bioRxiv Science⌕ Search

Biology subjects

Shalev Ezra, Y.

Publications and source records attributed to Shalev Ezra, Y..

2 recordsLinked to original sources

Monitoring DNA double strand break repair in Saccharomyces cerevisiae at high throughput and high resolution

DNA repair is critical for cellular function and genomic stability across organisms. Yeast mating-type switching serves as an established model for studying DNA break repair and chromatin dynamics. However, real-time tracking of mating-type switching in live cells remains challenging due to resolution limitations of existing techniques. Here, we use high-throughput methods, including three-dimensional imaging, to follow the dynamics of DNA damage and repair and to quantify mating-type switching occurrences at the single live cell level, with unprecedented resolution. We reveal chromatin reconfiguration for both single- and double-strand breaks following switching induction. Our findings provide new observation of the correlation between chromatin folding and single-strand breaks.

cell biology↗

High-throughput multicolor 3D localization in live cells by depth-encoding imaging flow cytometry

Imaging flow cytometry replaces the canonical point-source detector of flow cytometry with a camera, unveiling subsample details in 2D images while maintaining high-throughput. Here we show that the technique is inherently compatible with 3D localization microscopy by point-spread-function engineering, namely the encoding of emitter depth in the emission pattern captured by a camera. By exploiting the laminar-flow profile in microfluidics, 3D positions can be extracted from cells or other objects of interest by calibrating the depth-dependent response of the imaging system using fluorescent microspheres mixed with the sample buffer. We demonstrate this approach for measuring fluorescently-labeled DNA in vitro and the chromosomal compaction state in large populations of live cells, collecting thousands of samples each minute. Furthermore, our approach is fully compatible with existing commercial apparatus, and can extend the imaging volume of the device, enabling faster flowrates thereby increasing throughput.

biophysics↗