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bioRxiv · 10.1101/2022.08.17.504347

The centromere/kinetochore is assembled through CENP-C oligomerization

Abstract

The kinetochore is an essential protein complex for accurate chromosome segregation. The constitutive centromere-associated network (CCAN), a subcomplex of the kinetochore, associates with centromeric chromatin providing a platform for the kinetochore assembly. A CCAN protein, CENP-C, is thought to be a central hub for the centromere/kinetochore organization. However, the crucial role of CENP-C in centromeres remains to be elucidated. Here, we demonstrated that both the CCAN-binding domain and C-terminal Cupin domain of CENP-C are necessary and sufficient for chicken CENP-C function. Our structural and biochemical analyses revealed that the Cupin domain of chicken and human CENP-C is self-oligomerization domain, which is crucial for centromeric chromatin organization. CENP-C mutants lacking the oligomerization interface cause mislocalization of CCAN and cell death. Based on these results, we conclude that the CENP-C oligomerization plays a crucial role in centromere function via providing the robust centromeric chromatin in vertebrate cells.

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Hara, M., Ariyoshi, M., Sano, T., Nozawa, R.-s., Shinkai, S., Onami, S., Jansen, I., Hirota, T., Fukagawa, T.. 2022-08-18. The centromere/kinetochore is assembled through CENP-C oligomerization. https://doi.org/10.1101/2022.08.17.504347

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