An Israeli study has investigated the mechanism by which the skin darkens and the central role of a protein called Atm, which “disables” the production of pigment to prevent mutations from developing
Why the tan does it appear several hours after sun exposure? The mechanism has been explained by some scientists at Tel Aviv University who have published the results of their work on
Journal of Investigative Dermatology
. Well, first a skin repair mechanism from the damage of ultraviolet rays is activated (it is known that exposure to the sun without protection can lead to the development of skin tumors) and only later does it appear pigmentation due to melaninwhich is actually a sort of “shield” against any future radiation.
Repair mechanism
When we are exposed to ultraviolet rays, the first mechanism blocks the second until the DNA correction reaches its maximum and this happens a few hours after exposure to sunlight. «Genetic information must be protected from mutationsso this repair mechanism takes precedence within the cell during exposure to ultraviolet radiation,” points out the study’s first author, Carmit Levi —. The DNA repair mechanism essentially tells all other cellular processes”stop everything and let me work in peace”».
Atm protein kinase
During the experiment, conducted on human and animal skin samples, researchers from Tel Aviv University (in collaboration with Wolfson Medical Center, Weizmann Institute of Science, University of California and Paris-Saclay University) discovered that the DNA repair induced by ultraviolet B rays, driven by a protein kinase called Atmsuppresses the activity of the Mitf gene (melanocyte-inducing transcription factor), thus inhibiting the production of pigment. Conversely, inhibition of Atm in mouse or human skin, either genetically or chemically, induces the appearance of pigmentation.
Prevention of skin cancers
«In previous research we have shown that the protein called Mitf, activated during exposure to UV rays, is responsible for regulating these two mechanisms Levy points out. In the present study we show that another protein, called Atm, which plays a key role in DNA repair, activates one mechanism by disabling the other. This process probably exploits the pigmentation mechanism to maximize the chances that the cell survives without mutations after exposure to radiation. The molecular mechanism under study will be useful as a basis for further research that could lead to new cures against radiation damage; in the long term, it could also contribute to the prevention of skin cancers.
August 13, 2023 (change August 13, 2023 | 16:24)
© REPRODUCTION RESERVED
#Tan #appears #hours #exposure #sun