mechanosensory

Mechanosensation is the sense by which cells and organisms detect mechanical forces such as pressure, stretch, vibration, and fluid flow. It underpins touch, proprioception, hearing, balance, blood flow sensing, and aspects of vascular regulation. Mechanosensitive transduction starts when a mechanical stimulus deforms the cell membrane or extracellular matrix, leading to the opening of mechanosensitive ion channels and the generation of electrical or chemical signals.

In animals, specialized receptors convey mechanical information. Tactile receptors include Meissner’s corpuscles, Merkel cells, Pacinian corpuscles, and Ruffini endings, each with distinct sensitivities. Proprioceptors in muscles and joints report limb position and movement. Inner-ear hair cells translate deflections of their stereocilia into receptor potentials, enabling hearing and vestibular function. Mechanical stimuli can also activate certain nociceptors, contributing to mechanical pain.

Mechanotransduction often involves mechanosensitive ion channels such as Piezo1 and Piezo2, which respond to membrane tension. Other channels, including certain TRP channels and ENaC/ASIC family members, contribute in specific tissues. Forces are transmitted through the cytoskeleton and extracellular matrix, with tethering mechanisms that influence channel gating and adaptation.

In plants, mechanosensing detects touch, wind, gravity, and osmotic changes. Mechanosensitive channels such as MSL/MscS-like proteins and MCA family members mediate calcium signaling that coordinates growth, thigmomorphogenesis, and rapid movements.

Research on mechanosensation informs neuroscience, physiology, and bioengineering. Defects in mechanotransduction can cause sensory disorders, neuropathic pain, or hearing loss. Piezo-channel modulators and other mechanosensors are explored as therapeutic targets and as inspiration for tactile sensors in robotics.