Kinetochores and Microtubules Wed without a Ring

Proper chromosome segregation in mitosis requires tethering of spindle microtubules to the kinetochore. Using electron tomography of mammalian cells, McIntosh et al. (2008) now report the presence of fibrils that connect the inner kinetochore to the curved protofilaments at microtubule ends, suggesting a new model for force generation in chromosome movement