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bioRxiv · 10.1101/2020.05.18.101584

Multidimensional Chromatin Regulation of Cell Lineage Differentiation in a Metazoan Embryo

Zhao, Z.·Fan, R.·Xu, W.·Wang, Y.·Ma, X.·Du, Z.
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Abstract

How chromatin dictates cell differentiation is an intriguing question in developmental biology. Here, a reporter gene integrated throughout the genome was used as a sensor to map the chromatin activity landscape in lineage-resolved cells during C. elegans embryogenesis. Single-cell analysis of chromatin dynamics across critical dimensions of cell differentiation was performed, including lineage, tissue, and symmetry. During lineage progression, chromatin gradually diversifies in general and exhibits switch-like changes following specific cell division, which is predictive of anterior-posterior fate asymmetry. Upon tissue differentiation, chromatin of cells from distinct lineages converge to tissue-specific states but retain "memory" of each cells lineage history, which contributes to intra-tissue heterogeneity. However, cells with a morphologically left-right symmetric organization utilize a predetermination chromatin strategy to program analogous regulatory states in early progenitor cells. Additionally, chromatin co-regulation drives the functional coordination of the genome. Collectively, this work reveals the role of multidimensional chromatin regulation in cell differentiation.

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Zhao, Z., Fan, R., Xu, W., Wang, Y., Ma, X., Du, Z.. 2020-05-19. Multidimensional Chromatin Regulation of Cell Lineage Differentiation in a Metazoan Embryo. https://doi.org/10.1101/2020.05.18.101584

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