Mammalian kinetochore-fibers regulate their length and dynamics individually, independent of spindle poles

Abstract

At each cell division, the spindle builds itself from tubulin building blocks, with nanometer-scale components giving rise to a micron-scale structure. While many proteins modulating mammalian spindle length are known, how they work together to set spindle length remains poorly understood. To probe the role of spindle architecture in setting the length of spindle substructures, and vice versa, we inhibit dynein to generate spindles whose kinetochore-fibers (k-fibers) no longer focus and connect at poles.