Biology subjects

Yeo, W.-H.

Publications and source records attributed to Yeo, W.-H..

5 recordsLinked to original sources

bioRxiv2024

Implementation and calibration of spectroscopic single-molecule localization microscopy

Spectroscopic single-molecule localization microscopy (sSMLM) allows multi-color super-resolution images with high spectral sensitivity. In this protocol, we provide essential information for researchers to implement sSMLM in a laboratory setting. We describe how to assemble and align the illumination and detection paths of a 3D dual-wedge prism (DWP)-based sSMLM instrument. We provide detailed step-by-step instructions for performing spectral and axial calibration using fluorescent beads and a nanohole array, respectively. We also discuss using sSMLM to image fluorescently labeled cells and report a new MATLAB package, RainbowSTORM v2, to reconstruct super-resolution 3D images. Further, we present representative images as typical anticipated results for users to validate.

bioengineering↗

bioRxiv2024

Transport and Organization of Individual Vimentin Filaments Within Dense Networks Revealed by Single Particle Tracking and 3D FIB-SEM

Vimentin intermediate filaments (VIFs) form complex, tight-packed networks; due to this density, traditional ensemble labeling and imaging approaches cannot accurately discern single filament behavior. To address this, we introduce a sparse vimentin-SunTag labeling strategy to unambiguously visualize individual filament dynamics. This technique confirmed known long-range dynein and kinesin transport of peripheral VIFs and uncovered extensive bidirectional VIF motion within the perinuclear vimentin network, a region we had thought too densely bundled to permit such motility. To examine the nanoscale organization of perinuclear vimentin, we acquired high-resolution electron microscopy volumes of a vitreously frozen cell and reconstructed VIFs and microtubules within a [~]50 {micro}m3 window. Of 583 VIFs identified, most were integrated into long, semi-coherent bundles that fluctuated in width and filament packing density. Unexpectedly, VIFs displayed minimal local co-alignment with microtubules, save for sporadic cross-over sites that we predict facilitate cytoskeletal crosstalk. Overall, this work demonstrates single VIF dynamics and organization in the cellular milieu for the first time SummarySingle-particle tracking demonstrates that individual filaments in bundles of vimentin intermediate filaments are transported in the cytoplasm by motor proteins along microtubules. Furthermore, using 3D FIB-SEM the authors showed that vimentin filament bundles are loosely packed and co-aligned with microtubules.

cell biology↗

bioRxiv2024

Maximizing photon utilization in spectroscopic single-molecule localization microscopy using symmetrically dispersed dual-wedge prisms

Single-molecule localization microscopy (SMLM) enables super-resolution imaging on conventional fluorescent microscopes. Spectroscopic SMLM (sSMLM) further allows highly multiplexed super-resolution imaging. We report an easy-to-implement symmetrically dispersed dual-wedge prism (SDDWP)-sSMLM design that maximizes photon utilization. We first symmetrically dispersed photons to the -1st and +1st orders in an optical assembly using two identical dual-wedge prisms (DWPs). Then we computationally extracted the fluorophores spatial position and spectral characteristics using photons in both the -1st and +1st orders. Theoretical analysis and experimental validation showed lateral and spectral precisions of 10.1 nm and 0.3 nm, respectively, representing improvements of 28% and 48% over our previous DWP-based system, where emitted photons are divided separately for spatial and spectral analyses.

bioengineering↗

bioRxiv2023

Physically informed Monte Carlo simulation of dual-wedge prism-based spectroscopic single-molecule localization microscopy

SignificanceThe dual-wedge prism (DWP)-based spectroscopic single-molecule localization microscopy (sSMLM) system offers improved localization precision and adjustable spectral or localization performance, but its nonlinear spectral dispersion presents a challenge. A systematic method can help understand the challenges and thereafter optimize the DWP systems performance by customizing system parameters to maximize spectral or localization performance for various molecular labels. AimWe developed an MC-based model which predicts the imaging output of the DWP-based sSMLM system given different system parameters. ApproachWe assessed our MC models localization and spectral precisions by comparing our simulation against theoretical equations and fluorescent microspheres. Furthermore, we simulated the DWP-based system using beamsplitters of Reflectance (R):Transmittance (T) of R50:T50 and R30:T70 and their tradeoffs. ResultsOur MC simulation showed average deviations of 2.5 nm and 2.1 nm for localization and spectral precisions against theoretical equations; and 2.3 nm and 1.0 nm against fluorescent microspheres. An R30:T70 beamsplitter improved spectral precision by 8% but worsened localization precision by 35% on average compared to an R50:T50 beamsplitter. ConclusionsThe MC model accurately predicted localization precision, spectral precision, spectral peaks, and spectral widths of fluorescent microspheres, as validated by experimental data. Our work enhances the theoretical understanding of DWP-based sSMLM for multiplexed imaging, enabling performance optimization.

bioengineering↗

bioRxiv2022

Experimental Parameters-Based Monte-Carlo Simulation of Single-Molecule Localization Microscopy of Nuclear Pore Complex to Evaluate Clustering Algorithms

Single-molecule localization microscopy (SMLM) enables the detailed visualization of nuclear pore complexes (NPC) in vitro with sub-20 nm resolution. However, it is challenging to translate the localized coordinates in SMLM images to NPC functions because different algorithms to cluster localizations as individual NPCs can be biased without ground truth for validation. We developed a Monte-Carlo simulation to generate synthetic SMLM images of NPC and used the simulated NPC images as the ground truth to evaluate the performance of six clustering algorithms. We identified HDBSCAN as the optimal clustering algorithm for NPC counting and sizing. Furthermore, we compared the clustering results between the experimental and synthetic data for NUP133, a subunit in the NPC, and found them to be in good agreement.

bioinformatics↗