The 2017 Nobel Prize in Physiology / Medicine won by American scientist who discovered the genetic mechanism that produces biological clock

ByNational Human Genome Research Institute (NHGRI)

The Nobel Prize for Physiology and Medicine, which was expected to be awarded for three consecutive years by Japanese scientists, was announced and presented to three American scientists who discovered the mechanisms of genes and proteins that are found in the living things It was decided to be done.

The 2017 Nobel Prize in Physiology or Medicine - Press Release
https://www.nobelprize.org/nobel_prizes/medicine/laureates/2017/press.html

The prize was decided by Professor Emeritus Jeffrey Hall of Brandeis University, Professor Michael Rothbash and Professor Michael Young of Rockefeller University. The reason for the award was "discoveries of molecular mechanisms controlling the circadian rhythm" (discovery of a molecular mechanism controlling circadian rhythm), and Mr. 3 examined the genes of Drosophila melanogaster and there was a mechanism to regulate the body clock there I found out that there was a big corner for the subsequent research.

Research on biological clocks provided in living organisms has been conducted for a long time and in the 18th century a French astronomer Jean Jacques Dortus de Melan is using observation of leguminous plants. It is known that this plant exercises leaves at night, but De Mellan discovers that plants are kept in a dark place all day long and that they also move the leaves closing in the same way. In other words, it has been highlighted that this plant is not affected by sunlight, but decides the timing to exercise based on the watch in it.


In this way actual events were confirmed, but that mechanism remained a mystery for a long time. Around 1930, German biochemist Bunning had studied the intrinsic rhythm of Drosophila as well as plants and released the hypothesis that it determines the diurnal rhythm based on the biochemical reaction in the body , The breakthrough in this research was made by the California Institute of TechnologySeymour · VenzerProfessor and geneticist Ronald Konopka were two people. Two people who hypothesized that the circadian rhythm is controlled by genes gave substances that make genetic mutation likely to occur in Drosophila and observed changes in their descendants. Then, it was discovered that there are individuals with 2000 sleep patterns that are clearly different from other individuals among 2000 descendants. As a result of examining the gene, I found that the X chromosome contains genes that act on the circadian rhythm.

In addition to pursuing its contents, three people, Hall, Ross Bash, Young who clarified concrete mechanism, were awarded the 2017 Nobel Prize for Physiology and Medicine. In 1984, the genes that Mr. Hall and Mr. Ross Bash 's research team and Mr. Young' s research team respectively found were termed "PER genes" from the period. In addition, Mr. Young's research team found another gene that is producing a circadian rhythm in 1995 and named "TIM gene" from timeless (irrespective of time).

In his 3 research, it is clarified how these genes produce a circadian rhythm of 24 hours. In Drosophila, the PER protein made by the PER gene and the TIM protein produced by the TIM gene form a complex within the cell and become a transcription factor that regulates the function of the gene. It has been shown that this complex produces a transcription feedback loop in the PER and TIM genes and a circadian rhythm of 24 hours is produced.


In the article of Nikkei Science, a part of the mechanism is explained.

2017 Nobel's Physiology and Medicine Prize: Mr. Rice to Discover Genetic Organisms that Produce a Biological Clock | Nikkei Science
http://www.nikkei-science.com/?p=54610

A specific cycle is shown in the above figure (image is M. W. Young "Genes that move biological clock" from Nikkei Science June 2000 issue).

1. In the morning when light hits Drosophila, the complex of PER and TIM in the cell begins to degrade
2. By noon all complexes will disappear. On the other hand, a complex of CYCLE and another protein called CLOCK activates the per gene and tim gene, actively producing each protein
3. In the evening, the generated PER and TIM combine to form a complex
Four. In the night the complex of PER and TIM moves to the nucleus, inactivating CYCLE and CLOCK, suppressing the per gene and tim genes. Return to 1 again

The result of the research by Mr. Mr. 3 is greatly useful for elucidating the mechanism of the biological clock of a living being, including humans, at the genetic level, and it was awarded this year as a result of being evaluated. The award ceremony will be held in Stockholm, Sweden on December 10, 2017, and a prize of 9 million Swedish kronor (about 125 million yen) will be awarded to Mr. 3.