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Zaferani M, Song R, Petry S, Stone HA. Building on-chip cytoskeletal circuits via branched microtubule networks. Proc Natl Acad Sci U S A 2024; 121:e2315992121. [PMID: 38232292 PMCID: PMC10823238 DOI: 10.1073/pnas.2315992121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Accepted: 12/18/2023] [Indexed: 01/19/2024] Open
Abstract
Controllable platforms to engineer robust cytoskeletal scaffolds have the potential to create novel on-chip nanotechnologies. Inspired by axons, we combined the branching microtubule (MT) nucleation pathway with microfabrication to develop "cytoskeletal circuits." This active matter platform allows control over the adaptive self-organization of uniformly polarized MT arrays via geometric features of microstructures designed within a microfluidic confinement. We build and characterize basic elements, including turns and divisions, as well as complex regulatory elements, such as biased division and MT diodes, to construct various MT architectures on a chip. Our platform could be used in diverse applications, ranging from efficient on-chip molecular transport to mechanical nano-actuators. Further, cytoskeletal circuits can serve as a tool to study how the physical environment contributes to MT architecture in living cells.
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Affiliation(s)
- Meisam Zaferani
- Department of Molecular Biology, Princeton University, Princeton, NJ08544
- Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, NJ08544
- Omenn-Darling Bioengineering Institute, Princeton University, Princeton, NJ08544
| | - Ryungeun Song
- Department of Molecular Biology, Princeton University, Princeton, NJ08544
- Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, NJ08544
| | - Sabine Petry
- Department of Molecular Biology, Princeton University, Princeton, NJ08544
| | - Howard A. Stone
- Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, NJ08544
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2
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Mahserejian SM, Scripture JP, Mauro AJ, Lawrence EJ, Jonasson EM, Murray KS, Li J, Gardner M, Alber M, Zanic M, Goodson HV. Quantification of Microtubule Stutters: Dynamic Instability Behaviors that are Strongly Associated with Catastrophe. Mol Biol Cell 2022; 33:ar22. [PMID: 35108073 PMCID: PMC9250389 DOI: 10.1091/mbc.e20-06-0348] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Microtubules (MTs) are cytoskeletal fibers that undergo dynamic instability (DI), a remarkable process involving phases of growth and shortening separated by stochastic transitions called catastrophe and rescue. Dissecting DI mechanism(s) requires first characterizing and quantifying these dynamics, a subjective process that often ignores complexity in MT behavior. We present a Statistical Tool for Automated Dynamic Instability Analysis (STADIA) that identifies and quantifies not only growth and shortening, but also a category of intermediate behaviors that we term “stutters.” During stutters, the rate of MT length change tends to be smaller in magnitude than during typical growth or shortening phases. Quantifying stutters and other behaviors with STADIA demonstrates that stutters precede most catastrophes in our in vitro experiments and dimer-scale MT simulations, suggesting that stutters are mechanistically involved in catastrophes. Related to this idea, we show that the anticatastrophe factor CLASP2γ works by promoting the return of stuttering MTs to growth. STADIA enables more comprehensive and data-driven analysis of MT dynamics compared with previous methods. The treatment of stutters as distinct and quantifiable DI behaviors provides new opportunities for analyzing mechanisms of MT dynamics and their regulation by binding proteins.
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Affiliation(s)
- Shant M Mahserejian
- Department of Applied and Computational Mathematics and Statistics, University of Notre Dame, IN 46556.,Pacific Northwest National Laboratory, Richland, WA 99352
| | - Jared P Scripture
- Department of Chemistry and Biochemistry, University of Notre Dame, IN 46556
| | - Ava J Mauro
- Department of Chemistry and Biochemistry, University of Notre Dame, IN 46556.,Department of Mathematics and Statistics, University of Massachusetts Amherst, Amherst MA, 01003
| | - Elizabeth J Lawrence
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN 37240
| | - Erin M Jonasson
- Department of Chemistry and Biochemistry, University of Notre Dame, IN 46556.,Department of Natural Sciences, Saint Martin's University, Lacey, WA 98503
| | - Kristopher S Murray
- Department of Chemistry and Biochemistry, University of Notre Dame, IN 46556
| | - Jun Li
- Department of Applied and Computational Mathematics and Statistics, University of Notre Dame, IN 46556
| | - Melissa Gardner
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455
| | - Mark Alber
- Department of Applied and Computational Mathematics and Statistics, University of Notre Dame, IN 46556.,Department of Mathematics, University of California Riverside, Riverside, CA 92521
| | - Marija Zanic
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN 37240.,Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN 37235.,Department of Biochemistry, Vanderbilt University, Nashville, TN 37205
| | - Holly V Goodson
- Department of Chemistry and Biochemistry, University of Notre Dame, IN 46556
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3
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Aulner N, Danckaert A, Fernandes J, Nicola MA, Roux P, Salles A, Tinevez JY, Shorte SL. Fluorescence imaging host pathogen interactions: fifteen years benefit of hindsight…. Curr Opin Microbiol 2018; 43:193-198. [PMID: 29567588 DOI: 10.1016/j.mib.2018.03.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2017] [Revised: 03/01/2018] [Accepted: 03/02/2018] [Indexed: 01/24/2023]
Abstract
We consider in review current state-of-the-art fluorescence microscopy for investigating the host-pathogen interface. Our perspective is honed from years with literally thousands of microbiologists using the variety of imaging technologies available within our dedicated BSL2/BSL3 optical imaging research service facilities at the Institut Pasteur Paris founded from scratch in 2001. During fifteen years learning from the success and failures of introducing different fluorescence imaging technologies, methods, and technical development strategies we provide here a synopsis review of our experience to date and a synthesis of how we see the future in perspective for fluorescence imaging at the host-pathogen interface.
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Affiliation(s)
- Nathalie Aulner
- Institut Pasteur, Citech, Imagopole-UTechS-PBI Photonic BioImaging, 25-28 rue du Dr Roux, 75015 Paris, France
| | - Anne Danckaert
- Institut Pasteur, Citech, Imagopole-UTechS-PBI Photonic BioImaging, 25-28 rue du Dr Roux, 75015 Paris, France
| | - Julien Fernandes
- Institut Pasteur, Citech, Imagopole-UTechS-PBI Photonic BioImaging, 25-28 rue du Dr Roux, 75015 Paris, France
| | - Marie-Anne Nicola
- Institut Pasteur, Citech, Imagopole-UTechS-PBI Photonic BioImaging, 25-28 rue du Dr Roux, 75015 Paris, France
| | - Pascal Roux
- Institut Pasteur, Citech, Imagopole-UTechS-PBI Photonic BioImaging, 25-28 rue du Dr Roux, 75015 Paris, France
| | - Audrey Salles
- Institut Pasteur, Citech, Imagopole-UTechS-PBI Photonic BioImaging, 25-28 rue du Dr Roux, 75015 Paris, France
| | - Jean-Yves Tinevez
- Institut Pasteur, Citech, Imagopole-UTechS-PBI Photonic BioImaging, 25-28 rue du Dr Roux, 75015 Paris, France
| | - Spencer L Shorte
- Institut Pasteur, Citech, Imagopole-UTechS-PBI Photonic BioImaging, 25-28 rue du Dr Roux, 75015 Paris, France
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4
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Spatial confinement of active microtubule networks induces large-scale rotational cytoplasmic flow. Proc Natl Acad Sci U S A 2017; 114:2922-2927. [PMID: 28265076 DOI: 10.1073/pnas.1616001114] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Collective behaviors of motile units through hydrodynamic interactions induce directed fluid flow on a larger length scale than individual units. In cells, active cytoskeletal systems composed of polar filaments and molecular motors drive fluid flow, a process known as cytoplasmic streaming. The motor-driven elongation of microtubule bundles generates turbulent-like flow in purified systems; however, it remains unclear whether and how microtubule bundles induce large-scale directed flow like the cytoplasmic streaming observed in cells. Here, we adopted Xenopus egg extracts as a model system of the cytoplasm and found that microtubule bundle elongation induces directed flow for which the length scale and timescale depend on the existence of geometrical constraints. At the lower activity of dynein, kinesins bundle and slide microtubules, organizing extensile microtubule bundles. In bulk extracts, the extensile bundles connected with each other and formed a random network, and vortex flows with a length scale comparable to the bundle length continually emerged and persisted for 1 min at multiple places. When the extracts were encapsulated in droplets, the extensile bundles pushed the droplet boundary. This pushing force initiated symmetry breaking of the randomly oriented bundle network, leading to bundles aligning into a rotating vortex structure. This vortex induced rotational cytoplasmic flows on the length scale and timescale that were 10- to 100-fold longer than the vortex flows emerging in bulk extracts. Our results suggest that microtubule systems use not only hydrodynamic interactions but also mechanical interactions to induce large-scale temporally stable cytoplasmic flow.
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5
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Pampaloni F, Chang BJ, Stelzer EHK. Light sheet-based fluorescence microscopy (LSFM) for the quantitative imaging of cells and tissues. Cell Tissue Res 2015; 360:129-41. [DOI: 10.1007/s00441-015-2144-5] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Accepted: 02/02/2015] [Indexed: 01/04/2023]
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Lemon WC, Keller PJ. Live imaging of nervous system development and function using light-sheet microscopy. Mol Reprod Dev 2013; 82:605-18. [PMID: 23996352 DOI: 10.1002/mrd.22258] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2013] [Accepted: 08/21/2013] [Indexed: 12/21/2022]
Abstract
In vivo imaging applications typically require carefully balancing conflicting parameters. Often it is necessary to achieve high imaging speed, low photo-bleaching, and photo-toxicity, good three-dimensional resolution, high signal-to-noise ratio, and excellent physical coverage at the same time. Light-sheet microscopy provides good performance in all of these categories, and is thus emerging as a particularly powerful live imaging method for the life sciences. We see an outstanding potential for applying light-sheet microscopy to the study of development and function of the early nervous system in vertebrates and higher invertebrates. Here, we review state-of-the-art approaches to live imaging of early development, and show how the unique capabilities of light-sheet microscopy can further advance our understanding of the development and function of the nervous system. We discuss key considerations in the design of light-sheet microscopy experiments, including sample preparation and fluorescent marker strategies, and provide an outlook for future directions in the field.
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Affiliation(s)
- William C Lemon
- Howard Hughes Medical Institute, Janelia Farm Research Campus, Ashburn, Virginia
| | - Philipp J Keller
- Howard Hughes Medical Institute, Janelia Farm Research Campus, Ashburn, Virginia
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POELERT SANDERL, WEINANS HARRIEH, ZADPOOR AMIRA. FINITE ELEMENT MODELING OF THE THERMAL FLUCTUATIONS OF A SINGLE ANISOTROPIC POLYMER. J MECH MED BIOL 2013. [DOI: 10.1142/s0219519413500565] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Thermal fluctuations of microtubules (MTs) and other cytoskeletal filaments govern to a great extent the complex rheological properties of the cytoskeleton in eukaryotic cells. In recent years, much effort has been put into capturing the dynamics of these fluctuations by means of analytical and numerical models. These attempts have been very successful for, but also remain limited to, isotropic polymers. To correctly interpret experimental work on (strongly) anisotropic semiflexible polymers, there is a need for a numerical modeling tool that accurately captures the dynamics of polymers with anisotropic material properties. In the current study, we present a finite element (FE) framework for simulating the thermal dynamics of a single anisotropic semiflexible polymer. First, we demonstrated the accuracy of our framework by comparison of the simulated mean square displacement (MSD) of the end-to-end distance with analytical predictions based on the worm-like chain model. Then, we implemented a transversely isotropic material model, characteristic for biopolymers such as MTs, and studied the persistence length for various ratios between the longitudinal shear modulus, G12, and corresponding Young's modulus, E1. Finally, we put our findings in context by addressing a recent experimental work on grafted transversely isotropic MTs. In that research, a simplified static mechanical model was used to deduce a very high level of MT anisotropy to explain the observation that the persistence length of grafted MTs increases as contour length increases. We showed, by means of our FE framework, that the anisotropic properties cannot account for the reported length-dependent persistence length.
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Affiliation(s)
- SANDER L. POELERT
- Department of Biomechanical Engineering, Faculty of Mechanical, Maritime and Materials Engineering, Delft University of Technology, Mekelweg 2, Delft 2628 CD, The Netherlands
| | - HARRIE H. WEINANS
- Department of Biomechanical Engineering, Faculty of Mechanical, Maritime and Materials Engineering, Delft University of Technology, Mekelweg 2, Delft 2628 CD, The Netherlands
| | - AMIR A. ZADPOOR
- Department of Biomechanical Engineering, Faculty of Mechanical, Maritime and Materials Engineering, Delft University of Technology, Mekelweg 2, Delft 2628 CD, The Netherlands
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A multiple model probability hypothesis density tracker for time-lapse cell microscopy sequences. INFORMATION PROCESSING IN MEDICAL IMAGING : PROCEEDINGS OF THE ... CONFERENCE 2013. [PMID: 24683962 DOI: 10.1007/978-3-642-38868-2_10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register]
Abstract
Quantitative analysis of the dynamics of tiny cellular and subcellular structures in time-lapse cell microscopy sequences requires the development of a reliable multi-target tracking method capable of tracking numerous similar targets in the presence of high levels of noise, high target density, maneuvering motion patterns and intricate interactions. The linear Gaussian jump Markov system probability hypothesis density (LGJMS-PHD) filter is a recent Bayesian tracking filter that is well-suited for this task. However, the existing recursion equations for this filter do not consider a state-dependent transition probability matrix. As required in many biological applications, we propose a new closed-form recursion that incorporates this assumption and introduce a general framework for particle tracking using the proposed filter. We apply our scheme to multi-target tracking in total internal reflection fluorescence microscopy (TIRFM) sequences and evaluate the performance of our filter against the existing LGJMS-PHD and IMM-JPDA filters.
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10
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Abstract
Light sheet-based fluorescence microscopy (LSFM) is emerging as a powerful imaging technique for the life sciences. LSFM provides an exceptionally high imaging speed, high signal-to-noise ratio, low level of photo-bleaching, and good optical penetration depth. This unique combination of capabilities makes light sheet-based microscopes highly suitable for live imaging applications. Here, we provide an overview of light sheet-based microscopy assays for in vitro and in vivo imaging of biological samples, including cell extracts, soft gels, and large multicellular organisms. We furthermore describe computational tools for basic image processing and data inspection.
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Affiliation(s)
- Raju Tomer
- Janelia Farm Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
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11
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Mohrbach H, Johner A, Kulić IM. Cooperative lattice dynamics and anomalous fluctuations of microtubules. EUROPEAN BIOPHYSICS JOURNAL: EBJ 2011; 41:217-39. [PMID: 22173449 DOI: 10.1007/s00249-011-0778-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2011] [Revised: 11/19/2011] [Accepted: 11/22/2011] [Indexed: 12/27/2022]
Abstract
Microtubules have been in the focus of biophysical research for several decades. However, the confusing and mutually contradictory results regarding their elasticity and fluctuations have cast doubt on their present understanding. In this paper, we present the empirical evidence for the existence of discrete guanosine diphosphate (GDP)-tubulin fluctuations between a curved and a straight configuration at room temperature as well as for conformational tubulin cooperativity. Guided by a number of experimental findings, we build the case for a novel microtubule model, with the principal result that microtubules can spontaneously form micron-sized cooperative helical states with unique elastic and dynamic features. The polymorphic dynamics of the microtubule lattice resulting from the tubulin bistability quantitatively explains several experimental puzzles, including anomalous scaling of dynamic fluctuations of grafted microtubules, their apparent length-stiffness relation, and their remarkable curved-helical appearance in general. We point out that the multistability and cooperative switching of tubulin dimers could participate in important cellular processes, and could in particular lead to efficient mechanochemical signaling along single microtubules.
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Affiliation(s)
- Hervé Mohrbach
- Groupe BioPhysStat, Université Paul Verlaine-Metz, 57078, Metz, France
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12
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Khairy K, Keller PJ. Reconstructing embryonic development. Genesis 2011; 49:488-513. [DOI: 10.1002/dvg.20698] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2010] [Revised: 11/22/2010] [Accepted: 11/24/2010] [Indexed: 01/22/2023]
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13
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Mohrbach H, Johner A, Kulić IM. Tubulin bistability and polymorphic dynamics of microtubules. PHYSICAL REVIEW LETTERS 2010; 105:268102. [PMID: 21231714 DOI: 10.1103/physrevlett.105.268102] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2010] [Indexed: 05/30/2023]
Abstract
Based on the hypothesis that the GDP-tubulin dimer is a conformationally bistable molecule-rapidly fluctuating between a discrete curved and a straight state-we develop a model for polymorphic dynamics of the microtubule lattice. We show that GDP-tubulin bistability consistently explains unusual dynamic fluctuations, the apparent length-stiffness relation of grafted taxol-stabilized microtubules, and the curved-helical appearance of microtubules in general. When clamped by one end the microtubules undergo an unusual zero energy motion-in its effect reminiscent of a limited rotational hinge. We conclude that microtubules exist in highly cooperative energy-degenerate helical states and discuss possible implications in vivo.
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Affiliation(s)
- Hervé Mohrbach
- Groupe BioPhysStat, Université Paul Verlaine, Metz, France
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14
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Tischer C, Ten Wolde PR, Dogterom M. Providing positional information with active transport on dynamic microtubules. Biophys J 2010; 99:726-35. [PMID: 20682249 DOI: 10.1016/j.bpj.2010.05.026] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2009] [Revised: 04/15/2010] [Accepted: 05/12/2010] [Indexed: 12/24/2022] Open
Abstract
Microtubules (MTs) are dynamic protein polymers that change their length by switching between growing and shrinking states in a process termed dynamic instability. It has been suggested that the dynamic properties of MTs are central to the organization of the eukaryotic intracellular space, and that they are involved in the control of cell morphology, but the actual mechanisms are not well understood. Here, we present a theoretical analysis in which we explore the possibility that a system of dynamic MTs and MT end-tracking molecular motors is providing specific positional information inside cells. We compute the MT length distribution for the case of MT-length-dependent switching between growing and shrinking states, and analyze the accumulation of molecular motors at the tips of growing MTs. Using these results, we show that a transport system consisting of dynamic MTs and associated motor proteins can deliver cargo proteins preferentially to specific positions within the cell. Comparing our results with experimental data in the model organism fission yeast, we propose that the suggested mechanisms could play important roles in setting length scales during cellular morphogenesis.
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Affiliation(s)
- Christian Tischer
- Institute for Atomic and Molecular Physics, Foundation for Fundamental Research on Matter, Amsterdam, The Netherlands.
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Parton RM, Vallés AM, Dobbie IM, Davis I. Live cell imaging in Drosophila melanogaster. Cold Spring Harb Protoc 2010; 2010:pdb.top75. [PMID: 20360379 DOI: 10.1101/pdb.top75] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Although many of the techniques of live cell imaging in Drosophila melanogaster are also used by the greater community of cell biologists working on other model systems, studying living fly tissues presents unique difficulties with regard to keeping the cells alive, introducing fluorescent probes, and imaging through thick, hazy cytoplasm. This article outlines the major tissue types amenable to study by time-lapse cinematography and different methods for keeping the cells alive. It describes various imaging and associated techniques best suited to following changes in the distribution of fluorescently labeled molecules in real time in these tissues. Imaging, in general, is a rapidly developing discipline, and recent advances in imaging technology are able to greatly extend what can be achieved with live cell imaging of Drosophila tissues. As far as possible, this article includes the latest technical developments and discusses likely future developments in imaging methods that could have an impact on research using Drosophila.
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Keller PJ, Stelzer EHK. Digital scanned laser light sheet fluorescence microscopy. Cold Spring Harb Protoc 2010; 2010:pdb.top78. [PMID: 20439423 DOI: 10.1101/pdb.top78] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Modern applications in the life sciences are frequently based on in vivo imaging of biological specimens, a domain for which light microscopy approaches are typically best suited. Often, quantitative information must be obtained from large multicellular organisms on the cellular or even subcellular level and with a good temporal resolution. However, this usually requires a combination of conflicting features: high imaging speed, low photobleaching, and low phototoxicity in the specimen, good three-dimensional (3D) resolution, an excellent signal-to-noise ratio, and multiple-view imaging capability. The latter feature refers to the capability of recording a specimen along multiple directions, which is crucial for the imaging of large specimens with strong light-scattering or light-absorbing tissue properties. An imaging technique that fulfills these requirements is essential for many key applications: For example, studying fast cellular processes over long periods of time, imaging entire embryos throughout development, or reconstructing the formation of morphological defects in mutants. Here, we discuss digital scanned laser light sheet fluorescence microscopy (DSLM) as a novel tool for quantitative in vivo imaging in the post-genomic era and show how this emerging technique relates to the currently most widely applied 3D microscopy techniques in biology: confocal fluorescence microscopy and two-photon microscopy.
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Abstract
Dynamic instability, in which abrupt transitions occur between growing and shrinking states, is an intrinsic property of microtubules that is regulated by both mechanics and specialized proteins. We discuss a model of dynamic instability based on the popular idea that growth is maintained by a cap at the tip of the fiber. The loss of this cap is thought to trigger the transition from growth to shrinkage, called a catastrophe. The model includes longitudinal interactions between the terminal tubulins of each protofilament and "gating rescues" between neighboring protofilaments. These interactions allow individual protofilaments to transiently shorten during a phase of overall microtubule growth. The model reproduces the reported dependency of the catastrophe rate on tubulin concentration, the time between tubulin dilution and catastrophe, and the induction of microtubule catastrophes by walking depolymerases. The model also reproduces the comet tail distribution that is characteristic of proteins that bind to the tips of growing microtubules.
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Quantitative in vivo imaging of entire embryos with Digital Scanned Laser Light Sheet Fluorescence Microscopy. Curr Opin Neurobiol 2008; 18:624-32. [DOI: 10.1016/j.conb.2009.03.008] [Citation(s) in RCA: 125] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2008] [Revised: 02/23/2009] [Accepted: 03/23/2009] [Indexed: 11/22/2022]
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