By moving together, cells find their sense of direction

Many tissues only work if every cell faces the same way — think of the tiny hairs in your inner ear, which must all point one way for sound to register. What first tells a sheet of cells which way to face has long been a mystery. A team in Pulin Li's lab at the Whitehead Institute rebuilt the process in a dish, using engineered skin-like cells with glowing marker proteins, and watched it happen live: when the cells were set moving together, a linking protein called CELSR lined up along each cell's front-to-back axis, the alignment spread to neighbours, and the whole sheet gained a shared sense of direction. The findings, published in the Proceedings of the National Academy of Sciences, give researchers a way to switch this organising step on and study it — a step toward one day growing replacement tissues whose cells point the right way.

SDG 9 · Industry, innovation and infrastructure — Mechanism: tech innovation