Directed evolution together with next generation genomics tools

One of the most important events in cell division is the equal segregation of duplicated chromosomes to daughter cells. This process is called anaphase and must be coordinated precisely such that chromosomes divide at the right time (after DNA synthesis is complete and the cell is the correct size & shape) and to the right place (one sister chromatid to each cell; in humans this means keeping track of 46 pairs of duplicated chromatids). Errors in anaphase are of central importance in cancer progression (anneuploidy is a major contributor to cancer evolution) and in developmental diseases such as Down syndrome.

The circuits that control the equal division of chromosomes at anaphase are not fully understood. Our previous work has developed excellent single celled microscopy assays and biochemical approaches to study anaphase control (see Nature 2008). We will build on these efforts and take advantage of affordable whole-genome sequencing technologies to learn new aspects of anaphase control.

The approach will be to focus a strong selective pressure on the process of anaphase. Cells can only survive if they obtain mutations that alter their anaphase control networks quantitatively. We can resequence the genomes of our evolved cells to identify mutations that increase the robustness of anaphase control. We can then isolate each mutation and carefully analyse its effect in vivo.