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Gardeazabal Rodriguez PF, Lilach Y, Ambegaonkar A, Vitali T, Jafri H, Sohn HW, Dalva M, Pierce S, Chung I. MAxSIM: multi-angle-crossing structured illumination microscopy with height-controlled mirror for 3D topological mapping of live cells. Commun Biol 2023; 6:1034. [PMID: 37828050 PMCID: PMC10570291 DOI: 10.1038/s42003-023-05380-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Accepted: 09/21/2023] [Indexed: 10/14/2023] Open
Abstract
Mapping 3D plasma membrane topology in live cells can bring unprecedented insights into cell biology. Widefield-based super-resolution methods such as 3D-structured illumination microscopy (3D-SIM) can achieve twice the axial ( ~ 300 nm) and lateral ( ~ 100 nm) resolution of widefield microscopy in real time in live cells. However, twice-resolution enhancement cannot sufficiently visualize nanoscale fine structures of the plasma membrane. Axial interferometry methods including fluorescence light interference contrast microscopy and its derivatives (e.g., scanning angle interference microscopy) can determine nanoscale axial locations of proteins on and near the plasma membrane. Thus, by combining super-resolution lateral imaging of 2D-SIM with axial interferometry, we developed multi-angle-crossing structured illumination microscopy (MAxSIM) to generate multiple incident angles by fast, optoelectronic creation of diffraction patterns. Axial localization accuracy can be enhanced by placing cells on a bottom glass substrate, locating a custom height-controlled mirror (HCM) at a fixed axial position above the glass substrate, and optimizing the height reconstruction algorithm for noisy experimental data. The HCM also enables imaging of both the apical and basal surfaces of a cell. MAxSIM with HCM offers high-fidelity nanoscale 3D topological mapping of cell plasma membranes with near-real-time ( ~ 0.5 Hz) imaging of live cells and 3D single-molecule tracking.
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Affiliation(s)
| | - Yigal Lilach
- Nanofabrication and Imaging Center, George Washington University, Washington, DC, USA
| | - Abhijit Ambegaonkar
- Laboratory of Immunogenetics, National Institute of Allergy and Infectious Disease, National Institutes of Health, Rockville, MD, USA
| | - Teresa Vitali
- Department of Anatomy and Cell Biology, George Washington University, School of Medicine and Health Sciences, Washington, DC, USA
| | - Haani Jafri
- Department of Neuroscience, Thomas Jefferson University, Philadelphia, PA, USA
| | - Hae Won Sohn
- Laboratory of Immunogenetics, National Institute of Allergy and Infectious Disease, National Institutes of Health, Rockville, MD, USA
| | - Matthew Dalva
- Department of Neuroscience, Thomas Jefferson University, Philadelphia, PA, USA
- Department of Cell and Molecular Biology, Tulane University, New Orleans, LA, USA
| | - Susan Pierce
- Laboratory of Immunogenetics, National Institute of Allergy and Infectious Disease, National Institutes of Health, Rockville, MD, USA
| | - Inhee Chung
- Department of Anatomy and Cell Biology, George Washington University, School of Medicine and Health Sciences, Washington, DC, USA.
- Department of Biomedical Engineering, GW School of Engineering and Applied Science, George Washington University, Washington, DC, USA.
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2
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Hsiao YT, Tsai CN, Chen TH, Hsieh CL. Label-Free Dynamic Imaging of Chromatin in Live Cell Nuclei by High-Speed Scattering-Based Interference Microscopy. ACS Nano 2022; 16:2774-2788. [PMID: 34967599 DOI: 10.1021/acsnano.1c09748] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Chromatin is a DNA-protein complex that is densely packed in the cell nucleus. The nanoscale chromatin compaction plays critical roles in the modulation of cell nuclear processes. However, little is known about the spatiotemporal dynamics of chromatin compaction states because it remains difficult to quantitatively measure the chromatin compaction level in live cells. Here, we demonstrate a strategy, referenced as DYNAMICS imaging, for mapping chromatin organization in live cell nuclei by analyzing the dynamic scattering signal of molecular fluctuations. Highly sensitive optical interference microscopy, coherent brightfield (COBRI) microscopy, is implemented to detect the linear scattering of unlabeled chromatin at a high speed. A theoretical model is established to determine the local chromatin density from the statistical fluctuation of the measured scattering signal. DYNAMICS imaging allows us to reconstruct a speckle-free nucleus map that is highly correlated to the fluorescence chromatin image. Moreover, together with calibration based on nanoparticle colloids, we show that the DYNAMICS signal is sensitive to the chromatin compaction level at the nanoscale. We confirm the effectiveness of DYNAMICS imaging in detecting the condensation and decondensation of chromatin induced by chemical drug treatments. Importantly, the stable scattering signal supports a continuous observation of the chromatin condensation and decondensation processes for more than 1 h. Using this technique, we detect transient and nanoscopic chromatin condensation events occurring on a time scale of a few seconds. Label-free DYNAMICS imaging offers the opportunity to investigate chromatin conformational dynamics and to explore their significance in various gene activities.
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Affiliation(s)
- Yi-Teng Hsiao
- Institute of Atomic and Molecular Sciences (IAMS), Academia Sinica, 1 Roosevelt Road Section 4, Taipei 10617, Taiwan
| | - Chia-Ni Tsai
- Institute of Atomic and Molecular Sciences (IAMS), Academia Sinica, 1 Roosevelt Road Section 4, Taipei 10617, Taiwan
| | - Te-Hsin Chen
- Institute of Atomic and Molecular Sciences (IAMS), Academia Sinica, 1 Roosevelt Road Section 4, Taipei 10617, Taiwan
| | - Chia-Lung Hsieh
- Institute of Atomic and Molecular Sciences (IAMS), Academia Sinica, 1 Roosevelt Road Section 4, Taipei 10617, Taiwan
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3
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Colville M, Park S, Singh A, Paszek M, Zipfel WR. Azimuthal Beam Scanning Microscope Design and Implementation for Axial Localization with Scanning Angle Interference Microscopy. Methods Mol Biol 2022; 2393:127-152. [PMID: 34837177 DOI: 10.1007/978-1-0716-1803-5_7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Azimuthal beam scanning, also referred to as circle scanning, is an effective way of eliminating coherence artifacts with laser illumination in widefield microscopy. With a static excitation spot, dirt on the optics and internal reflections can produce an uneven excitation field due to interference fringes. These artifacts become more pronounced in TIRF microscopy, where the excitation is confined to an evanescent field that extends a few hundred nanometers above the coverslip. Unwanted intensity patterns that arise from these imperfections vary with path of the excitation beam through the microscope optical train, so by rapidly rotating the beam through its azimuth the uneven illumination is eliminated by averaging over the camera exposure time. In addition to being useful from TIRF microscopy, it is also critical for scanning angle interference microscopy (SAIM), an axial localization technique with nanometer-scale precision that requires similar instrumentation to TIRF microscopy. For robust SAIM localization, laser excitation with a homogeneous profile over a range of polar angles is required. We have applied the circle scanning principle to SAIM, constructing an optimized instrument configuration and open-source hardware, enabling high-precision localization and significantly higher temporal resolution than previous implementations. In this chapter, we detail the design and construction of the SAIM instrument, including the optical configuration, required peripheral devices, and system calibration.
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Affiliation(s)
| | - Sangwoo Park
- Graduate Field of Biophysics, Cornell University, Ithaca, NY, USA
| | - Avtar Singh
- Applied and Engineering Physics, Cornell University, Ithaca, NY, USA
- Broad Institute, Cambridge, MA, USA
| | - Matthew Paszek
- Graduate Field of Biophysics, Cornell University, Ithaca, NY, USA
- Robert Frederick Smith School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, NY, USA
- Field of Biomedical Engineering, Cornell University, Ithaca, NY, USA
- Kavli Institute for Nanoscale Science, Cornell University, Ithaca, NY, USA
| | - Warren R Zipfel
- Graduate Field of Biophysics, Cornell University, Ithaca, NY, USA.
- Applied and Engineering Physics, Cornell University, Ithaca, NY, USA.
- Kavli Institute for Nanoscale Science, Cornell University, Ithaca, NY, USA.
- Nancy E. and Peter C. Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY, USA.
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4
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VanDelinder V, Bachand GD. Characterizing the Number of Kinesin Motors Bound to Microtubules in the Gliding Motility Assay Using FLIC Microscopy. Methods Mol Biol 2022; 2430:93-104. [PMID: 35476327 DOI: 10.1007/978-1-0716-1983-4_6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Intracellular transport by kinesin motors moving along their associated cytoskeletal filaments, microtubules, is essential to many biological processes. This active transport system can be reconstituted in vitro with the surface-adhered motors transporting the microtubules across a planar surface. In this geometry, the kinesin-microtubule system has been used to study active self-assembly, to power microdevices, and to perform analyte detection. Fundamental to these applications is the ability to characterize the interactions between the surface tethered motors and microtubules. Fluorescence Interference Contrast (FLIC) microscopy can illuminate the height of the microtubule above a surface, which, at sufficiently low surface densities of kinesin, also reveals the number, locations, and dynamics of the bound motors.
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Affiliation(s)
- Virginia VanDelinder
- Center for Integrated Nanotechnologies, Sandia National Laboratories, Albuquerque, NM, Mexico
| | - George D Bachand
- Center for Integrated Nanotechnologies, Sandia National Laboratories, Albuquerque, NM, Mexico.
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5
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Dudaie M, Shinar S, Shaked NT. Polarization-independent differential interference contrast and off-axis holography combined module. Appl Opt 2021; 60:10825-10829. [PMID: 35200842 DOI: 10.1364/ao.442065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Accepted: 11/03/2021] [Indexed: 06/14/2023]
Abstract
We present an external portable module for transforming bright-field microscopy to differential interference contrast (DIC) microscopy and digital holographic microscopy together. The module is composed of simple optical elements, positioned between the microscope output plane and the digital camera plane; thus, it can be integrated externally with existing microscopes. The proposed module enables polarization DIC imaging, without special polarization elements, under either white-light or coherent illumination, providing label-free imaging of biological samples, as recorded directly by the digital camera. In addition, by rotating one element inside the module, an off-axis hologram is created on the camera under coherent illumination, thus providing the possibility for reconstruction of the quantitative phase profile of the same sample. The method is demonstrated for imaging silica microspheres and biological cells.
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6
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Bhatt S, Butola A, Kanade SR, Kumar A, Mehta DS. High-resolution single-shot phase-shifting interference microscopy using deep neural network for quantitative phase imaging of biological samples. J Biophotonics 2021; 14:e202000473. [PMID: 33913255 DOI: 10.1002/jbio.202000473] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [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: 11/28/2020] [Revised: 04/24/2021] [Accepted: 04/25/2021] [Indexed: 06/12/2023]
Abstract
White light phase-shifting interference microscopy (WL-PSIM) is a prominent technique for high-resolution quantitative phase imaging (QPI) of industrial and biological specimens. However, multiple interferograms with accurate phase-shifts are essentially required in WL-PSIM for measuring the accurate phase of the object. Here, we present single-shot phase-shifting interferometric techniques for accurate phase measurement using filtered white light (520±36 nm) phase-shifting interference microscopy (F-WL-PSIM) and deep neural network (DNN). The methods are incorporated by training the DNN to generate (a) four phase-shifted frames and (b) direct phase from a single interferogram. The training of network is performed on two different samples i.e., optical waveguide and MG63 osteosarcoma cells. Further, performance of F-WL-PSIM+DNN framework is validated by comparing the phase map extracted from network generated and experimentally recorded interferograms. The current approach can further strengthen QPI techniques for high-resolution phase recovery using a single frame for different biomedical applications.
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Affiliation(s)
- Sunil Bhatt
- Bio-photonics and Green-photonics Laboratory, Department of Physics, Indian Institute of Technology Delhi, New Delhi, India
| | - Ankit Butola
- Bio-photonics and Green-photonics Laboratory, Department of Physics, Indian Institute of Technology Delhi, New Delhi, India
| | - Sheetal Raosaheb Kanade
- Bio-photonics and Green-photonics Laboratory, Department of Physics, Indian Institute of Technology Delhi, New Delhi, India
| | - Anand Kumar
- Bio-photonics and Green-photonics Laboratory, Department of Physics, Indian Institute of Technology Delhi, New Delhi, India
| | - Dalip Singh Mehta
- Bio-photonics and Green-photonics Laboratory, Department of Physics, Indian Institute of Technology Delhi, New Delhi, India
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7
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Abstract
Homologous recombination (HR) is a highly conserved DNA repair pathway required for the accurate repair of DNA double-stranded breaks. DNA recombination is catalyzed by the RecA/Rad51 family of proteins, which are conserved from bacteria to humans. The key intermediate catalyzing DNA recombination is the presynaptic complex (PSC), which is a helical filament comprised of Rad51-bound single-stranded DNA (ssDNA). Multiple cellular factors either promote or downregulate PSC activity, and a fine balance between such regulators is required for the proper regulation of HR and maintenance of genomic integrity. However, dissecting the complex mechanisms regulating PSC activity has been a challenge using traditional ensemble methods due to the transient and dynamic nature of recombination intermediates. We have developed a single-molecule assay called ssDNA curtains that allows us to visualize individual DNA intermediates in real-time, using total internal reflection microscopy (TIRFM). This assay has allowed us to study many aspects of HR regulation that involve complex and heterogenous reaction intermediates. Here we describe the procedure for a basic ssDNA curtain assay to study PSC filament dynamics, and explain how to process and analyze the resulting data.
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Affiliation(s)
- Upasana Roy
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY, USA
| | - Eric C Greene
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY, USA.
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8
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Park JS, Lee IB, Moon HM, Ryu JS, Kong SY, Hong SC, Cho M. Fluorescence-Combined Interferometric Scattering Imaging Reveals Nanoscale Dynamic Events of Single Nascent Adhesions in Living Cells. J Phys Chem Lett 2020; 11:10233-10241. [PMID: 33206530 DOI: 10.1021/acs.jpclett.0c02103] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Focal adhesions (FAs) are dynamic protein nanostructures that form mechanical links between cytoskeletal actin fibers and the extracellular matrix. Here, we demonstrate that interferometric scattering (iSCAT) microscopy, a high-speed and time-unlimited imaging technique, can uncover the real-time dynamics of nanoscopic nascent adhesions (NAs). The high sensitivity and stability of the iSCAT signal enabled us to trace the whole life span of each NA spontaneously nucleated under a lamellipodium. Such high-throughput and long-term image data provide a unique opportunity for statistical analysis of adhesion dynamics. Moreover, we directly revealed that FAs play critical roles in both the extrusion of filopodia as nucleation sites on the leading edge and the one-dimensional transport of cargos along cytoskeletal fibers as fiber docking sites. These experimental results show that iSCAT is a sensitive tool for tracking real-time dynamics of nanoscopic objects involved in endogenous and exogenous biological processes in living cells.
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Affiliation(s)
- Jin-Sung Park
- Center for Molecular Spectroscopy and Dynamics, Institute for Basic Science, Seoul 02841, Korea
| | - Il-Buem Lee
- Center for Molecular Spectroscopy and Dynamics, Institute for Basic Science, Seoul 02841, Korea
| | - Hyeon-Min Moon
- Center for Molecular Spectroscopy and Dynamics, Institute for Basic Science, Seoul 02841, Korea
| | - Jin-Sun Ryu
- Center for Breast Cancer, National Cancer Center, Goyang 10408, Korea
| | - Sun-Young Kong
- Division of Translational Science, National Cancer Center, Goyang 10408, Korea
| | - Seok-Cheol Hong
- Center for Molecular Spectroscopy and Dynamics, Institute for Basic Science, Seoul 02841, Korea
- Department of Physics, Korea University, Seoul 02841, Korea
| | - Minhaeng Cho
- Center for Molecular Spectroscopy and Dynamics, Institute for Basic Science, Seoul 02841, Korea
- Department of Chemistry, Korea University, Seoul 02841, Korea
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9
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Takano W, Shibata S, Hagen N, Matsuda M, Otani Y. Minimizing scattering-induced phase errors in differential interference contrast microscopy. J Biomed Opt 2020; 25:JBO-200280SSRR. [PMID: 33319525 PMCID: PMC7734411 DOI: 10.1117/1.jbo.25.12.123703] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Accepted: 10/26/2020] [Indexed: 06/12/2023]
Abstract
SIGNIFICANCE Differential interference contrast (DIC) microscopes allow noninvasive in vivo observation of transparent microstructures in tissue without the use of fluorescent dyes or genetic modification. We show how to modify a DIC microscope to measure the sample phase distribution accurately and in real-time even deep inside sample tissue. AIM Our aim is to improve the DIC microscope's phase measurement to remove the phase bias that occurs in the presence of strong scattering. APPROACH A quarter-wave plate was added in front of the polarization camera, allowing a modified phase calculation to incorporate all four polarization orientation angles (0 deg, 45 deg, 90 deg, and 135 deg) captured simultaneously by the polarization camera, followed by deconvolution. RESULTS We confirm that the proposed method reduces phase measurement error in the presence of scattering and demonstrate the method using in vivo imaging of a beating heart inside a medaka egg and the whole-body blood circulation in a young medaka fish. CONCLUSIONS Modifying a polarization-camera DIC microscope with a quarter-wave plate allows users to image deep inside samples without phase bias due to scattering effects.
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Affiliation(s)
- Wataru Takano
- Utsunomiya University, Department of Optical Engineering, Tochigi, Japan
- Utsunomiya University, Center for Optical Research and Education, Tochigi, Japan
| | - Shuhei Shibata
- Utsunomiya University, Center for Industry-University Innovation Support, Tochigi, Japan
| | - Nathan Hagen
- Utsunomiya University, Department of Optical Engineering, Tochigi, Japan
- Utsunomiya University, Center for Optical Research and Education, Tochigi, Japan
| | - Masaru Matsuda
- Utsunomiya University, Center for Bioscience Research and Education, Tochigi, Japan
| | - Yukitoshi Otani
- Utsunomiya University, Department of Optical Engineering, Tochigi, Japan
- Utsunomiya University, Center for Optical Research and Education, Tochigi, Japan
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10
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Locke A, Fitzgerald S, Mahadevan-Jansen A. Advances in Optical Detection of Human-Associated Pathogenic Bacteria. Molecules 2020; 25:E5256. [PMID: 33187331 PMCID: PMC7696695 DOI: 10.3390/molecules25225256] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2020] [Revised: 11/04/2020] [Accepted: 11/06/2020] [Indexed: 02/06/2023] Open
Abstract
Bacterial infection is a global burden that results in numerous hospital visits and deaths annually. The rise of multi-drug resistant bacteria has dramatically increased this burden. Therefore, there is a clinical need to detect and identify bacteria rapidly and accurately in their native state or a culture-free environment. Current diagnostic techniques lack speed and effectiveness in detecting bacteria that are culture-negative, as well as options for in vivo detection. The optical detection of bacteria offers the potential to overcome these obstacles by providing various platforms that can detect bacteria rapidly, with minimum sample preparation, and, in some cases, culture-free directly from patient fluids or even in vivo. These modalities include infrared, Raman, and fluorescence spectroscopy, along with optical coherence tomography, interference, polarization, and laser speckle. However, these techniques are not without their own set of limitations. This review summarizes the strengths and weaknesses of utilizing each of these optical tools for rapid bacteria detection and identification.
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Affiliation(s)
- Andrea Locke
- Vanderbilt Biophotonics Center, Nashville, TN 37232, USA; (A.L.); (S.F.)
- Department of Biomedical Engineering, Vanderbilt University, Nashville, TN 37232, USA
| | - Sean Fitzgerald
- Vanderbilt Biophotonics Center, Nashville, TN 37232, USA; (A.L.); (S.F.)
- Department of Biomedical Engineering, Vanderbilt University, Nashville, TN 37232, USA
| | - Anita Mahadevan-Jansen
- Vanderbilt Biophotonics Center, Nashville, TN 37232, USA; (A.L.); (S.F.)
- Department of Biomedical Engineering, Vanderbilt University, Nashville, TN 37232, USA
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11
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Llinares J, Cantereau A, Froux L, Becq F. Quantitative phase imaging to study transmembrane water fluxes regulated by CFTR and AQP3 in living human airway epithelial CFBE cells and CHO cells. PLoS One 2020; 15:e0233439. [PMID: 32469934 PMCID: PMC7259668 DOI: 10.1371/journal.pone.0233439] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Accepted: 05/05/2020] [Indexed: 11/22/2022] Open
Abstract
In epithelial cells, the cystic fibrosis transmembrane conductance regulator (CFTR), a cAMP-regulated Cl- channel, plays a key role in water and electrolytes secretion. A dysfunctional CFTR leads to the dehydration of the external environment of the cells and to the production of viscous mucus in the airways of cystic fibrosis patients. Here, we applied the quadriwave lateral shearing interferometry (QWLSI), a quantitative phase imaging technique based on the measurement of the light wave shift when passing through a living sample, to study water transport regulation in human airway epithelial CFBE and CHO cells expressing wild-type, G551D- and F508del-CFTR. We were able to detect phase variations during osmotic challenges and confirmed that cellular volume changes reflecting water fluxes can be detected with QWLSI. Forskolin stimulation activated a phase increase in all CFBE and CHO cell types. This phase variation was due to cellular volume decrease and intracellular refractive index increase and was completely blocked by mercury, suggesting an activation of a cAMP-dependent water efflux mediated by an endogenous aquaporin (AQP). AQP3 mRNAs, not AQP1, AQP4 and AQP5 mRNAs, were detected by RT-PCR in CFBE cells. Readdressing the F508del-CFTR protein to the cell surface with VX-809 increased the detected water efflux in CHO but not in CFBE cells. However, VX-770, a potentiator of CFTR function, failed to further increase the water flux in either G551D-CFTR or VX-809-corrected F508del-CFTR expressing cells. Our results show that QWLSI could be a suitable technique to study water transport in living cells. We identified a CFTR and cAMP-dependent, mercury-sensitive water transport in airway epithelial and CHO cells that might be due to AQP3. This water transport appears to be affected when CFTR is mutated and independent of the chloride channel function of CFTR.
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Affiliation(s)
- Jodie Llinares
- Laboratoire Signalisation et Transports Ioniques Membranaires, Université de Poitiers, Poitiers, France
| | - Anne Cantereau
- Laboratoire Signalisation et Transports Ioniques Membranaires, Université de Poitiers, Poitiers, France
| | - Lionel Froux
- Laboratoire Signalisation et Transports Ioniques Membranaires, Université de Poitiers, Poitiers, France
| | - Frédéric Becq
- Laboratoire Signalisation et Transports Ioniques Membranaires, Université de Poitiers, Poitiers, France
- * E-mail:
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12
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Yurdakul C, Avci O, Matlock A, Devaux AJ, Quintero MV, Ozbay E, Davey RA, Connor JH, Karl WC, Tian L, Ünlü MS. High-Throughput, High-Resolution Interferometric Light Microscopy of Biological Nanoparticles. ACS Nano 2020; 14:2002-2013. [PMID: 32003974 DOI: 10.1021/acsnano.9b08512] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Label-free, visible light microscopy is an indispensable tool for studying biological nanoparticles (BNPs). However, conventional imaging techniques have two major challenges: (i) weak contrast due to low-refractive-index difference with the surrounding medium and exceptionally small size and (ii) limited spatial resolution. Advances in interferometric microscopy have overcome the weak contrast limitation and enabled direct detection of BNPs, yet lateral resolution remains as a challenge in studying BNP morphology. Here, we introduce a wide-field interferometric microscopy technique augmented by computational imaging to demonstrate a 2-fold lateral resolution improvement over a large field-of-view (>100 × 100 μm2), enabling simultaneous imaging of more than 104 BNPs at a resolution of ∼150 nm without any labels or sample preparation. We present a rigorous vectorial-optics-based forward model establishing the relationship between the intensity images captured under partially coherent asymmetric illumination and the complex permittivity distribution of nanoparticles. We demonstrate high-throughput morphological visualization of a diverse population of Ebola virus-like particles and a structurally distinct Ebola vaccine candidate. Our approach offers a low-cost and robust label-free imaging platform for high-throughput and high-resolution characterization of a broad size range of BNPs.
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Affiliation(s)
- Celalettin Yurdakul
- Department of Electrical and Computer Engineering , Boston University , Boston , Massachusetts 02215 , United States
| | - Oguzhan Avci
- Department of Electrical and Computer Engineering , Boston University , Boston , Massachusetts 02215 , United States
| | - Alex Matlock
- Department of Electrical and Computer Engineering , Boston University , Boston , Massachusetts 02215 , United States
| | - Alexander J Devaux
- Department of Microbiology and National Infectious Diseases Laboratories , Boston University School of Medicine , Boston , Massachusetts 02118 , United States
| | - Maritza V Quintero
- Department of Biochemistry and Structural Biology , University of Texas Health San Antonio , San Antonio , Texas 78229 , United States
| | - Ekmel Ozbay
- Department of Electrical and Electronics Engineering , Bilkent University , 06800 Ankara , Turkey
| | - Robert A Davey
- Department of Microbiology and National Infectious Diseases Laboratories , Boston University School of Medicine , Boston , Massachusetts 02118 , United States
| | - John H Connor
- Department of Microbiology and National Infectious Diseases Laboratories , Boston University School of Medicine , Boston , Massachusetts 02118 , United States
| | - W Clem Karl
- Department of Electrical and Computer Engineering , Boston University , Boston , Massachusetts 02215 , United States
| | - Lei Tian
- Department of Electrical and Computer Engineering , Boston University , Boston , Massachusetts 02215 , United States
| | - M Selim Ünlü
- Department of Electrical and Computer Engineering , Boston University , Boston , Massachusetts 02215 , United States
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13
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Bhowmik D, Culver KSB, Liu T, Odom TW. Resolving Single-Nanoconstruct Dynamics during Targeting and Nontargeting Live-Cell Membrane Interactions. ACS Nano 2019; 13:13637-13644. [PMID: 31398007 PMCID: PMC7830831 DOI: 10.1021/acsnano.9b03144] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
This paper describes how differences in the dynamics of targeting and nontargeting constructs can provide information on nanoparticle (NP)-cell interactions. We probed translational and rotational dynamics of functionalized Au nanostar (AuNS) nanoconstructs interacting with cells in serum-containing medium. We found that AuNS with targeting ligands had a larger dynamical footprint and faster rotational speed on cell membranes expressing human epidermal growth factor receptor 2 (HER-2) receptors compared to that of AuNS with nontargeting ligands. Targeting and nontargeting nanoconstructs displayed distinct membrane dynamics despite their similar protein adsorption profiles, which suggests that targeted interactions are preserved even in the presence of a protein corona. The high sensitivity of single-NP dynamics can be used to compare different nanoconstruct properties (such as NP size, shape, and surface chemistry) to improve their design as delivery vehicles.
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Affiliation(s)
- Debanjan Bhowmik
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
| | - Kayla S. B. Culver
- Department of Materials Science & Engineering, Northwestern University, Evanston, Illinois 60208, United States
| | - Tingting Liu
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
| | - Teri W. Odom
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
- Department of Materials Science & Engineering, Northwestern University, Evanston, Illinois 60208, United States
- Corresponding Author: Phone: +1 (847) 491-7674.
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14
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Abstract
Drug delivery with nanocarriers relies on the interaction of individual nanocarriers with the cell surface. For lipid-based NCs, this interaction uniquely involves a process of membrane fusion between the lipid bilayer that makes up the NC and the cell membrane. Cubosomes have emerged as promising fusogenic NCs, however their individual interactions had not yet been directly observed due to difficulties in achieving adequate resolution or disentangling multiple interactions with common characterization techniques. Moreover, many studies on these interactions have been performed under static conditions which may not mimic the actual transport of NCs. Herein we have observed fusion of lipid cubosome NCs with lipid bilayers under flow. Total internal reflection microscopy has allowed visualisation of the fusion event which was sensitive to the lipid compositions and rationalized by lipid diffusion. The fusion event in supported lipid bilayers has been compared with those in cells, revealing a distinct similarity in kinetics.
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Affiliation(s)
- Brendan P Dyett
- School of Science, College of Science, Engineering and Health, RMIT University, Melbourne, Victoria, Australia
| | - Haitao Yu
- School of Science, College of Science, Engineering and Health, RMIT University, Melbourne, Victoria, Australia
| | - Jamie Strachan
- School of Science, College of Science, Engineering and Health, RMIT University, Melbourne, Victoria, Australia
| | - Calum J Drummond
- School of Science, College of Science, Engineering and Health, RMIT University, Melbourne, Victoria, Australia.
| | - Charlotte E Conn
- School of Science, College of Science, Engineering and Health, RMIT University, Melbourne, Victoria, Australia.
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15
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Wong NA, Uchida NV, Dissanayake TU, Patel M, Iqbal M, Woehl TJ. Detection and Sizing of Submicron Particles in Biologics With Interferometric Scattering Microscopy. J Pharm Sci 2019; 109:881-890. [PMID: 31160046 DOI: 10.1016/j.xphs.2019.05.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Revised: 04/17/2019] [Accepted: 05/07/2019] [Indexed: 12/14/2022]
Abstract
We demonstrate the application of interferometric scattering microscopy (IFS) for characterizing submicron particles in stir-stressed monoclonal antibody. IFS uses a layered silicon sensor and modified optical microscope to rapidly visualize and determine the particle size distribution (PSD) of submicron particles based on their scattering intensity, which is directly proportional to particle mass. Limits for particle size and optimal solution concentration were established for IFS characterization of submicron particles. We critically compare IFS data with dynamic light scattering (DLS) and nanoparticle tracking analysis (NTA) and find IFS is superior to NTA and DLS for determining the realistic shape of the number-based PSD, whereas NTA and DLS provide superior information about absolute particle size. Together, IFS, NTA, and DLS provide complementary information on submicron particles and enable quantitative characterization of the PSD of submicron aggregates. Finally, we explore quantifying particle size with IFS by developing a calibration curve for particle scattering intensity based on correlative scanning electron microscopy imaging. We found that only a subset of isotropic-shaped particles followed the expected proportionality between IFS intensity and particle mass. Overall, this study demonstrates IFS is a simple approach for detecting and quantifying submicron aggregate PSD in protein-based therapeutics.
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Affiliation(s)
- Nathan A Wong
- Department of Chemical and Biomolecular Engineering, University of Maryland, College Park, College Park, Maryland 20742
| | - Nina V Uchida
- Department of Chemical and Biomolecular Engineering, University of Maryland, College Park, College Park, Maryland 20742
| | - Thilini U Dissanayake
- Department of Chemical and Biomolecular Engineering, University of Maryland, College Park, College Park, Maryland 20742
| | - Mehulkumar Patel
- Division of Biology, Chemistry and Materials Science, Office of Science and Engineering Laboratories, Center for Devices and Radiological Health, U.S. Food and Drug Administration, Silver Spring, Maryland 20993
| | - Maira Iqbal
- Department of Chemical and Biomolecular Engineering, University of Maryland, College Park, College Park, Maryland 20742
| | - Taylor J Woehl
- Department of Chemical and Biomolecular Engineering, University of Maryland, College Park, College Park, Maryland 20742.
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16
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Dubey V, Ahmad A, Butola A, Qaiser D, Srivastava A, Mehta DS. Low coherence quantitative phase microscopy with machine learning model and Raman spectroscopy for the study of breast cancer cells and their classification. Appl Opt 2019; 58:A112-A119. [PMID: 30873967 DOI: 10.1364/ao.58.00a112] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Accepted: 11/19/2018] [Indexed: 06/09/2023]
Abstract
Early-stage detection of breast cancer is the primary requirement in modern healthcare as it is the most common cancer among women worldwide. Histopathology is the most widely preferred method for the diagnosis of breast cancer, but it requires long processing time and involves qualitative assessment of cancer by a trained person/doctor. Here, we present an alternate technique based on white light interference microscopy (WLIM) and Raman spectroscopy, which has the capability to differentiate between cancerous and normal breast tissue. WLIM provides quantitative phase information about the biological tissues/cells, whereas Raman spectroscopy can detect changes in their molecular structure and chemical composition during cancer growth. Further, both the techniques can be implemented very quickly without staining the sample. The present technique is employed to perform ex vivo study on a total of 80 normal and cancerous tissue samples collected from 16 different patients. A generalized machine learning model is developed for the classification of normal and cancerous tissues, which is based on texture features obtained from phase maps with an accuracy of 90.6%. The correlation of outcomes from these two techniques can open a new avenue for fast and accurate detection of cancer without any trained personnel.
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17
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Criado Santos N, Chehab T, Holthenrich A, Gerke V. Analysis of Ca 2+-Dependent Weibel-Palade Body Tethering by Live Cell TIRF Microscopy: Involvement of a Munc13-4/S100A10/Annexin A2 Complex. Methods Mol Biol 2019; 1929:437-445. [PMID: 30710289 DOI: 10.1007/978-1-4939-9030-6_27] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Endothelial cells respond to blood vessel injury by the acute release of the procoagulant von Willebrand factor, which is stored in unique secretory granules called Weibel-Palade bodies (WPBs). Stimulated, Ca2+-dependent exocytosis of WPBs critically depends on their proper targeting to the plasma membrane, but the mechanism of WPB-plasma membrane tethering prior to fusion is not well characterized. Here we describe a method to visualize and analyze WPB tethering and fusion in living human umbilical vein endothelial cells (HUVEC) by total internal reflection fluorescence (TIRF) microscopy. This method is based on automated object detection and allowed us to identify components of the tethering complex of WPBs and to monitor their dynamics in space and time. An important tethering factor identified by this means was Munc13-4 that was shown to interact with S100A10 residing in a complex with plasma membrane-bound annexin A2.
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Affiliation(s)
- Nina Criado Santos
- Centre for Molecular Biology of Inflammation, Institute of Medical Biochemistry, University of Münster, Münster, Germany
- Department of Cell Physiology and Metabolism, University of Geneva, Geneva, Switzerland
| | - Tarek Chehab
- Centre for Molecular Biology of Inflammation, Institute of Medical Biochemistry, University of Münster, Münster, Germany
| | - Anna Holthenrich
- Centre for Molecular Biology of Inflammation, Institute of Medical Biochemistry, University of Münster, Münster, Germany
| | - Volker Gerke
- Centre for Molecular Biology of Inflammation, Institute of Medical Biochemistry, University of Münster, Münster, Germany.
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18
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Kotak J, Saisana M, Gegas V, Pechlivani N, Kaldis A, Papoutsoglou P, Makris A, Burns J, Kendig AL, Sheikh M, Kuschner CE, Whitney G, Caiola H, Doonan JH, Vlachonasios KE, McCain ER, Hark AT. The histone acetyltransferase GCN5 and the transcriptional coactivator ADA2b affect leaf development and trichome morphogenesis in Arabidopsis. Planta 2018; 248:613-628. [PMID: 29846775 DOI: 10.1007/s00425-018-2923-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [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: 03/02/2018] [Accepted: 05/23/2018] [Indexed: 06/08/2023]
Abstract
The histone acetyltransferase GCN5 and associated transcriptional coactivator ADA2b are required to couple endoreduplication and trichome branching. Mutation of ADA2b also disrupts the relationship between ploidy and leaf cell size. Dynamic chromatin structure has been established as a general mechanism by which gene function is temporally and spatially regulated, but specific chromatin modifier function is less well understood. To address this question, we have investigated the role of the histone acetyltransferase GCN5 and the associated coactivator ADA2b in developmental events in Arabidopsis thaliana. Arabidopsis plants with T-DNA insertions in GCN5 (also known as HAG1) or ADA2b (also known as PROPORZ1) display pleiotropic phenotypes including dwarfism and floral defects affecting fertility. We undertook a detailed characterization of gcn5 and ada2b phenotypic effects in rosette leaves and trichomes to establish a role for epigenetic control in these developmental processes. ADA2b and GCN5 play specific roles in leaf tissue, affecting cell growth and division in rosette leaves often in complex and even opposite directions. Leaves of gcn5 plants display overall reduced ploidy levels, while ada2b-1 leaves show increased ploidy. Endoreduplication leading to increased ploidy is also known to contribute to normal trichome morphogenesis. We demonstrate that gcn5 and ada2b mutants display alterations in the number and patterning of trichome branches, with ada2b-1 and gcn5-1 trichomes being significantly less branched, while gcn5-6 trichomes show increased branching. Elongation of the trichome stalk and branches also vary in different mutant backgrounds, with stalk length having an inverse relationship with branch number. Taken together, our data indicate that, in Arabidopsis, leaves and trichomes ADA2b and GCN5 are required to couple nuclear content with cell growth and morphogenesis.
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Affiliation(s)
- Jenna Kotak
- Biology Department, Muhlenberg College, Allentown, PA, USA
- Molecular Biology, Cell Biology, and Biochemistry Department, Brown University, Providence, RI, USA
| | - Marina Saisana
- Department of Botany, School of Biology, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Vasilis Gegas
- National Plant Phenomics Centre, Aberystwyth University, Aberystwyth, UK
- Limagrain UK Ltd, Joseph Nickerson Research Centre, Rothwell, Market Rasen, Lincolnshire, UK
| | - Nikoletta Pechlivani
- Department of Botany, School of Biology, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Athanasios Kaldis
- Department of Botany, School of Biology, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Panagiotis Papoutsoglou
- Department of Botany, School of Biology, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Athanasios Makris
- Department of Botany, School of Biology, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Julia Burns
- Biology Department, Muhlenberg College, Allentown, PA, USA
| | | | - Minnah Sheikh
- Biology Department, Muhlenberg College, Allentown, PA, USA
| | | | | | - Hanna Caiola
- Biology Department, Muhlenberg College, Allentown, PA, USA
| | - John H Doonan
- National Plant Phenomics Centre, Aberystwyth University, Aberystwyth, UK
| | | | | | - Amy T Hark
- Biology Department, Muhlenberg College, Allentown, PA, USA.
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19
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Vora P, Trivedi V, Mahajan S, Patel N, Joglekar M, Chhaniwal V, Moradi AR, Javidi B, Anand A. Wide field of view common-path lateral-shearing digital holographic interference microscope. J Biomed Opt 2017; 22:1-11. [PMID: 29235271 DOI: 10.1117/1.jbo.22.12.126001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [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: 08/16/2017] [Accepted: 11/16/2017] [Indexed: 05/12/2023]
Abstract
Quantitative three-dimensional (3-D) imaging of living cells provides important information about the cell morphology and its time variation. Off-axis, digital holographic interference microscopy is an ideal tool for 3-D imaging, parameter extraction, and classification of living cells. Two-beam digital holographic microscopes, which are usually employed, provide high-quality 3-D images of micro-objects, albeit with lower temporal stability. Common-path digital holographic geometries, in which the reference beam is derived from the object beam, provide higher temporal stability along with high-quality 3-D images. Self-referencing geometry is the simplest of the common-path techniques, in which a portion of the object beam itself acts as the reference, leading to compact setups using fewer optical elements. However, it has reduced field of view, and the reference may contain object information. Here, we describe the development of a common-path digital holographic microscope, employing a shearing plate and converting one of the beams into a separate reference by employing a pin-hole. The setup is as compact as self-referencing geometry, while providing field of view as wide as that of a two-beam microscope. The microscope is tested by imaging and quantifying the morphology and dynamics of human erythrocytes.
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Affiliation(s)
- Priyanka Vora
- The Maharaja Sayajirao University of Baroda, Faculty of Technology and Engineering, Department of Ap, India
- Uka Tarsadia University, Department of Physics, Bardoli, Gujarat, India
| | - Vismay Trivedi
- The Maharaja Sayajirao University of Baroda, Faculty of Technology and Engineering, Department of Ap, India
| | - Swapnil Mahajan
- The Maharaja Sayajirao University of Baroda, Faculty of Technology and Engineering, Department of Ap, India
| | - Nimit Patel
- The Maharaja Sayajirao University of Baroda, Faculty of Technology and Engineering, Department of Ap, India
| | - Mugdha Joglekar
- The Maharaja Sayajirao University of Baroda, Faculty of Technology and Engineering, Department of Ap, India
| | - Vani Chhaniwal
- The Maharaja Sayajirao University of Baroda, Faculty of Technology and Engineering, Department of Ap, India
| | - Ali-Reza Moradi
- Institute for Research in Fundamental Sciences, School of Nano Science, Tehran, Iran
- Institute for Advanced Studies in Basic Sciences, Optics Research Center, Zanjan, Iran
| | - Bahram Javidi
- University of Connecticut, Department of Electrical and Computer Engineering, Storrs, Connecticut, United States
| | - Arun Anand
- The Maharaja Sayajirao University of Baroda, Faculty of Technology and Engineering, Department of Ap, India
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20
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Plante S, Normant V, Ramos-Torres KM, Labbé S. Cell-surface copper transporters and superoxide dismutase 1 are essential for outgrowth during fungal spore germination. J Biol Chem 2017; 292:11896-11914. [PMID: 28572514 PMCID: PMC5512082 DOI: 10.1074/jbc.m117.794677] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Revised: 05/26/2017] [Indexed: 11/06/2022] Open
Abstract
During fungal spore germination, a resting spore returns to a conventional mode of cell division and resumes vegetative growth, but the requirements for spore germination are incompletely understood. Here, we show that copper is essential for spore germination in Schizosaccharomyces pombe Germinating spores develop a single germ tube that emerges from the outer spore wall in a process called outgrowth. Under low-copper conditions, the copper transporters Ctr4 and Ctr5 are maximally expressed at the onset of outgrowth. In the case of Ctr6, its expression is broader, taking place before and during outgrowth. Spores lacking Ctr4, Ctr5, and the copper sensor Cuf1 exhibit complete germination arrest at outgrowth. In contrast, ctr6 deletion only partially interferes with formation of outgrowing spores. At outgrowth, Ctr4-GFP and Ctr5-Cherry first co-localize at the spore contour, followed by re-location to a middle peripheral spore region. Subsequently, they move away from the spore body to occupy the periphery of the nascent cell. After breaking of spore dormancy, Ctr6 localizes to the vacuole membranes that are enriched in the spore body relative to the germ tube. Using a copper-binding tracker, results showed that labile copper is preferentially localized to the spore body. Further analysis showed that Ctr4 and Ctr6 are required for copper-dependent activation of the superoxide dismutase 1 (SOD1) during spore germination. This activation is critical because the loss of SOD1 activity blocked spore germination at outgrowth. Taken together, these results indicate that cell-surface copper transporters and SOD1 are required for completion of the spore germination program.
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MESH Headings
- Cation Transport Proteins/genetics
- Cation Transport Proteins/metabolism
- Copper/metabolism
- Enzyme Activation
- Gene Deletion
- Gene Expression Regulation, Fungal
- Green Fluorescent Proteins/genetics
- Green Fluorescent Proteins/metabolism
- Luminescent Proteins/genetics
- Luminescent Proteins/metabolism
- Microscopy, Fluorescence
- Microscopy, Interference
- Microscopy, Phase-Contrast
- Protein Isoforms/genetics
- Protein Isoforms/metabolism
- Protein Transport
- RNA, Fungal/metabolism
- RNA, Messenger/metabolism
- Recombinant Fusion Proteins/genetics
- Recombinant Fusion Proteins/metabolism
- SLC31 Proteins
- Schizosaccharomyces/cytology
- Schizosaccharomyces/growth & development
- Schizosaccharomyces/metabolism
- Schizosaccharomyces/physiology
- Schizosaccharomyces pombe Proteins/genetics
- Schizosaccharomyces pombe Proteins/metabolism
- Spores, Fungal/cytology
- Spores, Fungal/growth & development
- Spores, Fungal/metabolism
- Spores, Fungal/physiology
- Superoxide Dismutase-1/metabolism
- Transcription Factors/genetics
- Transcription Factors/metabolism
- Red Fluorescent Protein
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Affiliation(s)
- Samuel Plante
- Département de Biochimie, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, Quebec J1E 4K8, Canada
| | - Vincent Normant
- Département de Biochimie, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, Quebec J1E 4K8, Canada
| | - Karla M Ramos-Torres
- Department of Chemistry, University of California at Berkeley, Berkeley, California 94720
| | - Simon Labbé
- Département de Biochimie, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, Quebec J1E 4K8, Canada.
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21
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Choi H, Broitman-Maduro G, Maduro MF. Partially compromised specification causes stochastic effects on gut development in C. elegans. Dev Biol 2017; 427:49-60. [PMID: 28502614 DOI: 10.1016/j.ydbio.2017.05.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2017] [Revised: 04/26/2017] [Accepted: 05/08/2017] [Indexed: 12/29/2022]
Abstract
The C. elegans gut descends from the E progenitor cell through a series of stereotyped cell divisions and morphogenetic events. Effects of perturbations of upstream cell specification on downstream organogenesis have not been extensively investigated. Here we have assembled an allelic series of strains that variably compromise specification of E by perturbing the activation of the gut-specifying end-1 and end-3 genes. Using a marker that allows identification of all E descendants regardless of fate, superimposed with markers that identify cells that have adopted a gut fate, we have examined the fate of E lineage descendants among hundreds of embryos. We find that when specification is partially compromised, the E lineage undergoes hyperplasia accompanied by stochastic and variable specification of gut fate among the E descendants. As anticipated by prior work, the activation of the gut differentiation factor elt-2 becomes delayed in these strains, although ultimate protein levels of a translational ELT-2::GFP reporter resemble those of the wild type. By comparing these effects among the various specification mutants, we find that the stronger the defect in specification (i.e. the fewer number of embryos specifying gut), the stronger the defects in the E lineage and delay in activation of elt-2. Despite the changes in the E lineage in these strains, we find that supernumerary E descendants that adopt a gut fate are accommodated into a relatively normal-looking intestine. Hence, upstream perturbation of specification dramatically affects the E lineage, but as long as sufficient descendants adopt a gut fate, organogenesis overcomes these effects to form a relatively normal intestine.
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Affiliation(s)
- Hailey Choi
- Department of Biology, University of California, Riverside, CA 92521, United States; Graduate program in Cell, Molecular and Developmental Biology, University of California, Riverside, CA 92521, United States
| | - Gina Broitman-Maduro
- Department of Biology, University of California, Riverside, CA 92521, United States
| | - Morris F Maduro
- Department of Biology, University of California, Riverside, CA 92521, United States.
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22
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Tatard VM, Venier-Julienne MC, Benoit JP, Menei P, Montero-Menei CN. In Vivo Evaluation of Pharmacologically Active Microcarriers Releasing Nerve Growth Factor and Conveying PC12 Cells. Cell Transplant 2017; 13:573-83. [PMID: 15565869 DOI: 10.3727/000000004783983675] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Cell therapy will probably become a major therapeutic strategy in the coming years. Nevertheless, few cells survive transplantation when employed as a treatment for neuronal disorders. To address this problem, we have developed a new tool, the pharmacologically active microcarriers (PAM). PAM are biocompatible and biodegradable microparticles coated with cell adhesion molecules, conveying cells on their surface and presenting a controlled delivery of growth factor. Thus, the combined effect of growth factor and coating influences the transported cells by promoting their survival and differentiation and favoring their integration in the host tissue after their complete degradation. Furthermore, the released factor may also influence the microenvironment. In this study, we evaluated their efficacy using nerve growth factor (NGF)-releasing PAM and PC12 cells, in a Parkinson's disease paradigm. After implantation of NGF-releasing or unloaded PAM conveying PC12 cells, or PC12 cells alone, we studied cell survival, differentiation, and apoptosis, as well as behavior of the treated rats. We observed that the NGF-releasing PAM coated with two synthetic peptides (poly-D-lysine and fibronectin-like) induced PC12 cell differentiation and reduced cell death and proliferation. Moreover, the animals receiving this implant presented an improved amphetamine-induced rotational behavior. These findings indicate that PAM could be a promising strategy for cell therapy of neurological diseases and could be employed in other situations with fetal cell transplants or with stem cells.
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Affiliation(s)
- V M Tatard
- INSERM U 646, Laboratoire d'Ingénierie de la vectorisation particulaire, 10 rue André Boquel, 49100 Angers, France
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23
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Lee YJ, Cintora P, Arikkath J, Akinsola O, Kandel M, Popescu G, Best-Popescu C. Quantitative assessment of neural outgrowth using spatial light interference microscopy. J Biomed Opt 2017; 22:66015. [PMID: 28655053 PMCID: PMC5482290 DOI: 10.1117/1.jbo.22.6.066015] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Accepted: 05/30/2017] [Indexed: 05/12/2023]
Abstract
Optimal growth as well as branching of axons and dendrites is critical for the nervous system function. Neuritic length, arborization, and growth rate determine the innervation properties of neurons and define each cell’s computational capability. Thus, to investigate the nervous system function, we need to develop methods and instrumentation techniques capable of quantifying various aspects of neural network formation: neuron process extension, retraction, stability, and branching. During the last three decades, fluorescence microscopy has yielded enormous advances in our understanding of neurobiology. While fluorescent markers provide valuable specificity to imaging, photobleaching, and photoxicity often limit the duration of the investigation. Here, we used spatial light interference microscopy (SLIM) to measure quantitatively neurite outgrowth as a function of cell confluence. Because it is label-free and nondestructive, SLIM allows for long-term investigation over many hours. We found that neurons exhibit a higher growth rate of neurite length in low-confluence versus medium- and high-confluence conditions. We believe this methodology will aid investigators in performing unbiased, nondestructive analysis of morphometric neuronal parameters.
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Affiliation(s)
- Young Jae Lee
- University of Illinois at Urbana-Champaign, Department of Bioengineering, Cellular Neuroscience and Imaging Laboratory, Urbana, Illinois, United States
| | - Pati Cintora
- University of Illinois at Urbana-Champaign, Department of Bioengineering, Cellular Neuroscience and Imaging Laboratory, Urbana, Illinois, United States
| | - Jyothi Arikkath
- University of Nebraska Medical Center, Munroe-Meyer Institute, Omaha, Nebraska, United States
| | - Olaoluwa Akinsola
- University of Illinois at Urbana-Champaign, Beckman Institute for Advanced Science and Technology, Department of Electrical and Computer Engineering, Quantitative Light Imaging Laboratory, Urbana, Illinois, United States
| | - Mikhail Kandel
- University of Illinois at Urbana-Champaign, Beckman Institute for Advanced Science and Technology, Department of Electrical and Computer Engineering, Quantitative Light Imaging Laboratory, Urbana, Illinois, United States
| | - Gabriel Popescu
- University of Illinois at Urbana-Champaign, Beckman Institute for Advanced Science and Technology, Department of Electrical and Computer Engineering, Quantitative Light Imaging Laboratory, Urbana, Illinois, United States
| | - Catherine Best-Popescu
- University of Illinois at Urbana-Champaign, Department of Bioengineering, Cellular Neuroscience and Imaging Laboratory, Urbana, Illinois, United States
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24
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Abdelsalam DG, Yasui T. High brightness, low coherence, digital holographic microscopy for 3D visualization of an in-vitro sandwiched biological sample. Appl Opt 2017; 56:F1-F6. [PMID: 28463291 DOI: 10.1364/ao.56.0000f1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2016] [Accepted: 12/20/2016] [Indexed: 06/07/2023]
Abstract
We achieve practically a bright-field digital holographic microscopy (DHM) configuration free from coherent noise for three-dimensional (3D) visualization of an in-vitro sandwiched sarcomere sample. Visualization of such sandwiched samples by conventional atomic force microscope (AFM) is impossible, while visualization using DHM with long coherent lengths is challenging. The proposed configuration is comprised of an ultrashort pulse laser source and a Mach-Zehnder interferometer in transmission. Periodically poled lithium niobate (PPLN) crystal was used to convert the fundamental beam by second harmonic generation (SHG) to the generated beam fit to the CCD camera used. The experimental results show that the contrast of the reconstructed phase image is improved to a higher degree compared to a He-Ne laser based result. We attribute this improvement to two things: the feature of the femtosecond pulse light, which acts as a chopper for coherent noise suppression, and the fact that the variance of a coherent mode can be reduced by a factor of 9 due to low loss through a nonlinear medium.
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25
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Wang G, Chen H, Wang X, Peng L, Peng Y, Li YQ. Probing the germination kinetics of ethanol-treated Bacillus thuringiensis spores. Appl Opt 2017; 56:3263-3269. [PMID: 28430241 DOI: 10.1364/ao.56.003263] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Bacillus thuringiensis (Bt) is the most widely used microbial insecticide. To clarify the mechanism of bacterial resistance to ethanol toxicity, the present study investigated the effects of 70% (v/v) ethanol at a moderate temperature (65°C) on Bt spore germination by single-cell Raman spectroscopy and differential interference contrast microscopy. We found that over 80% of Bt spores were inviable after 30 min of treatment. Moreover, ethanol treatment affected spore germination; the time for initiation of rapid calcium dipicolinate (CaDPA) release (i.e., lag time, Tlag), time taken for rapid CaDPA release (i.e., ΔTrelease), and time required for complete hydrolysis of the peptidoglycan cortex of spores (i.e., ΔTlys) were increased with longer treatment times. Alanine-initiated germination upon ethanol treatment for 30-90 min showed a 2- to 4-fold longer Tlag, 2- to 3.5-fold longer ΔTrelease, and ∼2-fold longer ΔTlys relative to the control. Dodecylamine-initiated germination treated for 15-30 min had 3- to 5-fold longer Tlag and 1.4- to 1.7-fold longer ΔTrelease than the control. Germination induced by exogenous CaDPA was observed only in a small fraction of spores treated with ethanol for 5 min. Single-cell Raman spectroscopy revealed that more than 52% of spores lost CaDPA after 30 min of ethanol treatment; these showed reductions in the intensity of 1280 and 1652 cm-1 bands (corresponding to protein α-helical structure) and increases in that of 1245 and 1665 cm-1 bands (attributed to irregularities in protein structure). These results indicate that CaDPA in the core of Bt spores confers resistance to ethanol, and that damage to the spore inner membrane by ethanol treatment results in CaDPA leakage. Additionally, moderate-temperature ethanol treatment and consequent denaturation of germination-related proteins affected spore germination, specifically by inactivating the cortex-lytic enzyme CwlJ. Our findings provide a theoretical basis for the development of more effective methods for killing spore-forming bacteria; microscopy imaging and Raman spectroscopy can provide novel insight into the effects of chemical agents on microbial cells.
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Yamane H, Takakura A, Shimadzu Y, Kodama T, Lee JW, Isogai Y, Ishizuya T, Takao-Kawabata R, Iimura T. Acute development of cortical porosity and endosteal naïve bone formation from the daily but not weekly short-term administration of PTH in rabbit. PLoS One 2017; 12:e0175329. [PMID: 28394900 PMCID: PMC5386260 DOI: 10.1371/journal.pone.0175329] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2017] [Accepted: 03/23/2017] [Indexed: 12/18/2022] Open
Abstract
Teriparatide [human parathyroid hormone (1–34)], which exerts an anabolic effect on bone, is used for the treatment of osteoporosis in patients who are at a high risk for fracture. That the once-daily administration of teriparatide causes an increase in cortical porosity in animal models and clinical studies has been a matter of concern. However, it is not well documented that the frequency of administration and/or the total dose of teriparatide affect the cortical porosity. The present study developed 4 teriparatide regimens [20 μg/kg/day (D20), 40 μg/kg/day (D40), 140 μg/kg/week (W140) and 280 μg/kg/week (W280)] in the rabbit as a model animal with a well-developed Haversian system and osteons. The total weekly doses were equivalent in the low-dose groups (D20 and W140) and in the high-dose groups (D40 and W280). After the short-term (1 month) administration of TPDT, micro-CT, histomorphometry and three-dimensional second harmonic generation (3D-SHG) imaging to visualize the bone collagen demonstrated that daily regimens but not weekly regimens were associated with the significant development of cortical porosity and endosteal naïve bone formation by marrow fibrosis. We concomitantly monitored the pharmacokinetics of the plasma teriparatide levels as well as the temporal changes in markers of bone formation and resorption. The analyses in the present study suggested that the daily repeated administration of teriparatide causes more deleterious changes in the cortical microarchitecture than the less frequent administration of higher doses. The findings of the present study may have some implications for use of teriparatide in clinical treatment.
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Affiliation(s)
- Hiroshi Yamane
- Laboratory for Pharmacology, Pharmaceutical Research Center, Asahi Kasei Pharma Corporation, Shizuoka, Japan
| | - Aya Takakura
- Laboratory for Pharmacology, Pharmaceutical Research Center, Asahi Kasei Pharma Corporation, Shizuoka, Japan
- Division of Analytical Bio-Medicine, Graduate School of Medicine, Ehime University, Shitukawa, Toon city, Ehime, Japan
| | - Yukari Shimadzu
- Laboratory for Pharmacology, Pharmaceutical Research Center, Asahi Kasei Pharma Corporation, Shizuoka, Japan
| | - Toshiyuki Kodama
- Laboratory for Safety Assessment and ADME, Pharmaceutical Research Center, Asahi Kasei Pharma Corporation, Shizuoka, Japan
| | - Ji-Won Lee
- Division of Bio-Imaging, Proteo-Science Center (PROS), Ehime University, Shitukawa, Toon city, Ehime, Japan
| | - Yukihiro Isogai
- Laboratory for Pharmacology, Pharmaceutical Research Center, Asahi Kasei Pharma Corporation, Shizuoka, Japan
- Medical Affairs Department, Pharmaceutical Business Administration Division, Asahi Kasei Pharma Corporation, Tokyo, Japan
| | - Toshinori Ishizuya
- Laboratory for Pharmacology, Pharmaceutical Research Center, Asahi Kasei Pharma Corporation, Shizuoka, Japan
| | - Ryoko Takao-Kawabata
- Laboratory for Pharmacology, Pharmaceutical Research Center, Asahi Kasei Pharma Corporation, Shizuoka, Japan
- * E-mail: (RT-K); (TI)
| | - Tadahiro Iimura
- Division of Analytical Bio-Medicine, Graduate School of Medicine, Ehime University, Shitukawa, Toon city, Ehime, Japan
- Division of Bio-Imaging, Proteo-Science Center (PROS), Ehime University, Shitukawa, Toon city, Ehime, Japan
- Division of Analytical Bio-Medicine, Advanced Research Support Center (ADRES), Ehime University, Shitukawa, Toon city, Ehime, Japan
- Artificial Joint Integrated Center, Ehime University Hospital, Shitukawa, Toon city, Ehime, Japan
- * E-mail: (RT-K); (TI)
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Cherkezyan L, Zhang D, Subramanian H, Capoglu I, Taflove A, Backman V. Review of interferometric spectroscopy of scattered light for the quantification of subdiffractional structure of biomaterials. J Biomed Opt 2017; 22:30901. [PMID: 28290596 PMCID: PMC5348632 DOI: 10.1117/1.jbo.22.3.030901] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2016] [Accepted: 02/20/2017] [Indexed: 05/19/2023]
Abstract
Optical microscopy is the staple technique in the examination of microscale material structure in basic science and applied research. Of particular importance to biology and medical research is the visualization and analysis of the weakly scattering biological cells and tissues. However, the resolution of optical microscopy is limited to ? 200 ?? nm due to the fundamental diffraction limit of light. We review one distinct form of the spectroscopic microscopy (SM) method, which is founded in the analysis of the second-order spectral statistic of a wavelength-dependent bright-field far-zone reflected-light microscope image. This technique offers clear advantages for biomedical research by alleviating two notorious challenges of the optical evaluation of biomaterials: the diffraction limit of light and the lack of sensitivity to biological, optically transparent structures. Addressing the first issue, it has been shown that the spectroscopic content of a bright-field microscope image quantifies structural composition of samples at arbitrarily small length scales, limited by the signal-to-noise ratio of the detector, without necessarily resolving them. Addressing the second issue, SM utilizes a reference arm, sample arm interference scheme, which allows us to elevate the weak scattering signal from biomaterials above the instrument noise floor.
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Affiliation(s)
- Lusik Cherkezyan
- Northwestern University, Department of Biomedical Engineering, Evanston, Illinois, United States
| | - Di Zhang
- Northwestern University, Department of Biomedical Engineering, Evanston, Illinois, United States
| | - Hariharan Subramanian
- Northwestern University, Department of Biomedical Engineering, Evanston, Illinois, United States
| | - Ilker Capoglu
- Northwestern University, Department of Biomedical Engineering, Evanston, Illinois, United States
| | - Allen Taflove
- Northwestern University, Department of Electrical Engineering, Evanston, Illinois, United States
| | - Vadim Backman
- Northwestern University, Department of Biomedical Engineering, Evanston, Illinois, United States
- Address all correspondence to: Vadim Backman, E-mail:
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Leung KP, Crowe TD, Abercrombie JJ, Molina CM, Bradshaw CJ, Jensen CL, Luo Q, Thompson GA. Control of Oral Biofilm Formation by an Antimicrobial Decapeptide. J Dent Res 2016; 84:1172-7. [PMID: 16304449 DOI: 10.1177/154405910508401215] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Oral biofilms are mixed-species microbial communities, and their uncontrolled outgrowth can express as oral diseases. Antimicrobial peptides represent alternative classes of antimicrobials that exhibit selectivity for prokaryotes. We wanted to test the effect of a synthetic decapeptide antimicrobial, KSL, on the development of oral biofilms formed by isolated human salivary bacteria. We used differential interference contrast microscopy, coupled with a dual-flow cell system, to determine the effect of KSL on oral biofilm development. We used reductions of viable counts and confocal microscopy to assess the bactericidal activity of KSL on mature oral biofilms. KSL effectively blocked biofilm development. A significant effect on the viability of mature biofilms was observed when KSL was used in the presence of a surface-active agent, or after biofilms were mechanically disrupted. This study shows that KSL may be a useful adjunct for conventional oral hygiene to prevent plaque-mediated dental diseases.
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Affiliation(s)
- K-P Leung
- Microbiology Branch, US Army Dental and Trauma Research Detachment, Walter Reed Army Institute of Research, 310B, B Street, Building 1H, Great Lakes, IL 60088, USA.
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Luchini A, Gerelli Y, Fragneto G, Nylander T, Pálsson GK, Appavou MS, Paduano L. Neutron Reflectometry reveals the interaction between functionalized SPIONs and the surface of lipid bilayers. Colloids Surf B Biointerfaces 2016; 151:76-87. [PMID: 27987458 DOI: 10.1016/j.colsurfb.2016.12.005] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Revised: 12/02/2016] [Accepted: 12/06/2016] [Indexed: 11/18/2022]
Abstract
The safe application of nanotechnology devices in biomedicine requires fundamental understanding on how they interact with and affect the different components of biological systems. In this respect, the cellular membrane, the cell envelope, certainly represents an important target or barrier for nanosystems. Here we report on the interaction between functionalized SuperParamagnetic Iron Oxide Nanoparticles (SPIONs), promising contrast agents for Magnetic Resonance Imaging (MRI), and lipid bilayers that mimic the plasma membrane. Neutron Reflectometry, supported by Quartz Crystal Microbalance with Dissipation monitoring (QCM-D) experiments, was used to characterize this interaction by varying both SPION coating and lipid bilayer composition. In particular, the interaction of two different SPIONs, functionalized with a cationic surfactant and a zwitterionic phospholipid, and lipid bilayers, containing different amount of cholesterol, were compared. The obtained results were further validated by Dynamic Light Scattering (DLS) measurements and Cryogenic Transmission Electron Microscopy (Cryo-TEM) images. None of the investigated functionalized SPIONs were found to disrupt the lipid membrane. However, in all case we observed the attachment of the functionalized SPIONs onto the surface of the bilayers, which was affected by the bilayer rigidity, i.e. the cholesterol concentration.
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Affiliation(s)
- Alessandra Luchini
- Dipartimento di Scienze Chimiche, Università degli Studi di Napoli "Federico II", Complesso Universitario di Monte S. Angelo, via Cintia, 80126 Napoli, Italy; CSGI - Consorzio interuniversitario per lo sviluppo dei Sistemi a Grande Interfase, Italy; Institut Laue-Langevin, BP 156, 71 Avenue des Martyrs, 38000 Grenoble, France
| | - Yuri Gerelli
- Institut Laue-Langevin, BP 156, 71 Avenue des Martyrs, 38000 Grenoble, France
| | - Giovanna Fragneto
- Institut Laue-Langevin, BP 156, 71 Avenue des Martyrs, 38000 Grenoble, France
| | - Tommy Nylander
- Physical Chemistry 1, Lund University, P.O. Box 124, 221 00 Lund, Sweden
| | - Gunnar K Pálsson
- Institut Laue-Langevin, 71 Avenue des Martyrs, 38000 Grenoble, France; Department of Physics and Astronomy, Uppsala University, Box 516, SE-75120 Uppsala, Sweden
| | - Marie-Sousai Appavou
- Jülich Centre for Neutron Science, Garching Forschungszentrum, Lichtenbergstrasse 1, D-85747 Garching bei München, Germany
| | - Luigi Paduano
- Dipartimento di Scienze Chimiche, Università degli Studi di Napoli "Federico II", Complesso Universitario di Monte S. Angelo, via Cintia, 80126 Napoli, Italy; CSGI - Consorzio interuniversitario per lo sviluppo dei Sistemi a Grande Interfase, Italy.
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Sprangers K, Avramova V, Beemster GTS. Kinematic Analysis of Cell Division and Expansion: Quantifying the Cellular Basis of Growth and Sampling Developmental Zones in Zea mays Leaves. J Vis Exp 2016:54887. [PMID: 28060300 PMCID: PMC5226352 DOI: 10.3791/54887] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Growth analyses are often used in plant science to investigate contrasting genotypes and the effect of environmental conditions. The cellular aspect of these analyses is of crucial importance, because growth is driven by cell division and cell elongation. Kinematic analysis represents a methodology to quantify these two processes. Moreover, this technique is easy to use in non-specialized laboratories. Here, we present a protocol for performing a kinematic analysis in monocotyledonous maize (Zea mays) leaves. Two aspects are presented: (1) the quantification of cell division and expansion parameters, and (2) the determination of the location of the developmental zones. This could serve as a basis for sampling design and/or could be useful for data interpretation of biochemical and molecular measurements with high spatial resolution in the leaf growth zone. The growth zone of maize leaves is harvested during steady-state growth. Individual leaves are used for meristem length determination using a DAPI stain and cell-length profiles using DIC microscopy. The protocol is suited for emerged monocotyledonous leaves harvested during steady-state growth, with growth zones spanning at least several centimeters. To improve the understanding of plant growth regulation, data on growth and molecular studies must be combined. Therefore, an important advantage of kinematic analysis is the possibility to correlate changes at the molecular level to well-defined stages of cellular development. Furthermore, it allows for a more focused sampling of specified developmental stages, which is useful in case of limited budget or time.
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Hosaki-Takamiya R, Hashimoto M, Imai Y, Nishida T, Yamada N, Mori H, Tanaka T, Kawanabe N, Yamashiro T, Kamioka H. Collagen production of osteoblasts revealed by ultra-high voltage electron microscopy. J Bone Miner Metab 2016. [PMID: 26224362 DOI: 10.1007/s00774-015-0692-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
In the bone, collagen fibrils form a lamellar structure called the "twisted plywood-like model." Because of this unique structure, bone can withstand various mechanical stresses. However, the formation of this structure has not been elucidated because of the difficulty of observing the collagen fibril production of the osteoblasts via currently available methods. This is because the formation occurs in the very limited space between the osteoblast layer and bone matrix. In this study, we used ultra-high-voltage electron microscopy (UHVEM) to observe collagen fibril production three-dimensionally. UHVEM has 3-MV acceleration voltage and enables us to use thicker sections. We observed collagen fibrils that were beneath the cell membrane of osteoblasts elongated to the outside of the cell. We also observed that osteoblasts produced collagen fibrils with polarity. By using AVIZO software, we observed collagen fibrils produced by osteoblasts along the contour of the osteoblasts toward the bone matrix area. Immediately after being released from the cell, the fibrils run randomly and sparsely. But as they recede from the osteoblast, the fibrils began to run parallel to the definite direction and became thick, and we observed a periodical stripe at that area. Furthermore, we also observed membrane structures wrapped around filamentous structures inside the osteoblasts. The filamentous structures had densities similar to the collagen fibrils and a columnar form and diameter. Our results suggested that collagen fibrils run parallel and thickly, which may be related to the lateral movement of the osteoblasts. UHVEM is a powerful tool for observing collagen fibril production.
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Affiliation(s)
- Rumiko Hosaki-Takamiya
- Department of Orthodontics, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, 2-5-1 Shikata, Kita-ku, Okayama, Okayama, 700-8525, Japan
| | - Mana Hashimoto
- Department of Orthodontics, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, 2-5-1 Shikata, Kita-ku, Okayama, Okayama, 700-8525, Japan
| | - Yuichi Imai
- Department of Orthodontics, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, 2-5-1 Shikata, Kita-ku, Okayama, Okayama, 700-8525, Japan
| | - Tomoki Nishida
- Research Center for Ultra-High Voltage Electron Microscopy, Osaka University, 7-1, Mihogaoka, Ibaraki, Osaka, 567-0047, Japan
| | - Naoko Yamada
- Research Center for Ultra-High Voltage Electron Microscopy, Osaka University, 7-1, Mihogaoka, Ibaraki, Osaka, 567-0047, Japan
| | - Hirotaro Mori
- Research Center for Ultra-High Voltage Electron Microscopy, Osaka University, 7-1, Mihogaoka, Ibaraki, Osaka, 567-0047, Japan
| | - Tomoyo Tanaka
- Department of Orthodontics, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, 2-5-1 Shikata, Kita-ku, Okayama, Okayama, 700-8525, Japan
| | - Noriaki Kawanabe
- Department of Orthodontics, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, 2-5-1 Shikata, Kita-ku, Okayama, Okayama, 700-8525, Japan
| | - Takashi Yamashiro
- Department of Orthodontics and Dentofacial Orthopedics, Graduate School of Dentistry, Osaka University, 1-8 Yamada-Oka, Suita, Osaka, 565-0871, Japan
| | - Hiroshi Kamioka
- Department of Orthodontics, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, 2-5-1 Shikata, Kita-ku, Okayama, Okayama, 700-8525, Japan.
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Franks RG. Histological Analysis of the Arabidopsis Gynoecium and Ovules Using Chloral Hydrate Clearing and Differential Interference Contrast Light Microscopy. Methods Mol Biol 2016; 1457:1-7. [PMID: 27557569 DOI: 10.1007/978-1-4939-3795-0_1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
The use of chloral hydrate optical clearing paired with differential interference contrast microscopy allows the analysis of internal structures of developing plant organs without the need for paraffin embedding and sectioning. This approach is appropriate for the analysis of the developing gynoecium or seedpod of the flowering plant Arabidopsis thaliana and many other types of fixed plant material. Early stages of ovule development are observable with this approach.
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Affiliation(s)
- Robert G Franks
- Department of Plant and Microbial Biology, North Carolina State University, 2548 Thomas Hall, Raleigh, NC, 27695-7614, USA.
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Ou G, Thakar D, Tung JC, Miroshnikova YA, Dufort CC, Gutierrez E, Groisman A, Weaver VM. Visualizing mechanical modulation of nanoscale organization of cell-matrix adhesions. Integr Biol (Camb) 2016; 8:795-804. [PMID: 27334548 PMCID: PMC4980125 DOI: 10.1039/c6ib00031b] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
The mechanical properties of the extracellular matrix influence cell signaling to regulate key cellular processes, including differentiation, apoptosis, and transformation. Understanding the molecular mechanisms underlying mechanotransduction is contingent upon our ability to visualize the effect of altered matrix properties on the nanoscale organization of proteins involved in this signalling. The development of super-resolution imaging techniques has afforded researchers unprecedented ability to probe the organization and localization of proteins within the cell. However, most of these methods require use of substrates like glass or silicon wafers, which are artificially rigid. In light of a growing body of literature demonstrating the importance of mechanical properties of the extracellular matrix in regulating many aspects of cellular behavior and signaling, we have developed a system that allows scanning angle interference microscopy on a mechanically tunable substrate. We describe its implementation in detail and provide examples of how it may be used to aide investigations into the effect of substrate rigidity on intracellular signaling.
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Affiliation(s)
- Guanqing Ou
- University of California, Berkeley and University of California, San Francisco Joint Graduate Group in Bioengineering, San Francisco, CA, USA
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Larimer C, Suter JD, Bonheyo G, Addleman RS. In situ non-destructive measurement of biofilm thickness and topology in an interferometric optical microscope. J Biophotonics 2016; 9:656-666. [PMID: 26992071 DOI: 10.1002/jbio.201500212] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [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: 08/10/2015] [Revised: 01/27/2016] [Accepted: 02/21/2016] [Indexed: 06/05/2023]
Abstract
Biofilms are ubiquitous and impact the environment, human health, dental hygiene, and a wide range of industrial processes. Biofilms are difficult to characterize when fully hydrated, especially in a non-destructive manner, because of their soft structure and water-like bulk properties. Herein a method of measuring and monitoring the thickness and topology of live biofilms of using white light interferometry is described. Using this technique, surface morphology, surface roughness, and biofilm thickness were measured over time without while the biofilm continued to grow. The thickness and surface topology of a P. putida biofilm were monitored growing from initial colonization to a mature biofilm. Measured thickness followed expected trends for bacterial growth. Surface roughness also increased over time and was a leading indicator of biofilm growth.
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Affiliation(s)
- Curtis Larimer
- Pacific Northwest National Laboratory, Battelle for the USDOE, PO Box 999, MSIN P7-50, Richland, WA, 99354, USA
| | - Jonathan D Suter
- Pacific Northwest National Laboratory, Battelle for the USDOE, PO Box 999, MSIN P7-50, Richland, WA, 99354, USA
| | - George Bonheyo
- Pacific Northwest National Laboratory, Battelle for the USDOE, PO Box 999, MSIN P7-50, Richland, WA, 99354, USA
| | - Raymond Shane Addleman
- Pacific Northwest National Laboratory, Battelle for the USDOE, PO Box 999, MSIN P7-50, Richland, WA, 99354, USA.
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Monzel C, Schmidt D, Seifert U, Smith AS, Merkel R, Sengupta K. Nanometric thermal fluctuations of weakly confined biomembranes measured with microsecond time-resolution. Soft Matter 2016; 12:4755-4768. [PMID: 27142463 DOI: 10.1039/c6sm00412a] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We probe the bending fluctuations of bio-membranes using highly deflated giant unilamellar vesicles (GUVs) bound to a substrate by a weak potential arising from generic interactions. The substrate is either homogeneous, with GUVs bound only by the weak potential, or is chemically functionalized with a micro-pattern of very strong specific binders. In both cases, the weakly adhered membrane is seen to be confined at a well-defined distance above the surface while it continues to fluctuate strongly. We quantify the fluctuations of the weakly confined membrane at the substrate proximal surface as well as of the free membrane at the distal surface of the same GUV. This strategy enables us to probe in detail the damping of fluctuations in the presence of the substrate, and to independently measure the membrane tension and the strength of the generic interaction potential. Measurements were done using two complementary techniques - dynamic optical displacement spectroscopy (DODS, resolution: 20 nm, 10 μs), and dual wavelength reflection interference contrast microscopy (DW-RICM, resolution: 4 nm, 50 ms). After accounting for the spatio-temporal resolution of the techniques, an excellent agreement between the two measurements was obtained. For both weakly confined systems we explore in detail the link between fluctuations on the one hand and membrane tension and the interaction potential on the other hand.
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Affiliation(s)
- Cornelia Monzel
- Aix-Marseille Université, CNRS UMR 7325 (Centre Interdisciplinaire de Nanosciences de Marseille - CINaM), Marseille Cedex 9, France. and Institute of Complex Systems 7 (ICS-7), Forschungszentrum Jülich, Jülich, Germany
| | - Daniel Schmidt
- II. Institut für Theoretische Physik, Universität Stuttgart, Germany and Institut für Theoretische Physik, Friedrich Alexander Universität Erlangen-Nürnberg, Germany
| | - Udo Seifert
- II. Institut für Theoretische Physik, Universität Stuttgart, Germany
| | - Ana-Sunčana Smith
- Institut für Theoretische Physik, Friedrich Alexander Universität Erlangen-Nürnberg, Germany and Division of Physical Chemistry, Ruđer Bošković Institute, 10000 Zagreb, Croatia
| | - Rudolf Merkel
- Institute of Complex Systems 7 (ICS-7), Forschungszentrum Jülich, Jülich, Germany
| | - Kheya Sengupta
- Aix-Marseille Université, CNRS UMR 7325 (Centre Interdisciplinaire de Nanosciences de Marseille - CINaM), Marseille Cedex 9, France.
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Huerre A, Jullien MC, Theodoly O, Valignat MP. Absolute 3D reconstruction of thin films topography in microfluidic channels by interference reflection microscopy. Lab Chip 2016; 16:911-916. [PMID: 26830018 DOI: 10.1039/c5lc01417d] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The travel of droplets, bubbles, vesicles, capsules, living cells or small organisms in microchannels is a hallmark in microfluidics applications. A full description of the dynamics of such objects requires a quantitative understanding of the complex hydrodynamic and interfacial interactions between objects and channel walls. In this paper, we present an interferometric method that allows absolute topographic reconstruction of the interspace between an object and channel walls for objects confined in microfluidic channels. Wide field microscopic imaging in reflection interference contrast mode (RICM) is directly performed at the bottom wall of microfluidic chips. Importantly, we show that the reflections at both the lower and upper surface of the microchannel have to be considered in the quantitative analysis of the optical signal. More precisely, the contribution of the reflection at the upper surface is weighted depending on the light coherence length and channel height. Using several wavelengths and illumination apertures, our method allows reconstructing the topography of thin films on channel walls in a range of 0-500 nm, with a precision as accurate as 2 nm for the thinnest films. A complete description of the protocol is exemplified for oil in water droplets travelling in channels of height 10-400 μm at a speed up to 5 mm s(-1).
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Affiliation(s)
- A Huerre
- MMN, UMR CNRS Gulliver 7083, PSL research University, ESPCI ParisTech, 10 rue Vauquelin, F-75005 Paris, France
| | - M-C Jullien
- MMN, UMR CNRS Gulliver 7083, PSL research University, ESPCI ParisTech, 10 rue Vauquelin, F-75005 Paris, France
| | - O Theodoly
- LAI, INSERM UMR S 1067, CNRS UMR 7333, Aix-Marseille Universite 13009 Marseille, France
| | - M-P Valignat
- LAI, INSERM UMR S 1067, CNRS UMR 7333, Aix-Marseille Universite 13009 Marseille, France
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Berthaud A, Quemeneur F, Deforet M, Bassereau P, Brochard-Wyart F, Mangenot S. Spreading of porous vesicles subjected to osmotic shocks: the role of aquaporins. Soft Matter 2016; 12:1601-1609. [PMID: 26662491 DOI: 10.1039/c5sm01654a] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Aquaporin 0 (AQP0) is a transmembrane protein specific to the eye lens, involved as a water carrier across the lipid membranes. During eye lens maturation, AQP0s are truncated by proteolytic cleavage. We investigate in this work the capability of truncated AQP0 to conduct water across membranes. We developed a method to accurately determine water permeability across lipid membranes and across proteins from the deflation under osmotic pressure of giant unilamellar vesicles (GUVs) deposited on an adhesive substrate. Using reflection interference contrast microscopy (RICM), we measure the spreading area of GUVs during deswelling. We interpret these results using a model based on hydrodynamic, binder diffusion towards the contact zone, and Helfrich's law for the membrane tension, which allows us to relate the spread area to the vesicle internal volume. We first study the specific adhesion of vesicles coated with biotin spreading on a streptavidin substrate. We then determine the permeability of a single functional AQP0 and demonstrate that truncated AQP0 is no more a water channel.
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Affiliation(s)
- Alice Berthaud
- Laboratoire Physico Chimie Curie, Institut Curie, PSL Research University, CNRS UMR168, 75005, Paris, France.
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Kuchel PW, Shishmarev D, Puckeridge M, Levitt MH, Naumann C, Chapman BE. NMR of (133)Cs(+) in stretched hydrogels: One-dimensional, z- and NOESY spectra, and probing the ion's environment in erythrocytes. J Magn Reson 2015; 261:110-120. [PMID: 26561738 DOI: 10.1016/j.jmr.2015.10.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [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: 06/23/2015] [Revised: 10/18/2015] [Accepted: 10/21/2015] [Indexed: 06/05/2023]
Abstract
(133)Cs nuclear magnetic resonance (NMR) spectroscopy was conducted on (133)Cs(+) in gelatin hydrogels that were either relaxed or stretched. Stretching generated a septet from this spin-7/2 nucleus, and its nuclear magnetic relaxation was studied via z-spectra, and two-dimensional nuclear Overhauser (NOESY) spectroscopy. Various spectral features were well simulated by using Mathematica and the software package SpinDynamica. Spectra of CsCl in suspensions of human erythrocytes embedded in gelatin gel showed separation of the resonances from the cation inside and outside the cells. Upon stretching the sample, the extracellular (133)Cs(+) signal split into a septet, while the intracellular peak was unchanged, revealing different alignment/ordering properties of the environment inside and around the cells. Differential interference contrast light microscopy confirmed that the cells were stretched when the overall sample was elongated. Analysis of the various spectral features of (133)Cs(+) reported here opens up applications of this K(+) congener for studies of cation-handling by metabolically-active cells and tissues in aligned states.
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Affiliation(s)
- Philip W Kuchel
- School of Molecular Bioscience, University of Sydney, NSW 2006, Australia.
| | - Dmitry Shishmarev
- School of Molecular Bioscience, University of Sydney, NSW 2006, Australia
| | - Max Puckeridge
- School of Molecular Bioscience, University of Sydney, NSW 2006, Australia
| | - Malcolm H Levitt
- Department of Chemistry, University of Southampton, Highfield, SO17 1BJ, UK
| | - Christoph Naumann
- School of Molecular Bioscience, University of Sydney, NSW 2006, Australia
| | - Bogdan E Chapman
- School of Molecular Bioscience, University of Sydney, NSW 2006, Australia
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Nozaki H, Matsuzaki R, Yamamoto K, Kawachi M, Takahashi F. Delineating a New Heterothallic Species of Volvox (Volvocaceae, Chlorophyceae) Using New Strains of "Volvox africanus". PLoS One 2015; 10:e0142632. [PMID: 26562165 PMCID: PMC4643018 DOI: 10.1371/journal.pone.0142632] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Accepted: 10/23/2015] [Indexed: 11/18/2022] Open
Abstract
The volvocine algae represent an excellent model lineage in which to study evolution of female and male genders based on comparative analyses of related species. Among these species, Volvox carteri has been extensively studied as a model of an oogamous and complex organism. However, it may have unique derived features that are not present in other species of Volvox. Therefore, information regarding the characteristics of sexual reproduction of other species of Volvox is also important. In 1971, Starr studied four types of sexuality in several global strains identified as Volvox africanus; however, further taxonomic studies of these strains have been lacking, and strains of three of the four sexual types are not available. Here, we studied the morphology, sexual reproduction, and taxonomy of two V. africanus-like species isolated recently from Lake Biwa, Japan. These two species were very similar to two sexual types described by Starr in 1971: one producing dioecious sexual spheroids in heterothallic strains and the other forming both male spheroids and monoecious spheroids in a single strain. The former species produced zygotes with a reticulate cell wall, whereas a smooth zygote wall was observed in the latter species as in V. africanus previously reported from various localities around the world. Our multigene phylogenetic analysis demonstrated that these are sister species to each other. However, the presence of a compensatory base change in the most conserved region of the secondary structure of nuclear ribosomal DNA internal transcribed spacer-2, hybrid inviability demonstrated by intercrossing experiments, and morphological differences in the density of abutment between the gelatinous material of adjacent cells (individual sheaths) in the spheroid supported the recognition of the two species, V. africanus having a smooth zygote wall and V. reticuliferus Nozaki sp. nov. having a reticulate zygote wall.
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Affiliation(s)
- Hisayoshi Nozaki
- Department of Biological Sciences, Graduate school of Science, University of Tokyo, Tokyo, Japan
- * E-mail:
| | - Ryo Matsuzaki
- Department of Biological Sciences, Graduate school of Science, University of Tokyo, Tokyo, Japan
| | - Kayoko Yamamoto
- Department of Biological Sciences, Graduate school of Science, University of Tokyo, Tokyo, Japan
| | - Masanobu Kawachi
- Center for Environmental Biology and Ecosystem Studies, National Institute for Environmental Studies, Tsukuba, Ibaraki, Japan
| | - Fumio Takahashi
- Ritsumeikan University, College of Life Sciences, Kusatsu, Shiga, Japan
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40
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Buchner O, Moser T, Karadar M, Roach T, Kranner I, Holzinger A. Formation of chloroplast protrusions and catalase activity in alpine Ranunculus glacialis under elevated temperature and different CO2/O2 ratios. Protoplasma 2015; 252:1613-9. [PMID: 25701381 PMCID: PMC4628086 DOI: 10.1007/s00709-015-0778-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Accepted: 02/09/2015] [Indexed: 05/23/2023]
Abstract
Chloroplast protrusions (CPs) have frequently been observed in plants, but their significance to plant metabolism remains largely unknown. We investigated in the alpine plant Ranunculus glacialis L. treated under various CO2 concentrations if CP formation is related to photorespiration, specifically focusing on hydrogen peroxide (H2O2) metabolism. Immediately after exposure to different CO2 concentrations, the formation of CPs in leaf mesophyll cells was assessed and correlated to catalase (CAT) and ascorbate peroxidase (APX) activities. Under natural irradiation, the relative proportion of chloroplasts with protrusions (rCP) was highest (58.7 %) after exposure to low CO2 (38 ppm) and was lowest (3.0 %) at high CO2 (10,000 ppm). The same relationship was found for CAT activity, which decreased from 34.7 nkat mg(-1) DW under low CO2 to 18.4 nkat mg(-1) DW under high CO2, while APX activity did not change significantly. When exposed to natural CO2 concentration (380 ppm) in darkness, CP formation was significantly lower (18.2 %) compared to natural solar irradiation (41.3 %). In summary, CP formation and CAT activity are significantly increased under conditions that favour photorespiration, while in darkness or at high CO2 concentration under light, CP formation is significantly lower, providing evidence for an association between CPs and photorespiration.
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Affiliation(s)
- Othmar Buchner
- Institute of Botany, Functional Plant Biology, University of Innsbruck, Sternwartestrasse 15, 6020, Innsbruck, Austria.
| | - Tim Moser
- Institute of Botany, Functional Plant Biology, University of Innsbruck, Sternwartestrasse 15, 6020, Innsbruck, Austria
| | - Matthias Karadar
- Institute of Botany, Functional Plant Biology, University of Innsbruck, Sternwartestrasse 15, 6020, Innsbruck, Austria
| | - Thomas Roach
- Institute of Botany, Functional Plant Biology, University of Innsbruck, Sternwartestrasse 15, 6020, Innsbruck, Austria
| | - Ilse Kranner
- Institute of Botany, Functional Plant Biology, University of Innsbruck, Sternwartestrasse 15, 6020, Innsbruck, Austria
| | - Andreas Holzinger
- Institute of Botany, Functional Plant Biology, University of Innsbruck, Sternwartestrasse 15, 6020, Innsbruck, Austria
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Monzel C, Veschgini M, Madsen J, Lewis AL, Armes SP, Tanaka M. Fine Adjustment of Interfacial Potential between pH-Responsive Hydrogels and Cell-Sized Particles. Langmuir 2015; 31:8689-8696. [PMID: 26190346 DOI: 10.1021/acs.langmuir.5b01896] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We quantitatively determined interfacial potentials between cell-sized particles and stimulus-responsive hydrogels using a microinterferometer. The hydrogel is based on physically interconnected ABA triblock copolymer micelles comprising an inner biocompatible PMPC block and two outer pH-responsive PDPA blocks. The out-of-plane temporal fluctuation in the position of the cell-sized particles was calculated from changes in the interference pattern measured by Reflection Interference Contrast Microscopy (RICM), thus yielding the particle-substrate interaction potential V (Δh). Measurements in pH buffers ranging from 7.0 to 7.8 resulted in a systematic reduction in height of the potential minima ⟨Δh⟩ and a concomitant increase in the potential curvature V″ (Δh). The experimental data were analyzed by applying the modified Ross and Pincus model for polyelectrolytes, while accounting for gravitation, lubrication and van der Waals interactions. Elastic moduli calculated from V″ (Δh) were in good agreement with those measured by Atomic Force Microscopy. The ability to fine-tune both the gel elasticity and the interfacial potential at around physiological pH makes such triblock copolymer hydrogels a promising biocompatible substrate for dynamic switching of cell-material interactions.
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Affiliation(s)
- Cornelia Monzel
- †Physical Chemistry of Biosystems, Institute of Physical Chemistry, University of Heidelberg, 69120 Heidelberg, Germany
| | - Mariam Veschgini
- †Physical Chemistry of Biosystems, Institute of Physical Chemistry, University of Heidelberg, 69120 Heidelberg, Germany
| | - Jeppe Madsen
- ‡Department of Chemistry, Dainton Building, University of Sheffield, Brook Hill, Sheffield, South Yorkshire, S3 7HF, United Kingdom
| | - Andrew L Lewis
- §Biocompatibles UK, Ltd., Chapman House, Farnham Business Park, Weydon Lane, Farnham, Surrey GU9 8 QL, United Kingdom
| | - Steven P Armes
- ‡Department of Chemistry, Dainton Building, University of Sheffield, Brook Hill, Sheffield, South Yorkshire, S3 7HF, United Kingdom
| | - Motomu Tanaka
- †Physical Chemistry of Biosystems, Institute of Physical Chemistry, University of Heidelberg, 69120 Heidelberg, Germany
- ∥Institute for Integrated Cell-Material Sciences (WPI iCeMS), Kyoto University, 606-8501, Kyoto, Japan
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Landi S, Gargani E, Paoli F, Simoni S, Roversi PF. Morphological Markers for Cryopreservation in the Embryonic Development of Drosophila suzukii (Diptera: Drosophilidae). J Econ Entomol 2015; 108:1875-1883. [PMID: 26470330 DOI: 10.1093/jee/tov114] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [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: 07/28/2014] [Accepted: 04/15/2015] [Indexed: 06/05/2023]
Abstract
Drosophila suzukii (Matsumura) (Diptera: Drosophilidae) is an invasive pest recently reported in Europe whose spread into new areas has caused severe economic damage to many agricultural crops. There are serious concerns about the currently available chemical insecticides because of their low efficacy in controlling the species and their environmental impact; so, several studies have focused on environmentally safe strategies. The sterile insect technique (SIT), which requires colony maintenance in laboratory and production of large numbers of live animals, can be utilized in pest management programs and could be integrated with other control strategies if the potential risks associated with the rearing and maintenance of the insect line under laboratory conditions are given sufficient attention. In this regard, the ability to cryobiologically preserve such stocks would be of substantial value. Important prerequisites for long-term cryopreservation are determination of the embryonic stages, identification of specific embryonic stages, and knowledge of development time. This paper describes the main visible markers for the different stages of embryonic development and determines the timing of development at 25°C. D. suzukii embryogenesis lasts 23-25 h at 25°C and can be divided into 17 stages defined by specific morphological markers. The point at which 50% of embryos are at Stage 14 and 50% are at Stage 15, the most tolerant stages for cryopreservation treatment, as ascertained for Drosophila melanogaster Meigen in prior studies, is reached in 14-15 h. The efficiency of this procedure might be impaired by the retention of eggs in the oviducts, making it impossible to determine the stage of embryonic development for ∼25% of laid eggs.
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Affiliation(s)
- Silvia Landi
- Consiglio per la ricerca in agricoltura e l'analisi dell'economia agraria, Centro di Ricerca per l'Agrobiologia e la Pedologia (CRA-ABP), via di Lanciola 12/a, Cascine del Riccio, 50125 Firenze, Italy
| | - Elisabetta Gargani
- Consiglio per la ricerca in agricoltura e l'analisi dell'economia agraria, Centro di Ricerca per l'Agrobiologia e la Pedologia (CRA-ABP), via di Lanciola 12/a, Cascine del Riccio, 50125 Firenze, Italy
| | - Francesco Paoli
- Consiglio per la ricerca in agricoltura e l'analisi dell'economia agraria, Centro di Ricerca per l'Agrobiologia e la Pedologia (CRA-ABP), via di Lanciola 12/a, Cascine del Riccio, 50125 Firenze, Italy
| | - Sauro Simoni
- Consiglio per la ricerca in agricoltura e l'analisi dell'economia agraria, Centro di Ricerca per l'Agrobiologia e la Pedologia (CRA-ABP), via di Lanciola 12/a, Cascine del Riccio, 50125 Firenze, Italy
| | - Pio Federico Roversi
- Consiglio per la ricerca in agricoltura e l'analisi dell'economia agraria, Centro di Ricerca per l'Agrobiologia e la Pedologia (CRA-ABP), via di Lanciola 12/a, Cascine del Riccio, 50125 Firenze, Italy
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Todaro MA, Dal Zotto M, Leasi F. An Integrated Morphological and Molecular Approach to the Description and Systematisation of a Novel Genus and Species of Macrodasyida (Gastrotricha). PLoS One 2015; 10:e0130278. [PMID: 26153694 PMCID: PMC4496097 DOI: 10.1371/journal.pone.0130278] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2015] [Accepted: 05/17/2015] [Indexed: 12/05/2022] Open
Abstract
BACKGROUND Gastrotricha systematics is in a state of flux mainly due to the conflicts between cladistic studies base on molecular markers and the classical systematisation based on morphological traits. In sandy samples from Thailand, we found numerous macrodasyidan gastrotrichs belonging to an undescribed species of difficult taxonomic affiliation. The abundance and original nature of the specimens prompted us to undertake a deep survey of both morphological and molecular traits aiming at a reliable systematisation of the new taxon. METHODOLOGY/PRINCIPAL FINDINGS Using several microscopical techniques we investigated the external and internal anatomy, including the muscular and nervous systems of the new species. Additional specimens were used to obtain the 18S rRNA gene sequence; molecular data was analysed cladistically in conjunction with data from additional species belonging to the near complete Macrodasyida taxonomic spectrum. Specimens are vermiform, up to 806 μm in total length, and show a well-defined head equipped with peculiar leaf-like sensorial organs and a single-lobed posterior end. The adhesive apparatus includes anterior, ventrolateral, dorsal and posterior tubes. Pharynx is about 1/4 of the total length and shows pores at its posterior 3/4. Adult specimens exhibit maturing eggs and a bulky, muscular caudal organ, but do not show sperm nor the frontal organ. Musculature and nervous system organisation resemble the usual macrodasyidan plan; however, the somatic circular muscles of the intestinal region surround all other muscular components and a third FMRFamide-IR commissure ventral to the pharyngo-intestinal junction appear to be an autoapomorphic traits of the new species. CONCLUSIONS/SIGNIFICANCE While the anatomical characteristics of the Asian specimens appear so unique to grant the establishment of a new taxon, for which the name Thaidasys tongiorgii gen. et sp. nov. is proposed, the result of phylogenetic analyses based on the 18S rRNA gene unites the new genus with the family Macrodasyidae.
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Affiliation(s)
- M. Antonio Todaro
- Department of Life Sciences, University of Modena and Reggio Emilia, Modena, Italy
| | - Matteo Dal Zotto
- Department of Life Sciences, University of Modena and Reggio Emilia, Modena, Italy
- Consorzio Interuniversitario per il Centro di Biologia Marina ed Ecologia Applicata ‘G. Bacci’, Livorno, Italy
| | - Francesca Leasi
- National Museum of Natural History, Smithsonian Institution, Washington, D.C., United States of America
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Rodríguez-Sanz H, Solís MT, López MF, Gómez-Cadenas A, Risueño MC, Testillano PS. Auxin Biosynthesis, Accumulation, Action and Transport are Involved in Stress-Induced Microspore Embryogenesis Initiation and Progression in Brassica napus. Plant Cell Physiol 2015; 56:1401-17. [PMID: 25907568 DOI: 10.1093/pcp/pcv058] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [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: 08/28/2014] [Accepted: 04/07/2015] [Indexed: 05/17/2023]
Abstract
Isolated microspores are reprogrammed in vitro by stress, becoming totipotent cells and producing embryos and plants via a process known as microspore embryogenesis. Despite the abundance of data on auxin involvement in plant development and embryogenesis, no data are available regarding the dynamics of auxin concentration, cellular localization and the expression of biosynthesis genes during microspore embryogenesis. This work involved the analysis of auxin concentration and cellular accumulation; expression of TAA1 and NIT2 encoding enzymes of two auxin biosynthetic pathways; expression of the PIN1-like efflux carrier; and the effects of inhibition of auxin transport and action by N-1-naphthylphthalamic acid (NPA) and α-(p-chlorophenoxy) isobutyric acid (PCIB) during Brassica napus microspore embryogenesis. The results indicated de novo auxin synthesis after stress-induced microspore reprogramming and embryogenesis initiation, accompanying the first cell divisions. The progressive increase of auxin concentration during progression of embryogenesis correlated with the expression patterns of TAA1 and NIT2 genes of auxin biosynthetic pathways. Auxin was evenly distributed in early embryos, whereas in heart/torpedo embryos auxin was accumulated in apical and basal embryo regions. Auxin efflux carrier PIN1-like gene expression was induced in early multicellular embryos and increased at the globular/torpedo embryo stages. Inhibition of polar auxin transport (PAT) and action, by NPA and PCIB, impaired embryo development, indicating that PAT and auxin action are required for microspore embryo progression. NPA also modified auxin embryo accumulation patterns. These findings indicate that endogenous auxin biosynthesis, action and polar transport are required in stress-induced microspore reprogramming, embryogenesis initiation and progression.
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Affiliation(s)
- Héctor Rodríguez-Sanz
- Pollen Biotechnology of Crop Plants group, Centro de Investigaciones Biológicas (CIB) CSIC, Ramiro de Maeztu 9, 28040 Madrid, Spain
| | - María-Teresa Solís
- Pollen Biotechnology of Crop Plants group, Centro de Investigaciones Biológicas (CIB) CSIC, Ramiro de Maeztu 9, 28040 Madrid, Spain
| | - María-Fernanda López
- Departamento de Ciencias Agrarias y del Medio Natural, Universidad Jaume I, Campus Riu Sec, 12071, Castellón, Spain
| | - Aurelio Gómez-Cadenas
- Departamento de Ciencias Agrarias y del Medio Natural, Universidad Jaume I, Campus Riu Sec, 12071, Castellón, Spain
| | - María C Risueño
- Pollen Biotechnology of Crop Plants group, Centro de Investigaciones Biológicas (CIB) CSIC, Ramiro de Maeztu 9, 28040 Madrid, Spain
| | - Pilar S Testillano
- Pollen Biotechnology of Crop Plants group, Centro de Investigaciones Biológicas (CIB) CSIC, Ramiro de Maeztu 9, 28040 Madrid, Spain
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Fina JP, Casati P. HAG3, a Histone Acetyltransferase, Affects UV-B Responses by Negatively Regulating the Expression of DNA Repair Enzymes and Sunscreen Content in Arabidopsis thaliana. Plant Cell Physiol 2015; 56:1388-400. [PMID: 25907565 DOI: 10.1093/pcp/pcv054] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [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: 01/09/2015] [Accepted: 04/02/2015] [Indexed: 05/23/2023]
Abstract
Histone acetylation is regulated by histone acetyltransferases and deacetylases. In Arabidopsis, there are 12 histone acetyltransferases and 18 deacetylases. Histone acetyltransferases are organized in four families: the GNAT/HAG, the MYST, the p300/CBP and the TAFII250 families. Previously, we demonstrated that Arabidopsis mutants in the two members of the MYST acetyltransferase family show increased DNA damage after UV-B irradiation. To investigate further the role of other histone acetyltransferases in UV-B responses, a putative role for enzymes of the GNAT family, HAG1, HAG2 and HAG3, was analyzed. HAG transcripts are not UV-B regulated; however, hag3 RNA interference (RNAi) transgenic plants show a lower inhibition of leaf and root growth by UV-B, higher levels of UV-B-absorbing compounds and less UV-B-induced DNA damage than Wassilewskija (Ws) plants, while hag1 RNAi transgenic plants and hag2 mutants do not show significant differences from wild-type plants. Transcripts for UV-B-regulated genes are highly expressed under control conditions in the absence of UV-B in hag3 RNAi transgenic plants, suggesting that the higher UV-B tolerance may be due to increased levels of proteins that participate in UV-B responses. Together, our data provide evidence that HAG3, directly or indirectly, participates in UV-B-induced DNA damage repair and signaling.
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Affiliation(s)
- Julieta P Fina
- Centro de Estudios Fotosintéticos y Bioquímicos (CEFOBI), Universidad Nacional de Rosario, Suipacha 531, 2000 Rosario, Argentina
| | - Paula Casati
- Centro de Estudios Fotosintéticos y Bioquímicos (CEFOBI), Universidad Nacional de Rosario, Suipacha 531, 2000 Rosario, Argentina
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Atkin-Smith GK, Tixeira R, Paone S, Mathivanan S, Collins C, Liem M, Goodall KJ, Ravichandran KS, Hulett MD, Poon IK. A novel mechanism of generating extracellular vesicles during apoptosis via a beads-on-a-string membrane structure. Nat Commun 2015; 6:7439. [PMID: 26074490 PMCID: PMC4490561 DOI: 10.1038/ncomms8439] [Citation(s) in RCA: 240] [Impact Index Per Article: 26.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2015] [Accepted: 05/07/2015] [Indexed: 12/15/2022] Open
Abstract
Disassembly of apoptotic cells into smaller fragments (a form of extracellular vesicle called apoptotic bodies) can facilitate removal of apoptotic debris and intercellular communication. However, the mechanism underpinning this process is unclear. While observing monocytes undergoing apoptosis by time-lapse microscopy, we discovered a new type of membrane protrusion that resembles a 'beads-on-a-string' structure. Strikingly, the 'beads' are frequently sheared off the 'string' to form apoptotic bodies. Generation of apoptotic bodies via this mechanism can facilitate a sorting process and results in the exclusion of nuclear contents from apoptotic bodies. Mechanistically, generation of 'beads-on-a-string' protrusion is controlled by the level of actomyosin contraction and apoptopodia formation. Furthermore, in an unbiased drug screen, we identified the ability of sertraline (an antidepressant) to block the formation of 'beads-on-a-string' protrusions and apoptotic bodies. These data uncover a new mechanism of apoptotic body formation in monocytes and also compounds that can modulate this process.
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Affiliation(s)
- Georgia K. Atkin-Smith
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria 3086, Australia
| | - Rochelle Tixeira
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria 3086, Australia
| | - Stephanie Paone
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria 3086, Australia
| | - Suresh Mathivanan
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria 3086, Australia
| | - Christine Collins
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria 3086, Australia
| | - Michael Liem
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria 3086, Australia
| | - Katharine J. Goodall
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria 3086, Australia
| | - Kodi S. Ravichandran
- Department of Microbiology, Center for Cell Clearance, University of Virginia, Charlottesville, Virginia 22908, USA
| | - Mark D. Hulett
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria 3086, Australia
| | - Ivan K.H. Poon
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria 3086, Australia
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Leopold LE, Heestand BN, Seong S, Shtessel L, Ahmed S. Lack of pairing during meiosis triggers multigenerational transgene silencing in Caenorhabditis elegans. Proc Natl Acad Sci U S A 2015; 112:E2667-76. [PMID: 25941370 PMCID: PMC4443339 DOI: 10.1073/pnas.1501979112] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Single-copy transgenes in Caenorhabditis elegans can be subjected to a potent, irreversible silencing process termed small RNA-induced epigenetic silencing (RNAe). RNAe is promoted by the Piwi Argonaute protein PRG-1 and associated Piwi-interacting RNAs (piRNAs), as well as by proteins that promote and respond to secondary small interfering RNA (siRNA) production. Here we define a related siRNA-mediated silencing process, termed "multigenerational RNAe," which can occur for transgenes that are maintained in a hemizygous state for several generations. We found that transgenes that contain either GFP or mCherry epitope tags can be silenced via multigenerational RNAe, whereas a transgene that possesses GFP and a perfect piRNA target site can be rapidly and permanently silenced via RNAe. Although previous studies have shown that PRG-1 is typically dispensable for maintenance of RNAe, we found that both initiation and maintenance of multigenerational RNAe requires PRG-1 and the secondary siRNA biogenesis protein RDE-2. Although silencing via RNAe is irreversible, we found that transgene expression can be restored when hemizygous transgenes that were silenced via multigenerational RNAe become homozygous. Furthermore, multigenerational RNAe was accelerated when meiotic pairing of the chromosome possessing the transgene was abolished. We propose that persistent lack of pairing during meiosis elicits a reversible multigenerational silencing response, which can lead to permanent transgene silencing. Multigenerational RNAe may be broadly relevant to single-copy transgenes used in experimental biology and to shaping the epigenomic landscape of diverse species, where genomic polymorphisms between homologous chromosomes commonly result in unpaired DNA during meiosis.
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Affiliation(s)
| | - Bree N Heestand
- Department of Genetics, Lineberger Comprehensive Cancer Center, and
| | | | | | - Shawn Ahmed
- Department of Genetics, Lineberger Comprehensive Cancer Center, and Department of Biology, University of North Carolina, Chapel Hill, NC 27599-3280
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Bender M, Thon JN, Ehrlicher AJ, Wu S, Mazutis L, Deschmann E, Sola-Visner M, Italiano JE, Hartwig JH. Microtubule sliding drives proplatelet elongation and is dependent on cytoplasmic dynein. Blood 2015; 125:860-8. [PMID: 25411426 PMCID: PMC4311231 DOI: 10.1182/blood-2014-09-600858] [Citation(s) in RCA: 74] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Accepted: 11/08/2014] [Indexed: 01/04/2023] Open
Abstract
Bone marrow megakaryocytes produce platelets by extending long cytoplasmic protrusions, designated proplatelets, into sinusoidal blood vessels. Although microtubules are known to regulate platelet production, the underlying mechanism of proplatelet elongation has yet to be resolved. Here we report that proplatelet formation is a process that can be divided into repetitive phases (extension, pause, and retraction), as revealed by differential interference contrast and fluorescence loss after photoconversion time-lapse microscopy. Furthermore, we show that microtubule sliding drives proplatelet elongation and is dependent on cytoplasmic dynein under static and physiological shear stress by using fluorescence recovery after photobleaching in proplatelets with fluorescence-tagged β1-tubulin. A refined understanding of the specific mechanisms regulating platelet production will yield strategies to treat patients with thrombocythemia or thrombocytopenia.
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Affiliation(s)
| | - Jonathan N Thon
- Hematology Division, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA; Platelet BioGenesis, Chestnut Hill, MA
| | - Allen J Ehrlicher
- School of Engineering and Applied Sciences, Harvard University, Cambridge, MA; Department of Bioengineering, McGill University, Montreal, QC, Canada
| | - Stephen Wu
- Hematology Division, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA
| | - Linas Mazutis
- Platelet BioGenesis, Chestnut Hill, MA; School of Engineering and Applied Sciences, Harvard University, Cambridge, MA; Institute of Biotechnology, Vilnius University, Vilnius, Lithuania
| | - Emoke Deschmann
- Division of Newborn Medicine, Boston Children's Hospital and Harvard Medical School, Boston, MA; Division of Neonatology, Department of Women's and Children's Health, Karolinska Institutet, Stockholm, Sweden
| | - Martha Sola-Visner
- Division of Newborn Medicine, Boston Children's Hospital and Harvard Medical School, Boston, MA
| | - Joseph E Italiano
- Hematology Division, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA; Platelet BioGenesis, Chestnut Hill, MA; Department of Surgery, Vascular Biology Program, Boston Children's Hospital, Boston, MA; and
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Lo KL, Wang LC, Chen IJ, Liu YC, Chung MC, Lo WS. Transcriptional consequence and impaired gametogenesis with high-grade aneuploidy in Arabidopsis thaliana. PLoS One 2014; 9:e114617. [PMID: 25514186 PMCID: PMC4267805 DOI: 10.1371/journal.pone.0114617] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2014] [Accepted: 11/12/2014] [Indexed: 12/11/2022] Open
Abstract
Aneuploidy features a numerical chromosome variant that the number of chromosomes in the nucleus of a cell is not an exact multiple of the haploid number, which may have an impact on morphology and gene expression. Here we report a tertiary trisomy uncovered by characterizing a T-DNA insertion mutant (aur2-1/+) in the Arabidopsis (Arabidopsis thaliana) AURORA2 locus. Whole-genome analysis with DNA tiling arrays revealed a chromosomal translocation linked to the aur2-1 allele, which collectively accounted for a tertiary trisomy 2. Morphologic, cytogenetic and genetic analyses of aur2-1 progeny showed impaired male and female gametogenesis to various degrees and a tight association of the aur2-1 allele with the tertiary trisomy that was preferentially inherited. Transcriptome analysis showed overlapping and distinct gene expression profiles between primary and tertiary trisomy 2 plants, particularly genes involved in response to stress and various types of external and internal stimuli. Additionally, transcriptome and gene ontology analyses revealed an overrepresentation of nuclear-encoded organelle-related genes functionally involved in plastids, mitochondria and peroxisomes that were differentially expressed in at least three if not all Arabidopsis trisomics. These observations support a previous hypothesis that aneuploid cells have higher energy requirement to overcome the detrimental effects of an unbalanced genome. Moreover, our findings extend the knowledge of the complex nature of the T-DNA insertion event influencing plant genomic integrity by creating high-grade trisomy. Finally, gene expression profiling results provide useful information for future research to compare primary and tertiary trisomics for the effects of aneuploidy on plant cell physiology.
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Affiliation(s)
- Kuan-Lin Lo
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, Taiwan
| | - Long-Chi Wang
- Biotechnology Center, National Chung-Hsing University, Taichung, Taiwan
| | - I-Ju Chen
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, Taiwan
| | - Yu-Chen Liu
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, Taiwan
| | - Mei-Chu Chung
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, Taiwan
| | - Wan-Sheng Lo
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, Taiwan
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