Sedzinski Group
Last updated
Last updated
Development and homeostasis of epithelial sheets depend upon the regular addition of new cells and removal of old cells. The last decade has seen an explosion of interest in the mechanisms governing the homeostatic extrusion or delamination of cells from epithelia. These studies reveal a complex interplay between molecular signals and cell mechanics and underscore the importance of epithelial cell shape in epithelial homeostasis.
Despite the intense focus on actomyosin-generated forces and cell removal from epithelia, the converse process of adding a new cell to an existing epithelium has been largely ignored. This gap in our knowledge is significant because the homeostasis of many epithelial tissues involves adding new cells from basally-located progenitors.
Indeed, such basal stem cells have been described in the airway, olfactory epithelium, cornea, and prostate, among others. In such multilayered tissues, progenitor cells must move apically and insert individually and seamlessly into the epithelial sheet, which must be exquisitely coordinated to maintain epithelial function.