8COM

Structure of the Nucleosome Core Particle from Trypanosoma brucei

Summary for 8COM

• Entry DOI: 10.2210/pdb8com/pdb
• EMDB information: 16777
• Descriptor: Histone H3, putative, Histone H4, Histone H2A, ... (6 entities in total)
• Functional Keywords: nucleosome chromatin parasite trypanosome kinetoplast, dna binding protein
• Biological source: Trypanosoma brucei brucei TREU927; More
• Total number of polymer chains: 10
• Total formula weight: 194029.82

Authors

Burdett, H.,Deak, G.,Wilson, M.D. (deposition date: 2023-02-28, release date: 2023-07-12, Last modification date: 2023-09-06)

Primary citation

Deak, G.,Wapenaar, H.,Sandoval, G.,Chen, R.,Taylor, M.R.D.,Burdett, H.,Watson, J.A.,Tuijtel, M.W.,Webb, S.,Wilson, M.D.
Histone divergence in trypanosomes results in unique alterations to nucleosome structure.
Nucleic Acids Res., 51:7882-7899, 2023

PubMed Abstract: Eukaryotes have a multitude of diverse mechanisms for organising and using their genomes, but the histones that make up chromatin are highly conserved. Unusually, histones from kinetoplastids are highly divergent. The structural and functional consequences of this variation are unknown. Here, we have biochemically and structurally characterised nucleosome core particles (NCPs) from the kinetoplastid parasite Trypanosoma brucei. A structure of the T. brucei NCP reveals that global histone architecture is conserved, but specific sequence alterations lead to distinct DNA and protein interaction interfaces. The T. brucei NCP is unstable and has weakened overall DNA binding. However, dramatic changes at the H2A-H2B interface introduce local reinforcement of DNA contacts. The T. brucei acidic patch has altered topology and is refractory to known binders, indicating that the nature of chromatin interactions in T. brucei may be unique. Overall, our results provide a detailed molecular basis for understanding evolutionary divergence in chromatin structure.

PubMed: 37427792
DOI: 10.1093/nar/gkad577

Experimental method

ELECTRON MICROSCOPY (3.3 Å)