ABOVE: Immunofluorescence image of human tenocytes (cell nuclei in blue, actin in red) with PIEZO1 protein labeled in green (Scale bar: 20 μm)
FABIAN S. PASSINI
The paper
F.S. Passini et al., “Shear-stress sensing by PIEZO1 regulates tendon stiffness in rodents and influences jumping performance in humans,” Nat Biomed Eng, doi:10.1038/s41551-021-00716-x, 2021.
Tendons become stiffer with repeated exercise, particularly when that exercise involves sprinting or jumping. But how they sense and adapt to mechanical forces has long been unclear.
Tackling the problem as a doctoral student at ETH Zurich a few years ago, Fabian Passini studied cells called tenocytes, which sit among the collagen fibers inside tendons. These cells, he found, respond to shear stress (such as occurs when fibers slide past one other as tendons stretch) by letting calcium ions flood in across their membranes.
To investigate how the process is mediated, Passini and colleagues systematically knocked out genes coding for ...
