8OW0

Cryo-EM structure of CBF1-CCAN bound topologically to a centromeric CENP-A nucleosome

Summary for 8OW0

• Entry DOI: 10.2210/pdb8ow0/pdb
• EMDB information: 17226
• Descriptor: C0N3 DNA, Inner kinetochore subunit MCM22, Inner kinetochore subunit IML3, ... (20 entities in total)
• Functional Keywords: kinetochore, point centromere, cenp-a nucleosome, topological entrapment, centromeric dna, cell cycle
• Biological source: Saccharomyces cerevisiae (baker's yeast); More
• Total number of polymer chains: 25
• Total formula weight: 787725.54

Authors

Dendooven, T.D.,Zhang, Z.,Yang, J.,McLaughlin, S.,Schwabb, J.,Scheres, S.,Yatskevich, S.,Barford, D. (deposition date: 2023-04-26, release date: 2023-08-09, Last modification date: 2024-07-24)

Primary citation

Dendooven, T.,Zhang, Z.,Yang, J.,McLaughlin, S.H.,Schwab, J.,Scheres, S.H.W.,Yatskevich, S.,Barford, D.
Cryo-EM structure of the complete inner kinetochore of the budding yeast point centromere.
Sci Adv, 9:eadg7480-eadg7480, 2023

PubMed Abstract: The point centromere of budding yeast specifies assembly of the large kinetochore complex to mediate chromatid segregation. Kinetochores comprise the centromere-associated inner kinetochore (CCAN) complex and the microtubule-binding outer kinetochore KNL1-MIS12-NDC80 (KMN) network. The budding yeast inner kinetochore also contains the DNA binding centromere-binding factor 1 (CBF1) and CBF3 complexes. We determined the cryo-electron microscopy structure of the yeast inner kinetochore assembled onto the centromere-specific centromere protein A nucleosomes (CENP-A). This revealed a central CENP-A with extensively unwrapped DNA ends. These free DNA duplexes bind two CCAN protomers, one of which entraps DNA topologically, positioned on the centromere DNA element I (CDEI) motif by CBF1. The two CCAN protomers are linked through CBF3 forming an arch-like configuration. With a structural mechanism for how CENP-A can also be linked to KMN involving only CENP-QU, we present a model for inner kinetochore assembly onto a point centromere and how it organizes the outer kinetochore for chromosome attachment to the mitotic spindle.

PubMed: 37506202
DOI: 10.1126/sciadv.adg7480

Experimental method

ELECTRON MICROSCOPY (3.4 Å)