Age-Dependent Plasticity Of Somatosensory Mechanosensation

Somatosensory Mechanosensation remains to be the least understood sensory system in vertebrates. It requires the activation of specialised neurons which innervate the skin and internal organs. A subset of these dorsal root ganglion neurons express Piezo2, which has recently been found to be a key player in the senses of touch and proprioception. This ion channel accomplishes mechanotransduction - the conversion of mechanical stimuli into electrical signals. Tactile sensitivity in humans is subject to regulation and aging processes. Moreover, it is altered in diverse pain conditions and autism spectrum disorders. In this line, we set out to investigate whether tactile sensitivity changes with maturation and aging in healthy mice. Indeed, we found a significant decrease of both Piezo2-mediated mechanically activated currents in dorsal root ganglion neurons in vitro and hind paw mechanosensitivity in vivo with age. This plasticity in somatosensory mechanosensation has previously been unreported and poses an optimal model for studying the molecular underpinnings of age-dependent regulation of somatosensory mechanotransduction as well as Piezo2 function.