Mechanics of cell-cell junctions
How living cells are able to sense their environment and adequately respond in terms of morphology, migration, proliferation, differentiation, and survival remains one of the more puzzling issues in cell biology. This is particularly obvious in the context of embryonic development, where a specific and complex architectural organization of biological tissues is elaborated.
Embryonic cells adhere, migrate, segregate, and differentiate in a selective and coordinated fashion. As histogenesis proceeds, specific cellular junctions are formed, which contribute to the mechanical cohesion of tissues and act as platforms allowing cell communication. Furthermore dysfunctions of cell adhesion frequently lead to the loss of tissue homeostasis, having serious physiopathological consequences such as tumor development and metastasis. It is thus important to understand how, according to their physiological state and position in the embryo or tissue, cells can establish and regulate precise contacts with adjacent cells.
Conversely, one has to understand at the molecular level how cells can interpret “contact” information and transmit chemical and mechanical signals towards the cytoskeleton, the cytoplasm and the nucleus to allow an adapted cellular response. Transduction of mechanical stress is an underestimated cell adhesion-associated signal contributing to morphogenetic movements during development. For example, the traction forces developed and transmitted via integrins by cells toward the extracellular matrix and substratum have been proposed a long time ago and recently characterized in details. The mechanical stress through its effect on cell tension has high incidence on cell migration as well as survival or differentiation
In contrast, very little is known on mechano-transduction at cell-cell contacts. Our objective is to understand how cadherins will transmit mechanical stress, with the aim to better understand the mechanisms involved in the control of normal cell differentiation and its pathological dysfunctions.