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bioRxiv · 10.1101/2021.11.29.470303

Asgard ESCRT-III and VPS4 reveal evolutionary conserved chromatin binding properties of the ESCRT machinery

Nachmias, D.·Melnikov, N.·Zorea, A.·De-picchoto, Y.·Zarivach, R.·Mizrahi, I.·Elia, N.
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Abstract

The ESCRT machinery drive membrane remodeling in numerous processes in eukaryotes. Genes encoding for ESCRT proteins have been identified in Asgard archaea, a newly discovered superphylum, currently recognized as the ancestor of all eukaryotes. This begs the question of the functional evolutionary origin of this machinery and its conservation across lineages. Here, we find that Asgard-ESCRTs exhibit conserved DNA-binding properties, which is derived from recruitment of specific members. We show that Asgard-ESCRT-III/VPS4 homologs interact with one another inside mammalian cells, associate with chromatin, and recruit their counterparts to organize in discrete foci in the mammalian nucleus. This is congruent with human-ESCRT-III homologs. We find that human- and Asgard-ESCRT-IIIs associate with chromatin via the same N terminal domain, and that human-ESCRT-III can recruit Asgard-VPS4 to the nucleus to form foci. Therefore, ESCRTs possess chromatin binding properties that were preserved through the billion years of evolution that separate Asgard and human cells.

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Nachmias, D., Melnikov, N., Zorea, A., De-picchoto, Y., Zarivach, R., Mizrahi, I., Elia, N.. 2021-11-29. Asgard ESCRT-III and VPS4 reveal evolutionary conserved chromatin binding properties of the ESCRT machinery. https://doi.org/10.1101/2021.11.29.470303

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