Researchers at Duke University have discovered the structure of a protein linked to pain and heat perception that is an important step toward developing new therapies that target pain receptors.
“These receptors are gaining particular attention because they are so critical to how we sense and respond to our environment,” said senior study author Seok-Yong Lee, Ph.D., assistant professor of biochemistry at Duke University School of Medicine.
Their discovery? It is an ion channel in the cell surface membrane called TRPV2, which plays a role in a number of biological processes.
Ion channels are scattered across all cell membranes and act as gatekeepers of information flowing in and out of cells, the researchers said.
In the case of TRPV, this information takes the form of calcium ions that function like turning a valve open and shut. TRPV receptors open in response to heat or other stimuli, allowing an influx of calcium ions that convey a signal through the nervous system to the brain.
Lee believes that deducing the schematics of these valves can give them the blueprint for designing drugs that target ion channels and may lead to new pain management therapies.
“Our results give a hint as to how one receptor works, a necessary component for developing new treatments for a variety of conditions involving sensation,” Lee said.
Researchers compared the structure of TRPV2 to TRPV1, and found it didn’t “fit the mold for either the open or closed confirmation of the closely related protein.” Instead they speculate it exists in an “in-between stage, suggesting a third state where the channel becomes desensitized to repeated stimuli, much like a person might get used to the beeps of a faulty smoke detector.”
Lee believes that better understanding this desensitized state may well lead researchers to an entirely new way to manage chronic pain.
Their discovery is published in the January 2016 issue of Nature Structural Biology and Molecular Biology.