In the lab of Dr. Isabelle Vernos at the Center for Genomic Regulation in Barcelona, Spain I investigated microtubule dynamics during cell division. My project focused on determining key players in the regulation and organization of acentrosomal asters. Acentrosomal asters are small populations of microtubules that are nucleated on or around the condensed chromosomes at the beginning of mitosis. I was interested in determining if the mitotic kinesins and dynein played a role in nucleation, stabilization and/or organization of the acentrosomal asters. To address this question, I set up and preformed an RNAi screen of 10 different motors. Using a microtubule regrowth assay, I observed the nucleation and formation of acentrosomal asters through immunofluorescence and confocal time-lapse imaging. I found motors that seemed to affect microtubule nucleation or stabilization, microtubule polymerization, and microtubule organization. These experiments revealed a possible novel role for motor proteins during mitosis.
In addition to this cell work I learned how to harvest Xenopus laevis extracts, how to deplete key mitotic regulators from the extract and how to induce the formation of spindles in these extracts, in order to probe how key mitotic factors regulate microtubules dynamics and spindle formation.
MT regrowth during mitosis
- DAPI- Tubulin -Kif2a-