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Modzel M, Solanko KA, Szomek M, Hansen SK, Dupont A, Nåbo LJ, Kongsted J, Wüstner D. Live-cell imaging of new polyene sterols for improved analysis of intracellular cholesterol transport. J Microsc 2018. [PMID: 29516493 DOI: 10.1111/jmi.12691] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Analysis of intracellular cholesterol transport by fluorescence microscopy requires suitable fluorescent analogues of cholesterol. Most existing cholesterol analogues contain lipophilic dyes which can compromise the sterol properties in membranes. An alternative strategy is to introduce additional double bonds into the sterol ring system resulting in intrinsic fluorescence, while at the same time keeping the cholesterol-like properties of the analogues. Existing polyene sterols, such as dehydroergosterol (DHE) or cholestatrienol (CTL), however, contain only three double bonds and suffer from low brightness, significant photobleaching and excitation/emission in the ultraviolet region. Thus, special equipment is required to image such sterols. Here, we describe synthesis, characterization and intracellular imaging of new polyene sterols containing four conjugated double bonds in the sterol ring system. We show that such analogues have red-shifted excitation and emission by ∼20 nm compared to DHE or CTL. The red shift was even more pronounced when preventing keto-enol tautomer equilibration by protecting the 3'-hydroxy group with acetate. We show that the latter analogue can be imaged on a conventional wide field microscope with a DAPI/filipin filter cube. The new polyene sterols show reduced photobleaching compared to DHE or CTL allowing for improved deconvolution microscopy of sterol containing cellular membranes.
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Affiliation(s)
- M Modzel
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, DK-5230 Odense, Denmark
| | - K A Solanko
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, DK-5230 Odense, Denmark
| | - M Szomek
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, DK-5230 Odense, Denmark
| | - S K Hansen
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, DK-5230 Odense, Denmark
| | - A Dupont
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, DK-5230 Odense, Denmark
| | - L J Nåbo
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, DK-5230 Odense, Denmark
| | - J Kongsted
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, DK-5230 Odense, Denmark
| | - D Wüstner
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, DK-5230 Odense, Denmark
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Nåbo LJ, List NH, Steinmann C, Kongsted J. Computational Approach to Evaluation of Optical Properties of Membrane Probes. J Chem Theory Comput 2017; 13:719-726. [DOI: 10.1021/acs.jctc.6b01017] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Lina J. Nåbo
- Department
of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, 5230 Odense M, Denmark
| | - Nanna Holmgaard List
- Division
of Theoretical Chemistry and Biology, School of Biotechnology, KTH Royal Institute of Technology, SE-106 91 Stockholm, Sweden
| | - Casper Steinmann
- Centre
for Computational Chemistry, School of Chemistry, University of Bristol, Bristol BS8 1TS, United Kingdom
| | - Jacob Kongsted
- Department
of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, 5230 Odense M, Denmark
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3
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Kraft ML. Sphingolipid Organization in the Plasma Membrane and the Mechanisms That Influence It. Front Cell Dev Biol 2017; 4:154. [PMID: 28119913 PMCID: PMC5222807 DOI: 10.3389/fcell.2016.00154] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2016] [Accepted: 12/27/2016] [Indexed: 11/13/2022] Open
Abstract
Sphingolipids are structural components in the plasma membranes of eukaryotic cells. Their metabolism produces bioactive signaling molecules that modulate fundamental cellular processes. The segregation of sphingolipids into distinct membrane domains is likely essential for cellular function. This review presents the early studies of sphingolipid distribution in the plasma membranes of mammalian cells that shaped the most popular current model of plasma membrane organization. The results of traditional imaging studies of sphingolipid distribution in stimulated and resting cells are described. These data are compared with recent results obtained with advanced imaging techniques, including super-resolution fluorescence detection and high-resolution secondary ion mass spectrometry (SIMS). Emphasis is placed on the new insight into the sphingolipid organization within the plasma membrane that has resulted from the direct imaging of stable isotope-labeled lipids in actual cell membranes with high-resolution SIMS. Super-resolution fluorescence techniques have recently revealed the biophysical behaviors of sphingolipids and the unhindered diffusion of cholesterol analogs in the membranes of living cells are ultimately in contrast to the prevailing hypothetical model of plasma membrane organization. High-resolution SIMS studies also conflicted with the prevailing hypothesis, showing sphingolipids are concentrated in micrometer-scale membrane domains, but cholesterol is evenly distributed within the plasma membrane. Reductions in cellular cholesterol decreased the number of sphingolipid domains in the plasma membrane, whereas disruption of the cytoskeleton eliminated them. In addition, hemagglutinin, a transmembrane protein that is thought to be a putative raft marker, did not cluster within sphingolipid-enriched regions in the plasma membrane. Thus, sphingolipid distribution in the plasma membrane is dependent on the cytoskeleton, but not on favorable interactions with cholesterol or hemagglutinin. The alternate views of plasma membrane organization suggested by these findings are discussed.
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Affiliation(s)
- Mary L Kraft
- Department of Chemical and Biomolecular Engineering, University of Illinois Urbana, IL, USA
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Modzel M, Lund FW, Wüstner D. Synthesis and Live-Cell Imaging of Fluorescent Sterols for Analysis of Intracellular Cholesterol Transport. Methods Mol Biol 2017; 1583:111-140. [PMID: 28205171 DOI: 10.1007/978-1-4939-6875-6_10] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
Abstract
Cellular cholesterol homeostasis relies on precise control of the sterol content of organelle membranes. Obtaining insight into cholesterol trafficking pathways and kinetics by live-cell imaging relies on two conditions. First, one needs to develop suitable analogs that resemble cholesterol as closely as possible with respect to their biophysical and biochemical properties. Second, the cholesterol analogs should have good fluorescence properties. This interferes, however, often with the first requirement, such that the imaging instrumentation must be optimized to collect photons from suboptimal fluorophores, but good cholesterol mimics, such as the intrinsically fluorescent sterols, cholestatrienol (CTL) or dehydroergosterol (DHE). CTL differs from cholesterol only in having two additional double bonds in the ring system, which is why it is slightly fluorescent in the ultraviolet (UV). In the first part of this protocol, we describe how to synthesize and image CTL in living cells relative to caveolin, a structural component of caveolae. In the second part, we explain in detail how to perform time-lapse experiments of commercially available BODIPY-tagged cholesterol (TopFluor-cholesterol®; TF-Chol) in comparison to DHE. Finally, using two-photon time-lapse imaging data of TF-Chol, we demonstrate how to use our imaging toolbox SpatTrack for tracking sterol rich vesicles in living cells over time.
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Affiliation(s)
- Maciej Modzel
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Campusvej 55, Odense M, 5230, Denmark
| | - Frederik W Lund
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Campusvej 55, Odense M, 5230, Denmark.,Department of Biochemistry, Weill Medical College of Cornell University, New York, NY, 10065, USA
| | - Daniel Wüstner
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Campusvej 55, Odense M, 5230, Denmark.
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Solanko KA, Modzel M, Solanko LM, Wüstner D. Fluorescent Sterols and Cholesteryl Esters as Probes for Intracellular Cholesterol Transport. Lipid Insights 2016; 8:95-114. [PMID: 27330304 PMCID: PMC4902042 DOI: 10.4137/lpi.s31617] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2015] [Revised: 04/04/2016] [Accepted: 04/07/2016] [Indexed: 12/20/2022] Open
Abstract
Cholesterol transport between cellular organelles comprised vesicular trafficking and nonvesicular exchange; these processes are often studied by quantitative fluorescence microscopy. A major challenge for using this approach is producing analogs of cholesterol with suitable brightness and structural and chemical properties comparable with those of cholesterol. This review surveys currently used fluorescent sterols with respect to their behavior in model membranes, their photophysical properties, as well as their transport and metabolism in cells. In the first part, several intrinsically fluorescent sterols, such as dehydroergosterol or cholestatrienol, are discussed. These polyene sterols (P-sterols) contain three conjugated double bonds in the steroid ring system, giving them slight fluorescence in ultraviolet light. We discuss the properties of P-sterols relative to cholesterol, outline their chemical synthesis, and explain how to image them in living cells and organisms. In particular, we show that P-sterol esters inserted into low-density lipoprotein can be tracked in the fibroblasts of Niemann–Pick disease using high-resolution deconvolution microscopy. We also describe fluorophore-tagged cholesterol probes, such as BODIPY-, NBD-, Dansyl-, or Pyrene-tagged cholesterol, and eventual esters of these analogs. Finally, we survey the latest developments in the synthesis and use of alkyne cholesterol analogs to be labeled with fluorophores by click chemistry and discuss the potential of all approaches for future applications.
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Affiliation(s)
- Katarzyna A Solanko
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense M, Denmark
| | - Maciej Modzel
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense M, Denmark
| | - Lukasz M Solanko
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense M, Denmark
| | - Daniel Wüstner
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense M, Denmark
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Imaging approaches for analysis of cholesterol distribution and dynamics in the plasma membrane. Chem Phys Lipids 2016; 199:106-135. [PMID: 27016337 DOI: 10.1016/j.chemphyslip.2016.03.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Accepted: 03/04/2016] [Indexed: 11/21/2022]
Abstract
Cholesterol is an important lipid component of the plasma membrane (PM) of mammalian cells, where it is involved in control of many physiological processes, such as endocytosis, cell migration, cell signalling and surface ruffling. In an attempt to explain these functions of cholesterol, several models have been put forward about cholesterol's lateral and transbilayer organization in the PM. In this article, we review imaging techniques developed over the last two decades for assessing the distribution and dynamics of cholesterol in the PM of mammalian cells. Particular focus is on fluorescence techniques to study the lateral and inter-leaflet distribution of suitable cholesterol analogues in the PM of living cells. We describe also several methods for determining lateral cholesterol dynamics in the PM including fluorescence recovery after photobleaching (FRAP), fluorescence correlation spectroscopy (FCS), single particle tracking (SPT) and spot variation FCS coupled to stimulated emission depletion (STED) microscopy. For proper interpretation of such measurements, we provide some background in probe photophysics and diffusion phenomena occurring in cell membranes. In particular, we show the equivalence of the reaction-diffusion approach, as used in FRAP and FCS, and continuous time random walk (CTRW) models, as often invoked in SPT studies. We also discuss mass spectrometry (MS) based imaging of cholesterol in the PM of fixed cells and compare this method with fluorescence imaging of sterols. We conclude that evidence from many experimental techniques converges towards a model of a homogeneous distribution of cholesterol with largely free and unhindered diffusion in both leaflets of the PM.
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Wüstner D, Lund FW, Röhrl C, Stangl H. Potential of BODIPY-cholesterol for analysis of cholesterol transport and diffusion in living cells. Chem Phys Lipids 2016; 194:12-28. [DOI: 10.1016/j.chemphyslip.2015.08.007] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2015] [Revised: 08/07/2015] [Accepted: 08/12/2015] [Indexed: 01/04/2023]
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8
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Nåbo LJ, List NH, Witzke S, Wüstner D, Khandelia H, Kongsted J. Design of new fluorescent cholesterol and ergosterol analogs: Insights from theory. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2015; 1848:2188-99. [DOI: 10.1016/j.bbamem.2015.04.018] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Revised: 04/24/2015] [Accepted: 04/29/2015] [Indexed: 12/23/2022]
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Wüstner D, Solanko K. How cholesterol interacts with proteins and lipids during its intracellular transport. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2015; 1848:1908-26. [DOI: 10.1016/j.bbamem.2015.05.010] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2015] [Revised: 04/14/2015] [Accepted: 05/13/2015] [Indexed: 12/13/2022]
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10
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Solanko LM, Honigmann A, Midtiby HS, Lund FW, Brewer JR, Dekaris V, Bittman R, Eggeling C, Wüstner D. Membrane orientation and lateral diffusion of BODIPY-cholesterol as a function of probe structure. Biophys J 2014; 105:2082-92. [PMID: 24209853 DOI: 10.1016/j.bpj.2013.09.031] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2013] [Revised: 08/26/2013] [Accepted: 09/16/2013] [Indexed: 11/29/2022] Open
Abstract
Cholesterol tagged with the BODIPY fluorophore via the central difluoroboron moiety of the dye (B-Chol) is a promising probe for studying intracellular cholesterol dynamics. We synthesized a new BODIPY-cholesterol probe (B-P-Chol) with the fluorophore attached via one of its pyrrole rings to carbon-24 of cholesterol (B-P-Chol). Using two-photon fluorescence polarimetry in giant unilamellar vesicles and in the plasma membrane (PM) of living intact and actin-disrupted cells, we show that the BODIPY-groups in B-Chol and B-P-Chol are oriented perpendicular and almost parallel to the bilayer normal, respectively. B-Chol is in all three membrane systems much stronger oriented than B-P-Chol. Interestingly, we found that the lateral diffusion in the PM was two times slower for B-Chol than for B-P-Chol, although we found no difference in lateral diffusion in model membranes. Stimulated emission depletion microscopy, performed for the first time, to our knowledge, with fluorescent sterols, revealed that the difference in lateral diffusion of the BODIPY-cholesterol probes was not caused by anomalous subdiffusion, because diffusion of both analogs in the PM was free but not hindered. Our combined measurements show that the position and orientation of the BODIPY moiety in cholesterol analogs have a severe influence on lateral diffusion specifically in the PM of living cells.
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Affiliation(s)
- Lukasz M Solanko
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense M, Denmark
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11
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Stanislas T, Grebe M, Boutté Y. Sterol dynamics during endocytic trafficking in Arabidopsis. Methods Mol Biol 2014; 1209:13-29. [PMID: 25117272 DOI: 10.1007/978-1-4939-1420-3_2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Sterols are lipids found in membranes of eukaryotic cells. Functions of sterols have been demonstrated for various cellular processes including endocytic trafficking in animal, fungal, and plant cells. The ability to visualize sterols at the subcellular level is crucial to understand sterol distribution and function during endocytic trafficking. In plant cells, the polyene antibiotic filipin is the most extensively used tool for the specific detection of fluorescently labeled 3-β-hydroxysterols in situ. Filipin can to some extent be used to track sterol internalization in live cells, but this application is limited, due to the inhibitory effects filipin exerts on sterol-dependent endocytosis. Nevertheless, filipin-sterol labeling can be performed on aldehyde-fixed cells which allows for sterol detection in endocytic compartments. This approach can combine studies correlating sterol distribution with experimental manipulations of endocytic trafficking pathways. Here, we describe step-by-step protocols and troubleshooting for procedures on live and fixed cells to visualize sterols during endocytic trafficking. We also provide a detailed discussion of advantages and limitations of both methods. Moreover, we illustrate the use of the endocytic recycling inhibitor brefeldin A and a genetically modified version of one of its target molecules for studying endocytic sterol trafficking.
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Affiliation(s)
- Thomas Stanislas
- Department of Plant Physiology, Umeå Plant Science Centre (UPSC), Umeå University, Umeå, 90 187, Sweden
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12
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Lund FW, Lomholt MA, Solanko LM, Bittman R, Wüstner D. Two-photon time-lapse microscopy of BODIPY-cholesterol reveals anomalous sterol diffusion in chinese hamster ovary cells. BMC BIOPHYSICS 2012; 5:20. [PMID: 23078907 PMCID: PMC3532368 DOI: 10.1186/2046-1682-5-20] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/22/2012] [Accepted: 09/19/2012] [Indexed: 01/08/2023]
Abstract
Background Cholesterol is an important membrane component, but our knowledge about its transport in cells is sparse. Previous imaging studies using dehydroergosterol (DHE), an intrinsically fluorescent sterol from yeast, have established that vesicular and non-vesicular transport modes contribute to sterol trafficking from the plasma membrane. Significant photobleaching, however, limits the possibilities for in-depth analysis of sterol dynamics using DHE. Co-trafficking studies with DHE and the recently introduced fluorescent cholesterol analog BODIPY-cholesterol (BChol) suggested that the latter probe has utility for prolonged live-cell imaging of sterol transport. Results We found that BChol is very photostable under two-photon (2P)-excitation allowing the acquisition of several hundred frames without significant photobleaching. Therefore, long-term tracking and diffusion measurements are possible. Two-photon temporal image correlation spectroscopy (2P-TICS) provided evidence for spatially heterogeneous diffusion constants of BChol varying over two orders of magnitude from the cell interior towards the plasma membrane, where D ~ 1.3 μm2/s. Number and brightness (N&B) analysis together with stochastic simulations suggest that transient partitioning of BChol into convoluted membranes slows local sterol diffusion. We observed sterol endocytosis as well as fusion and fission of sterol-containing endocytic vesicles. The mobility of endocytic vesicles, as studied by particle tracking, is well described by a model for anomalous subdiffusion on short time scales with an anomalous exponent α ~ 0.63 and an anomalous diffusion constant of Dα = 1.95 x 10-3 μm2/sα. On a longer time scale (t > ~5 s), a transition to superdiffusion consistent with slow directed transport with an average velocity of v ~ 6 x 10-3 μm/s was observed. We present an analytical model that bridges the two regimes and fit this model to vesicle trajectories from control cells and cells with disrupted microtubule or actin filaments. Both treatments reduced the anomalous diffusion constant and the velocity by ~40-50%. Conclusions The mobility of sterol-containing vesicles on the short time scale could reflect dynamic rearrangements of the cytoskeleton, while directed transport of sterol vesicles occurs likely along both, microtubules and actin filaments. Spatially varying anomalous diffusion could contribute to fine-tuning and local regulation of intracellular sterol transport.
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Affiliation(s)
- Frederik W Lund
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Campusvej 55, Odense M, DK-5230, Denmark.
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Abstract
Cholesterol plays an important role in determining the biophysical properties of biological membranes, and its concentration is tightly controlled by homeostatic processes. The intracellular transport of cholesterol among organelles is a key part of the homeostatic mechanism, but sterol transport processes are not well understood. Fluorescence microscopy is a valuable tool for studying intracellular transport processes, but this method can be challenging for lipid molecules because addition of a fluorophore may alter the properties of the molecule greatly. We discuss the use of fluorescent molecules that can bind to cholesterol to reveal its distribution in cells. We also discuss the use of intrinsically fluorescent sterols that closely mimic cholesterol, as well as some minimally modified fluorophore-labeled sterols. Methods for imaging these sterols by conventional fluorescence microscopy and by multiphoton microscopy are described. Some label-free methods for imaging cholesterol itself are also discussed briefly.
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Wüstner D, Brewer JR, Bagatolli L, Sage D. Potential of ultraviolet wide-field imaging and multiphoton microscopy for analysis of dehydroergosterol in cellular membranes. Microsc Res Tech 2011; 74:92-108. [PMID: 21181715 DOI: 10.1002/jemt.20878] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Dehydroergosterol (DHE) is an intrinsically fluorescent sterol with absorption/emission in the ultraviolet (UV) region and biophysical properties similar to those of cholesterol. We compared the potential of UV-sensitive low-light-level wide-field (UV-WF) imaging with that of multiphoton (MP) excitation microscopy to monitor DHE in living cells. Significantly reduced photobleaching in MP microscopy of DHE enabled us to acquire three-dimensional z-stacks of DHE-stained cells and to obtain high-resolution maps of DHE in surface ruffles, nanotubes, and the apical membrane of epithelial cells. We found that the lateral resolution of MP microscopy is ∼1.5-fold higher than that of UV-WF deconvolution microscopy, allowing for improved spatiotemporal analysis of plasma membrane sterol distribution. Surface intensity patterns of DHE with a diameter of 0.2 μm persisting over several minutes could be resolved by MP time-lapse microscopy. Diffusion coefficients of 0.25-μm-diameter endocytic vesicles containing DHE were determined by MP spatiotemporal image correlation spectroscopy. The requirement of extremely high laser power for visualization of DHE by MP microscopy made this method less potent for multicolor applications with organelle markers like green fluorescent protein-tagged proteins. The signal-to-noise ratio obtainable by UV-WF imaging could be significantly improved by pixelwise bleach rate fitting and calculation of an amplitude image from the decay model and by frame averaging after pixelwise bleaching correction of the image stacks. We conclude that UV-WF imaging and MP microscopy of DHE provide complementary information regarding membrane distribution and intracellular targeting of sterols.
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Affiliation(s)
- Daniel Wüstner
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, DK-5230 Odense M, Denmark.
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15
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Quantitative assessment of sterol traffic in living cells by dual labeling with dehydroergosterol and BODIPY-cholesterol. Chem Phys Lipids 2011; 164:221-35. [DOI: 10.1016/j.chemphyslip.2011.01.004] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2010] [Revised: 01/14/2011] [Accepted: 01/24/2011] [Indexed: 11/18/2022]
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16
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Extending the knowledge in histochemistry and cell biology. Histochem Cell Biol 2009; 133:1-40. [PMID: 19946696 DOI: 10.1007/s00418-009-0665-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/17/2009] [Indexed: 01/21/2023]
Abstract
Central to modern Histochemistry and Cell Biology stands the need for visualization of cellular and molecular processes. In the past several years, a variety of techniques has been achieved bridging traditional light microscopy, fluorescence microscopy and electron microscopy with powerful software-based post-processing and computer modeling. Researchers now have various tools available to investigate problems of interest from bird's- up to worm's-eye of view, focusing on tissues, cells, proteins or finally single molecules. Applications of new approaches in combination with well-established traditional techniques of mRNA, DNA or protein analysis have led to enlightening and prudent studies which have paved the way toward a better understanding of not only physiological but also pathological processes in the field of cell biology. This review is intended to summarize articles standing for the progress made in "histo-biochemical" techniques and their manifold applications.
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State-of-the-art technologies, current opinions and developments, and novel findings: news from the field of histochemistry and cell biology. Histochem Cell Biol 2008; 130:1205-51. [PMID: 18985372 DOI: 10.1007/s00418-008-0535-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/21/2008] [Indexed: 10/25/2022]
Abstract
Investigations of cell and tissue structure and function using innovative methods and approaches have again yielded numerous exciting findings in recent months and have added important data to current knowledge, inspiring new ideas and hypotheses in various fields of modern life sciences. Topics and contents of comprehensive expert reviews covering different aspects in methodological advances, cell biology, tissue function and morphology, and novel findings reported in original papers are summarized in the present review.
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