Two DOT1 Enzymes Cooperatively Mediate Efficient Ubiquitin-Independent Histone H3 Lysine 76 Tri-Methylation in Kinetoplastids

Authors

Victoria Frisbie, Thomas Jefferson University
Hideharu Hashimoto, Thomas Jefferson UniversityFollow
Yixuan Xie
Francisca De Luna Vitorino
Josue Baeza
Tam Nguyen, Thomas Jefferson UniversityFollow
Zhangerjiao Yuan, Thomas Jefferson UniversityFollow
Janna Kiselar
Benjamin Garcia
Erik Debler, Thomas Jefferson UniversityFollow

Document Type

Article

Publication Date

3-19-2024

Comments

This article is the author's final published version in Nature Communications, Volume 15, Issue 1, 2024, Article number 2467.

The published version is available at https://doi.org/10.1038/s41467-024-46637-6.

Copyright © The Author(s) 2024

Abstract

In higher eukaryotes, a single DOT1 histone H3 lysine 79 (H3K79) methyltransferase processively produces H3K79me2/me3 through histone H2B mono-ubiquitin interaction, while the kinetoplastid Trypanosoma brucei di-methyltransferase DOT1A and tri-methyltransferase DOT1B efficiently methylate the homologous H3K76 without H2B mono-ubiquitination. Based on structural and biochemical analyses of DOT1A, we identify key residues in the methyltransferase motifs VI and X for efficient ubiquitin-independent H3K76 methylation in kinetoplastids. Substitution of a basic to an acidic residue within motif VI (Gx₆K) is essential to stabilize the DOT1A enzyme-substrate complex, while substitution of the motif X sequence VYGE by CAKS renders a rigid active-site loop flexible, implying a distinct mechanism of substrate recognition. We further reveal distinct methylation kinetics and substrate preferences of DOT1A (H3K76me0) and DOT1B (DOT1A products H3K76me1/me2) in vitro, determined by a Ser and Ala residue within motif IV, respectively, enabling DOT1A and DOT1B to mediate efficient H3K76 tri-methylation non-processively but cooperatively, and suggesting why kinetoplastids have evolved two DOT1 enzymes.

Recommended Citation

Frisbie, Victoria; Hashimoto, Hideharu; Xie, Yixuan; De Luna Vitorino, Francisca; Baeza, Josue; Nguyen, Tam; Yuan, Zhangerjiao; Kiselar, Janna; Garcia, Benjamin; and Debler, Erik, "Two DOT1 Enzymes Cooperatively Mediate Efficient Ubiquitin-Independent Histone H3 Lysine 76 Tri-Methylation in Kinetoplastids" (2024). Department of Biochemistry and Molecular Biology Faculty Papers. Paper 253.
https://jdc.jefferson.edu/bmpfp/253

Creative Commons License

This work is licensed under a Creative Commons Attribution 4.0 License.

PubMed ID

38503750

Language

English