By Sophie Zhu
Two scientists have received the 2021 Nobel Prize in Medicine for their discoveries of molecular receptors that detect temperature and touch. Nearly two decades ago, David Julius, a physiologist at the University of California, San Francisco, used capsaicin, the ‘spicy’ compound found in chili peppers, to figure out how the nervous system responds to and registers changes in body temperature. His team searched for a certain gene that induces this response, finally locating it after scouring millions of DNA fragments. Simultaneously, in 2002, Ardem Patapoutian, a scientist at Scripps Research in La Jolla, California, independently discovered another receptor that responds to low temperatures. The discovery of these receptors cascaded into the identification of numerous other receptors for temperature change.
But Patapoutian’s team investigated beyond just the molecular systems behind temperature response. They worked with the broad field of somatosensation, a component of the body that includes the five senses (sight, smell, taste, touch, hearing) on top of things like pain and body position. This meant that the types of receptors Patapoutian sought changed—temperature was monitored through ion channel receptors, whereas touch was transduced through a mechanical sensor. The difference is that ion channels open when a certain chemical’s binding to the protein induces a change in membrane potential, whereas mechanical channels open in response to physical deformation of the protein.
Thus, eight years later, Patapoutian unveils the genes for a mechanical sensor that communicates touch. Four years following that discovery, the genes he uncovered were found to be crucial in the regulation of other vital bodily functions as well, such as breathing.
Scientists hope that this newfound knowledge will be applied to the development of treatments for disease conditions such as chronic pain.
The Prize, released on October 4, 2021, awards the two scientists evenly 845k euros.
