Structural basis of nucleosome recognition by the conserved Dsup and HMGN nucleosome-binding motif

Alegrio-Louro, J.; Cruz-Becerra, G.; Kadonaga, J. T.; Leschziner, A. E.

doi:10.1101/2025.01.06.631586

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bioRxiv · 10.1101/2025.01.06.631586

Structural basis of nucleosome recognition by the conserved Dsup and HMGN nucleosome-binding motif

Alegrio-Louro, J.·Cruz-Becerra, G.·Kadonaga, J. T.·Leschziner, A. E.

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Abstract

The tardigrade damage suppressor (Dsup) and vertebrate high mobility group N (HMGN) proteins bind specifically to nucleosomes via a conserved motif whose structure has not been experimentally determined. Here we used cryo-EM to show that both proteins bind to the nucleosome acidic patch via analogous arginine anchors with one molecule bound to each face of the nucleosome. We additionally employed the natural promoter-containing 5S rDNA sequence for structural analysis of the nucleosome. These structures of an ancient nucle-osome-binding motif suggest that there is an untapped realm of proteins with a related mode of binding to chromatin.

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Alegrio-Louro, J., Cruz-Becerra, G., Kadonaga, J. T., Leschziner, A. E.. 2025-01-08. Structural basis of nucleosome recognition by the conserved Dsup and HMGN nucleosome-binding motif. https://doi.org/10.1101/2025.01.06.631586

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