A team at Brown University found that Opsin3 is a protein closely related to rhodopsin, a protein that enables low-light vision. It regulates the amount of pigment produced in human skin, which is a determining factor in skin color.
When humans spend their time in the sun without proper skin protection, the sun’s ultraviolet (UV) radiation sends a signal to the skin that produces more melanin – which prevents the effects of radiation on cancer, and the skin gets darker. Solar ultraviolet radiation is divided into two parts: short-wave radiation or UVB, and long-wave radiation or UVA.
Compared to many studies that have found that UVB can cause darkening of human skin, scientists are less aware of the skin’s response to UVA which is a richer solar ultraviolet radiation. In 2015, the authors discovered that the first suggestion that melanocytes (special skin cells that produce pigment melanin) are rich in clues to Opsin3, they believe that Opsin3 may be a receptor for detecting UVA and indicates an increase in melanin production.
“We have discovered the role of Opsin3 in human melanocytes and identified molecular steps that allow Opsin3 to perform this function,” Oancea said. “In the process of studying how much pigment Opsin3 regulates cell production, we were surprised to find that it does not depend on light. This mechanism is completely new, and once we understand Opsin3, it may be a good target for the treatment of pigmentation.”
Now that they have determined the role of Opsin3 in skin pigmentation, the team is looking to learn about its birth in other parts of the body and what functions it might have. Olinski is working hard to determine where and how Opsin3 works in the brain, which is the first time it has been discovered.
The finding that Opsin3 regulates the color produced by melanocytes suggests that Opsin3 can be used as a target for the treatment of pigmentation. Hyperpigmentation is characterized by excessive melanin; hyperpigmentation, such as albinism, characterized by too little melanin, which greatly increases the patient’s sensitivity to solar ultraviolet radiation and susceptibility to skin cancer. Currently, most pigmentation disorders have no treatment. Oancea says that before scientists can target Opsin3 in the skin, they need to understand how it works in other parts of the body and how to turn it on or off.