UC Berkeley

Mitosis is one of the most dramatic and complex processes in the life of a cell. Although first observed over 100 years ago, there are still many gaps in our understanding of this crucial process. Years of research into the mechanisms of cell division have uncovered many of the protein players required for the faithful execution of this essential process. However, very little is known about the roles of RNAs during mitosis. In my thesis work, I established several biological functions and regulatory modes employed by RNAs and the RNA biogenesis machinery that are essential for cell division. Using a variety of techniques, I showed that RNA biogenesis during mitosis is an essential step in the assembly of the mitotic spindle and mitotic chromatin. I also provided evidence that RNAs are required for microtubule generation, microtubule organization, and chromatin assembly. In addition, I developed automated image analysis tools to systematically assess mitotic spindle morphology for Xenopus egg extract spindle assembly reactions, a very challenging image analysis application. My work suggests that RNAs should be included as a broad class of regulatory molecules that are essential for the execution of eukaryotic cell division.