Project Reference: TRG27-GEN-EC1

Project title: Developmental genetics and evolution of early head patterning in flies

Project outline

The body plan of the model fruit fly, Drosophila melanogaster, is established early in development, while the embryo is a syncytial blastoderm. The anterior third of the blastoderm gives rise to the head and brain, while the remainder of the blastoderm gives rise to the segmented trunk. The patterning of the trunk is much better studied than the patterning of head, being both conceptually simpler and more conducive to genetic analysis. Whereas the patterning of the trunk by gap genes and pair-rule genes is essentially one-dimensional and maps clearly onto the segmented pattern of the larval cuticle, the patterning of the head is two-dimensional at the blastoderm stage and is later distorted by complex morphogenetic rearrangements. As a consequence, the patterning of the head remains poorly understood, although it is clear that the maternal Bicoid gradient plays an important role in activating and coordinating domains of gene expression. Interestingly, the bicoid gene evolved relatively recently, within Diptera (flies), and has subsequently been lost multiple times. Head patterning appears to be quite evolutionarily flexible, contributing to ecological adaptation and insect biodiversity.

The main aim of this project is to characterise the gene regulatory network controlling early head patterning in Drosophila melanogaster. The student will use advanced 10-plex confocal microscopy and computational image analysis to map patterns of gene expression in the anterior blastoderm, and quantify how they are affected by mutations and other genetic perturbations. This data will be used to construct a 2D dynamical model of head patterning, in collaboration with another lab member. A second aim is to expand this analysis to fly species which do not use a Bicoid gradient to pattern their anteroposterior axis. Together, these results will provide new insights into the development of the insect head and brain, and how these processes vary across evolution.

Principal Supervisor

Dr Erik Clark

Email address: ec491@cam.ac.uk

Department / Partner Institute: Genetics

Website: https://www.gen.cam.ac.uk/clark-group

BBSRC strategic theme

Understanding the rules of life