1
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Wu YL, Hoess P, Tschanz A, Matti U, Mund M, Ries J. Maximum-likelihood model fitting for quantitative analysis of SMLM data. Nat Methods 2023; 20:139-148. [PMID: 36522500 PMCID: PMC9834062 DOI: 10.1038/s41592-022-01676-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Accepted: 10/14/2022] [Indexed: 12/23/2022]
Abstract
Quantitative data analysis is important for any single-molecule localization microscopy (SMLM) workflow to extract biological insights from the coordinates of the single fluorophores. However, current approaches are restricted to simple geometries or require identical structures. Here, we present LocMoFit (Localization Model Fit), an open-source framework to fit an arbitrary model to localization coordinates. It extracts meaningful parameters from individual structures and can select the most suitable model. In addition to analyzing complex, heterogeneous and dynamic structures for in situ structural biology, we demonstrate how LocMoFit can assemble multi-protein distribution maps of six nuclear pore components, calculate single-particle averages without any assumption about geometry or symmetry, and perform a time-resolved reconstruction of the highly dynamic endocytic process from static snapshots. We provide extensive simulation and visualization routines to validate the robustness of LocMoFit and tutorials to enable any user to increase the information content they can extract from their SMLM data.
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Affiliation(s)
- Yu-Le Wu
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory (EMBL), Heidelberg, Germany
- Collaboration for joint PhD degree between EMBL and Heidelberg University, Faculty of Biosciences, Heidelberg, Germany
| | - Philipp Hoess
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory (EMBL), Heidelberg, Germany
| | - Aline Tschanz
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory (EMBL), Heidelberg, Germany
- Collaboration for joint PhD degree between EMBL and Heidelberg University, Faculty of Biosciences, Heidelberg, Germany
| | - Ulf Matti
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory (EMBL), Heidelberg, Germany
| | - Markus Mund
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory (EMBL), Heidelberg, Germany
- Department of Biochemistry, University of Geneva, Geneva, Switzerland
| | - Jonas Ries
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory (EMBL), Heidelberg, Germany.
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2
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Imaging the Actin Cytoskeleton in Fixed Budding Yeast Cells. Methods Mol Biol 2021; 2364:81-100. [PMID: 34542849 PMCID: PMC10131176 DOI: 10.1007/978-1-0716-1661-1_4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/28/2023]
Abstract
Budding yeast, Saccharomyces cerevisiae, is an appealing model organism to study the organization and function of the actin cytoskeleton. With the advent of techniques to perform high-resolution, multidimensional analysis of the yeast cell, imaging of yeast has emerged as an important tool for research on the cytoskeleton. This chapter describes techniques and approaches for visualizing the actin cytoskeleton in fixed yeast cells with wide-field and super-resolution fluorescence microscopy.
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3
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Möckl L, Moerner WE. Super-resolution Microscopy with Single Molecules in Biology and Beyond-Essentials, Current Trends, and Future Challenges. J Am Chem Soc 2020; 142:17828-17844. [PMID: 33034452 PMCID: PMC7582613 DOI: 10.1021/jacs.0c08178] [Citation(s) in RCA: 82] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Indexed: 12/31/2022]
Abstract
Single-molecule super-resolution microscopy has developed from a specialized technique into one of the most versatile and powerful imaging methods of the nanoscale over the past two decades. In this perspective, we provide a brief overview of the historical development of the field, the fundamental concepts, the methodology required to obtain maximum quantitative information, and the current state of the art. Then, we will discuss emerging perspectives and areas where innovation and further improvement are needed. Despite the tremendous progress, the full potential of single-molecule super-resolution microscopy is yet to be realized, which will be enabled by the research ahead of us.
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Affiliation(s)
- Leonhard Möckl
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - W. E. Moerner
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
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4
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Sun Y, Schöneberg J, Chen X, Jiang T, Kaplan C, Xu K, Pollard TD, Drubin DG. Direct comparison of clathrin-mediated endocytosis in budding and fission yeast reveals conserved and evolvable features. eLife 2019; 8:50749. [PMID: 31829937 PMCID: PMC6908435 DOI: 10.7554/elife.50749] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Accepted: 11/14/2019] [Indexed: 12/13/2022] Open
Abstract
Conserved proteins drive clathrin-mediated endocytosis (CME), which from yeast to humans involves a burst of actin assembly. To gain mechanistic insights into this process, we performed a side-by-side quantitative comparison of CME in two distantly related yeast species. Though endocytic protein abundance in S. pombe and S. cerevisiae is more similar than previously thought, membrane invagination speed and depth are two-fold greater in fission yeast. In both yeasts, accumulation of ~70 WASp molecules activates the Arp2/3 complex to drive membrane invagination. In contrast to budding yeast, WASp-mediated actin nucleation plays an essential role in fission yeast endocytosis. Genetics and live-cell imaging revealed core CME spatiodynamic similarities between the two yeasts, although the assembly of two zones of actin filaments is specific for fission yeast and not essential for CME. These studies identified conserved CME mechanisms and species-specific adaptations with broad implications that are expected to extend from yeast to humans.
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Affiliation(s)
- Yidi Sun
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
| | - Johannes Schöneberg
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
| | - Xuyan Chen
- Department of Chemistry, University of California, Berkeley, Berkeley, United States
| | - Tommy Jiang
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
| | - Charlotte Kaplan
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
| | - Ke Xu
- Department of Chemistry, University of California, Berkeley, Berkeley, United States
| | - Thomas D Pollard
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, United States.,Department of Cell Biology, Yale University, New Haven, United States.,Department of Molecular Cellular and Developmental Biology, Yale University, New Haven, United States
| | - David G Drubin
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
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5
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Thevathasan JV, Kahnwald M, Cieśliński K, Hoess P, Peneti SK, Reitberger M, Heid D, Kasuba KC, Hoerner SJ, Li Y, Wu YL, Mund M, Matti U, Pereira PM, Henriques R, Nijmeijer B, Kueblbeck M, Sabinina VJ, Ellenberg J, Ries J. Nuclear pores as versatile reference standards for quantitative superresolution microscopy. Nat Methods 2019; 16:1045-1053. [PMID: 31562488 PMCID: PMC6768092 DOI: 10.1038/s41592-019-0574-9] [Citation(s) in RCA: 166] [Impact Index Per Article: 33.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Accepted: 08/14/2019] [Indexed: 12/18/2022]
Abstract
Quantitative fluorescence and superresolution microscopy are often limited by insufficient data quality or artifacts. In this context, it is essential to have biologically relevant control samples to benchmark and optimize the quality of microscopes, labels and imaging conditions. Here, we exploit the stereotypic arrangement of proteins in the nuclear pore complex as in situ reference structures to characterize the performance of a variety of microscopy modalities. We created four genome edited cell lines in which we endogenously labeled the nucleoporin Nup96 with mEGFP, SNAP-tag, HaloTag or the photoconvertible fluorescent protein mMaple. We demonstrate their use (1) as three-dimensional resolution standards for calibration and quality control, (2) to quantify absolute labeling efficiencies and (3) as precise reference standards for molecular counting. These cell lines will enable the broader community to assess the quality of their microscopes and labels, and to perform quantitative, absolute measurements.
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Affiliation(s)
- Jervis Vermal Thevathasan
- EMBL, Cell Biology and Biophysics, Heidelberg, Germany
- Faculty of Biosciences, Heidelberg University, Heidelberg, Germany
| | | | | | - Philipp Hoess
- EMBL, Cell Biology and Biophysics, Heidelberg, Germany
- Faculty of Biosciences, Heidelberg University, Heidelberg, Germany
| | - Sudheer Kumar Peneti
- EMBL, Cell Biology and Biophysics, Heidelberg, Germany
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne, UK
| | - Manuel Reitberger
- EMBL, Cell Biology and Biophysics, Heidelberg, Germany
- Division of Stem Cells and Cancer, German Cancer Research Center, Heidelberg, Germany
| | - Daniel Heid
- EMBL, Cell Biology and Biophysics, Heidelberg, Germany
- Department for Applied Tumor Biology, Heidelberg University Hospital, Heidelberg, Germany
| | - Krishna Chaitanya Kasuba
- EMBL, Cell Biology and Biophysics, Heidelberg, Germany
- Eidgenössische Technische Hochschule Zurich, Department of Biosystems Science and Engineering, Basel, Switzerland
| | - Sarah Janice Hoerner
- EMBL, Cell Biology and Biophysics, Heidelberg, Germany
- Institute of Molecular and Cell Biology, Mannheim University of Applied Sciences and Interdisciplinary Center for Neuroscience, Heidelberg University, Heidelberg, Germany
| | - Yiming Li
- EMBL, Cell Biology and Biophysics, Heidelberg, Germany
| | - Yu-Le Wu
- EMBL, Cell Biology and Biophysics, Heidelberg, Germany
- Faculty of Biosciences, Heidelberg University, Heidelberg, Germany
| | - Markus Mund
- EMBL, Cell Biology and Biophysics, Heidelberg, Germany
- Department of Biochemistry, University of Geneva, Science 2, Genève, Switzerland
| | - Ulf Matti
- EMBL, Cell Biology and Biophysics, Heidelberg, Germany
| | - Pedro Matos Pereira
- MRC-Laboratory for Molecular Cell Biology, University College London, London, UK
| | - Ricardo Henriques
- MRC-Laboratory for Molecular Cell Biology, University College London, London, UK
| | | | | | | | - Jan Ellenberg
- EMBL, Cell Biology and Biophysics, Heidelberg, Germany
| | - Jonas Ries
- EMBL, Cell Biology and Biophysics, Heidelberg, Germany.
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6
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Manenschijn HE, Picco A, Mund M, Rivier-Cordey AS, Ries J, Kaksonen M. Type-I myosins promote actin polymerization to drive membrane bending in endocytosis. eLife 2019; 8:44215. [PMID: 31385806 PMCID: PMC6684269 DOI: 10.7554/elife.44215] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Accepted: 07/23/2019] [Indexed: 12/24/2022] Open
Abstract
Clathrin-mediated endocytosis in budding yeast requires the formation of a dynamic actin network that produces the force to invaginate the plasma membrane against the intracellular turgor pressure. The type-I myosins Myo3 and Myo5 are important for endocytic membrane reshaping, but mechanistic details of their function remain scarce. Here, we studied the function of Myo3 and Myo5 during endocytosis using quantitative live-cell imaging and genetic perturbations. We show that the type-I myosins promote, in a dose-dependent way, the growth and expansion of the actin network, which controls the speed of membrane and coat internalization. We found that this myosin-activity is independent of the actin nucleation promoting activity of myosins, and cannot be compensated for by increasing actin nucleation. Our results suggest a new mechanism for type-I myosins to produce force by promoting actin filament polymerization.
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Affiliation(s)
- Hetty E Manenschijn
- Department of Biochemistry, University of Geneva, Geneva, Switzerland.,Cell Biology and Biophysics Unit, European Molecular Biology Laboratory (EMBL), Heidelberg, Germany
| | - Andrea Picco
- Department of Biochemistry, University of Geneva, Geneva, Switzerland.,NCCR Chemical Biology, University of Geneva, Geneva, Switzerland
| | - Markus Mund
- Department of Biochemistry, University of Geneva, Geneva, Switzerland.,Cell Biology and Biophysics Unit, European Molecular Biology Laboratory (EMBL), Heidelberg, Germany
| | | | - Jonas Ries
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory (EMBL), Heidelberg, Germany
| | - Marko Kaksonen
- Department of Biochemistry, University of Geneva, Geneva, Switzerland.,NCCR Chemical Biology, University of Geneva, Geneva, Switzerland
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7
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Bykov YS, Cohen N, Gabrielli N, Manenschijn H, Welsch S, Chlanda P, Kukulski W, Patil KR, Schuldiner M, Briggs JAG. High-throughput ultrastructure screening using electron microscopy and fluorescent barcoding. J Cell Biol 2019; 218:2797-2811. [PMID: 31289126 PMCID: PMC6683748 DOI: 10.1083/jcb.201812081] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Revised: 05/28/2019] [Accepted: 06/11/2019] [Indexed: 01/24/2023] Open
Abstract
Genetic screens using high-throughput fluorescent microscopes have generated large datasets, contributing many cell biological insights. Such approaches cannot tackle questions requiring knowledge of ultrastructure below the resolution limit of fluorescent microscopy. Electron microscopy (EM) reveals detailed cellular ultrastructure but requires time-consuming sample preparation, limiting throughput. Here we describe a robust method for screening by high-throughput EM. Our approach uses combinations of fluorophores as barcodes to uniquely mark each cell type in mixed populations and correlative light and EM (CLEM) to read the barcode of each cell before it is imaged by EM. Coupled with an easy-to-use software workflow for correlation, segmentation, and computer image analysis, our method, called "MultiCLEM," allows us to extract and analyze multiple cell populations from each EM sample preparation. We demonstrate several uses for MultiCLEM with 15 different yeast variants. The methodology is not restricted to yeast, can be scaled to higher throughput, and can be used in multiple ways to enable EM to become a powerful screening technique.
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Affiliation(s)
- Yury S Bykov
- Structural and Computational Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany.,Structural Studies Division, Medical Research Council Laboratory of Molecular Biology, Cambridge Biomedical Campus, Cambridge, UK
| | - Nir Cohen
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | - Natalia Gabrielli
- Structural and Computational Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Hetty Manenschijn
- Structural and Computational Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany.,Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Sonja Welsch
- Structural and Computational Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Petr Chlanda
- Structural and Computational Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Wanda Kukulski
- Structural and Computational Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany.,Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Kiran R Patil
- Structural and Computational Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Maya Schuldiner
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | - John A G Briggs
- Structural and Computational Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany .,Structural Studies Division, Medical Research Council Laboratory of Molecular Biology, Cambridge Biomedical Campus, Cambridge, UK.,Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Heidelberg, Germany
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8
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Mund M, van der Beek JA, Deschamps J, Dmitrieff S, Hoess P, Monster JL, Picco A, Nédélec F, Kaksonen M, Ries J. Systematic Nanoscale Analysis of Endocytosis Links Efficient Vesicle Formation to Patterned Actin Nucleation. Cell 2018; 174:884-896.e17. [PMID: 30057119 PMCID: PMC6086932 DOI: 10.1016/j.cell.2018.06.032] [Citation(s) in RCA: 122] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Revised: 02/27/2018] [Accepted: 06/13/2018] [Indexed: 11/18/2022]
Abstract
Clathrin-mediated endocytosis is an essential cellular function in all eukaryotes that is driven by a self-assembled macromolecular machine of over 50 different proteins in tens to hundreds of copies. How these proteins are organized to produce endocytic vesicles with high precision and efficiency is not understood. Here, we developed high-throughput superresolution microscopy to reconstruct the nanoscale structural organization of 23 endocytic proteins from over 100,000 endocytic sites in yeast. We found that proteins assemble by radially ordered recruitment according to function. WASP family proteins form a circular nanoscale template on the membrane to spatially control actin nucleation during vesicle formation. Mathematical modeling of actin polymerization showed that this WASP nano-template optimizes force generation for membrane invagination and substantially increases the efficiency of endocytosis. Such nanoscale pre-patterning of actin nucleation may represent a general design principle for directional force generation in membrane remodeling processes such as during cell migration and division.
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Affiliation(s)
- Markus Mund
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory (EMBL), Meyerhofstrasse 1, 69117 Heidelberg, Germany
| | - Johannes Albertus van der Beek
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory (EMBL), Meyerhofstrasse 1, 69117 Heidelberg, Germany
| | - Joran Deschamps
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory (EMBL), Meyerhofstrasse 1, 69117 Heidelberg, Germany
| | - Serge Dmitrieff
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory (EMBL), Meyerhofstrasse 1, 69117 Heidelberg, Germany
| | - Philipp Hoess
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory (EMBL), Meyerhofstrasse 1, 69117 Heidelberg, Germany; Collaboration for joint PhD degree between EMBL and Heidelberg University, Faculty of Biosciences
| | - Jooske Louise Monster
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory (EMBL), Meyerhofstrasse 1, 69117 Heidelberg, Germany
| | - Andrea Picco
- Department of Biochemistry and NCCR Chemical Biology, University of Geneva, Quai Ernest Ansermet 30, 1211 Geneva, Switzerland
| | - François Nédélec
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory (EMBL), Meyerhofstrasse 1, 69117 Heidelberg, Germany
| | - Marko Kaksonen
- Department of Biochemistry and NCCR Chemical Biology, University of Geneva, Quai Ernest Ansermet 30, 1211 Geneva, Switzerland
| | - Jonas Ries
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory (EMBL), Meyerhofstrasse 1, 69117 Heidelberg, Germany.
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9
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Abstract
The budding yeast Saccharomyces cerevisiae is widely used as a model system to study the organization and function of the cytoskeleton. In the past, its small size, rounded shape, and rigid cell wall created obstacles to explore the cell biology of this model eukaryote. It is now possible to acquire and analyze high-resolution and super-resolution multidimensional images of the yeast cell. As a result, imaging of yeast has emerged as an important tool in eukaryotic cell biology. This chapter describes labeling methods and optical approaches for visualizing the cytoskeleton and interactions of the actin cytoskeleton with mitochondria in fixed yeast cells using wide-field and super-resolution fluorescence microscopy.
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10
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Kaplan C, Ewers H. Optimized sample preparation for single-molecule localization-based superresolution microscopy in yeast. Nat Protoc 2015; 10:1007-21. [DOI: 10.1038/nprot.2015.060] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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11
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Picco A, Mund M, Ries J, Nédélec F, Kaksonen M. Visualizing the functional architecture of the endocytic machinery. eLife 2015; 4. [PMID: 25675087 PMCID: PMC4357291 DOI: 10.7554/elife.04535] [Citation(s) in RCA: 82] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2014] [Accepted: 02/10/2015] [Indexed: 01/08/2023] Open
Abstract
Clathrin-mediated endocytosis is an essential process that forms vesicles from the plasma membrane. Although most of the protein components of the endocytic protein machinery have been thoroughly characterized, their organization at the endocytic site is poorly understood. We developed a fluorescence microscopy method to track the average positions of yeast endocytic proteins in relation to each other with a time precision below 1 s and with a spatial precision of ∼10 nm. With these data, integrated with shapes of endocytic membrane intermediates and with superresolution imaging, we could visualize the dynamic architecture of the endocytic machinery. We showed how different coat proteins are distributed within the coat structure and how the assembly dynamics of N-BAR proteins relate to membrane shape changes. Moreover, we found that the region of actin polymerization is located at the base of the endocytic invagination, with the growing ends of filaments pointing toward the plasma membrane. DOI:http://dx.doi.org/10.7554/eLife.04535.001 Cells take up proteins and other useful material (called cargo) from their external environment through a process known as endocytosis. To start with, the cargo accumulates in a patch on the surface of the cell. On the inner side of the cell's membrane, a protein called clathrin gathers around the patch of cargo. Clathrin molecules and many other proteins bind together to make a lattice-like coat that causes the membrane to curve inwards and form a pocket that contains the cargo. This continues until the cargo is completely surrounded by membrane and eventually forms a bubble-like structure, or ‘vesicle’, that moves into the cell. More than 50 other proteins are involved in the endocytosis. These proteins arrive at the site of endocytosis in a particular order, complete their tasks and then move away to be used in further rounds of endocytosis. It is not clear how these proteins are organized to complete these steps because it is technically difficult to track the movements of many proteins at the same time. Here, Picco et al. developed a new fluorescence microscopy method that enabled them to track the positions of many of the proteins involved in endocytosis in yeast cells in real time. The experiments revealed when the proteins arrived at the site of endocytosis and how they assembled in relation to the membrane. For example, a group of proteins called N-BAR proteins formed an extended lattice covering the sides of the pocket that forms as the membrane curves inwards. To transform the flat membrane into a vesicle, a network of filaments made of a protein called actin needs to form at the site of endocytosis. The new method shows that the actin filaments grow in a small region at the base of the developing vesicle. By combining different types of microscopy data, Picco et al. were able to build a comprehensive model describing when the proteins involved in endocytosis move and assemble. The next challenge will be to understand the physics behind the molecular machine composed of these many proteins and the cell membrane. DOI:http://dx.doi.org/10.7554/eLife.04535.002
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Affiliation(s)
- Andrea Picco
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Markus Mund
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Jonas Ries
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - François Nédélec
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Marko Kaksonen
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Heidelberg, Germany
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