Summary information and primary citation
- PDB-id
-
7r5r;
DSSR-derived features in text and
JSON formats
- Class
- cell cycle
- Method
- cryo-EM (2.44 Å)
- Summary
- Structure of the human ccan cenp-a alpha-satellite
complex
- Reference
-
Yatskevich S, Muir KW, Bellini D, Zhang Z, Yang J,
Tischer T, Predin M, Dendooven T, McLaughlin SH, Barford
D (2022): "Structure
of the human inner kinetochore bound to a centromeric
CENP-A nucleosome." Science,
376, 844-852. doi: 10.1126/science.abn3810.
- Abstract
- Kinetochores assemble onto specialized centromeric
CENP-A (centromere protein A) nucleosomes
(CENP-A<sub>Nuc</sub>) to mediate attachments
between chromosomes and the mitotic spindle. We describe
cryo-electron microscopy structures of the human inner
kinetochore constitutive centromere associated network
(CCAN) complex bound to CENP-A<sub>Nuc</sub>
reconstituted onto α-satellite DNA. CCAN forms edge-on
contacts with CENP-A<sub>Nuc</sub>, and a
linker DNA segment of the α-satellite repeat emerges from
the fully wrapped end of the nucleosome to thread through
the central CENP-LN channel that tightly grips the DNA. The
CENP-TWSX histone-fold module further augments DNA binding
and partially wraps the linker DNA in a manner reminiscent
of canonical nucleosomes. Our study suggests that the
topological entrapment of the linker DNA by CCAN provides a
robust mechanism by which kinetochores withstand both
pushing and pulling forces exerted by the mitotic
spindle.
