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bioRxiv · 10.1101/2020.06.01.127795

Tension promotes kinetochore-microtubule release in response to Aurora B activity

Chen, G.-Y.·Renda, F.·Zhang, H.·Gokden, A.·Wu, D. Z.·Chenoweth, D. M.·Khodjakov, A.·Lampson, M.
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Abstract

Aurora B kinase regulates kinetochore-microtubule interactions to ensure accurate chromosome segregation in cell division. Tension provides a signal to discriminate attachment errors from bi-oriented kinetochores with sisters correctly attached to opposite spindle poles. Current models focus on tension as an input to locally regulate Aurora B activity. Here we show that the outcome of Aurora B activity depends on tension. Using an optogenetic approach to manipulate Aurora B at individual kinetochores, we find that kinase activity promotes microtubule release when tension is high. Conversely, when tension is low, Aurora B activity promotes depolymerization of kinetochore-microtubule bundles while maintaining attachment. We propose that tension is a signal inducing distinct error-correction mechanisms, with release or depolymerization advantageous for typical errors characterized by high or low tension, respectively.

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Chen, G.-Y., Renda, F., Zhang, H., Gokden, A., Wu, D. Z., Chenoweth, D. M., Khodjakov, A., Lampson, M.. 2020-06-02. Tension promotes kinetochore-microtubule release in response to Aurora B activity. https://doi.org/10.1101/2020.06.01.127795

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