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Zens B, Fäßler F, Hansen JM, Hauschild R, Datler J, Hodirnau VV, Zheden V, Alanko J, Sixt M, Schur FK. Lift-out cryo-FIBSEM and cryo-ET reveal the ultrastructural landscape of extracellular matrix. J Cell Biol 2024; 223:e202309125. [PMID: 38506714 PMCID: PMC10955043 DOI: 10.1083/jcb.202309125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Revised: 02/19/2024] [Accepted: 03/01/2024] [Indexed: 03/21/2024] Open
Abstract
The extracellular matrix (ECM) serves as a scaffold for cells and plays an essential role in regulating numerous cellular processes, including cell migration and proliferation. Due to limitations in specimen preparation for conventional room-temperature electron microscopy, we lack structural knowledge on how ECM components are secreted, remodeled, and interact with surrounding cells. We have developed a 3D-ECM platform compatible with sample thinning by cryo-focused ion beam milling, the lift-out extraction procedure, and cryo-electron tomography. Our workflow implements cell-derived matrices (CDMs) grown on EM grids, resulting in a versatile tool closely mimicking ECM environments. This allows us to visualize ECM for the first time in its hydrated, native context. Our data reveal an intricate network of extracellular fibers, their positioning relative to matrix-secreting cells, and previously unresolved structural entities. Our workflow and results add to the structural atlas of the ECM, providing novel insights into its secretion and assembly.
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Affiliation(s)
- Bettina Zens
- Institute of Science and Technology Austria (ISTA), Klosterneuburg, Austria
| | - Florian Fäßler
- Institute of Science and Technology Austria (ISTA), Klosterneuburg, Austria
| | - Jesse M. Hansen
- Institute of Science and Technology Austria (ISTA), Klosterneuburg, Austria
| | - Robert Hauschild
- Institute of Science and Technology Austria (ISTA), Klosterneuburg, Austria
| | - Julia Datler
- Institute of Science and Technology Austria (ISTA), Klosterneuburg, Austria
| | | | - Vanessa Zheden
- Institute of Science and Technology Austria (ISTA), Klosterneuburg, Austria
| | - Jonna Alanko
- Institute of Science and Technology Austria (ISTA), Klosterneuburg, Austria
| | - Michael Sixt
- Institute of Science and Technology Austria (ISTA), Klosterneuburg, Austria
| | - Florian K.M. Schur
- Institute of Science and Technology Austria (ISTA), Klosterneuburg, Austria
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2
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Fäßler F, Zens B, Hauschild R, Schur FKM. 3D printed cell culture grid holders for improved cellular specimen preparation in cryo-electron microscopy. J Struct Biol 2020; 212:107633. [PMID: 32987119 DOI: 10.1016/j.jsb.2020.107633] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Revised: 09/11/2020] [Accepted: 09/22/2020] [Indexed: 12/16/2022]
Abstract
Cryo-electron microscopy (cryo-EM) of cellular specimens provides insights into biological processes and structures within a native context. However, a major challenge still lies in the efficient and reproducible preparation of adherent cells for subsequent cryo-EM analysis. This is due to the sensitivity of many cellular specimens to the varying seeding and culturing conditions required for EM experiments, the often limited amount of cellular material and also the fragility of EM grids and their substrate. Here, we present low-cost and reusable 3D printed grid holders, designed to improve specimen preparation when culturing challenging cellular samples directly on grids. The described grid holders increase cell culture reproducibility and throughput, and reduce the resources required for cell culturing. We show that grid holders can be integrated into various cryo-EM workflows, including micro-patterning approaches to control cell seeding on grids, and for generating samples for cryo-focused ion beam milling and cryo-electron tomography experiments. Their adaptable design allows for the generation of specialized grid holders customized to a large variety of applications.
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Affiliation(s)
- Florian Fäßler
- Institute of Science and Technology Austria, Am Campus 1, Klosterneuburg, Austria
| | - Bettina Zens
- Institute of Science and Technology Austria, Am Campus 1, Klosterneuburg, Austria
| | - Robert Hauschild
- Institute of Science and Technology Austria, Am Campus 1, Klosterneuburg, Austria
| | - Florian K M Schur
- Institute of Science and Technology Austria, Am Campus 1, Klosterneuburg, Austria.
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3
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Sánchez-Wandelmer J, Kriegenburg F, Rohringer S, Schuschnig M, Gómez-Sánchez R, Zens B, Abreu S, Hardenberg R, Hollenstein D, Gao J, Ungermann C, Martens S, Kraft C, Reggiori F. Atg4 proteolytic activity can be inhibited by Atg1 phosphorylation. Nat Commun 2017; 8:295. [PMID: 28821724 PMCID: PMC5562703 DOI: 10.1038/s41467-017-00302-3] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Accepted: 06/19/2017] [Indexed: 11/09/2022] Open
Abstract
The biogenesis of autophagosomes depends on the conjugation of Atg8-like proteins with phosphatidylethanolamine. Atg8 processing by the cysteine protease Atg4 is required for its covalent linkage to phosphatidylethanolamine, but it is also necessary for Atg8 deconjugation from this lipid to release it from membranes. How these two cleavage steps are coordinated is unknown. Here we show that phosphorylation by Atg1 inhibits Atg4 function, an event that appears to exclusively occur at the site of autophagosome biogenesis. These results are consistent with a model where the Atg8-phosphatidylethanolamine pool essential for autophagosome formation is protected at least in part by Atg4 phosphorylation by Atg1 while newly synthesized cytoplasmic Atg8 remains susceptible to constitutive Atg4 processing.The protease Atg4 mediates Atg8 lipidation, required for autophagosome biogenesis, but also triggers Atg8 release from the membranes, however is unclear how these steps are coordinated. Here the authors show that phosphorylation by Atg1 inhibits Atg4 at autophagosome formation sites.
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Affiliation(s)
- Jana Sánchez-Wandelmer
- Department of Cell Biology, University of Groningen, University Medical Center Groningen, A. Deusinglaan 1, 9713 AV, Groningen, The Netherlands.,Department of Cell Biology, University Medical Center Utrecht, Heidelberglaan 100, 8564 CX, Utrecht, The Netherlands
| | - Franziska Kriegenburg
- Department of Cell Biology, University of Groningen, University Medical Center Groningen, A. Deusinglaan 1, 9713 AV, Groningen, The Netherlands.,Department of Cell Biology, University Medical Center Utrecht, Heidelberglaan 100, 8564 CX, Utrecht, The Netherlands
| | - Sabrina Rohringer
- Max F. Perutz Laboratories, University of Vienna, 1030, Vienna, Austria
| | | | - Rubén Gómez-Sánchez
- Department of Cell Biology, University of Groningen, University Medical Center Groningen, A. Deusinglaan 1, 9713 AV, Groningen, The Netherlands.,Department of Cell Biology, University Medical Center Utrecht, Heidelberglaan 100, 8564 CX, Utrecht, The Netherlands
| | - Bettina Zens
- Max F. Perutz Laboratories, University of Vienna, 1030, Vienna, Austria
| | - Susana Abreu
- Department of Cell Biology, University of Groningen, University Medical Center Groningen, A. Deusinglaan 1, 9713 AV, Groningen, The Netherlands.,Department of Cell Biology, University Medical Center Utrecht, Heidelberglaan 100, 8564 CX, Utrecht, The Netherlands
| | - Ralph Hardenberg
- Department of Cell Biology, University of Groningen, University Medical Center Groningen, A. Deusinglaan 1, 9713 AV, Groningen, The Netherlands
| | - David Hollenstein
- Max F. Perutz Laboratories, University of Vienna, 1030, Vienna, Austria
| | - Jieqiong Gao
- University of Osnabrück, Department of Biology/Chemistry, Biochemistry section, Barbarastrasse 13, 49076, Osnabrück, Germany
| | - Christian Ungermann
- University of Osnabrück, Department of Biology/Chemistry, Biochemistry section, Barbarastrasse 13, 49076, Osnabrück, Germany
| | - Sascha Martens
- Max F. Perutz Laboratories, University of Vienna, 1030, Vienna, Austria
| | - Claudine Kraft
- Max F. Perutz Laboratories, University of Vienna, 1030, Vienna, Austria
| | - Fulvio Reggiori
- Department of Cell Biology, University of Groningen, University Medical Center Groningen, A. Deusinglaan 1, 9713 AV, Groningen, The Netherlands. .,Department of Cell Biology, University Medical Center Utrecht, Heidelberglaan 100, 8564 CX, Utrecht, The Netherlands.
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4
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Abreu S, Kriegenburg F, Gómez-Sánchez R, Mari M, Sánchez-Wandelmer J, Skytte Rasmussen M, Soares Guimarães R, Zens B, Schuschnig M, Hardenberg R, Peter M, Johansen T, Kraft C, Martens S, Reggiori F. Conserved Atg8 recognition sites mediate Atg4 association with autophagosomal membranes and Atg8 deconjugation. EMBO Rep 2017; 18:765-780. [PMID: 28330855 DOI: 10.15252/embr.201643146] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Revised: 02/12/2017] [Accepted: 02/20/2017] [Indexed: 12/12/2022] Open
Abstract
Deconjugation of the Atg8/LC3 protein family members from phosphatidylethanolamine (PE) by Atg4 proteases is essential for autophagy progression, but how this event is regulated remains to be understood. Here, we show that yeast Atg4 is recruited onto autophagosomal membranes by direct binding to Atg8 via two evolutionarily conserved Atg8 recognition sites, a classical LC3-interacting region (LIR) at the C-terminus of the protein and a novel motif at the N-terminus. Although both sites are important for Atg4-Atg8 interaction in vivo, only the new N-terminal motif, close to the catalytic center, plays a key role in Atg4 recruitment to autophagosomal membranes and specific Atg8 deconjugation. We thus propose a model where Atg4 activity on autophagosomal membranes depends on the cooperative action of at least two sites within Atg4, in which one functions as a constitutive Atg8 binding module, while the other has a preference toward PE-bound Atg8.
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Affiliation(s)
- Susana Abreu
- Department of Cell Biology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.,Department of Cell Biology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Franziska Kriegenburg
- Department of Cell Biology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.,Department of Cell Biology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Rubén Gómez-Sánchez
- Department of Cell Biology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.,Department of Cell Biology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Muriel Mari
- Department of Cell Biology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.,Department of Cell Biology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Jana Sánchez-Wandelmer
- Department of Cell Biology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.,Department of Cell Biology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Mads Skytte Rasmussen
- Molecular Cancer Research Group, Institute of Medical Biology, University of Tromsø - The Arctic University of Norway, Tromsø, Norway
| | - Rodrigo Soares Guimarães
- Department of Cell Biology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.,Department of Cell Biology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Bettina Zens
- Department of Biochemistry and Cell Biology, Max F. Perutz Laboratories (MFPL), Vienna Biocenter (VBC), University of Vienna, Vienna, Austria
| | - Martina Schuschnig
- Department of Biochemistry and Cell Biology, Max F. Perutz Laboratories (MFPL), Vienna Biocenter (VBC), University of Vienna, Vienna, Austria
| | - Ralph Hardenberg
- Department of Cell Biology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Matthias Peter
- Department of Biology, Institute of Biochemistry, Swiss Federal Institute of Technology, Zurich, Switzerland
| | - Terje Johansen
- Molecular Cancer Research Group, Institute of Medical Biology, University of Tromsø - The Arctic University of Norway, Tromsø, Norway
| | - Claudine Kraft
- Department of Biochemistry and Cell Biology, Max F. Perutz Laboratories (MFPL), Vienna Biocenter (VBC), University of Vienna, Vienna, Austria
| | - Sascha Martens
- Department of Biochemistry and Cell Biology, Max F. Perutz Laboratories (MFPL), Vienna Biocenter (VBC), University of Vienna, Vienna, Austria
| | - Fulvio Reggiori
- Department of Cell Biology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands .,Department of Cell Biology, University Medical Center Utrecht, Utrecht, The Netherlands
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5
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Fracchiolla D, Sawa-Makarska J, Zens B, Ruiter AD, Zaffagnini G, Brezovich A, Romanov J, Runggatscher K, Kraft C, Zagrovic B, Martens S. Mechanism of cargo-directed Atg8 conjugation during selective autophagy. eLife 2016; 5. [PMID: 27879200 PMCID: PMC5148612 DOI: 10.7554/elife.18544] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Accepted: 11/21/2016] [Indexed: 12/21/2022] Open
Abstract
Selective autophagy is mediated by cargo receptors that link the cargo to the isolation membrane via interactions with Atg8 proteins. Atg8 proteins are localized to the membrane in an ubiquitin-like conjugation reaction, but how this conjugation is coupled to the presence of the cargo is unclear. Here we show that the S. cerevisiae Atg19, Atg34 and the human p62, Optineurin and NDP52 cargo receptors interact with the E3-like enzyme Atg12~Atg5-Atg16, which stimulates Atg8 conjugation. The interaction of Atg19 with the Atg12~Atg5-Atg16 complex is mediated by its Atg8-interacting motifs (AIMs). We identify the AIM-binding sites in the Atg5 subunit and mutation of these sites impairs selective autophagy. In a reconstituted system the recruitment of the E3 to the prApe1 cargo is sufficient to drive accumulation of conjugated Atg8 at the cargo. The interaction of the Atg12~Atg5-Atg16 complex and Atg8 with Atg19 is mutually exclusive, which may confer directionality to the system. DOI:http://dx.doi.org/10.7554/eLife.18544.001 A living cell must remove unhealthy or excess material from its interior in order to remain healthy and operational. Cells pack this waste into membrane-bound compartments named autophagosomes in a process called autophagy. So-called autophagy proteins make sure that only the unwanted material is eliminated. However, it was not completely clear how these proteins achieve this. What was known was that proteins called cargo receptors recognize and bind to specific waste materials. At the same time, so-called autophagy enzymes tag the membranes of the autophagosome with a protein known as Atg8, so that cargo receptor molecules can bind this membrane. Now, Fracchiolla, Sawa-Makarska et al. report that, in yeast, an autophagy enzyme links these two events by binding to the cargo receptor and promoting the tagging of the autophagosome’s membrane at the same place. The enzyme in question is a complex made from three autophagy proteins (called Atg12, Atg5 and Atg16), and its activity ensures that the membrane is tagged only next to those materials that need to be disposed of. Although it is now clearer how a cell’s waste ends up in the autophagosome, it is still puzzling how this process is regulated and how the other autophagy-related components contribute to this highly coordinated process. In particular, an important next step will be to find out what is the source of membrane that gives rise to the autophagosome. DOI:http://dx.doi.org/10.7554/eLife.18544.002
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Affiliation(s)
- Dorotea Fracchiolla
- Department of Biochemistry and Cell Biology, Max F. Perutz Laboratories (MFPL), University of Vienna, Vienna Biocenter (VBC), Vienna, Austria
| | - Justyna Sawa-Makarska
- Department of Biochemistry and Cell Biology, Max F. Perutz Laboratories (MFPL), University of Vienna, Vienna Biocenter (VBC), Vienna, Austria
| | - Bettina Zens
- Department of Biochemistry and Cell Biology, Max F. Perutz Laboratories (MFPL), University of Vienna, Vienna Biocenter (VBC), Vienna, Austria
| | - Anita de Ruiter
- Department of Structural and Computational Biology, Max F. Perutz Laboratories (MFPL), University of Vienna, Vienna Biocenter (VBC), Vienna, Austria
| | - Gabriele Zaffagnini
- Department of Biochemistry and Cell Biology, Max F. Perutz Laboratories (MFPL), University of Vienna, Vienna Biocenter (VBC), Vienna, Austria
| | - Andrea Brezovich
- Department of Biochemistry and Cell Biology, Max F. Perutz Laboratories (MFPL), University of Vienna, Vienna Biocenter (VBC), Vienna, Austria
| | - Julia Romanov
- Department of Biochemistry and Cell Biology, Max F. Perutz Laboratories (MFPL), University of Vienna, Vienna Biocenter (VBC), Vienna, Austria
| | - Kathrin Runggatscher
- Department of Biochemistry and Cell Biology, Max F. Perutz Laboratories (MFPL), University of Vienna, Vienna Biocenter (VBC), Vienna, Austria
| | - Claudine Kraft
- Department of Biochemistry and Cell Biology, Max F. Perutz Laboratories (MFPL), University of Vienna, Vienna Biocenter (VBC), Vienna, Austria
| | - Bojan Zagrovic
- Department of Structural and Computational Biology, Max F. Perutz Laboratories (MFPL), University of Vienna, Vienna Biocenter (VBC), Vienna, Austria
| | - Sascha Martens
- Department of Biochemistry and Cell Biology, Max F. Perutz Laboratories (MFPL), University of Vienna, Vienna Biocenter (VBC), Vienna, Austria
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6
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Abstract
Macroautophagy, hereafter autophagy, is a major degradation pathway in eukaryotic systems that allows the removal of large intracellular structures such as entire organelles or protein aggregates, thus contributing to the homeostasis of cells and tissues. Autophagy entails the de novo formation of an organelle termed autophagosome, where a cup-shaped structure called isolation membrane nucleates in proximity of a cytoplasmic cargo material. Upon elongation and closure of isolation membranes, the mature autophagosome delivers the sequestered cargo into the lysosomal system for degradation. Among the factors for autophagosome formation are the autophagy-related (Atg) proteins belonging to the Atg8 conjugation system. In this system, the ubiquitin-like Atg8 protein is conjugated to the membrane lipid phosphatidylethanolamine present in autophagosomal membranes. Atg8 can also be removed from membranes by Atg4-mediated deconjugation. Here, we describe in vitro systems that recapitulate the enzymatic reactions occurring in vivo by presenting expression and purification strategies for all the components of the Saccharomyces cerevisiae Atg8 conjugation system. We also present protocols for in vitro Atg8 conjugation and deconjugation reactions employing small and giant unilamellar vesicles.
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Affiliation(s)
- D Fracchiolla
- Max F. Perutz Laboratories, University of Vienna, Vienna Biocenter, Vienna, Austria
| | - B Zens
- Max F. Perutz Laboratories, University of Vienna, Vienna Biocenter, Vienna, Austria
| | - S Martens
- Max F. Perutz Laboratories, University of Vienna, Vienna Biocenter, Vienna, Austria.
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7
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Mossner M, Jann J, Wittig J, Nolte F, Fey S, Nowak V, Obländer J, Pressler J, Müdder K, Klein C, Zens B, Platzbecker U, Schönefeldt C, Fabarius A, Blum H, Schulze T, Haferlach C, Trumpp A, Hofmann W, Medyouf H, Nowak D. 65 MYELODYSPLASTIC SYNDROMES ARE CHARACTERIZED BY RECURRENT PATTERNS IN PATIENT-INDIVIDUAL MUTATIONAL HIERARCHIES THAT ARE SUBJECT TO HIGHLY DYNAMIC SUBCLONAL EVOLUTION DURING THERAPY AND DISEASE PROGRESSION. Leuk Res 2015. [DOI: 10.1016/s0145-2126(15)30066-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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8
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Abstract
Atg8 lipidation can be efficiently reconstituted in vitro. Lipidation and de-lipidation of Atg8 by Atg4 can be analyzed. Reconstitution of Atg8-lipidation using giant unilamellar vesicles offers spatial insights. These assays allow determining the effect of modifications on Atg8 lipidation/de-lipidation.
Macroautophagy is a major bulk degradation pathway for cytoplasmic material in eukaryotic cells. During macroautophagy, double membrane-bound organelles called autophagosomes are formed in a de novo manner. In the course of their formation autophagosomes capture cytoplasmic material, which is subsequently degraded upon fusion with the lysosomal system in complex eukaryotes or the vacuole in yeast. Several proteins are required for autophagosome formation. Among these are the components of two ubiquitin-like conjugation reactions that collectively mediate the conjugation of the ubiquitin-like Atg12 to the Atg5 protein and of the ubiquitin-like protein Atg8 to the headgroup of the membrane lipid phosphatidylethanolamine. The lipidated form of Atg8 is membrane-bound and marks the growing autophagosomal membrane as well as the completed autophagosome. Here we describe assays for the in vitro reconstitution of the Atg8 lipidation reaction using recombinantly expressed and purified proteins derived from Saccharomycescerevisiae in combination with small and giant unilamellar vesicles. The assays enable the study of the biochemical mechanisms of action of the Atg8 lipidation machinery and to analyze the impact of mutations and post-translational modifications of the conjugation machinery on Atg8 lipidation.
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Affiliation(s)
- Bettina Zens
- Max F. Perutz Laboratories, University of Vienna, Dr. Bohr-Gasse 9/3, 1030 Vienna, Austria
| | - Justyna Sawa-Makarska
- Max F. Perutz Laboratories, University of Vienna, Dr. Bohr-Gasse 9/3, 1030 Vienna, Austria
| | - Sascha Martens
- Max F. Perutz Laboratories, University of Vienna, Dr. Bohr-Gasse 9/3, 1030 Vienna, Austria.
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9
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Sawa-Makarska J, Abert C, Romanov J, Zens B, Ibiricu I, Martens S. Cargo binding to Atg19 unmasks additional Atg8 binding sites to mediate membrane-cargo apposition during selective autophagy. Nat Cell Biol 2014; 16:425-433. [PMID: 24705553 PMCID: PMC4009068 DOI: 10.1038/ncb2935] [Citation(s) in RCA: 86] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2013] [Accepted: 02/14/2014] [Indexed: 01/01/2023]
Abstract
Autophagy protects cells from harmful substances such as protein aggregates, damaged mitochondria and intracellular pathogens and has been implicated in a variety of diseases. Selectivity of autophagic processes is mediated by cargo receptors that link cargo to Atg8 family proteins on the developing autophagosomal membrane. To avoid collateral degradation during constitutive autophagic pathways the autophagic machinery must not only select cargo but also exclude non-cargo material. Here we show that cargo directly activates the cargo receptor Atg19 by exposing multiple Atg8 binding sites. Furthermore, Atg19 mediates tight apposition of the cargo and Atg8-coated membranes in a fully reconstituted system. These properties are essential for the function of Atg19 during selective autophagy in vivo. Our results suggest that cargo receptors contribute to tight membrane bending of the isolation membrane around the cargo.
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Affiliation(s)
- Justyna Sawa-Makarska
- Max F. Perutz Laboratories, University of Vienna, Vienna Biocenter, Dr. Bohr-Gasse 9/3, 1030 Vienna, Austria
| | - Christine Abert
- Max F. Perutz Laboratories, University of Vienna, Vienna Biocenter, Dr. Bohr-Gasse 9/3, 1030 Vienna, Austria
| | - Julia Romanov
- Max F. Perutz Laboratories, University of Vienna, Vienna Biocenter, Dr. Bohr-Gasse 9/3, 1030 Vienna, Austria
| | - Bettina Zens
- Max F. Perutz Laboratories, University of Vienna, Vienna Biocenter, Dr. Bohr-Gasse 9/3, 1030 Vienna, Austria
| | - Iosune Ibiricu
- Max F. Perutz Laboratories, University of Vienna, Vienna Biocenter, Dr. Bohr-Gasse 9/3, 1030 Vienna, Austria
| | - Sascha Martens
- Max F. Perutz Laboratories, University of Vienna, Vienna Biocenter, Dr. Bohr-Gasse 9/3, 1030 Vienna, Austria
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10
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Medyouf H, Mossner M, Jann JC, Nolte F, Raffel S, Herrmann C, Lier A, Eisen C, Nowak V, Zens B, Müdder K, Klein C, Obländer J, Fey S, Vogler J, Fabarius A, Riedl E, Roehl H, Kohlmann A, Staller M, Haferlach C, Müller N, John T, Platzbecker U, Metzgeroth G, Hofmann WK, Trumpp A, Nowak D. Myelodysplastic cells in patients reprogram mesenchymal stromal cells to establish a transplantable stem cell niche disease unit. Cell Stem Cell 2014; 14:824-37. [PMID: 24704494 DOI: 10.1016/j.stem.2014.02.014] [Citation(s) in RCA: 292] [Impact Index Per Article: 29.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2013] [Revised: 12/23/2013] [Accepted: 02/26/2014] [Indexed: 01/16/2023]
Abstract
Myelodysplastic syndromes (MDSs) are a heterogeneous group of myeloid neoplasms with defects in hematopoietic stem and progenitor cells (HSPCs) and possibly the HSPC niche. Here, we show that patient-derived mesenchymal stromal cells (MDS MSCs) display a disturbed differentiation program and are essential for the propagation of MDS-initiating Lin(-)CD34(+)CD38(-) stem cells in orthotopic xenografts. Overproduction of niche factors such as CDH2 (N-Cadherin), IGFBP2, VEGFA, and LIF is associated with the ability of MDS MSCs to enhance MDS expansion. These factors represent putative therapeutic targets in order to disrupt critical hematopoietic-stromal interactions in MDS. Finally, healthy MSCs adopt MDS MSC-like molecular features when exposed to hematopoietic MDS cells, indicative of an instructive remodeling of the microenvironment. Therefore, this patient-derived xenograft model provides functional and molecular evidence that MDS is a complex disease that involves both the hematopoietic and stromal compartments. The resulting deregulated expression of niche factors may well also be a feature of other hematopoietic malignancies.
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Affiliation(s)
- Hind Medyouf
- Division of Stem Cells and Cancer, Deutsches Krebsforschungszentrum (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany; German Cancer Consortium, 69120 Heidelberg, Germany.
| | - Maximilian Mossner
- Department of Hematology and Oncology, University Hospital Mannheim, Medical Faculty Mannheim of the University of Heidelberg, 68167 Mannheim, Germany
| | - Johann-Christoph Jann
- Department of Hematology and Oncology, University Hospital Mannheim, Medical Faculty Mannheim of the University of Heidelberg, 68167 Mannheim, Germany
| | - Florian Nolte
- Department of Hematology and Oncology, University Hospital Mannheim, Medical Faculty Mannheim of the University of Heidelberg, 68167 Mannheim, Germany
| | - Simon Raffel
- Heidelberg Institute for Stem Cell Technology and Experimental Medicine (HI-STEM gGmbH), Im Neuenheimer Feld 280, 69120 Heidelberg, German
| | - Carl Herrmann
- Institute of Pharmacy and Molecular Biotechnology, University of Heidelberg, 69120 Heidelberg, Germany; Division of Theoretical Bioinformatics, DKFZ, 69120 Heidelberg, Germany
| | - Amelie Lier
- Heidelberg Institute for Stem Cell Technology and Experimental Medicine (HI-STEM gGmbH), Im Neuenheimer Feld 280, 69120 Heidelberg, German
| | - Christian Eisen
- Heidelberg Institute for Stem Cell Technology and Experimental Medicine (HI-STEM gGmbH), Im Neuenheimer Feld 280, 69120 Heidelberg, German
| | - Verena Nowak
- Department of Hematology and Oncology, University Hospital Mannheim, Medical Faculty Mannheim of the University of Heidelberg, 68167 Mannheim, Germany
| | - Bettina Zens
- Division of Stem Cells and Cancer, Deutsches Krebsforschungszentrum (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany; Heidelberg Institute for Stem Cell Technology and Experimental Medicine (HI-STEM gGmbH), Im Neuenheimer Feld 280, 69120 Heidelberg, German
| | - Katja Müdder
- Division of Stem Cells and Cancer, Deutsches Krebsforschungszentrum (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany; Heidelberg Institute for Stem Cell Technology and Experimental Medicine (HI-STEM gGmbH), Im Neuenheimer Feld 280, 69120 Heidelberg, German
| | - Corinna Klein
- Division of Stem Cells and Cancer, Deutsches Krebsforschungszentrum (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany; Heidelberg Institute for Stem Cell Technology and Experimental Medicine (HI-STEM gGmbH), Im Neuenheimer Feld 280, 69120 Heidelberg, German
| | - Julia Obländer
- Department of Hematology and Oncology, University Hospital Mannheim, Medical Faculty Mannheim of the University of Heidelberg, 68167 Mannheim, Germany
| | - Stephanie Fey
- Department of Hematology and Oncology, University Hospital Mannheim, Medical Faculty Mannheim of the University of Heidelberg, 68167 Mannheim, Germany
| | - Jovita Vogler
- Department of Hematology and Oncology, University Hospital Mannheim, Medical Faculty Mannheim of the University of Heidelberg, 68167 Mannheim, Germany
| | - Alice Fabarius
- Department of Hematology and Oncology, University Hospital Mannheim, Medical Faculty Mannheim of the University of Heidelberg, 68167 Mannheim, Germany
| | - Eva Riedl
- Department of Pathology, University Hospital Mannheim, 68167 Mannheim, Germany
| | - Henning Roehl
- Department of Orthopedics, University Hospital Mannheim, 68167 Mannheim, Germany
| | | | | | | | - Nadine Müller
- Department of Hematology and Oncology, University Hospital Mannheim, Medical Faculty Mannheim of the University of Heidelberg, 68167 Mannheim, Germany
| | - Thilo John
- Department of Traumatology, DRK Hospital Westend, 14050 Berlin, Germany
| | - Uwe Platzbecker
- Technical University Dresden, University Hospital 'Carl Gustav Carus,' Medical Clinic and Policlinic I, 01307 Dresden, Germany
| | - Georgia Metzgeroth
- Department of Hematology and Oncology, University Hospital Mannheim, Medical Faculty Mannheim of the University of Heidelberg, 68167 Mannheim, Germany
| | - Wolf-Karsten Hofmann
- Department of Hematology and Oncology, University Hospital Mannheim, Medical Faculty Mannheim of the University of Heidelberg, 68167 Mannheim, Germany
| | - Andreas Trumpp
- Division of Stem Cells and Cancer, Deutsches Krebsforschungszentrum (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany; Heidelberg Institute for Stem Cell Technology and Experimental Medicine (HI-STEM gGmbH), Im Neuenheimer Feld 280, 69120 Heidelberg, German; German Cancer Consortium, 69120 Heidelberg, Germany.
| | - Daniel Nowak
- Department of Hematology and Oncology, University Hospital Mannheim, Medical Faculty Mannheim of the University of Heidelberg, 68167 Mannheim, Germany
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Medyouf H, Mossner M, Nolte F, Jann J, Nowak V, Zens B, Müdder K, Oblaender J, Fey S, Fabarius A, Riedl E, Marx A, Roehl H, Mueller N, Metzgeroth G, Hütter G, Hofmann W, Trumpp A, Nowak D. O-013 Mesenchymal stromal cells support significant engraftment of low-risk myelodysplastic syndromes (MDS) in a murine xenograft model. Leuk Res 2013. [DOI: 10.1016/s0145-2126(13)70035-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Honeder C, Campregher C, Zens B, Scharl T, Gasche C. Improvement of replication fidelity by certain mesalazine derivatives. Int J Oncol 2012; 40:1331-8. [PMID: 22366868 DOI: 10.3892/ijo.2012.1381] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2011] [Accepted: 09/19/2011] [Indexed: 11/06/2022] Open
Abstract
Epidemiological evidence on the chemopreventive activity of mesalazine against colitis-associated cancer has accumulated in recent years. Together with the variety of mesalazine molecular antitumor effects this has prompted the development of novel mesalazine derivatives. The objective of this study was to test five novel derivatives (compounds 2-14, 2-17, 2-28, 2-34L, 2-39) for their effect on cell proliferation, their capability to scavenge superoxide anions, to induce a cell cycle arrest and to improve replication fidelity in cultured colorectal cells. Compound 2-14 was identified as the strongest inhibitor of cell proliferation and functioned as a potent superoxide scavenger, as did 2-17 and 2-34L. 2-14 induced a G2/M-arrest in HCT116 and a G0/G1-arrest in HT29 cells. 2-17 caused a G0/G1-arrest and 2-34L a G2/M-arrest in HT29 cells. 2-17 and 2-34L reduced mutation rates at a (CA)13 repeat in a dose-dependent fashion. These data suggest that certain mesalazine derivatives share important antitumor effects. From this experimental profile compounds 2-17 and 2-34L both improve replication fidelity, which is biologically relevant not only for colitis-associated cancer but also potentially for individuals with hereditary non-polyposis colorectal cancer.
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Affiliation(s)
- Clemens Honeder
- Christian Doppler Laboratory for Molecular Cancer Chemoprevention, Medical University of Vienna, Vienna, Austria
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