Modelling and Image Processing of Constriction and Proliferation in the Gastrulation Process of Drosophila melanogaster

International audienceThe initial stage of gastrulation, an early stage of embryogenesis, is called invagination, or primitive streak formation. In the first part of the paper, we analyse by using image processing techniques the cell deformation and motion in the Drosophila melanogaster embryo searching to delimit the first period of invagination without proliferation. Then, in a second part, we propose a biomechanical model, based only on the consideration of elastic and contractile forces exerted on cell walls and on the centrosome through the combination of myosin contraction and cytoskeleton rigidity. Numerical simulations of this model made during the period of gastrulation without proliferation suggest that the model adequately simulates in-vivo cell behaviour, showing the start of the streak formation at the two extremities of the embryo cylinder, followed by a propagation of the invagination to its central part