Periodic Reporting for period 2 - Self-Control (Interplay between genetic control and self-organization during embryo morphogenesis)
Période du rapport: 2020-05-01 au 2021-10-31
This project addresses the fundamental property of living matter to be organized, that is to say, to acquire a form to support a function. Tissues that loose the capacity to control their form are functionally perturbed, as in cancers and many other diseases. Biological organisation is a keystone feature of all living matter accross scales from molecular assemblies, cells, to organisms and ecosystems. Understanding what underlies this is a major challenge that requires expertise from different disciplines.
We study here the form of biological tissues and what underlies acquisition of specific forms. We are interested in how mechanical forces and chemical information exchanged by cells orchestrate the dynamics of cells and thereby tissue shape changes, a process called morphogenesis. In the context of this research project we study two kinds of tissue dynamics: tissue flow and tissue wave. Like in a fluid, activity and deformation can be transported (flow) or propagated (wave) in a tissue.
We address the nature of the mechanical and chemical activities that orchestrate the flow and wave dynamics occurring in embryonic tissues. We also delineate the role of tissue shape (its geometry) in these processes.
We study here the form of biological tissues and what underlies acquisition of specific forms. We are interested in how mechanical forces and chemical information exchanged by cells orchestrate the dynamics of cells and thereby tissue shape changes, a process called morphogenesis. In the context of this research project we study two kinds of tissue dynamics: tissue flow and tissue wave. Like in a fluid, activity and deformation can be transported (flow) or propagated (wave) in a tissue.
We address the nature of the mechanical and chemical activities that orchestrate the flow and wave dynamics occurring in embryonic tissues. We also delineate the role of tissue shape (its geometry) in these processes.
We have made two important discoveries so far.
First we identified an important mechanochemical signal essential for wave propagation. We found that this signal underlies the propagation of cell deformation as in a domino cascade. The deformation is induced genetically (the trigger of the cascade) and propagates by a combination of mechanical stimulation and chemical excitation (similar to a domina falling on another domino). The process is said to be self-organised because it propagates on its own once triggered.
We also found that tissue curvature is an essential player in tissue flow. The geometry of the embryo (the gradient of its curvature) tells the embryo in which direction to flow, like the shape of a hill tells which direction the water should flow.
First we identified an important mechanochemical signal essential for wave propagation. We found that this signal underlies the propagation of cell deformation as in a domino cascade. The deformation is induced genetically (the trigger of the cascade) and propagates by a combination of mechanical stimulation and chemical excitation (similar to a domina falling on another domino). The process is said to be self-organised because it propagates on its own once triggered.
We also found that tissue curvature is an essential player in tissue flow. The geometry of the embryo (the gradient of its curvature) tells the embryo in which direction to flow, like the shape of a hill tells which direction the water should flow.
Our project requires the expertise of biologists and physicists, experimental scientists and theorists. We developed cutting edge microscopy methods to image the dynamics of cells in 3D, while probing molecular dynamics using fluorescent reporters. We also developed computational model to predict tissue outcomes given experimental input data and a physical model of thee processes we study.
Our project will lead us to a highly quantitative assessment of tissue geometry, mechanics and genetics in driving the process of tissue morphogenesis. We expect to reveal new fundamental features of self-organisation.
Our project will lead us to a highly quantitative assessment of tissue geometry, mechanics and genetics in driving the process of tissue morphogenesis. We expect to reveal new fundamental features of self-organisation.