Figure 2. Kinetochores laterally bind stabilised MT bundles in the absence of K-fibres.
HeLa cells in control (a), HSET (b), hNuf2 (c), or hNuf2+HSET (d) RNAi were treated with 0.2 mM CaCl2 to depolymerise highly dynamic MTs and stained to visualise MTs (red), kinetochores (ACA, green) and DNA (blue). Scale bar, 10 µm for whole spindle images (left) or 1 µm for insets (right). Arrowheads indicate a MT bundle that transverses the spindle equator without making an end-on attachment to a kinetochore. (e) Correlative light/serial section EM was performed in hNuf2+HSET RNAi cells. Low magnification view of a cell showing the spindle equator region. (f) Higher magnification view of the region boxed in panel (e). Notice a bundle of microtubules bypassing kinetochores.
