1
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Mannino PJ, Perun A, Surovstev I, Ader NR, Shao L, Melia TJ, King MC, Lusk CP. A quantitative ultrastructural timeline of nuclear autophagy reveals a role for dynamin-like protein 1 at the nuclear envelope. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.14.580336. [PMID: 38405892 PMCID: PMC10888867 DOI: 10.1101/2024.02.14.580336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/27/2024]
Abstract
Autophagic mechanisms that maintain nuclear envelope homeostasis are bulwarks to aging and disease. By leveraging 4D lattice light sheet microscopy and correlative light and electron tomography, we define a quantitative and ultrastructural timeline of a nuclear macroautophagy (nucleophagy) pathway in yeast. Nucleophagy initiates with a rapid local accumulation of the nuclear cargo adaptor Atg39 at the nuclear envelope adjacent to the nucleus-vacuole junction and is delivered to the vacuole in ~300 seconds through an autophagosome intermediate. Mechanistically, nucleophagy incorporates two consecutive and genetically defined membrane fission steps: inner nuclear membrane (INM) fission generates a lumenal vesicle in the perinuclear space followed by outer nuclear membrane (ONM) fission to liberate a double membraned vesicle to the cytosol. ONM fission occurs independently of phagophore engagement and instead relies surprisingly on dynamin-like protein1 (Dnm1), which is recruited to sites of Atg39 accumulation at the nuclear envelope. Loss of Dnm1 compromises nucleophagic flux by stalling nucleophagy after INM fission. Our findings reveal how nuclear and INM cargo are removed from an intact nucleus without compromising its integrity, achieved in part by a non-canonical role for Dnm1 in nuclear envelope remodeling.
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Affiliation(s)
- Philip J. Mannino
- Department of Cell Biology, Yale School of Medicine, 295 Congress Ave, New Haven, CT, 06520
| | - Andrew Perun
- Department of Cell Biology, Yale School of Medicine, 295 Congress Ave, New Haven, CT, 06520
| | - Ivan Surovstev
- Department of Cell Biology, Yale School of Medicine, 295 Congress Ave, New Haven, CT, 06520
- Department of Physics, Yale University, New Haven, CT, 06511
| | - Nicholas R. Ader
- Department of Cell Biology, Yale School of Medicine, 295 Congress Ave, New Haven, CT, 06520
| | - Lin Shao
- Department of Cell Biology, Yale School of Medicine, 295 Congress Ave, New Haven, CT, 06520
| | - Thomas J. Melia
- Department of Cell Biology, Yale School of Medicine, 295 Congress Ave, New Haven, CT, 06520
| | - Megan C. King
- Department of Cell Biology, Yale School of Medicine, 295 Congress Ave, New Haven, CT, 06520
- Department of Molecular Cellular and Developmental Biology, Yale University, New Haven, CT, 06511
| | - C. Patrick Lusk
- Department of Cell Biology, Yale School of Medicine, 295 Congress Ave, New Haven, CT, 06520
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2
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Pal A, Paripati A, Deolal P, Chatterjee A, Prasad PR, Adla P, Sepuri NBV. Eisosome protein Pil1 regulates mitochondrial morphology, mitophagy, and cell death in Saccharomyces cerevisiae. J Biol Chem 2022; 298:102533. [PMID: 36162502 PMCID: PMC9619184 DOI: 10.1016/j.jbc.2022.102533] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Revised: 09/18/2022] [Accepted: 09/19/2022] [Indexed: 12/06/2022] Open
Abstract
Mitochondrial morphology and dynamics maintain mitochondrial integrity by regulating its size, shape, distribution, and connectivity, thereby modulating various cellular processes. Several studies have established a functional link between mitochondrial dynamics, mitophagy, and cell death, but further investigation is needed to identify specific proteins involved in mitochondrial dynamics. Any alteration in the integrity of mitochondria has severe ramifications that include disorders like cancer and neurodegeneration. In this study, we used budding yeast as a model organism and found that Pil1, the major component of the eisosome complex, also localizes to the periphery of mitochondria. Interestingly, the absence of Pil1 causes the branched tubular morphology of mitochondria to be abnormally fused or aggregated, whereas its overexpression leads to mitochondrial fragmentation. Most importantly, pil1Δ cells are defective in mitophagy and bulk autophagy, resulting in elevated levels of reactive oxygen species and protein aggregates. In addition, we show that pil1Δ cells are more prone to cell death. Yeast two-hybrid analysis and co-immunoprecipitations show the interaction of Pil1 with two major proteins in mitochondrial fission, Fis1 and Dnm1. Additionally, our data suggest that the role of Pil1 in maintaining mitochondrial shape is dependent on Fis1 and Dnm1, but it functions independently in mitophagy and cell death pathways. Together, our data suggest that Pil1, an eisosome protein, is a novel regulator of mitochondrial morphology, mitophagy, and cell death.
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Affiliation(s)
- Amita Pal
- Department of Biochemistry, University of Hyderabad, Prof. C.R Rao Road, Gachibowli, Hyderabad, TS -500046
| | - Arunkumar Paripati
- Department of Biochemistry, University of Hyderabad, Prof. C.R Rao Road, Gachibowli, Hyderabad, TS -500046
| | - Pallavi Deolal
- Department of Biochemistry, University of Hyderabad, Prof. C.R Rao Road, Gachibowli, Hyderabad, TS -500046
| | - Arpan Chatterjee
- Department of Biochemistry, University of Hyderabad, Prof. C.R Rao Road, Gachibowli, Hyderabad, TS -500046
| | - Pushpa Rani Prasad
- Department of Biochemistry, University of Hyderabad, Prof. C.R Rao Road, Gachibowli, Hyderabad, TS -500046
| | - Priyanka Adla
- Department of Biochemistry, University of Hyderabad, Prof. C.R Rao Road, Gachibowli, Hyderabad, TS -500046
| | - Naresh Babu V Sepuri
- Department of Biochemistry, University of Hyderabad, Prof. C.R Rao Road, Gachibowli, Hyderabad, TS -500046.
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3
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Correa Tedesco FG, Aguilar PS, Estrada L. Correlation analyses reveal differential diffusion behavior of eisosomal proteins between mother and daughter cells. Methods Appl Fluoresc 2022; 10. [PMID: 36067776 DOI: 10.1088/2050-6120/ac8fe1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2022] [Accepted: 09/05/2022] [Indexed: 11/12/2022]
Abstract
Eisosomes are nanoscale plasma membrane domains shaped as furrow-like invaginations. In Saccharomyces cerevisiae these relatively immobile and uniform structures are mainly composed of two cytoplasmic proteins Pil1 and Lsp1. The present work uses fluctuation of fluorescence signals and analytical methods to determine Pil1 and Lsp1 dynamics at different subcellular locations. Using scanning techniques and autocorrelation analysis we determine that the cytoplasmic pools of Pil1 and Lsp1 behave mainly by passive diffusion. Single-point FCS experiments performed at several subcellular locations reveal that Pil1 mobility is faster in daughter cells. Furthermore, pair correlation function analysis indicates a rapid dynamic of Pil1 near the plasma membrane of growing yeast buds, where the membrane is expected to be actively assembling eisosomes.
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Affiliation(s)
- Francisco G Correa Tedesco
- Laboratorio de Biología Celular de Membranas, Instituto de Investigaciones Biotecnológicas, Universidad Nacional de San Martín, San Martín, Argentina, Campus Miguelete, Buenos Aires, 1650, ARGENTINA
| | - Pablo Sebastian Aguilar
- Laboratorio de Biología Celular de Membranas, Instituto de Investigaciones Biotecnológicas, Universidad Nacional de San Martín, San Martín, Argentina, Campus Miguelete, Buenos Aires, 1650, ARGENTINA
| | - Laura Estrada
- Departamento de Física, Facultad de Ciencias Exactas y Naturales, UBA,, Intendente Guiraldes 2160, Pabellon 1, CABA, Buenos Aires, 1428, ARGENTINA
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4
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Podh NK, Paliwal S, Dey P, Das A, Morjaria S, Mehta G. In-vivo Single-Molecule Imaging in Yeast: Applications and Challenges. J Mol Biol 2021; 433:167250. [PMID: 34537238 DOI: 10.1016/j.jmb.2021.167250] [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: 07/01/2021] [Revised: 09/10/2021] [Accepted: 09/11/2021] [Indexed: 10/20/2022]
Abstract
Single-molecule imaging has gained momentum to quantify the dynamics of biomolecules in live cells, as it provides direct real-time measurements of various cellular activities under their physiological environment. Yeast, a simple and widely used eukaryote, serves as a good model system to quantify single-molecule dynamics of various cellular processes because of its low genomic and cellular complexities, as well as its facile ability to be genetically manipulated. In the past decade, significant developments have been made regarding the intracellular labeling of biomolecules (proteins, mRNA, fatty acids), the microscopy setups to visualize single-molecules and capture their fast dynamics, and the data analysis pipelines to interpret such dynamics. In this review, we summarize the current state of knowledge for the single-molecule imaging in live yeast cells to provide a ready reference for beginners. We provide a comprehensive table to demonstrate how various labs tailored the imaging regimes and data analysis pipelines to estimate various biophysical parameters for a variety of biological processes. Lastly, we present current challenges and future directions for developing better tools and resources for single-molecule imaging in live yeast cells.
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Affiliation(s)
- Nitesh Kumar Podh
- Department of Biotechnology, Indian Institute of Technology Hyderabad, Telangana, India. https://twitter.com/@PodhNitesh
| | - Sheetal Paliwal
- Department of Biotechnology, Indian Institute of Technology Hyderabad, Telangana, India. https://twitter.com/@Sheetal62666036
| | - Partha Dey
- Department of Biotechnology, Indian Institute of Technology Hyderabad, Telangana, India. https://twitter.com/@ParthaD63416958
| | - Ayan Das
- Department of Biotechnology, Indian Institute of Technology Hyderabad, Telangana, India. https://twitter.com/@AyanDas76471821
| | - Shruti Morjaria
- Dr. Vikram Sarabhai Institute of Cell and Molecular Biology, The Maharaja Sayajirao University of Baroda, Vadodara, India. https://twitter.com/@shruti_morjaria
| | - Gunjan Mehta
- Department of Biotechnology, Indian Institute of Technology Hyderabad, Telangana, India.
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5
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Lemière J, Ren Y, Berro J. Rapid adaptation of endocytosis, exocytosis and eisosomes after an acute increase in membrane tension in yeast cells. eLife 2021; 10:62084. [PMID: 33983119 PMCID: PMC9045820 DOI: 10.7554/elife.62084] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Accepted: 05/12/2021] [Indexed: 11/13/2022] Open
Abstract
During clathrin-mediated endocytosis (CME) in eukaryotes, actin assembly is required to overcome large membrane tension and turgor pressure. However, the molecular mechanisms by which the actin machinery adapts to varying membrane tension remain unknown. In addition, how cells reduce their membrane tension when they are challenged by hypotonic shocks remains unclear. We used quantitative microscopy to demonstrate that cells rapidly reduce their membrane tension using three parallel mechanisms. In addition to using their cell wall for mechanical protection, yeast cells disassemble eisosomes to buffer moderate changes in membrane tension on a minute time scale. Meanwhile, a temporary reduction in the rate of endocytosis for 2–6 min and an increase in the rate of exocytosis for at least 5 min allow cells to add large pools of membrane to the plasma membrane. We built on these results to submit the cells to abrupt increases in membrane tension and determine that the endocytic actin machinery of fission yeast cells rapidly adapts to perform CME. Our study sheds light on the tight connection between membrane tension regulation, endocytosis, and exocytosis.
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Affiliation(s)
- Joël Lemière
- Department of Molecular Biophysics and Biochemistry, Department of Cell Biology, Yale University, New Haven, United States
| | - Yuan Ren
- Department of Molecular Biophysics and Biochemistry, Department of Cell Biology, Yale University, New Haven, United States
| | - Julien Berro
- Department of Molecular Biophysics and Biochemistry, Department of Cell Biology, Yale University, New Haven, United States
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6
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Single-molecule FRET imaging of GPCR dimers in living cells. Nat Methods 2021; 18:397-405. [PMID: 33686301 PMCID: PMC8232828 DOI: 10.1038/s41592-021-01081-y] [Citation(s) in RCA: 81] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Accepted: 01/29/2021] [Indexed: 12/18/2022]
Abstract
Class C G protein-coupled receptors (GPCRs) are known to form stable homodimers or heterodimers critical for function, but the oligomeric status of class A and B receptors, which constitute >90% of all GPCRs, remains hotly debated. Single-molecule fluorescence resonance energy transfer (smFRET) is a powerful approach with the potential to reveal valuable insights into GPCR organization but has rarely been used in living cells to study protein systems. Here, we report generally applicable methods for using smFRET to detect and track transmembrane proteins diffusing within the plasma membrane of mammalian cells. We leverage this in-cell smFRET approach to show agonist-induced structural dynamics within individual metabotropic glutamate receptor dimers. We apply these methods to representative class A, B and C receptors, finding evidence for receptor monomers, density-dependent dimers and constitutive dimers, respectively.
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7
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Yang Q, Kempken F. The Composition and the Structure of MCC/Eisosomes in Neurospora crassa. Front Microbiol 2020; 11:2115. [PMID: 33071997 PMCID: PMC7533531 DOI: 10.3389/fmicb.2020.02115] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Accepted: 08/11/2020] [Indexed: 12/15/2022] Open
Abstract
MCC/eisosomes are protein-organized domains in the plasma membrane of fungi and algae. However, the composition and function(s) of MCC/eisosomes in the filamentous fungus Neurospora crassa were previously unknown. To identify proteins that localize to MCC/eisosomes in N. crassa, we isolated proteins that co-purified with the core MCC/eisosome protein LSP-1, which was tagged with GFP. Proteins that co-fractionated with LSP-1:GFP were then identified by mass spectrometry. Eighteen proteins were GFP-tagged and used to identify six proteins that highly colocalized with the MCC/eisosome marker LSP-1:RFP, while five other proteins showed partial overlap with MCC/eisosomes. Seven of these proteins showed amino acid sequence homology with proteins known to localize to MCC/eisosomes in the yeast Saccharomyces cerevisiae. However, homologs of three proteins known to localize to MCC/eisosomes in S. cerevisiae (Can1, Pkh1/2, and Fhn1) were not found to colocalize with MCC/eisosome proteins in N. crassa by fluorescence microscopy. Interestingly, one new eisosome protein (glutamine-fructose-6-phosphate aminotransferase, gene ID: NCU07366) was detected in our studies. These findings demonstrate that there are interspecies differences of the protein composition of MCC/eisosomes. To gain further insight, molecular modeling and bioinformatics analysis of the identified proteins were used to propose the organization of MCC/eisosomes in N. crassa. A model will be discussed for how the broad range of functions predicted for the proteins localized to MCC/eisosomes, including cell wall synthesis, response and signaling, transmembrane transport, and actin organization, suggests that MCC/eisosomes act as organizing centers in the plasma membrane.
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Affiliation(s)
- Qin Yang
- Department of Genetics and Molecular Biology, Botanical Institute and Botanic Garden, Kiel University, Kiel, Germany
| | - Frank Kempken
- Department of Genetics and Molecular Biology, Botanical Institute and Botanic Garden, Kiel University, Kiel, Germany
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8
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Plasma Membrane MCC/Eisosome Domains Promote Stress Resistance in Fungi. Microbiol Mol Biol Rev 2020; 84:84/4/e00063-19. [PMID: 32938742 DOI: 10.1128/mmbr.00063-19] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
There is growing appreciation that the plasma membrane orchestrates a diverse array of functions by segregating different activities into specialized domains that vary in size, stability, and composition. Studies with the budding yeast Saccharomyces cerevisiae have identified a novel type of plasma membrane domain known as the MCC (membrane compartment of Can1)/eisosomes that correspond to stable furrows in the plasma membrane. MCC/eisosomes maintain proteins at the cell surface, such as nutrient transporters like the Can1 arginine symporter, by protecting them from endocytosis and degradation. Recent studies from several fungal species are now revealing new functional roles for MCC/eisosomes that enable cells to respond to a wide range of stressors, including changes in membrane tension, nutrition, cell wall integrity, oxidation, and copper toxicity. The different MCC/eisosome functions are often intertwined through the roles of these domains in lipid homeostasis, which is important for proper plasma membrane architecture and cell signaling. Therefore, this review will emphasize the emerging models that explain how MCC/eisosomes act as hubs to coordinate cellular responses to stress. The importance of MCC/eisosomes is underscored by their roles in virulence for fungal pathogens of plants, animals, and humans, which also highlights the potential of these domains to act as novel therapeutic targets.
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9
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Athanasopoulos A, André B, Sophianopoulou V, Gournas C. Fungal plasma membrane domains. FEMS Microbiol Rev 2020; 43:642-673. [PMID: 31504467 DOI: 10.1093/femsre/fuz022] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Accepted: 08/25/2019] [Indexed: 12/11/2022] Open
Abstract
The plasma membrane (PM) performs a plethora of physiological processes, the coordination of which requires spatial and temporal organization into specialized domains of different sizes, stability, protein/lipid composition and overall architecture. Compartmentalization of the PM has been particularly well studied in the yeast Saccharomyces cerevisiae, where five non-overlapping domains have been described: The Membrane Compartments containing the arginine permease Can1 (MCC), the H+-ATPase Pma1 (MCP), the TORC2 kinase (MCT), the sterol transporters Ltc3/4 (MCL), and the cell wall stress mechanosensor Wsc1 (MCW). Additional cortical foci at the fungal PM are the sites where clathrin-dependent endocytosis occurs, the sites where the external pH sensing complex PAL/Rim localizes, and sterol-rich domains found in apically grown regions of fungal membranes. In this review, we summarize knowledge from several fungal species regarding the organization of the lateral PM segregation. We discuss the mechanisms of formation of these domains, and the mechanisms of partitioning of proteins there. Finally, we discuss the physiological roles of the best-known membrane compartments, including the regulation of membrane and cell wall homeostasis, apical growth of fungal cells and the newly emerging role of MCCs as starvation-protective membrane domains.
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Affiliation(s)
- Alexandros Athanasopoulos
- Microbial Molecular Genetics Laboratory, Institute of Biosciences and Applications, National Centre for Scientific Research 'Demokritos,' Patr. Grigoriou E & 27 Neapoleos St. 15341, Agia Paraskevi, Greece
| | - Bruno André
- Molecular Physiology of the Cell laboratory, Université Libre de Bruxelles (ULB), Institut de Biologie et de Médecine Moléculaires, rue des Pr Jeener et Brachet 12, 6041, Gosselies, Belgium
| | - Vicky Sophianopoulou
- Microbial Molecular Genetics Laboratory, Institute of Biosciences and Applications, National Centre for Scientific Research 'Demokritos,' Patr. Grigoriou E & 27 Neapoleos St. 15341, Agia Paraskevi, Greece
| | - Christos Gournas
- Microbial Molecular Genetics Laboratory, Institute of Biosciences and Applications, National Centre for Scientific Research 'Demokritos,' Patr. Grigoriou E & 27 Neapoleos St. 15341, Agia Paraskevi, Greece
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10
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Lacy MM, Baddeley D, Berro J. Single-molecule turnover dynamics of actin and membrane coat proteins in clathrin-mediated endocytosis. eLife 2019; 8:52355. [PMID: 31855180 PMCID: PMC6977972 DOI: 10.7554/elife.52355] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Accepted: 12/18/2019] [Indexed: 12/22/2022] Open
Abstract
Actin dynamics generate forces to deform the membrane and overcome the cell’s high turgor pressure during clathrin-mediated endocytosis (CME) in yeast, but precise molecular details are still unresolved. Our previous models predicted that actin filaments of the endocytic meshwork continually polymerize and disassemble, turning over multiple times during an endocytic event, similar to other actin systems. We applied single-molecule speckle tracking in live fission yeast to directly measure molecular turnover within CME sites for the first time. In contrast with the overall ~20 s lifetimes of actin and actin-associated proteins in endocytic patches, we detected single-molecule residence times around 1 to 2 s, and similarly high turnover rates of membrane-associated proteins in CME. Furthermore, we find heterogeneous behaviors in many proteins’ motions. These results indicate that endocytic proteins turn over up to five times during the formation of an endocytic vesicle, and suggest revising quantitative models of force production.
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Affiliation(s)
- Michael M Lacy
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, United States.,Nanobiology Institute, Yale University, West Haven, United States.,Integrated Graduate Program in Physical and Engineering Biology, Yale University, New Haven, United States
| | - David Baddeley
- Nanobiology Institute, Yale University, West Haven, United States.,Department of Cell Biology, Yale University School of Medicine, New Haven, United States
| | - Julien Berro
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, United States.,Nanobiology Institute, Yale University, West Haven, United States.,Department of Cell Biology, Yale University School of Medicine, New Haven, United States
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11
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Lacy MM, Baddeley D, Berro J. Single-molecule turnover dynamics of actin and membrane coat proteins in clathrin-mediated endocytosis. eLife 2019; 8. [PMID: 31855180 DOI: 10.1101/617746] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Accepted: 12/18/2019] [Indexed: 05/20/2023] Open
Abstract
Actin dynamics generate forces to deform the membrane and overcome the cell's high turgor pressure during clathrin-mediated endocytosis (CME) in yeast, but precise molecular details are still unresolved. Our previous models predicted that actin filaments of the endocytic meshwork continually polymerize and disassemble, turning over multiple times during an endocytic event, similar to other actin systems. We applied single-molecule speckle tracking in live fission yeast to directly measure molecular turnover within CME sites for the first time. In contrast with the overall ~20 s lifetimes of actin and actin-associated proteins in endocytic patches, we detected single-molecule residence times around 1 to 2 s, and similarly high turnover rates of membrane-associated proteins in CME. Furthermore, we find heterogeneous behaviors in many proteins' motions. These results indicate that endocytic proteins turn over up to five times during the formation of an endocytic vesicle, and suggest revising quantitative models of force production.
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Affiliation(s)
- Michael M Lacy
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, United States
- Nanobiology Institute, Yale University, West Haven, United States
- Integrated Graduate Program in Physical and Engineering Biology, Yale University, New Haven, United States
| | - David Baddeley
- Nanobiology Institute, Yale University, West Haven, United States
- Department of Cell Biology, Yale University School of Medicine, New Haven, United States
| | - Julien Berro
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, United States
- Nanobiology Institute, Yale University, West Haven, United States
- Department of Cell Biology, Yale University School of Medicine, New Haven, United States
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12
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Abstract
Moseley discusses the molecular and mechanical functions of eisosomes - invaginations from the yeast plasma membrane.
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13
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Ebrahimkutty MP, Galic M. Receptor‐Free Signaling at Curved Cellular Membranes. Bioessays 2019; 41:e1900068. [DOI: 10.1002/bies.201900068] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2019] [Revised: 07/09/2019] [Indexed: 11/10/2022]
Affiliation(s)
- Mirsana P. Ebrahimkutty
- DFG Cluster of Excellence “Cells in Motion”University of Muenster Muenster 48149 Germany
- Institute of Medical Physics and BiophysicsUniversity of Muenster Muenster 48149 Germany
- CIM‐IMRPS Graduate School Muenster 48149 Germany
| | - Milos Galic
- DFG Cluster of Excellence “Cells in Motion”University of Muenster Muenster 48149 Germany
- Institute of Medical Physics and BiophysicsUniversity of Muenster Muenster 48149 Germany
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14
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Chan C, Pang X, Zhang Y, Niu T, Yang S, Zhao D, Li J, Lu L, Hsu VW, Zhou J, Sun F, Fan J. ACAP1 assembles into an unusual protein lattice for membrane deformation through multiple stages. PLoS Comput Biol 2019; 15:e1007081. [PMID: 31291238 PMCID: PMC6663034 DOI: 10.1371/journal.pcbi.1007081] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Revised: 07/29/2019] [Accepted: 05/06/2019] [Indexed: 11/19/2022] Open
Abstract
Studies on the Bin-Amphiphysin-Rvs (BAR) domain have advanced a fundamental understanding of how proteins deform membrane. We previously showed that a BAR domain in tandem with a Pleckstrin Homology (PH domain) underlies the assembly of ACAP1 (Arfgap with Coil-coil, Ankryin repeat, and PH domain I) into an unusual lattice structure that also uncovers a new paradigm for how a BAR protein deforms membrane. Here, we initially pursued computation-based refinement of the ACAP1 lattice to identify its critical protein contacts. Simulation studies then revealed how ACAP1, which dimerizes into a symmetrical structure in solution, is recruited asymmetrically to the membrane through dynamic behavior. We also pursued electron microscopy (EM)-based structural studies, which shed further insight into the dynamic nature of the ACAP1 lattice assembly. As ACAP1 is an unconventional BAR protein, our findings broaden the understanding of the mechanistic spectrum by which proteins assemble into higher-ordered structures to achieve membrane deformation.
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Affiliation(s)
- Chun Chan
- Department of Materials Science and Engineering, City University of Hong Kong, Hong Kong, China
| | - Xiaoyun Pang
- National Laboratory of Biomacromolecules, CAS Center for excellence in biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Yan Zhang
- National Laboratory of Biomacromolecules, CAS Center for excellence in biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Tongxin Niu
- National Laboratory of Biomacromolecules, CAS Center for excellence in biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Shengjiang Yang
- School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou, Guangdong, China
| | - Daohui Zhao
- School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou, Guangdong, China
| | - Jian Li
- Division of Rheumatology, Immunology and Allergy, Brigham and Women’s Hospital, and Department of Medicine, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Lanyuan Lu
- School of Biological Sciences, Nanyang Technological University, Singapore
| | - Victor W. Hsu
- Division of Rheumatology, Immunology and Allergy, Brigham and Women’s Hospital, and Department of Medicine, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Jian Zhou
- School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou, Guangdong, China
- * E-mail: (JZ); (FS); (JF)
| | - Fei Sun
- National Laboratory of Biomacromolecules, CAS Center for excellence in biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
- Center for Biological Imaging, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
- * E-mail: (JZ); (FS); (JF)
| | - Jun Fan
- Department of Materials Science and Engineering, City University of Hong Kong, Hong Kong, China
- City University of Hong Kong Shenzhen Research Institute, Shenzhen, China
- Center for Advanced Nuclear Safety and Sustainable Development, City University of Hong Kong, Hong Kong, China
- * E-mail: (JZ); (FS); (JF)
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15
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Simunovic M, Bassereau P, Voth GA. Organizing membrane-curving proteins: the emerging dynamical picture. Curr Opin Struct Biol 2018; 51:99-105. [PMID: 29609179 PMCID: PMC6165709 DOI: 10.1016/j.sbi.2018.03.018] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Revised: 03/16/2018] [Accepted: 03/19/2018] [Indexed: 11/30/2022]
Abstract
Lipid membranes play key roles in cells, such as in trafficking, division, infection, remodeling of organelles, among others. The key step in all these processes is creating membrane curvature, typically under the control of many anchored, adhered or included proteins. However, it has become clear that the membrane itself can mediate the interactions among proteins to produce highly ordered assemblies. Computer simulations are ideally suited to investigate protein organization and the dynamics of membrane remodeling at near-micron scales, something that is extremely challenging to tackle experimentally. We review recent computational efforts in modeling protein-caused membrane deformation mechanisms, specifically focusing on coarse-grained simulations. We highlight work that exposed the membrane-mediated ordering of proteins into lines, meshwork, spirals and other assemblies, in what seems to be a very generic mechanism driven by a combination of short and long-ranged forces. Modulating the mechanical properties of membranes is an underexplored signaling mechanism in various processes deserving of more attention in the near future.
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Affiliation(s)
- Mijo Simunovic
- Department of Chemistry, Institute for Biophysical Dynamics, James Franck Institute and Computation Institute, The University of Chicago, Chicago, IL 60637, USA; Laboratoire Physico Chimie Curie, Institut Curie, PSL Research University, CNRS UMR168, 75005 Paris, France; Sorbonne Universités, UPMC Univ Paris 06, 75005 Paris, France; Center for Studies in Physics and Biology, The Rockefeller University, New York, NY 10065, USA.
| | - Patricia Bassereau
- Laboratoire Physico Chimie Curie, Institut Curie, PSL Research University, CNRS UMR168, 75005 Paris, France; Sorbonne Universités, UPMC Univ Paris 06, 75005 Paris, France
| | - Gregory A Voth
- Department of Chemistry, Institute for Biophysical Dynamics, James Franck Institute and Computation Institute, The University of Chicago, Chicago, IL 60637, USA.
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16
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Bharat TAM, Hoffmann PC, Kukulski W. Correlative Microscopy of Vitreous Sections Provides Insights into BAR-Domain Organization In Situ. Structure 2018; 26:879-886.e3. [PMID: 29681471 PMCID: PMC5992340 DOI: 10.1016/j.str.2018.03.015] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Revised: 02/22/2018] [Accepted: 03/22/2018] [Indexed: 12/15/2022]
Abstract
Electron microscopy imaging of macromolecular complexes in their native cellular context is limited by the inherent difficulty to acquire high-resolution tomographic data from thick cells and to specifically identify elusive structures within crowded cellular environments. Here, we combined cryo-fluorescence microscopy with electron cryo-tomography of vitreous sections into a coherent correlative microscopy workflow, ideal for detection and structural analysis of elusive protein assemblies in situ. We used this workflow to address an open question on BAR-domain coating of yeast plasma membrane compartments known as eisosomes. BAR domains can sense or induce membrane curvature, and form scaffold-like membrane coats in vitro. Our results demonstrate that in cells, the BAR protein Pil1 localizes to eisosomes of varying membrane curvature. Sub-tomogram analysis revealed a dense protein coat on curved eisosomes, which was not present on shallow eisosomes, indicating that while BAR domains can assemble at shallow membranes in vivo, scaffold formation is tightly coupled to curvature generation. Cryo-fluorescence microscopy eases electron cryo-tomography of vitreous sections Elusive protein assemblies are localized in situ by correlative microscopy Yeast BAR-domain protein Pil1 binds to plasma membrane with varying curvature Scaffold-like coats are only seen when Pil1 is bound to high curvature membranes
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Affiliation(s)
- Tanmay A M Bharat
- Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, UK; Central Oxford Structural and Molecular Imaging Centre, South Parks Road, Oxford OX1 3RE, UK; Structural Studies Division, MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | - Patrick C Hoffmann
- Cell Biology Division, MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | - Wanda Kukulski
- Cell Biology Division, MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK.
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17
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Hinrichsen M, Lenz M, Edwards JM, Miller OK, Mochrie SGJ, Swain PS, Schwarz-Linek U, Regan L. A new method for post-translationally labeling proteins in live cells for fluorescence imaging and tracking. Protein Eng Des Sel 2017; 30:771-780. [PMID: 29228311 PMCID: PMC6680098 DOI: 10.1093/protein/gzx059] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Accepted: 11/13/2017] [Indexed: 12/19/2022] Open
Abstract
We present a novel method to fluorescently label proteins, post-translationally, within live Saccharomycescerevisiae. The premise underlying this work is that fluorescent protein (FP) tags are less disruptive to normal processing and function when they are attached post-translationally, because target proteins are allowed to fold properly and reach their final subcellular location before being labeled. We accomplish this post-translational labeling by expressing the target protein fused to a short peptide tag (SpyTag), which is then covalently labeled in situ by controlled expression of an open isopeptide domain (SpyoIPD, a more stable derivative of the SpyCatcher protein) fused to an FP. The formation of a covalent bond between SpyTag and SpyoIPD attaches the FP to the target protein. We demonstrate the general applicability of this strategy by labeling several yeast proteins. Importantly, we show that labeling the membrane protein Pma1 in this manner avoids the mislocalization and growth impairment that occur when Pma1 is genetically fused to an FP. We also demonstrate that this strategy enables a novel approach to spatiotemporal tracking in single cells and we develop a Bayesian analysis to determine the protein's turnover time from such data.
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Affiliation(s)
- M Hinrichsen
- Department of Molecular Biophysics and Biochemistry, Yale University, 266
Whitney Avenue, New Haven, CT 06511, USA
| | - M Lenz
- SynthSys—Synthetic and Systems Biology, School of Biological Sciences,
University of Edinburgh, Edinburgh EH9 3BF, UK
| | - J M Edwards
- Biomedical Sciences Research Complex and School of Biology, University of
St Andrews, North Haugh, St Andrews KY16 9ST, UK
| | - O K Miller
- Biomedical Sciences Research Complex and School of Biology, University of
St Andrews, North Haugh, St Andrews KY16 9ST, UK
| | - S G J Mochrie
- Integrated Graduate Program in Physical and Engineering Biology, Yale
University, New Haven, CT 06511, USA
- Department of Physics, Yale University, 217 Prospect St, New Haven, CT
06511, USA
- Department of Applied Physics, Yale University, 15 Prospect Street, New
Haven, CT 06511, USA
| | - P S Swain
- SynthSys—Synthetic and Systems Biology, School of Biological Sciences,
University of Edinburgh, Edinburgh EH9 3BF, UK
| | - U Schwarz-Linek
- Biomedical Sciences Research Complex and School of Biology, University of
St Andrews, North Haugh, St Andrews KY16 9ST, UK
| | - L Regan
- Department of Molecular Biophysics and Biochemistry, Yale University, 266
Whitney Avenue, New Haven, CT 06511, USA
- Integrated Graduate Program in Physical and Engineering Biology, Yale
University, New Haven, CT 06511, USA
- Department of Chemistry, Yale University, 225 Prospect Street, New Haven,
CT, 06511, USA
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18
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MCC/Eisosomes Regulate Cell Wall Synthesis and Stress Responses in Fungi. J Fungi (Basel) 2017; 3:jof3040061. [PMID: 29371577 PMCID: PMC5753163 DOI: 10.3390/jof3040061] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Revised: 10/26/2017] [Accepted: 10/31/2017] [Indexed: 12/20/2022] Open
Abstract
The fungal plasma membrane is critical for cell wall synthesis and other important processes including nutrient uptake, secretion, endocytosis, morphogenesis, and response to stress. To coordinate these diverse functions, the plasma membrane is organized into specialized compartments that vary in size, stability, and composition. One recently identified domain known as the Membrane Compartment of Can1 (MCC)/eisosome is distinctive in that it corresponds to a furrow-like invagination in the plasma membrane. MCC/eisosomes have been shown to be formed by the Bin/Amphiphysin/Rvs (BAR) domain proteins Lsp1 and Pil1 in a range of fungi. MCC/eisosome domains influence multiple cellular functions; but a very pronounced defect in cell wall synthesis has been observed for mutants with defects in MCC/eisosomes in some yeast species. For example, Candida albicans MCC/eisosome mutants display abnormal spatial regulation of cell wall synthesis, including large invaginations and altered chemical composition of the walls. Recent studies indicate that MCC/eisosomes affect cell wall synthesis in part by regulating the levels of the key regulatory lipid phosphatidylinositol 4,5-bisphosphate (PI4,5P2) in the plasma membrane. One general way MCC/eisosomes function is by acting as protected islands in the plasma membrane, since these domains are very stable. They also act as scaffolds to recruit >20 proteins. Genetic studies aimed at defining the function of the MCC/eisosome proteins have identified important roles in resistance to stress, such as resistance to oxidative stress mediated by the flavodoxin-like proteins Pst1, Pst2, Pst3 and Ycp4. Thus, MCC/eisosomes play multiple roles in plasma membrane organization that protect fungal cells from the environment.
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