Dr Claire Lye

Understanding how tissues are shaped during embryonic growth

During the embryonic growth and development of animals, thousands of cells organise themselves into tissues and organs with a variety of complex shapes. 

I study Drosophila embryos to understand the fundamental mechanisms by which tissues are shaped during embryonic development, a process called morphogenesis.

Studying the forces underlying morphogenesis

To fully understand morphogenesis, we must understand the nature of all the forces involved and how they act together to direct the final shape of a tissue (Lye and Sanson, 2011).  Tissues arise from groups of cells, which undergo collective cell movements to generate the final shape of the tissue.

Cells in the group can generate their own, intrinsic, forces to drive genetically-programmed cell behaviours contributing to collective cell movement. Cells can also respond to physical forces generated elsewhere in the embryo (extrinsic forces), either by deforming passively or responding actively.  I aim to address integration of both genetically-programmed and physical cues during collective cell movement, using Drosophila embryos as a model.

I use genetics, in vivo imaging, cell tracking and computational analysis to analyse in detail how cells move and change shape during morphogenetic movements in order to understand the forces driving these cell behaviours.

Using this approach I have shown that during the convergence and extension of the body axis of Drosophila (germband extension), epithelial cells stretch passively in response to extrinsic tension generated by the invagination of the neighbouring posterior endoderm (Lye et al, 2015 pdf).   This highlights the importance of physical interactions between tissues during morphogenesis.

I have collaborated on a recent study modeling morphogenetic movements at the scale of the whole embryo, which demonstrated the importance of the geometry of the embryo to help guide morphogenetic movements (Dicko et al, 2017 pdf).

Identifying novel proteins involved in morphogenesis

To identify proteins involved in generating the forces underlying morphogenesis, I led a screen of Drosophila exon-trap lines expressing YFP-tagged proteins, which had been generated by the Cambridge Protein Trap Insertion Team (Lowe et al, 2014; website).  The Yellow Fluorescent Protein (YFP) tag allows the proteins to be visualized in living embryos.  We characterized the subcellular localization of 600 YFP-tagged proteins in early Drosophila embryos (Lye et al, 2014 pdf).  Specifically, we identified proteins localizing to the cortex of the cell, which is where the force generating cytoskeleton of the cell resides.  The role of these proteins in morphogenesis is currently being assessed by members of the Sanson lab.

Main Collaborators

My PI -  Dr Bénédicte Sanson

Dr Guy Blanchard

Dr Richard Adams

Dr Jocelyn Étienne

Dr Leila Muresan