
==== Front
bioRxiv
BIORXIV
bioRxiv
2692-8205
Cold Spring Harbor Laboratory

10.1101/2024.08.27.609789
preprint
1
Article
Temporally discordant chromatin accessibility and DNA demethylation define short and long-term enhancer regulation during cell fate specification
Guerin Lindsey N. http://orcid.org/0000-0002-2070-4481

Scott Timothy J.
Yap Jacqueline A.
Johansson Annelie
Puddu Fabio
Charlesworth Tom
Yang Yilin http://orcid.org/0009-0000-9869-4044

Simmons Alan J.
Lau Ken S. http://orcid.org/0000-0001-8438-0319

Ihrie Rebecca A. http://orcid.org/0000-0003-0439-0141

Hodges Emily http://orcid.org/0000-0001-6513-610X

27 8 2024
2024.08.27.609789https://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/10.1101/2024.08.27.609789
nihpp-2024.08.27.609789.pdf
SUMMARY

Epigenetic mechanisms govern the transcriptional activity of lineage-specifying enhancers; but recent work challenges the dogma that joint chromatin accessibility and DNA demethylation are prerequisites for transcription. To understand this paradox, we established a highly-resolved timeline of DNA demethylation, chromatin accessibility, and transcription factor occupancy during neural progenitor cell differentiation. We show thousands of enhancers undergo rapid, transient accessibility changes associated with distinct periods of transcription factor expression. However, most DNA methylation changes are unidirectional and delayed relative to chromatin dynamics, creating transiently discordant epigenetic states. Genome-wide detection of 5-hydroxymethylcytosine further revealed active demethylation begins ahead of chromatin and transcription factor activity, while enhancer hypomethylation persists long after these activities have dissipated. We demonstrate that these timepoint specific methylation states predict past, present and future chromatin accessibility using machine learning models. Thus, chromatin and DNA methylation collaborate on different timescales to mediate short and long-term enhancer regulation during cell fate specification.
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pmc
