Abstract

I am interested in the development of a bipotent population of stem cells called neuromesodermal progenitors. This essential cell population provides a continuous source of spinal cord and mesodermal progenitors during elongation of the posterior body axis. Despite apparent conservation in the expression of key gene regulatory and signalling components that are known to be important for the maintenance of this stem cell population, I have recently shown that there are considerable differences in the cell behaviours that are modulated by these mechanisms across vertebrate species. This depends largely on the degree to which growth occurs concomitantly with the establishment of the body axis. This data will be presented together with a large scale live imaging study of amphioxus gastrulation. Surprisingly, we have found that the cell behaviours driving elongation of the body axis is remarkably simple during these stages, with orientation of cell division being solely responsible for this process. By applying a combination of live imaging and quantitative single-cell gene expression analyses across a range of chordate models, I now aim to further explore the fundamental question of how conserved molecular mechanisms at the the cell population level can drive divergent morphogenetic processes at the level of single cells in order to produce the diverse array of chordate body plans.