Supervisor: Dr Bénédicte Sanson
We investigate morphogenesis, in other words the mechanisms by which embryos and organs acquire their complex tri-dimensional shapes. To understand morphogenesis, we need to study the role of genetic programs in shaping tissues, but also to consider the physical environment of the embryo, for example how the embryonic architecture imposes stresses or constrains cell behaviours. In our group, working with interdisciplinary collaborators, we strive to consider these two elements together, using a range of approaches, from developmental genetics and confocal imaging to computational analysis of cell behaviours. As a model, we use early Drosophila embryos because they are easy to image live and to manipulate genetically. We work with live embryos labelled with fluorescent proteins to analyse the behaviour of the cytoskeleton, the changes in cell shapes and the movement of cells relative to each other. We are focusing on a window of developmental time spanning from gastrulation to the first signs of segmentation. During this time period, we investigate the conserved morphogenetic processes of axis extension and tissue boundary formation [1-3]. We have recently found that the segmental boundaries are important for cell intercalation and cell segregation during axis extension (Tetley RJ*, Blanchard GB*§, Adams RJ & Sanson B§, “Unipolar distributions of junctional Myosin II identify cell stripe boundaries that drive cell intercalation throughout Drosophila axis extension”, in revision at eLife). One possible project in the lab is to follow-up on this recent discovery, exploring the molecular and physical mechanisms underlying boundary formation during axis extension . Other projects are possible as well, please come and discuss if interested.
 Monier, B., Pellissier-Monier, A. P. E., Brand, A. H., & Sanson, B. (2010). An actomyosin-based barrier inhibits cell mixing at compartmental boundaries in Drosophila embryos. Nature Cell Biology, 12(1), 60–65. http://doi.org/doi:10.1038/ncb2005
 Butler, L. C., Blanchard, G. B., Kabla, A. J., Lawrence, N. J., Welchman, D. P., Mahadevan, L., Adams, R., & Sanson, B. (2009). Cell shape changes indicate a role for extrinsic tensile forces in Drosophila germ-band extension. Nature Cell Biology, 11(7), 859–864. http://doi.org/10.1038/ncb1894
 Lye, C. M., Blanchard, G. B., Naylor, H. W., Mureşan, L., Huisken, J., Adams, R. J., & Sanson, B. (2015). Mechanical coupling between endoderm invagination and axis extension in Drosophila. PLoS Biology, 13(11), e1002292. http://doi.org/10.1371/journal.pbio.1002292
 Review: Fagotto, F. (2014). The cellular basis of tissue separation. Development 141(17), 3303–3318. http://doi.org/10.1242/dev.090332