FMBA expert spoke about the importance of the Nobel Prize for receptors
The Nobel Prize in Physiology or Medicine in 2021 was awarded to the American physiologist David Julius from the University of California at San Francisco and the American molecular biologist and neurobiologist Ardem Pataputyan from the Scripps Institute for the discovery of ion channels in cells that respond to temperature and touch. This was reported by representatives of the Nobel Committee. The names of the winners were announced at the Nobel Committee ceremony in Stockholm.
Vsevolod Belousov, Director of the Federal Center for Brain and Neurotechnologies of the Federal Medical and Biological Agency, Doctor of Biological Sciences, Professor of the Russian Academy of Sciences, Vsevolod Belousov, considers the awarding of the prize to Julius and Pataputyan absolutely deserved.
“These are world famous scientists, especially Julius, who not only discovered these ion channels, he is perhaps the most famous person among those who study these channels. He, I think, the Nobel Prize shone in any case. Pataputyan also participated in the study of piezo channels that convert mechanical energy into electrical impulses, ”
The human ability to feel warm, cold and touch has been of interest to researchers for centuries. In the 17th century, the philosopher Rene Descartes suggested that there are certain threads connecting different parts of the skin with the brain – and, for example, if you bring your hand to a fire, a signal of intense heat will be sent to the brain along such a thread. Further observations confirmed that there are specialized sensory neurons that respond to environmental changes.
“However, before the discoveries of Julius and Pataputyan, it was unclear how temperature and mechanical stimuli are converted into electrical impulses in the nervous system,” the Nobel Committee said.
In the second half of the 1990s, Julius used capsaicin, a hot chemical from chili peppers, to find heat receptors.
It was already known that capsaicin activates nerve cells, causing pain. Julius's team has assembled a library of millions of DNA fragments corresponding to genes that are expressed in sensory neurons that respond to pain, heat and touch. By expressing individual genes from this collection in cell cultures, scientists were able to find the very single gene that made cells sensitive to capsaicin.
Experiments have shown that this gene encodes a previously unknown ion channel protein. The new receptor, which is activated at temperatures perceived as painful, the scientists named TRPV1.
Then Julius and Pataputyan, independently of each other, using menthol, discovered the TRPM8 receptor that responds to cold. Scientists also managed to open additional ion channels associated with these receptors and activated when exposed to different temperatures.
Pataputyan was also looking for an answer to the question of how mechanical stimuli are converted into sensations of touch and pressure. His team injected individual cells with a micropipette until they found a line of cells that responded with a measurable electrical signal.
The researchers then identified 72 candidate genes that encode possible cellular receptors. By disabling these genes one by one, the researchers discovered the one responsible for mechanosensitivity in cells. So they discovered the Piezo1 ion channels, which are present in large numbers in sensory neurons, and then Piezo2, which are similar to them. Both channels were activated directly by pressure on the cell membranes.
Subsequent studies have also shown that Piezo1 and Piezo2 regulate many important physiological processes – respiration, blood pressure, bladder function, etc.
The discoveries of Julius and Pataputian made it possible to understand how heat, cold and mechanical influences allow us to perceive the world around us and adapt to it, react to temperature, touch and feel the movement of parts of our own body. They gave rise to many new studies on the role of the discovered receptors in various physiological functions. The knowledge gained is now being used to develop treatments for a wide range of diseases.
According to Belousov, new discoveries in the field of ion channels will help scientists develop new pain relievers.
“All animals and humans have ion channels. TRP channels are responsible for our feeling of warmth, cold, and they are also able to sense other parameters. In addition, they are responsible for pain sensitivity, which means that it is necessary to develop all sorts of analgesics that affect these TRP channels, “- said the scientist.
In addition, these discoveries led to the emergence of a new scientific field – thermogenetics.
“This is what my colleagues and I and several other laboratories in the world are doing. We use these channels to control the activity of different cells, for example, the pancreas. We take these channels and put them in other cells that usually do not have them, we make them sensitive to temperature. Thus, we can control the activity of neurons or the release of insulin using different heating methods – infrared radiation, or focused ultrasound, added Belousov. “These methods can be used for a new therapy for epilepsy, in the creation of well-known brain-computer interfaces.”
The 2020 Nobel Prize in Physiology or Medicine was awarded to American virologists Harvey Alter and Charles Rice and British virologist Michael Houghton for the discovery of the hepatitis C virus.
“For the first time in history, the hepatitis C virus can now be cured. The discoveries of the laureates in the field of medicine have revealed the cause of the remaining cases of chronic hepatitis and made it possible to carry out blood tests and the use of new drugs that have saved millions of lives, ”said representatives of the Nobel Committee.
The discovery of the hepatitis C virus was an important advance in the fight against viral diseases. Thanks to their work, highly sensitive blood tests for hepatitis C virus are now available, which has made it possible to virtually eliminate transfusion-related hepatitis C in many parts of the world. It was also possible to quickly develop antiviral drugs to combat hepatitis C. For the first time, chronic hepatitis became possible to cure, which gave hope for getting rid of it completely in the future. However, this will require the coordinated work of health authorities around the world.
