Pannexin membrane channels are mechanosensitive conduits for ATP

TLDR

Intercellular calcium wave propagation initiated by mechanical stress occurs in nearly all cell types and relies on InsP3 transfer through gap junctions and ATP release onto purinergic receptors, yet the ATP conduit has remained elusive. The study aims to describe the properties of single pannexin 1 channels. The authors investigate single pannexin 1 channels to assess their properties. They exhibit wide expression, large conductance, ATP permeability, and mechanosensitivity, positioning pannexins as candidates for ATP release during mechanical stress.

Abstract

Intercellular calcium wave propagation initiated by mechanical stress is a phenomenon found in nearly all cell types. The waves utilize two pathways: transfer of InsP3 directly from cell to cell through gap junction channels and release of ATP onto extracellular purinergic receptors. The conduit for ATP has remained elusive and both a vesicular and a channel mediated release have been considered. Here, we describe the properties of single pannexin 1 channels. They have a wide expression spectrum, they are of large conductance and permeant for ATP, and they are mechanosensitive. Hence, pannexins are candidates for the release of ATP to the extracellular space upon mechanical stress.