EMD-20839

Single-particle
2.7 Å
EMD-20839 Deposition: 17/10/2019
Map released: 06/11/2019
Last modified: 15/05/2024
Overview 3D View Sample Experiment Validation Volume Browser Additional data Links
Overview 3D View Sample Experiment Validation Volume Browser Additional data Links

EMD-20839

Structure of a Yeast Centromeric Nucleosome at 2.7 Angstrom resolution

EMD-20839

Single-particle
2.7 Å
EMD-20839 Deposition: 17/10/2019
Map released: 06/11/2019
Last modified: 15/05/2024
Overview 3D View Sample Experiment Validation Volume Browser Additional data Links
Sample Organism: Kluyveromyces lactis (strain ATCC 8585 / CBS 2359 / DSM 70799 / NBRC 1267 / NRRL Y-1140 / WM37), unidentified, Saccharomyces cerevisiae (strain ATCC 204508 / S288c)
Sample: Yeast Centromeric Nucleosome
Fitted models: 6uph (Avg. Q-score: 0.623)

Deposition Authors: Migl D, Kschonsak M
Cryoelectron Microscopy Structure of a Yeast Centromeric Nucleosome at 2.7 angstrom Resolution.
Migl D, Kschonsak M, Arthur CP, Khin Y, Harrison SC, Ciferri C, Dimitrova YN
(2020) Structure , 28 , 363 - 370.e3
PUBMED: 32004465
DOI: doi:10.1016/j.str.2019.12.002
ISSN: 0969-2126
ASTM: STRUE6
Abstract:
Kinetochores mediate chromosome segregation during cell division. They assemble on centromeric nucleosomes and capture spindle microtubules. In budding yeast, a kinetochore links a single nucleosome, containing the histone variant Cse4CENP-A instead of H3, with a single microtubule. Conservation of most kinetochore components from yeast to metazoans suggests that the yeast kinetochore represents a module of the more complex metazoan arrangements. We describe here a streamlined protocol for reconstituting a yeast centromeric nucleosome and a systematic exploration of cryo-grid preparation. These developments allowed us to obtain a high-resolution cryoelectron microscopy reconstruction. As suggested by previous work, fewer base pairs are in tight association with the histone octamer than there are in canonical nucleosomes. Weak binding of the end DNA sequences may contribute to specific recognition by other inner kinetochore components. The centromeric nucleosome structure and the strategies we describe will facilitate studies of many other aspects of kinetochore assembly and chromatin biochemistry.