2025/10/08 – Peter Van Blerkom

Peter Van Blerkom
Researcher
UC Santa Barbara

Date and time: October 8th, 2025 Wednesday at 8am PST / 11am EST / 4pm GMT / 5pm CET / 12am China

For the zoom links, please join the One World Cryo-EM mailing list.

The GoldX Fiducial Eraser

Gold nanoparticles are standard fiducial markers in cryogenic electron tomography but often cause reconstruction artifacts due to their high electron density. We present a post-processing tool that automatically detects and suppresses these particles by replacing them with the local background. The method yields cleaner tomograms without loss of sample information or introduction of new artifacts, enabling more accurate visualization and interpretation of native cellular structures. 

References:
Van Blerkom P, Bezault A, Sauvanet C, Hanein D, Volkmann N. The GoldX Fiducial Eraser. International Journal of Molecular Sciences. 2024; 25(13):7442. https://doi.org/10.3390/ijms25137442

2024/10/02 – Niels Volkmann

Niels Volkmann
Professor of Electrical and Computer Engineering
UC Santa Barbara

Date and time: October 2th, 2024 Wednesday, at 8am PDT / 11am EDT / 4pm BST / 5pm CEST / 11pm China CST

For the zoom links, please join the One World Cryo-EM mailing list.

High(er) throughput analysis of actin-filament structures in cellular tomograms

The actin cytoskeleton plays a key role in cell migration and morphology in eukaryotic cells. Its diverse architectures enable functions such as protrusion, adhesion, contraction, and retraction. Analyzing cryo-ET data presents challenges due to low signal-to-noise ratios, stemming from weak contrast between biomolecules and the surrounding medium, as well as low electron doses to prevent sample damage. Current methods, such as analyzing vectorized actin filament traces or subtomogram averaging, have provided detailed insights into cytoskeletal structures but do not scale well for large datasets. In this talk, I will present alternative higher-throughput methods we developed for extracting nanoscale actin-filament parameters from hundreds of tomograms.