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bioRxiv
BIORXIV
bioRxiv
2692-8205
Cold Spring Harbor Laboratory

10.1101/2024.09.05.611456
preprint
1
Article
Image-Based Quantitative Single-Cell Method Showed Increase of Global Chromatin Accessibility in Tumor Compared to Normal Cells
Commane Mairead
Jadhav Vidula
Leonova Katerina
Buckley Brian
Withers Henry
Gurova Katerina http://orcid.org/0000-0001-9189-0712

06 9 2024
2024.09.05.611456https://creativecommons.org/licenses/by-nc-nd/4.0/ This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License, which allows reusers to copy and distribute the material in any medium or format in unadapted form only, for noncommercial purposes only, and only so long as attribution is given to the creator.
http://biorxiv.org/lookup/doi/10.1101/2024.09.05.611456
nihpp-2024.09.05.611456.pdf
Abstract

The phenotypic plasticity of cancer cells has recently emerged as an important factor of treatment failure. The mechanisms of phenotypic plasticity are not fully understood. One of the hypotheses is that the degree of chromatin accessibility defines the easiness of cell transitions between different phenotypes. To test this, a method to compare overall chromatin accessibility between cells in a population or between cell populations is needed. We propose to measure chromatin accessibility by fluorescence signal from nuclei of cells stained with DNA binding fluorescent molecules. This method is based on the observations that small molecules bind nucleosome-free DNA more easily than nucleosomal DNA. Thus, nuclear fluorescence is proportional to the amount of nucleosome-free DNA, serving as a measure of chromatin accessibility. We optimized the method using several DNA intercalators and minor groove binders and known chromatin-modulating agents and demonstrated that chromatin accessibility is increased upon oncogene-induced transformation and further in tumor cells.
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pmc
