Wound repair is a fundamental process that is required for tissue homeostasis and regeneration following damage. Most studies of wound healing have focussed on changes in the leading edge of wounded cells, but here William Razzell, Will Wood and Paul Martin show that morphogenetic cell shape changes that occur multiple cell rows back from the wound are important for efficient wound re-epithelialisation (p. ). Using laser-induced wounding of the Drosophila embryo epidermis as a model, the researchers first show that multiple rows of cells around the wound stretch towards the closing tissue. They further reveal dramatic shrinking of the cell-cell junctions that are perpendicular to the pulling force of the wound. This shrinking, which is driven by pulses of myosin that are directed to the cell junctions, leads to cell intercalations. Importantly, these morphogenetic changes, which resemble those observed during the developmental event of germband extension, are essential for wound closure; blocking myosin activity in cells behind the leading edge results in delayed wound contraction. This work highlights an important role for cells surrounding the wound in its closure, and suggests that the cellular morphogenetic mechanisms used during development are recapitulated during wound healing.
