Causes of insomnia due to time zone changes

Circadian watches (clock to beat sleep rhythm) regulates the time of biological functions in most high-end organisms. Anyone who flies through many different time zones has experienced insomnia, which can occur when the time is overturned.

A new study by Cornell and Dartmouth researchers explains that behind the biological structure is how this circadian clock senses light through the process of converting energy from light to reactions. chemistry in cells. The paper is published in Science.

Circadian clocks in the cell respond to the difference of light between day and night, thus allowing this mechanism to anticipate changes in the environment by gradually performing metabolic processes for the cycle. everyday. This watch plays a role in many processes such as: Determining when the plant opens its wings, flowers come out in the morning or closes at night; or decide when mushrooms release spores to reach maximum growth.

In humans, Circadian clocks are responsible for why we fall asleep at night and wake up in the morning, they control many of the main (regular) regulatory functions. The breakdown of sleep rhythms can cause Jet lag, mental illness and even some forms of cancer.

Brian Crane, a former author of the paper and an assistant professor at Cornell University's Department of Chemistry and Biochemistry, said: 'This watch is specially preserved in all organisms, and in particular through organisms. the evolution of hundreds of millions of years. '

The study revealed how mold (Neurospora crassa) uses circadian meter light sensors to control the production of carotenoids, helping to protect against the damage from ultraviolet radiation from the sun shortly after. when the sun rises.

The researchers studied a vivid, protein-based chromophore that attracted photons (light quanta) or light particles (small light particles), and energy taken from light. Bright causes a series of interactions, eventually leading to physical changes on the surface of the protein. The structural changes on the surface of this protein displace a lot of things that affect gene expression, like things like turning off and opening the carotenoid production function.

By replacing a single atom (sulfur substance to get oxygen) on the surface of the colorful protein, the researchers were able to tighten this sequence of events and prevent structural changes on the protein surface. In this way, breaking the principle of carotenoid production.

Brian Zoltowski, lead author of the paper and graduate student at Cornell University's Department of Biology and Chemistry, said: 'Now we can prove that in organisms, the physical changes in this protein are directly involved. Next to its function. '

The circadian clock allows the fungus to regulate and produce carotenoids only when they need to be protected against the sun's rays. The same ' twist ' can also be responsible for regulating the time for a human sleep cycle.

'We were very interested in trying to understand behavior at the molecular level,' Crane said, 'this is a great example of Chemistry - Biology, to a certain extent in this example. We can mess up a single chemical molecule and really change the behavior of a complex mechanism. '

Mold (Neurospora crassa) - (Photo: Nigms.nih.gov)

Danh Phuong