The Nobel Assembly said Monday that the scientists’ discoveries had unlocked one of the secrets of nature by explaining the molecular basis for sensing heat, cold and mechanical force. It added that the duo’s work had also laid the groundwork for research into treatments for a range of diseases including chronic pain.

Dr. Julius was born in 1955 in New York and is now a professor at the University of California, San Francisco. Dr. Patapoutian was born in 1967 in Beirut. He moved to the U.S. in his youth and is currently a professor at Scripps Research, La Jolla, Calif.

In the late 1990s, Dr. Julius used capsaicin, a compound that causes the burning sensation from chili peppers, to identify a sensor in nerve endings of the skin that responds to heat. In separate research, Dr. Patapoutian later used pressure-sensitive cells to discover new sensors that respond to touch in the skin and internal organs.

Both the scientists’ work involved identifying the specific genes involved in either heat or touch. By figuring out what those genes did in cells, they discovered the molecular basis for the sensations of heat or touch.

Dr. Julius discovered that the gene that allows the body to sense capsaicin instructs nerve cells to make a so-called ion channel that opens up in response to heat, allowing electrically charged particles called ions to flood in and send a pain message to the brain. That receptor was later named TRPV1.

That discovery, published in a 1997 paper, sparked a wave of research by large drug makers hopeful that blocking the TRPV1 receptor could treat chronic pain. That work stalled as researchers struggled to show that their compounds worked, and became concerned that some of the candidate drugs could cause a rise in body temperature.

The work also paved the way for the discovery of other ion channels, some of which are currently under investigation for pain and other diseases, said Martin Gunthorpe, who was involved in TRPV1 research at GlaxoSmithKline PLC, and now runs a consultancy specializing in drugs that target ion channels.

One of those channels was a cold-sensing receptor called TRPM8, which Drs. Julius and Ardem uncovered independently of one another, using menthol.

Dr. Patapoutian’s later work on touch uncovered two ion channels, named Piezo1 and Piezo2, that open up in response to pressure. He later showed that Piezo2 played a key role in how the body senses its position and movement.

“I was shocked and of course I had just woken up so not completely in control,” said Dr. Patapoutian. The Nobel Assembly, based in Stockholm, Sweden, initially couldn’t reach Dr. Patapoutian early Monday because he had switched his phone to “do not disturb” mode overnight. Instead, it reached his 94-year-old father, who went on to call Dr. Patapoutian. “Your contacts can still disturb you,” he said.

While the two scientists’ work has overlapped significantly, they made their discoveries independently of one another. “In the early years there was a healthy competition between us, when we were both working on temperature sensation,” said Dr. Patapoutian. “It’s always good to work and compete with great scientists and David is certainly one of them.”

Dr. Patapoutian said that, in his later work on pressure, a key breakthrough came when his team started studying cells in test tubes rather than in the body. That way, they were able to “switch off” different candidate genes in turn to figure out which ones were responsible for responding to pressure.

He said that work was under way to find molecules that block the Piezo channels as these could form the basis of drugs for different types of pain.

Dr. Julius couldn’t immediately be reached for comment. The Nobel Assembly said it had reached both scientists before the announcement and tweeted a photograph of Dr. Julius celebrating the news alongside his wife.

This story has been published from a wire agency feed without modifications to the text