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

ABSTRACT: Sensory neurons expressing Mas-related G-protein-coupled receptors (Mrgprs) mediate histamine-independent itch. We show that the cysteine protease cathepsin S activates MrgprC11 and evokes receptor-dependent scratching in mice. In contrast to its activation of conventional protease-activated receptors, cathepsin S-mediated activation of MrgprC11 did not involve the generation of a tethered ligand. We demonstrate further that different cysteine proteases selectively activate specific mouse and human Mrgpr family members. This expansion of our understanding by which proteases interact with G-protein-coupled receptors (GPCRs) redefines the concept of what constitutes a protease-activated receptor. The findings also implicate proteases as ligands to members of this orphan receptor family while providing new insights into how cysteine proteases contribute to itch.

SUBMITTER: Reddy VB

PROVIDER: S-EPMC4520244 | biostudies-literature | 2015 Jul

REPOSITORIES: biostudies-literature

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

Reddy Vemuri B VB Sun Shuohao S Azimi Ehsan E Elmariah Sarina B SB Dong Xinzhong X Lerner Ethan A EA

Nature communications 20150728

Sensory neurons expressing Mas-related G-protein-coupled receptors (Mrgprs) mediate histamine-independent itch. We show that the cysteine protease cathepsin S activates MrgprC11 and evokes receptor-dependent scratching in mice. In contrast to its activation of conventional protease-activated receptors, cathepsin S-mediated activation of MrgprC11 did not involve the generation of a tethered ligand. We demonstrate further that different cysteine proteases selectively activate specific mouse and hu ...[more]

PMID: 26216096

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