The spindle is a protein machinery that segregates chromosomes into the daughter cells during cell division. While most of the proteins involved in spindle assembly have been identified, their functions remain largely unknown. As a consequence, a “bottom-up” description of the spindle based on the behavior of individual components is currently not feasible given the large number of components with unknown functions. Instead, I will propose a “top-down” approach, a phenomenological description of the spindle in terms of microtubule organization, density, and stress, that will serve as a framework to map the effects of molecular behaviors to the structure of the spindle. To achieve this goal, I will first present a method based on laser ablation capable of measuring the detailed architecture of spindles. This method reveals that microtubules in Xenopus laevis egg extracts are shortest near poles and become progressively longer towards the center of the spindle. During the second part of the talk I will show that, despite its molecular complexity, the large scale behaviors of the spindle -shape, dynamics and microtubule organization- can be quantitatively described in terms of a phenomenological description containing just a few physically meaningful parameters.


Wednesday, November 18, 2015, 12:00. Seminar Room

Hosted by Prof. Maria Garcia-Parajo