Super resolution of time-lapse seismic images

Reliable estimates of vertical, inline, and crossline components of apparent displacements in time-lapse seismic images are difficult to obtain for two reasons. First, features in 3D seismic images tend to be locally planar, and components of displacement within the planes of such features are poorly resolved. Second, searching directly for peaks in 3D crosscorrelations is less robust, more complicated, and computationally more costly than searching for peaks of 1D crosscorrelations. I estimate all three components of displacement with a process designed to mitigate these two problems. I address the first problem by computing for each image sample a local phase correlation instead of a local crosscorrelation. I address the second problem with a cyclic sequence of searches for peaks of correlations computed for lags constrained to one of the three image axes.

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Photoregulated Fluxional Fluorophores for Live-Cell Super-Resolution Microscopy with No Apparent Photobleaching

10.26434/chemrxiv.7165745.v2 ◽

2019 ◽

Author(s):

Elias A. Halabi ◽

Dorothea Pinotsi ◽

Pablo Rivera-Fuentes

Keyword(s):

Single Molecule ◽

Three Dimensional ◽

Super Resolution ◽

Time Lapse ◽

Switching Behavior ◽

Spatiotemporal Resolution ◽

New Information ◽

Human Neurons ◽

Long Time ◽

Intracellular Organelles

Photoswitchable molecules have found multiple applications in the physical and life sciences because their properties can be modulated with light. Fluxional molecules, which undergo rapid degenerate rearrangements in the electronic ground state, also exhibit switching behavior. The stochastic nature of fluxional switching, however, has hampered its application in the development of functional molecules and materials. Here we combine photoswitching and fluxionality to develop a fluorophore that enables very long (>30 min) time-lapse single-molecule localization microscopy in living cells with minimal phototoxicity and no apparent photobleaching. These long time-lapse experiments allowed us to track intracellular organelles with unprecedented spatiotemporal resolution, revealing new information of the three-dimensional compartmentalization of synaptic vesicle trafficking in live human neurons.

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Time-Lapse Super-Resolution Imaging of Apical Membrane Protein Domains in Live Filamentous Fungi

Biophysical Journal ◽

10.1016/j.bpj.2012.11.3599 ◽

2013 ◽

Vol 104 (2) ◽

pp. 652a ◽

Cited By ~ 3

Author(s):

Yuji Ishitsuka ◽

Yiming Li ◽

Reinhard Fischer ◽

Norio Takeshita ◽

G. Ulrich Nienhaus

Keyword(s):

Membrane Protein ◽

Filamentous Fungi ◽

Apical Membrane ◽

Protein Domains ◽

Super Resolution ◽

Time Lapse ◽

Resolution Imaging

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A photoswitchable fluorescent protein for hours-time-lapse and sub-second-resolved super-resolution imaging

Microscopy ◽

10.1093/jmicro/dfab001 ◽

2021 ◽

Author(s):

Tetsuichi Wazawa ◽

Ryohei Noma ◽

Shusaku Uto ◽

Kazunori Sugiura ◽

Takashi Washio ◽

...

Keyword(s):

Mammalian Cells ◽

Fluorescent Protein ◽

Fluorescent Proteins ◽

Ph Dependence ◽

Super Resolution ◽

Time Lapse ◽

Light Irradiation ◽

Acquisition Time ◽

Polarization Angle ◽

Cellular Dynamics

Abstract Reversibly photoswitchable fluorescent proteins (RSFPs) are a class of fluorescent proteins whose fluorescence can be turned on and off by light irradiation. RSFPs have become essential tools for super-resolution (SR) imaging. Because most SR imaging techniques require high-power-density illumination, mitigating phototoxicity in cells due to intense light irradiation has been a challenge. Although we previously developed an RSFP named Kohinoor to achieve SR imaging with low phototoxicity, the photoproperties were insufficient to move a step further to explore the cellular dynamics by SR imaging. Here, we show an improved version of RSFP, Kohinoor2.0, which is suitable for SR imaging of cellular processes. Kohinoor2.0 shows a 2.6-fold higher fluorescence intensity, 2.5-fold faster chromophore maturation and 1.5-fold faster off-switching than Kohinoor. The analysis of the pH dependence of the visible absorption band revealed that Kohinoor2.0 and Kohinoor were in equilibria among multiple fluorescently bright and dark states, with the mutations introduced into Kohinoor2.0 bringing about a higher stabilization of the fluorescently bright states compared to Kohinoor. Using Kohinoor2.0 with our SR imaging technique, super-resolution polarization demodulation/on-state polarization angle narrowing, we conducted 4-h time-lapse SR imaging of an actin filament network in mammalian cells with a total acquisition time of 480 s without a noticeable indication of phototoxicity. Furthermore, we demonstrated the SR imaging of mitochondria dynamics at a time resolution of 0.5 s, in which the fusion and fission processes were clearly visualized. Thus, Kohinoor2.0 is shown to be an invaluable RSFP for the SR imaging of cellular dynamics.

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In vivo super-resolution RESOLFT microscopy of Drosophila melanogaster

eLife ◽

10.7554/elife.15567 ◽

2016 ◽

Vol 5 ◽

Cited By ~ 22

Author(s):

Sebastian Schnorrenberg ◽

Tim Grotjohann ◽

Gerd Vorbrüggen ◽

Alf Herzig ◽

Stefan W Hell ◽

...

Keyword(s):

Drosophila Melanogaster ◽

Fluorescent Protein ◽

Single Cells ◽

Super Resolution ◽

Time Lapse ◽

Live Cell ◽

Model Organisms ◽

Alpha Tubulin ◽

Light Levels

Despite remarkable developments in diffraction unlimited super-resolution microscopy, in vivo nanoscopy of tissues and model organisms is still not satisfactorily established and rarely realized. RESOLFT nanoscopy is particularly suited for live cell imaging because it requires relatively low light levels to overcome the diffraction barrier. Previously, we introduced the reversibly switchable fluorescent protein rsEGFP2, which facilitated fast RESOLFT nanoscopy (<xref ref-type="bibr" rid="bib10">Grotjohann et al., 2012</xref>). In that study, as in most other nanoscopy studies, only cultivated single cells were analyzed. Here, we report on the use of rsEGFP2 for live-cell RESOLFT nanoscopy of sub-cellular structures of intact Drosophila melanogaster larvae and of resected tissues. We generated flies expressing fusion proteins of alpha-tubulin and rsEGFP2 highlighting the microtubule cytoskeleton in all cells. By focusing through the intact larval cuticle, we achieved lateral resolution of <60 nm. RESOLFT nanoscopy enabled time-lapse recordings comprising 40 images and facilitated recordings 40 µm deep within fly tissues.

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‘Live and Large’: Super-Resolution Optical Fluctuation Imaging (SOFI) and Expansion Microscopy (ExM) of Microtubule Remodelling by Rabies Virus P Protein

Australian Journal of Chemistry ◽

10.1071/ch19571 ◽

2020 ◽

Vol 73 (8) ◽

pp. 686

Author(s):

Ashley M. Rozario ◽

Fabian Zwettler ◽

Sam Duwé ◽

Riley B. Hargreaves ◽

Aaron Brice ◽

...

Keyword(s):

Rabies Virus ◽

Super Resolution ◽

Time Lapse ◽

Live Cells ◽

Conventional Imaging ◽

P Protein ◽

Conventional Microscopy ◽

P Proteins ◽

Super Resolution Microscopy

The field of super-resolution microscopy continues to progress rapidly, both in terms of evolving techniques and methodologies as well as in the development of new multi-disciplinary applications. Two current drivers of innovation are increasing the possible resolution gain and application in live samples. Super-resolution optical fluctuation imaging (SOFI) is well suited to live samples while expansion microscopy (ExM) enables obtainment of sub-diffraction information via conventional imaging. In this Highlight we provide a brief outline of these methods and report results from application of SOFI and ExM in our on-going study into microtubule remodelling by rabies virus P proteins. We show that MT bundles in live cells transfected with rabies virus P3 protein can be visualised using SOFI in a time-lapse fashion for up to half an hour and can be expanded using current Pro-ExM protocols and imaged using conventional microscopy.

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