Kirstin R.W. Matthews, Ph.D.
Fellow in Science and Technology Policy
The announcements of this year’s Nobel Prize winners started on Monday with the award in the fields of physiology or medicine. David Julius (University of California, San Francisco) and Ardem Patapoutian (Scripps Research Institute) were recognized “for their discoveries of receptors for temperature and touch.” Previous research had uncovered how different types of nerve cells react to external stimuli, resulting in the 1944 Nobel Prize in Physiology or Medicine. Building on this knowledge, Julius and Patapoutian followed their curiosity to understand what proteins were involved in telling our nerve cells about environmental stimuli, including touch, heat and cold.
David Julius’ research sought to understand how the chemical capsaicin (found in hot chili peppers) causes a burning sensation. His research group discovered TRPV1, an ion channel, which is a protein that transverses cell membranes and regulates ions that flow from outside to inside the cell. The TRPV1 channel is normally closed, but opens when exposed to high temperatures, capsaicin or similar chemical components. When opened, positively charged ions flow into the nerve cell and as a result, we feel pain.
Following on Julius’ work, Ardem Patapoutian set out to determine if TRP (the class of channels TRPV1 is part of) is temperature-sensitive. In 2002, both Julius and Patapoutian published findings that another protein ion channel, TRPM8, sensed both cold and menthol. Patapoutian’s lab found additional protein ion channels, called Piezo channels, that respond to mechanical pressure. When the cell is exposed to a mechanical force, the ion channel opens, sending a signal to the nerve.
While this research was a major breakthrough in physiology, it can also be viewed as research based on human curiosity. Fundamental research, which led to these discoveries, is often guided by the researchers’ observations and questions about their environment. One could see Julius, for example, looking at a habanero pepper, wondering how something so seemingly benign could cause such a reaction in the body, and seeking out ways to uncover how capsaicin interacts with our nerve cells. Or perhaps Patapoutian was curious how we respond to touch. By pursuing research to satisfy their curiosity, Julius and Patapoutian expanded our understanding of how nerve cells interact with our environment and environmental stimuli. But their work would not have been possible without vital U.S. federal funding and support of basic science, which both scientists received during their careers. The U.S. must continue to prioritize federally funded research to make possible the major breakthroughs and advancements that keep America competitive as a nation.