CSIC-UAM, Madrid, 28029, Spain
| | - María-Angeles Navas
- Departamento de Bioquímica y Biología Molecular, Facultad de Medicina, Universidad Complutense de Madrid, Madrid, Spain
| | - Ricardo Escalante
- Instituto de Investigaciones Biomédicas Sols-Morreale CSIC-UAM, Madrid, 28029, Spain
| | - Olivier Vincent
- Instituto de Investigaciones Biomédicas Sols-Morreale CSIC-UAM, Madrid, 28029, Spain
| |
Collapse
|
20
|
Deretic V. Atg8ylation as a host-protective mechanism against Mycobacterium tuberculosis. FRONTIERS IN TUBERCULOSIS 2023; 1:1275882. [PMID: 37901138 PMCID: PMC10612523 DOI: 10.3389/ftubr.2023.1275882] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/31/2023]
Abstract
Nearly two decades have passed since the first report on autophagy acting as a cell-autonomous defense against Mycobacterium tuberculosis. This helped usher a new area of research within the field of host-pathogen interactions and led to the recognition of autophagy as an immunological mechanism. Interest grew in the fundamental mechanisms of antimicrobial autophagy and in the prophylactic and therapeutic potential for tuberculosis. However, puzzling in vivo data have begun to emerge in murine models of M. tuberculosis infection. The control of infection in mice affirmed the effects of certain autophagy genes, specifically ATG5, but not of other ATGs. Recent studies with a more complete inactivation of ATG genes now show that multiple ATG genes are indeed necessary for protection against M. tuberculosis. These particular ATG genes are involved in the process of membrane atg8ylation. Atg8ylation in mammalian cells is a broad response to membrane stress, damage and remodeling of which canonical autophagy is one of the multiple downstream outputs. The current developments clarify the controversies and open new avenues for both fundamental and translational studies.
Collapse
Affiliation(s)
- Vojo Deretic
- Autophagy, Inflammation and Metabolism Center of Biochemical Research Excellence
- Department of Molecular Genetics and Microbiology, University of New Mexico School of Medicine, 915 Camino de Salud, NE, Albuquerque, NM 87131, USA
| |
Collapse
|
21
|
Sitarska E, Almeida SD, Beckwith MS, Stopp J, Czuchnowski J, Siggel M, Roessner R, Tschanz A, Ejsing C, Schwab Y, Kosinski J, Sixt M, Kreshuk A, Erzberger A, Diz-Muñoz A. Sensing their plasma membrane curvature allows migrating cells to circumvent obstacles. Nat Commun 2023; 14:5644. [PMID: 37704612 PMCID: PMC10499897 DOI: 10.1038/s41467-023-41173-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Accepted: 08/22/2023] [Indexed: 09/15/2023] Open
Abstract
To navigate through diverse tissues, migrating cells must balance persistent self-propelled motion with adaptive behaviors to circumvent obstacles. We identify a curvature-sensing mechanism underlying obstacle evasion in immune-like cells. Specifically, we propose that actin polymerization at the advancing edge of migrating cells is inhibited by the curvature-sensitive BAR domain protein Snx33 in regions with inward plasma membrane curvature. The genetic perturbation of this machinery reduces the cells' capacity to evade obstructions combined with faster and more persistent cell migration in obstacle-free environments. Our results show how cells can read out their surface topography and utilize actin and plasma membrane biophysics to interpret their environment, allowing them to adaptively decide if they should move ahead or turn away. On the basis of our findings, we propose that the natural diversity of BAR domain proteins may allow cells to tune their curvature sensing machinery to match the shape characteristics in their environment.
Collapse
Affiliation(s)
- Ewa Sitarska
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, 69117, Heidelberg, Germany
- Collaboration for joint PhD degree between EMBL and Heidelberg University, Faculty of Biosciences, EMBL and Heidelberg University, Heidelberg, Germany
| | - Silvia Dias Almeida
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, 69117, Heidelberg, Germany
- Division of Medical Image Computing, German Cancer Research Center (DKFZ), 69120, Heidelberg, Germany
| | | | - Julian Stopp
- Institute of Science and Technology Austria, 3400, Klosterneuburg, Austria
| | - Jakub Czuchnowski
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, 69117, Heidelberg, Germany
| | - Marc Siggel
- EMBL Hamburg, European Molecular Biology Laboratory, 22607, Hamburg, Germany
- Centre for Structural Systems Biology, 22607, Hamburg, Germany
| | - Rita Roessner
- EMBL Hamburg, European Molecular Biology Laboratory, 22607, Hamburg, Germany
- Centre for Structural Systems Biology, 22607, Hamburg, Germany
| | - Aline Tschanz
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, 69117, Heidelberg, Germany
- Collaboration for joint PhD degree between EMBL and Heidelberg University, Faculty of Biosciences, EMBL and Heidelberg University, Heidelberg, Germany
| | - Christer Ejsing
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, 69117, Heidelberg, Germany
- Department of Biochemistry and Molecular Biology, Villum Center for Bioanalytical Sciences, University of Southern Denmark, Campusvej 55, 5230, Odense, Denmark
| | - Yannick Schwab
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, 69117, Heidelberg, Germany
| | - Jan Kosinski
- EMBL Hamburg, European Molecular Biology Laboratory, 22607, Hamburg, Germany
- Centre for Structural Systems Biology, 22607, Hamburg, Germany
- Structural and Computational Biology Unit, European Molecular Biology Laboratory, 69117, Heidelberg, Germany
| | - Michael Sixt
- Institute of Science and Technology Austria, 3400, Klosterneuburg, Austria
| | - Anna Kreshuk
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, 69117, Heidelberg, Germany
| | - Anna Erzberger
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, 69117, Heidelberg, Germany
| | - Alba Diz-Muñoz
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, 69117, Heidelberg, Germany.
| |
Collapse
|
22
|
Almansa-Gómez S, Prieto-Ruiz F, Cansado J, Madrid M. Autophagy Modulation as a Potential Therapeutic Strategy in Osteosarcoma: Current Insights and Future Perspectives. Int J Mol Sci 2023; 24:13827. [PMID: 37762129 PMCID: PMC10531374 DOI: 10.3390/ijms241813827] [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: 08/07/2023] [Revised: 09/04/2023] [Accepted: 09/06/2023] [Indexed: 09/29/2023] Open
Abstract
Autophagy, the process that enables the recycling and degradation of cellular components, is essential for homeostasis, which occurs in response to various types of stress. Autophagy plays an important role in the genesis and evolution of osteosarcoma (OS). The conventional treatment of OS has limitations and is not always effective at controlling the disease. Therefore, numerous researchers have analyzed how controlling autophagy could be used as a treatment or strategy to reverse resistance to therapy in OS. They highlight how the inhibition of autophagy improves the efficacy of chemotherapeutic treatments and how the promotion of autophagy could prove positive in OS therapy. The modulation of autophagy can also be directed against OS stem cells, improving treatment efficacy and preventing cancer recurrence. Despite promising findings, future studies are needed to elucidate the molecular mechanisms of autophagy and its relationship to OS, as well as the mechanisms underlying the functioning of autophagic modulators. Careful evaluation is required as autophagy modulation may have adverse effects on normal cells, and the optimization of autophagic modulators for use as drugs in OS is imperative.
Collapse
Affiliation(s)
| | | | - José Cansado
- Yeast Physiology Group, Departamento de Genética y Microbiología, Facultad de Biología, Universidad de Murcia, 30100 Murcia, Spain; (S.A.-G.); (F.P.-R.)
| | - Marisa Madrid
- Yeast Physiology Group, Departamento de Genética y Microbiología, Facultad de Biología, Universidad de Murcia, 30100 Murcia, Spain; (S.A.-G.); (F.P.-R.)
| |
Collapse
|
23
|
Kaur N, de la Ballina LR, Haukaas HS, Torgersen ML, Radulovic M, Munson MJ, Sabirsh A, Stenmark H, Simonsen A, Carlsson SR, Lystad AH. TECPR1 is activated by damage-induced sphingomyelin exposure to mediate noncanonical autophagy. EMBO J 2023; 42:e113105. [PMID: 37409525 PMCID: PMC10476171 DOI: 10.15252/embj.2022113105] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Revised: 05/30/2023] [Accepted: 06/07/2023] [Indexed: 07/07/2023] Open
Abstract
Cells use noncanonical autophagy, also called conjugation of ATG8 to single membranes (CASM), to label damaged intracellular compartments with ubiquitin-like ATG8 family proteins in order to signal danger caused by pathogens or toxic compounds. CASM relies on E3 complexes to sense membrane damage, but so far, only the mechanism to activate ATG16L1-containing E3 complexes, associated with proton gradient loss, has been described. Here, we show that TECPR1-containing E3 complexes are key mediators of CASM in cells treated with a variety of pharmacological drugs, including clinically relevant nanoparticles, transfection reagents, antihistamines, lysosomotropic compounds, and detergents. Interestingly, TECPR1 retains E3 activity when ATG16L1 CASM activity is obstructed by the Salmonella Typhimurium pathogenicity factor SopF. Mechanistically, TECPR1 is recruited by damage-induced sphingomyelin (SM) exposure using two DysF domains, resulting in its activation and ATG8 lipidation. In vitro assays using purified human TECPR1-ATG5-ATG12 complex show direct activation of its E3 activity by SM, whereas SM has no effect on ATG16L1-ATG5-ATG12. We conclude that TECPR1 is a key activator of CASM downstream of SM exposure.
Collapse
Affiliation(s)
- Namrita Kaur
- Centre for Cancer Cell Reprogramming, Faculty of Medicine, University of Oslo, Oslo, Norway
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway
| | - Laura Rodriguez de la Ballina
- Centre for Cancer Cell Reprogramming, Faculty of Medicine, University of Oslo, Oslo, Norway
- Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Håvard Styrkestad Haukaas
- Centre for Cancer Cell Reprogramming, Faculty of Medicine, University of Oslo, Oslo, Norway
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway
| | - Maria Lyngaas Torgersen
- Centre for Cancer Cell Reprogramming, Faculty of Medicine, University of Oslo, Oslo, Norway
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway
| | - Maja Radulovic
- Centre for Cancer Cell Reprogramming, Faculty of Medicine, University of Oslo, Oslo, Norway
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway
| | - Michael J Munson
- Advanced Drug Delivery, Pharmaceutical Sciences, Biopharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Alan Sabirsh
- Advanced Drug Delivery, Pharmaceutical Sciences, Biopharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Harald Stenmark
- Centre for Cancer Cell Reprogramming, Faculty of Medicine, University of Oslo, Oslo, Norway
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway
| | - Anne Simonsen
- Centre for Cancer Cell Reprogramming, Faculty of Medicine, University of Oslo, Oslo, Norway
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway
- Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Sven R Carlsson
- Department of Medical Biochemistry and Biophysics, University of Umeå, Umeå, Sweden
| | - Alf Håkon Lystad
- Centre for Cancer Cell Reprogramming, Faculty of Medicine, University of Oslo, Oslo, Norway
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway
- Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| |
Collapse
|
24
|
Fiorin G, Forrest LR, Faraldo-Gómez JD. Membrane free-energy landscapes derived from atomistic dynamics explain nonuniversal cholesterol-induced stiffening. PNAS NEXUS 2023; 2:pgad269. [PMID: 37637198 PMCID: PMC10456217 DOI: 10.1093/pnasnexus/pgad269] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Revised: 07/31/2023] [Accepted: 08/03/2023] [Indexed: 08/29/2023]
Abstract
All lipid membranes have inherent morphological preferences and resist deformation. Yet adaptations in membrane shape can and do occur at multiple length scales. While this plasticity is crucial for cellular physiology, the factors controlling the morphological energetics of lipid bilayers and the dominant mechanisms of membrane remodeling remain to be fully understood. An ongoing debate regarding the universality of the stiffening effect of cholesterol underscores the challenges facing this field, both experimentally and theoretically, even for simple lipid mixtures. On the computational side, we have argued that enhanced-sampling all-atom molecular dynamics simulations are uniquely suited for the quantification of membrane conformational energetics, as they minimize a priori assumptions and permit analysis of bilayers in deformed states. To showcase this approach, we examine reported inconsistencies between alternative experimental measurements of bending moduli for cholesterol-enriched membranes. Specifically, we analyze lipid bilayers with different chain saturation and compute free-energy landscapes for curvature deformations distributed over areas from ∼5 to ∼60 nm2 . These enhanced simulations, totaling over 100 μs of sampling time, enable us to directly quantify both bending and tilt moduli and to dissect the contributing factors and molecular mechanisms of curvature generation at each length scale. Our results show that the effects of cholesterol on bending rigidity are lipid-specific and suggest that this specificity arises from differences in the torsional dynamics of the acyl chains. In summary, we demonstrate that quantitative relationships can now be established between lipid structure and bending energetics, paving the way for addressing open fundamental questions in cell membrane mechanics.
Collapse
Affiliation(s)
- Giacomo Fiorin
- National Institute for Neurological Disorders and Stroke, Bethesda, MD 20892, USA
- National Heart, Lung and Blood Institute, Bethesda, MD 20894, USA
| | - Lucy R Forrest
- National Institute for Neurological Disorders and Stroke, Bethesda, MD 20892, USA
| | | |
Collapse
|
25
|
Álvarez D, Sapia J, Vanni S. Computational modeling of membrane trafficking processes: From large molecular assemblies to chemical specificity. Curr Opin Cell Biol 2023; 83:102205. [PMID: 37451175 DOI: 10.1016/j.ceb.2023.102205] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Revised: 06/16/2023] [Accepted: 06/16/2023] [Indexed: 07/18/2023]
Abstract
In the last decade, molecular dynamics (MD) simulations have become an essential tool to investigate the molecular properties of membrane trafficking processes, often in conjunction with experimental approaches. The combination of MD simulations with recent developments in structural biology, such as cryo-electron microscopy and artificial intelligence-based structure determination, opens new, exciting possibilities for future investigations. However, the full potential of MD simulations to provide a molecular view of the complex and dynamic processes involving membrane trafficking can only be realized if certain limitations are addressed, and especially those concerning the quality of coarse-grain models, which, despite recent successes in describing large-scale systems, still suffer from far-from-ideal chemical accuracy. In this review, we will highlight recent success stories of MD simulations in the investigation of membrane trafficking processes, their implications for future research, and the challenges that lie ahead in this specific research domain.
Collapse
Affiliation(s)
- Daniel Álvarez
- Department of Biology, University of Fribourg, Switzerland; Departamento de Química Física y Analítica, Universidad de Oviedo, Spain
| | - Jennifer Sapia
- Department of Biology, University of Fribourg, Switzerland
| | - Stefano Vanni
- Department of Biology, University of Fribourg, Switzerland; Université Côte d'Azur, Inserm, CNRS, Institut de Pharmacologie Moléculaire et Cellulaire, Valbonne, France.
| |
Collapse
|
26
|
Rühmkorf A, Harbauer AB. Role of Mitochondria-ER Contact Sites in Mitophagy. Biomolecules 2023; 13:1198. [PMID: 37627263 PMCID: PMC10452924 DOI: 10.3390/biom13081198] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 07/28/2023] [Accepted: 07/29/2023] [Indexed: 08/27/2023] Open
Abstract
Mitochondria are often referred to as the "powerhouse" of the cell. However, this organelle has many more functions than simply satisfying the cells' metabolic needs. Mitochondria are involved in calcium homeostasis and lipid metabolism, and they also regulate apoptotic processes. Many of these functions require contact with the ER, which is mediated by several tether proteins located on the respective organellar surfaces, enabling the formation of mitochondria-ER contact sites (MERCS). Upon damage, mitochondria produce reactive oxygen species (ROS) that can harm the surrounding cell. To circumvent toxicity and to maintain a functional pool of healthy organelles, damaged and excess mitochondria can be targeted for degradation via mitophagy, a form of selective autophagy. Defects in mitochondria-ER tethers and the accumulation of damaged mitochondria are found in several neurodegenerative diseases, including Parkinson's disease and amyotrophic lateral sclerosis, which argues that the interplay between the two organelles is vital for neuronal health. This review provides an overview of the different mechanisms of mitochondrial quality control that are implicated with the different mitochondria-ER tether proteins, and also provides a novel perspective on how MERCS are involved in mediating mitophagy upon mitochondrial damage.
Collapse
Affiliation(s)
- Alina Rühmkorf
- TUM Medical Graduate Center, Technical University of Munich, 81675 Munich, Germany
- Max Planck Institute for Biological Intelligence, 82152 Planegg-Martinsried, Germany
| | - Angelika Bettina Harbauer
- Max Planck Institute for Biological Intelligence, 82152 Planegg-Martinsried, Germany
- Institute of Neuronal Cell Biology, Technical University of Munich, 80802 Munich, Germany
- Munich Cluster for Systems Neurology, 81377 Munich, Germany
| |
Collapse
|
27
|
Nishimura T, Lazzeri G, Mizushima N, Covino R, Tooze SA. Unique amphipathic α helix drives membrane insertion and enzymatic activity of ATG3. SCIENCE ADVANCES 2023; 9:eadh1281. [PMID: 37352354 PMCID: PMC10289646 DOI: 10.1126/sciadv.adh1281] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Accepted: 05/22/2023] [Indexed: 06/25/2023]
Abstract
Autophagosome biogenesis requires a localized perturbation of lipid membrane dynamics and a unique protein-lipid conjugate. Autophagy-related (ATG) proteins catalyze this biogenesis on cellular membranes, but the underlying molecular mechanism remains unclear. Focusing on the final step of the protein-lipid conjugation reaction, the ATG8/LC3 lipidation, we show how the membrane association of the conjugation machinery is organized and fine-tuned at the atomistic level. Amphipathic α helices in ATG3 proteins (AHATG3) have low hydrophobicity and contain less bulky residues. Molecular dynamics simulations reveal that AHATG3 regulates the dynamics and accessibility of the thioester bond of the ATG3~LC3 conjugate to lipids, enabling the covalent lipidation of LC3. Live-cell imaging shows that the transient membrane association of ATG3 with autophagic membranes is governed by the less bulky-hydrophobic feature of AHATG3. The unique properties of AHATG3 facilitate protein-lipid bilayer association, leading to the remodeling of the lipid bilayer required for the formation of autophagosomes.
Collapse
Affiliation(s)
- Taki Nishimura
- PRESTO, Japan Science and Technology Agency, Chiyoda-ku, Tokyo 102-0076, Japan
- Department of Biochemistry and Molecular Biology, Graduate School of Medicine, The University of Tokyo, Tokyo 113-0033, Japan
- Molecular Cell Biology of Autophagy Laboratory, The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | - Gianmarco Lazzeri
- Frankfurt Institute for Advanced Studies, Ruth-Moufang-Straße 1, Frankfurt am Main 60438, Germany
- Goethe University, Frankfurt am Main 60438, Germany
| | - Noboru Mizushima
- Department of Biochemistry and Molecular Biology, Graduate School of Medicine, The University of Tokyo, Tokyo 113-0033, Japan
| | - Roberto Covino
- Frankfurt Institute for Advanced Studies, Ruth-Moufang-Straße 1, Frankfurt am Main 60438, Germany
- Goethe University, Frankfurt am Main 60438, Germany
| | - Sharon A. Tooze
- Molecular Cell Biology of Autophagy Laboratory, The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| |
Collapse
|
28
|
Santovito D, Steffens S, Barachini S, Madonna R. Autophagy, innate immunity, and cardiac disease. Front Cell Dev Biol 2023; 11:1149409. [PMID: 37234771 PMCID: PMC10206260 DOI: 10.3389/fcell.2023.1149409] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2023] [Accepted: 05/02/2023] [Indexed: 05/28/2023] Open
Abstract
Autophagy is an evolutionarily conserved mechanism of cell adaptation to metabolic and environmental stress. It mediates the disposal of protein aggregates and dysfunctional organelles, although non-conventional features have recently emerged to broadly extend the pathophysiological relevance of autophagy. In baseline conditions, basal autophagy critically regulates cardiac homeostasis to preserve structural and functional integrity and protect against cell damage and genomic instability occurring with aging. Moreover, autophagy is stimulated by multiple cardiac injuries and contributes to mechanisms of response and remodeling following ischemia, pressure overload, and metabolic stress. Besides cardiac cells, autophagy orchestrates the maturation of neutrophils and other immune cells, influencing their function. In this review, we will discuss the evidence supporting the role of autophagy in cardiac homeostasis, aging, and cardioimmunological response to cardiac injury. Finally, we highlight possible translational perspectives of modulating autophagy for therapeutic purposes to improve the care of patients with acute and chronic cardiac disease.
Collapse
Affiliation(s)
- Donato Santovito
- Institute for Cardiovascular Prevention (IPEK), Ludwig-Maximilians-University (LMU) Munich, Munich, Germany
- German Center for Cardiovascular Research (DZHK), Partner Site Munich Heart Alliance, Munich, Germany
- Unit of Milan, Institute for Genetic and Biomedical Research (IRGB), National Research Council, Milan, Italy
| | - Sabine Steffens
- Institute for Cardiovascular Prevention (IPEK), Ludwig-Maximilians-University (LMU) Munich, Munich, Germany
- German Center for Cardiovascular Research (DZHK), Partner Site Munich Heart Alliance, Munich, Germany
| | - Serena Barachini
- Hematology Division, Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - Rosalinda Madonna
- Cardiology Division, Cardio-Thoracic and Vascular Department, Azienda Ospedaliero-Universitaria Pisana, Pisa, Italy
- Department of Surgical, Medical, Molecular Pathology & Critical Care Sciences, University of Pisa, Pisa, Italy
| |
Collapse
|
29
|
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
|
30
|
Ball HL, Said H, Chapman K, Fu R, Xiong Y, Burk JA, Rosenbaum D, Veneziano R, Cotten ML. Orexin A, an amphipathic α-helical neuropeptide involved in pleiotropic functions in the nervous and immune systems: Synthetic approach and biophysical studies of the membrane-bound state. Biophys Chem 2023; 297:107007. [PMID: 37037119 DOI: 10.1016/j.bpc.2023.107007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Revised: 03/11/2023] [Accepted: 03/12/2023] [Indexed: 03/16/2023]
Abstract
This research reports on the membrane interactions of orexin A (OXA), an α-helical and amphipathic neuropeptide that contains 33 residues and two disulfide bonds in the N-terminal region. OXA, which activates the orexins 1 and 2 receptors in neural and immune cell membranes, has essential pleiotropic physiological effects, including at the levels of arousal, sleep/wakefulness, energy balance, neuroprotection, lipid signaling, the inflammatory response, and pain. As a result, the orexin system has become a prominent target to treat diseases such as sleep disorders, drug addiction, and inflammation. While the high-resolution structure of OXA has been investigated in water and bound to micelles, there is a lack of information about its conformation bound to phospholipid membranes and its receptors. NMR is a powerful method to investigate peptide structures in a membrane environment. To facilitate the NMR structural studies of OXA exposed to membranes, we present a novel synthetic scheme, leading to the production of isotopically-labeled material at high purity. A receptor activation assay shows that the 15N-labeled peptide is biologically active. Biophysical studies are performed using surface plasmon resonance, circular dichroism, and NMR to investigate the interactions of OXA with phospholipid bilayers. The results demonstrate a strong interaction between the peptide and phospholipids, an increase in α-helical content upon membrane binding, and an in-plane orientation of the C-terminal region critical to function. This new knowledge about structure-activity relationships in OXA could inspire the design of novel therapeutics that leverage the anti-inflammatory and neuro-protective functions of OXA, and therefore could help address neuroinflammation, a major issue associated with neurological disorders such as Alzheimer's disease.
Collapse
Affiliation(s)
- Haydn L Ball
- Department of Chemistry, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Hooda Said
- Department of Bioengineering, College of Engineering and Computing, George Mason University, Fairfax, VA 22030, USA
| | - Karen Chapman
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Riqiang Fu
- National High Magnetic Field Laboratory, Tallahassee, FL 32310, USA
| | - Yawei Xiong
- Department of Applied Science, William & Mary, Williamsburg, VA 23185, USA
| | - Joshua A Burk
- Department of Psychological Sciences, William & Mary, Williamsburg, VA 23185, USA
| | - Daniel Rosenbaum
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Remi Veneziano
- Department of Bioengineering, College of Engineering and Computing, George Mason University, Fairfax, VA 22030, USA
| | - Myriam L Cotten
- Department of Applied Science, William & Mary, Williamsburg, VA 23185, USA.
| |
Collapse
|
31
|
Zhen Y, Stenmark H. Autophagosome Biogenesis. Cells 2023; 12:cells12040668. [PMID: 36831335 PMCID: PMC9954227 DOI: 10.3390/cells12040668] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Revised: 02/10/2023] [Accepted: 02/16/2023] [Indexed: 02/22/2023] Open
Abstract
Autophagy-the lysosomal degradation of cytoplasm-plays a central role in cellular homeostasis and protects cells from potentially harmful agents that may accumulate in the cytoplasm, including pathogens, protein aggregates, and dysfunctional organelles. This process is initiated by the formation of a phagophore membrane, which wraps around a portion of cytoplasm or cargo and closes to form a double-membrane autophagosome. Upon the fusion of the autophagosome with a lysosome, the sequestered material is degraded by lysosomal hydrolases in the resulting autolysosome. Several alternative membrane sources of autophagosomes have been proposed, including the plasma membrane, endosomes, mitochondria, endoplasmic reticulum, lipid droplets, hybrid organelles, and de novo synthesis. Here, we review recent progress in our understanding of how the autophagosome is formed and highlight the proposed role of vesicles that contain the lipid scramblase ATG9 as potential seeds for phagophore biogenesis. We also discuss how the phagophore is sealed by the action of the endosomal sorting complex required for transport (ESCRT) proteins.
Collapse
Affiliation(s)
- Yan Zhen
- Centre for Cancer Cell Reprogramming, Faculty of Medicine, University of Oslo, Montebello, N-0379 Oslo, Norway
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Montebello, N-0379 Oslo, Norway
- Correspondence: (Y.Z.); (H.S.); Tel.: +47-22781911 (Y.Z.); +47-22781818 (H.S.)
| | - Harald Stenmark
- Centre for Cancer Cell Reprogramming, Faculty of Medicine, University of Oslo, Montebello, N-0379 Oslo, Norway
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Montebello, N-0379 Oslo, Norway
- Correspondence: (Y.Z.); (H.S.); Tel.: +47-22781911 (Y.Z.); +47-22781818 (H.S.)
| |
Collapse
|
32
|
Fiorin G, Forrest LR, Faraldo-Gómez JD. Membrane free-energy landscapes derived from atomistic dynamics explain nonuniversal cholesterol-induced stiffening. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.02.02.525347. [PMID: 36778237 PMCID: PMC9915699 DOI: 10.1101/2023.02.02.525347] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
All lipid membranes have inherent morphological preferences and resist deformation. Yet adaptations in membrane shape can and do occur at multiple length scales. While this plasticity is crucial for cellular physiology, the factors controlling the morphological energetics of lipid bilayers and the dominant mechanisms of membrane remodeling remain unclear. An ongoing debate regarding the universality of the stiffening effect of cholesterol underscores the challenges facing this field, both experimentally and theoretically, even for simple lipid mixtures. On the computational side, we have argued that enhanced- sampling all-atom molecular dynamics simulations are uniquely suited for quantification of membrane conformational energetics, not only because they minimize a-priori assumptions, but also because they permit analysis of bilayers in deformed states. To showcase this approach, we examine reported inconsistencies between alternative experimental measurements of bending moduli for cholesterol-enriched membranes. Specifically, we analyze lipid bilayers with different chain saturation, and compute free-energy landscapes for curvature deformations distributed over areas from ∼5 to ∼60 nm 2 . These enhanced simulations, totaling over 100 microseconds of sampling time, enable us to directly quantify both bending and tilt moduli, and to dissect the contributing factors and molecular mechanisms of curvature generation at each length scale. Our results show that cholesterol effects are lipid-specific, in agreement with giantvesicle measurements, and explain why experiments probing nanometer scale lipid dynamics diverge. In summary, we demonstrate that quantitative structure-mechanics relationships can now be established for heterogenous membranes, paving the way for addressing open fundamental questions in cell membrane mechanics. Significance Elucidating the energetics and mechanisms of membrane remodeling is an essential step towards understanding cell physiology. This problem is challenging, however, because membrane bending involves both large-scale and atomic-level dynamics, which are difficult to measure simultaneously. A recent controversy regarding the stiffening effect of cholesterol, which is ubiquitous in animal cells, illustrates this challenge. We show how enhanced molecular-dynamics simulations can bridge this length-scale gap and reconcile seemingly incongruent observations. This approach facilitates a conceptual connection between lipid chemistry and membrane mechanics, thereby providing a solid basis for future research on remodeling phenomena, such as in membrane trafficking or viral infection.
Collapse
Affiliation(s)
- Giacomo Fiorin
- National Institute for Neurological Disorders and Stroke, Bethesda, MD, USA
- National Heart, Lung and Blood Institute, Bethesda, MD, USA
| | - Lucy R Forrest
- National Institute for Neurological Disorders and Stroke, Bethesda, MD, USA
| | | |
Collapse
|