Epithelial cell extrusion at a glance.

The robustness and plasticity of epithelial tissues rely on the capacity of such tissues to eliminate cells without affecting their sealing. This is achieved by epithelial cell extrusion - a well-orchestrated series of remodelling steps involving the eliminated cell and its neighbours - which ensures the constant maintenance of mechanical and chemical barrier properties while allowing cell expulsion. In this Cell Science at a Glance and the accompanying poster, we describe the remodelling steps that take place within dying or extruding cells, as well as neighbouring cells, outlining the commonalities and variations between tissues and organisms. These steps include reorganization of the cytoskeleton and remodelling of cell-cell junctions that alters their contribution to mechanical coupling and mechanotransduction. We also discuss larger-scale coordination between cells and the contribution of cell extrusion to tissue morphogenesis, epithelial surveillance mechanisms, and pathologies such as cancer and chronic inflammation. Altogether, we outline the complexity and plasticity of this minimalist morphogenetic process.