Understanding structure-function relationships with single-molecule statistics is crucial for a variety of fields including intra- and extra-cellular transport in live biological systems. In such systems, it would be attractive to achieve high throughput 3D dynamic information in addition to high-resolution spatial images of cellular organelles. We have designed and built a novel three-color widefield fluorescence microscope for tracking dynamics in 3D while imaging structures of cellular organelles at various depths within the cell. Multi-color, 3D images are acquired with a single camera while one color provides dynamic axial detail through phase engineering in the Fourier plane. We used this microscope to understand the complex transport of cholera toxin-B (CTxB) around the Golgi apparatus inside live baby hamster kidney (BHK) cells. The Golgi apparatus and the nucleus of the live BHK cells are fluorescently tagged and imaged at various ‘z’ depths to relate their structures and positions relative to the CTxB carrying endosome trajectories. Our study quantifies heterogeneous transport behavior, especially the active transport processes of CTxB when compared to the transport inhibitory drug-treated BHK cells. We find that the active transport process of the CTxB inside endosomes is restricted and the overall displacement of the toxins reduces in drug-treated conditions.

Reduced directed transport of cholera toxin B (CTxB) inside brefeldin A treated live BHK cells measured with phase-engineered 3D tracking and multi-color z-stack imaging

Fall 2022 abstracts, posters, and presentations will launch in mid-September.

ACS Fall 2022

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.