@article {692706,
	title = {Three-dimensional structure of kinetochore-fibers in human mitotic spindles},
	journal = {eLife},
	year = {2022},
	abstract = {
	During cell division, kinetochore microtubules (KMTs) provide a physical linkage between the chromosomes and the rest of the spindle. KMTs in mammalian cells are organized into bundles, so-called kinetochore-fibers (k-fibers), but the ultrastructure of these fibers is currently not well characterized. Here, we show by large-scale electron tomography that each k-fiber in HeLa cells in metaphase is composed of approximately nine KMTs, only half of which reach the spindle pole. Our comprehensive reconstructions allowed us to analyze the three-dimensional (3D) morphology of k-fibers and their surrounding MTs in detail. We found that k-fibers exhibit remarkable variationin circumference and KMT density along their length, with the pole-proximal side showing a broad- ening. Extending our structural analysis then to other MTs in the spindle, we further observed that the association of KMTs with non-KMTs predominantly occurs in the spindle pole regions. Our 3D reconstructions have implications for KMT growth and k-fiber self-organization models as coveredin a parallel publication applying complementary live-cell imaging in combination with biophysical modeling (Conway et al., 2022). Finally, we also introduce a new visualization tool allowing an inter- active display of our 3D spindle data that will serve as a resource for further structural studies on mitosis in human cells.

},
	author = {Robert Kiewisz and Gunar Fabig and Conway, William and Daniel Baum and Needleman, Daniel and M{\"u}ller-Reichert, Thomas}
}
