Unlocking the molecular mechanisms behind our sense of touch

Abstract

Molecular biologists don’t typically conduct their research knee deep in muck, checking underground traps for an elusive mole. But Diana Bautista needed those moles to help her understand the mysterious underpinnings of humans’ sense of touch. “The mechanisms that drive mechanical hypersensitivity and mechanical sensing have been really, a big black box in the field,” says Bautista, an associate professor of cell and developmental biology at University of California, Berkeley. The genes of the star-nosed mole and its remarkable, nerve-fiber–packed nose could point to molecular mechanisms underlying the enigmatic sense of touch. Image courtesy of ScienceSource/Gary Meszaros. Bautista’s quarry, the star-nosed mole, offers a rare opportunity to study a sense of touch few other creatures possess. The mole’s centimeter-sized touch organ (the star of tentacles on its face) is bedecked with 100,000 nerve fibers, called mechanonociceptors. That is five times the number of fibers on a human hand (1). Mechanonociceptors are the first step in the journey of sending a touch signal to the brain. And the genes of this peculiar mole and its nerve fiber-packed nose could point to molecular mechanisms underlying the enigmatic sense of touch. Scientists are on the hunt for the ion channels or any signaling molecules involved in touch sensation. Thus far, these discoveries provide only a small window into the complex machinery of mechanosensation. Still, any step closer to mastering the circuitry that controls mechanical pain is a welcome development for patients and physicians overly reliant on potentially addictive opioids. And mechanosensation research goes far beyond touch and pain. Scientists are discovering that mechanosensory channels play a crucial role in the very function of internal organs. A basic understanding of the sense of touch has been elusive and for good reason. Unlike other senses, touch receptors are not limited to one location in the …