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bioRxiv · 10.1101/2022.02.17.480955

In situ architecture of human kinetochore-microtubule interface visualized by cryo-electron tomography

Zhao, W.·Jensen, G. J.
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Abstract

Faithful segregation of chromosomes during mitosis relies on a carefully coordinated and intricate interplay between the centromere, kinetochore, and spindle microtubules. Despite its importance, the architecture of this interface remains elusive. Here we used in situ cryo-electron tomography to visualize the native architecture of the kinetochore-microtubule interface in human U2OS cells at different stages of mitosis. We find that the centromere forms a pocket-like structure around kinetochore microtubules. Two morphologically distinct fibrillar densities form end-on and side-on connections to the plus-ends of microtubules within this centromeric pocket. Our data suggest a dynamic kinetochore-microtubule interface with multiple interactions between outer kinetochore components and spindle microtubules.

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Zhao, W., Jensen, G. J.. 2022-02-18. In situ architecture of human kinetochore-microtubule interface visualized by cryo-electron tomography. https://doi.org/10.1101/2022.02.17.480955

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