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bioRxiv · 10.1101/2022.06.01.494139

H4K20me1 plays a dual role in transcriptional regulation during regeneration and axispatterning of Hydra

Gungi, A.·Pal, M.·Saha, S.·Galande, S.
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Abstract

The evolution of the first body axis in the animal kingdom and an extensive ability to regenerate makes Hydra, a Cnidarian, an excellent model system for understanding the underlying epigenetic mechanisms. We identify that SETD8 is critical for regeneration due to its interaction with {beta}-catenin to fine-tune the underlying gene regulatory network. Its target histone mark, H4K20me1, colocalizes with transcriptional activation machinery locally at the {beta}-catenin bound TCF/LEF binding sites on the promoters of head-associated genes, marking an epigenetic activation node. Contrastingly, genome-wide analysis of the H4K20me1 occupancy revealed a negative correlation with transcriptional activation. We propose H4K20me1 as a general repressive histone mark in Cnidaria and describe its dichotomous role in transcriptional regulation in Hydra.

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Gungi, A., Pal, M., Saha, S., Galande, S.. 2022-06-01. H4K20me1 plays a dual role in transcriptional regulation during regeneration and axispatterning of Hydra. https://doi.org/10.1101/2022.06.01.494139

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