The contribution of cell division to axis extension in insects
Developmental Biology
Final Report Abstract
During animal development, different regions are specified to form different tissues in the adult. This process requires intricate coordination both in space, i.e. how big each tissue will be, but also in time, i.e. when one tissue forms with respect to another. We studied this coordination in the fruit fly, Drosophila melanogaster, by looking at how different segments are formed during development. We found that a single set of genes controls whether segments are made one at a time or many segments at the same time. This set of “timer” genes is itself controlled by a second set of unrelated genes that affect where the timer genes are active in the embryo. We analysed the activity of both sets of genes in normal embryos, and embryos in which we have deactivated (mutated) individual genes. Through this analysis, and computational modelling, we identified how these genes affect each other to make the segments at the right time and place.