cells, genes and numbers: measuring and understanding developmental processes in living flies
Looking at living organisms is an ever-ending source of wonders and questions. Looking at embryos under the microscope, we can see cells adopting unique fates at specific times and locations to form tissues and shape embryos with stereotyped sizes, shapes and patterns. Looking at adults, we can see cells and tissues responding to environmental and physiological cues to maintain homeostasis against the insults of time and injuries. How do all these things happen in a stereotyped, hence predictable, manner?
While our research is largely curiosity- and observation-driven, we would like to go beyond observations and try to decipher the inner logic of these living processes. To make this possible, our laboratory is using fruit flies. This organism has been extremely useful to discover many of the important genes that are conserved in all animals, including humans, to build and maintain tissues. In the post-genomic era, fruit flies are very useful to study the fundamental principles of living systems as they provide outstanding tools to examine in a rapid and cost-efficient manner and with unsurpassed temporal and spatial resolutions the effects of controlled perturbations. We are therefore using and developing approaches in genome engineering, microscopy and computational biology to manipulate our flies (mostly through controlled genetic perturbations), to measure the outcome of these perturbations (using fluorescent reporters and quantitative live imaging as well as other cell biological assays) and to model the observed processes (whenever possible).
Currently, we are studying how the early fly embryos gastrulate, how epithelial cells change shape and polarity, how cells divide asymmetrically (see movie below), how cells acquire distinct fates in space and time, how cell-cell interactions organize developing tissues and maintain homeostasis through stem cells and how the regulation of these processes is encoded in the fly genome (see specific projects below).
Movie of a living fly showing neural precursor cells (nucleus in magenta; other nuclei marked in red) undergoing Asymmetric Cell Division: look at the unequal segregation of the protein Numb (green) that is inherited by only one of the two daughters.