Redefining the concept of protease-activated receptors: cathepsin S evokes itch via activation of Mrgprs

Sensory neurons that mediate histamine-independent itch express Mas-related G protein coupled receptors (Mrgprs). Here, Reddy et al. show that the cysteine protease cathepsin S cleaves and activates MrgpcrC11 without the generation of a tethered ligand, in contrast to other protease activated receptors.