Spatiotemporal dynamics of PIEZO1 localization controls keratinocyte migration during wound healing.

The skin is the largest organ of the body. It enables touch sensation and protects against external insults. Wounding of the skin exposes the body to an increased risk of infection, disease and scar formation. During wound healing, the cells in the topmost layer of the skin, called keratinocytes, move in from the edges of the wound to close the gap. This helps to restore the skin barrier. Previous research has shown that the mechanical forces experienced by keratinocytes play a role in wound closure. Several proteins, called mechanosensors, perceive these forces and instruct the cells what to do. Until now, it was unclear what kind of mechanosensors control wound healing. To find out more, Holt et al. studied a recently discovered mechanosensor (for which co-author Ardem Pataputian received the Nobel Prize in 2021), called Piezo1, using genetically engineered mice. The experiments revealed that skin wounds in mice without Piezo1 in their keratinocytes healed faster than mice with normal levels of Piezo1. In contrast, skin wounds of mice with increased levels of Piezo1 in their keratinocytes healed slower than mice with normal levels of Piezo1. The same pattern held true for keratinocytes grown in the laboratory that had been treated with chemicals to increase the activity of Piezo1. To better understand how Piezo1 slows wound healing, Holt et al. tracked its location inside the keratinocytes. This revealed that the position of Piezo1 changes over time. It builds up near the edge of the wound in some places, and at those regions makes the cells move backwards rather than forwards. In extreme cases, an increased activity of Piezo1 can cause an opening of the wound instead of closing it. These findings have the potential to guide research into new wound treatments. But first, scientists must confirm that blocking Piezo1 would not cause side effects, like reducing the sensation of touch. Moreover, it would be interesting to see if Piezo1 also plays a role in other important processes, such as development or certain diseases.