When a larval zebrafish twitches its tail, the vascular endothelium lights up with a calcium signal, mediated by Piezo1. We used to think mechanosensing in endothelial cells was about sensing blood flow, but at least in this case it's about sensing body motion.

Did you know that when zebrafish swim, this motion evokes calcium signals in their *blood vessels*? Bill Jia and Xin Tang showed that this effect is mediated by Piezo1, and only requires physical motion, not neural activity or blood flow.