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bioRxiv · 10.1101/515924

Aurora B-INCENP localization at centromeres/inner kinetochores is essential for chromosome bi-orientation in budding yeast

Garcia-Rodriguez, L. J.·Kasciukovic, T.·Denninger, V.·Tanaka, T. U.
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Abstract

To promote chromosome bi-orientation, Aurora B kinase weakens and disrupts aberrant kinetochore-MT interaction. It has long been debated how Aurora B halts this action when bi-orientation is established and tension is applied across sister kinetochores. Pertinent to this debate, it was shown that Bir1 (yeast Survivin), which recruits Ipl1-Sli15 (yeast Aurora B-INCENP) to centromeres, is dispensable for bi-orientation, raising the possibility that Aurora B localization at centromeres is not required for bi-orientation. Here, we show that the COMA inner kinetochore sub-complex physically interacts with Sli15, recruits Ipl1-Sli15 to the inner kinetochore and promotes chromosome bi-orientation, independently of Bir1, in budding yeast. Moreover, using an engineered recruitment of Ipl1-Sli15 to the inner kinetochore when both Bir1 and COMA are defective, we show that localization of Ipl1-Sli15 at centromeres/inner kinetochores is essential for bi-orientation, refuting the above possibility. Our results give important insight into how Aurora B disrupts kinetochore-MT interaction in a tension-dependent manner, to promote chromosome bi-orientation.

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Garcia-Rodriguez, L. J., Kasciukovic, T., Denninger, V., Tanaka, T. U.. 2019-01-09. Aurora B-INCENP localization at centromeres/inner kinetochores is essential for chromosome bi-orientation in budding yeast. https://doi.org/10.1101/515924

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