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Huss-Hansen MK, Hedlund EG, Davydok A, Hansteen M, Overdijk J, de Cremer G, Roeffaers M, Knaapila M, Balzano L. Local structure mapping of gel-spun ultrahigh-molecular-weight polyethylene fibers. POLYMER 2022. [DOI: 10.1016/j.polymer.2021.124420] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Langenaeken NA, Ieven P, Hedlund EG, Kyomugasho C, van de Walle D, Dewettinck K, Van Loey AM, Roeffaers MBJ, Courtin CM. Arabinoxylan, β-glucan and pectin in barley and malt endosperm cell walls: a microstructure study using CLSM and cryo-SEM. Plant J 2020; 103:1477-1489. [PMID: 32412127 DOI: 10.1111/tpj.14816] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Revised: 04/29/2020] [Accepted: 05/05/2020] [Indexed: 05/14/2023]
Abstract
The architecture of endosperm cell walls in Hordeum vulgare (barley) differs remarkably from that of other grass species and is affected by germination or malting. Here, the cell wall microstructure is investigated using (bio)chemical analyses, cryogenic scanning electron microscopy (cryo-SEM) and confocal laser scanning microscopy (CLSM) as the main techniques. The relative proportions of β-glucan, arabinoxylan and pectin in cell walls were 61, 34 and 5%, respectively. The average thickness of a single endosperm cell wall was 0.30 µm, as estimated by the cryo-SEM analysis of barley seeds, which was reduced to 0.16 µm after malting. After fluorescent staining, 3D confocal multiphoton microscopy (multiphoton CLSM) imaging revealed the complex cell wall architecture. The endosperm cell wall is composed of a structure in which arabinoxylan and pectin are colocalized on the outside, with β-glucan depositions on the inside. During germination, arabinoxylan and β-glucan are hydrolysed, but unlike β-glucan, arabinoxylan remains present in defined cell walls in malt. Integrating the results, an enhanced model for the endosperm cell walls in barley is proposed.
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Affiliation(s)
- Niels A Langenaeken
- Laboratory of Food Chemistry and Biochemistry, Leuven Food Science and Nutrition Research Centre (LFoRCe), KU Leuven, Kasteelpark Arenberg 20, Leuven, 3001, Belgium
| | - Pieter Ieven
- Laboratory of Food Chemistry and Biochemistry, Leuven Food Science and Nutrition Research Centre (LFoRCe), KU Leuven, Kasteelpark Arenberg 20, Leuven, 3001, Belgium
| | - Erik G Hedlund
- Centre for Surface Chemistry and Catalysis, KU Leuven, Leuven, 3001, Belgium
| | - Clare Kyomugasho
- Laboratory of Food Technology, Leuven Food Science and Nutrition Research Center (LFoRCe), KU Leuven, Kasteelpark Arenberg 22, Heverlee, 3001, Belgium
| | - Davy van de Walle
- Laboratory of Food Technology and Engineering, Department of Food Technology, Safety and Health, Ghent University, Coupure Links 653, Ghent, 9000, Belgium
| | - Koen Dewettinck
- Laboratory of Food Technology and Engineering, Department of Food Technology, Safety and Health, Ghent University, Coupure Links 653, Ghent, 9000, Belgium
| | - Ann M Van Loey
- Laboratory of Food Technology, Leuven Food Science and Nutrition Research Center (LFoRCe), KU Leuven, Kasteelpark Arenberg 22, Heverlee, 3001, Belgium
| | | | - Christophe M Courtin
- Laboratory of Food Chemistry and Biochemistry, Leuven Food Science and Nutrition Research Centre (LFoRCe), KU Leuven, Kasteelpark Arenberg 20, Leuven, 3001, Belgium
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Wollman AJM, Hedlund EG, Shashkova S, Leake MC. Towards mapping the 3D genome through high speed single-molecule tracking of functional transcription factors in single living cells. Methods 2019; 170:82-89. [PMID: 31252059 PMCID: PMC6971689 DOI: 10.1016/j.ymeth.2019.06.021] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Accepted: 06/22/2019] [Indexed: 10/26/2022] Open
Abstract
How genomic DNA is organized in the nucleus is a long-standing question. We describe a single-molecule bioimaging method utilizing super-localization precision coupled to fully quantitative image analysis tools, towards determining snapshots of parts of the 3D genome architecture of model eukaryote budding yeast Saccharomyces cerevisiae with exceptional millisecond time resolution. We employ astigmatism imaging to enable robust extraction of 3D position data on genomically encoded fluorescent protein reporters that bind to DNA. Our relatively straightforward method enables snippets of 3D architectures of likely single genome conformations to be resolved captured via DNA-sequence specific binding proteins in single functional living cells.
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Affiliation(s)
- Adam J M Wollman
- Biological Physical Science Institute, Departments of Physics and Biology, University of York, YO10 5DD York, UK.
| | - Erik G Hedlund
- Biological Physical Science Institute, Departments of Physics and Biology, University of York, YO10 5DD York, UK.
| | - Sviatlana Shashkova
- Biological Physical Science Institute, Departments of Physics and Biology, University of York, YO10 5DD York, UK.
| | - Mark C Leake
- Biological Physical Science Institute, Departments of Physics and Biology, University of York, YO10 5DD York, UK.
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Wollman AJM, Shashkova S, Hedlund EG, Friemann R, Hohmann S, Leake MC. Correction: Transcription factor clusters regulate genes in eukaryotic cells. eLife 2019; 8:45804. [PMID: 30726187 PMCID: PMC6365053 DOI: 10.7554/elife.45804] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Wollman AJ, Shashkova S, Hedlund EG, Friemann R, Hohmann S, Leake MC. Transcription factor clusters regulate genes in eukaryotic cells. eLife 2017; 6:27451. [PMID: 28841133 PMCID: PMC5602325 DOI: 10.7554/elife.27451] [Citation(s) in RCA: 70] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Accepted: 08/24/2017] [Indexed: 01/07/2023] Open
Abstract
Transcription is regulated through binding factors to gene promoters to activate or repress expression, however, the mechanisms by which factors find targets remain unclear. Using single-molecule fluorescence microscopy, we determined in vivo stoichiometry and spatiotemporal dynamics of a GFP tagged repressor, Mig1, from a paradigm signaling pathway of Saccharomyces cerevisiae. We find the repressor operates in clusters, which upon extracellular signal detection, translocate from the cytoplasm, bind to nuclear targets and turnover. Simulations of Mig1 configuration within a 3D yeast genome model combined with a promoter-specific, fluorescent translation reporter confirmed clusters are the functional unit of gene regulation. In vitro and structural analysis on reconstituted Mig1 suggests that clusters are stabilized by depletion forces between intrinsically disordered sequences. We observed similar clusters of a co-regulatory activator from a different pathway, supporting a generalized cluster model for transcription factors that reduces promoter search times through intersegment transfer while stabilizing gene expression.
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Affiliation(s)
- Adam Jm Wollman
- Biological Physical Sciences Institute, University of York, York, United Kingdom
| | - Sviatlana Shashkova
- Biological Physical Sciences Institute, University of York, York, United Kingdom.,Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden
| | - Erik G Hedlund
- Biological Physical Sciences Institute, University of York, York, United Kingdom
| | - Rosmarie Friemann
- Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden
| | - Stefan Hohmann
- Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden.,Department of Biology and Biological Engineering, Chalmers University of Technology, Göteborg, Sweden
| | - Mark C Leake
- Biological Physical Sciences Institute, University of York, York, United Kingdom
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Wollman AJ, Shashkova S, Welkenhuysen N, Hedlund EG, Hohmann S, C. Leake M. Time-Resolved Single Cell, Sub-Cellular Compartmentalized Proteomics, Combining Precise Microfluidics, Deconvolution and Ultrasensitive Single-Molecule Microscopy. Biophys J 2017. [DOI: 10.1016/j.bpj.2016.11.1697] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Hedlund EG, Shashkova S, Wollman AJ, Hohmann S, Leake MC. Single-Molecule Transcription Factor Dynamics in Saccharomyces Cerevisiæ Glucose Sensing. Biophys J 2017. [DOI: 10.1016/j.bpj.2016.11.1528] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Hedlund EG, Shashkova S, Wollman AJ, Hohmann S, Leake MC. Real-Time 3D Imaging at the Single Molecule Level of Signal Transduction in Saccharomyces CerevisiÆ Responding to Environmental Changes. Biophys J 2016. [DOI: 10.1016/j.bpj.2015.11.823] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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Abstract
Although not laying claim to being the inventor of the light microscope, Antonj van Leeuwenhoek (1632–1723) was arguably the first person to bring this new technological wonder of the age properly to the attention of natural scientists interested in the study of living things (people we might now term ‘biologists’). He was a Dutch draper with no formal scientific training. From using magnifying glasses to observe threads in cloth, he went on to develop over 500 simple single lens microscopes (Baker & Leeuwenhoek 1739 Phil. Trans. 41, 503–519. (doi:10.1098/rstl.1739.0085)) which he used to observe many different biological samples. He communicated his finding to the Royal Society in a series of letters (Leeuwenhoek 1800 The select works of Antony Van Leeuwenhoek, containing his microscopical discoveries in many of the works of nature, vol. 1) including the one republished in this edition of Open Biology. Our review here begins with the work of van Leeuwenhoek before summarizing the key developments over the last ca 300 years, which has seen the light microscope evolve from a simple single lens device of van Leeuwenhoek's day into an instrument capable of observing the dynamics of single biological molecules inside living cells, and to tracking every cell nucleus in the development of whole embryos and plants.
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Affiliation(s)
- Adam J M Wollman
- Biological Physical Sciences Institute (BPSI), Departments of Physics and Biology, University of York, York YO10 5DD, UK
| | - Richard Nudd
- Biological Physical Sciences Institute (BPSI), Departments of Physics and Biology, University of York, York YO10 5DD, UK
| | - Erik G Hedlund
- Biological Physical Sciences Institute (BPSI), Departments of Physics and Biology, University of York, York YO10 5DD, UK
| | - Mark C Leake
- Biological Physical Sciences Institute (BPSI), Departments of Physics and Biology, University of York, York YO10 5DD, UK
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