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bioRxiv · 10.1101/2023.05.11.540353

Centromere Innovations Within a Mouse Species

Gambogi, C. W.·Pandey, N.·Dawicki-McKenna, J. M.·Arora, U. P.·Liskovykh, M. A.·Ma, J.·Lamelza, P.·Larionov, V.·Lampson, M. A.·Logsdon, G. A.·Dumont, B. L.·Black, B. E.
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Abstract

Mammalian centromeres direct faithful genetic inheritance and are typically characterized by regions of highly repetitive and rapidly evolving DNA. We focused on a mouse species, Mus pahari, that we found has evolved to house centromere-specifying CENP-A nucleosomes at the nexus of a satellite repeat that we identified and term {pi}-satellite ({pi}-sat), a small number of recruitment sites for CENP-B, and short stretches of perfect telomere repeats. One M. pahari chromosome, however, houses a radically divergent centromere harboring [~]6 Mbp of a homogenized {pi}-sat-related repeat, {pi}-satB, that contains >20,000 functional CENP-B boxes. There, CENP-B abundance drives accumulation of microtubule-binding components of the kinetochore, as well as a microtubule-destabilizing kinesin of the inner centromere. The balance of pro and anti-microtubule-binding by the new centromere permits it to segregate during cell division with high fidelity alongside the older ones whose sequence creates a markedly different molecular composition. TeaserChromatin and kinetochore alterations arise in response to evolutionarily rapid changes to underlying repetitive centromere DNA.

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Gambogi, C. W., Pandey, N., Dawicki-McKenna, J. M., Arora, U. P., Liskovykh, M. A., Ma, J., Lamelza, P., Larionov, V., Lampson, M. A., Logsdon, G. A., Dumont, B. L., Black, B. E.. 2023-05-13. Centromere Innovations Within a Mouse Species. https://doi.org/10.1101/2023.05.11.540353

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