Three Americans — Jeffrey C. Hall, Michael Rosbash and Michael W. Young — won the 2017 Nobel Prize in physiology or medicine for their work on molecular mechanisms that control circadian systems.
The prize committee said the men elucidated how a life-form's “inner clock” can fluctuate to optimize our behavior and physiology. “Their discoveries explain how plants, animals and humans adapt their biological rhythm so that it is synchronized with the Earth's revolutions.” Working with fruit flies, the scientists isolated a gene that is responsible for a protein that accumulates in the night but is degraded in the day. Misalignments in this clock may play a role in medical conditions and disorders, as well as the temporary disorientation of jet lag that travelers experience when crisscrossing time zones.
“The circadian system has its tentacles around everything,” Rosbash explained in an interview with the Howard Hughes Medical Institute Bulletin in 2014. “It’s ticking away in almost every tissue in the human body.” It's also in plants, including major food crops, the article noted, and appears to be tied to “disease susceptibility, growth rate, and fruit size.”
The scientists’ paradigm-shifting work revolves around three genes dubbed “period,” “timeless” and “doubletime.”
Their early work took place in 1984--33 years ago--when Hall and Rosbash worked together at Brandeis and Young at Rockefeller University to isolate the “period” gene, which controls the circadian rhythm of fruit flies. Hall and Rosbash then showed that the level of the protein encoded by this gene changes in a 24-hour cycle, going up during the day and down at night. They theorized that this protein blocked the activity of the period gene.
But to have this effect, the protein would have to reach the genetic material in the cell nucleus, and no one was able to figure out how it got there until Young, in 1994, discovered a second clock gene, now known as “timeless.” He showed that when the protein encoded by timeless bound to the protein made by the gene period, they were able to enter the cell nucleus. He further identified a third gene, “doubletime,” which appeared to control the frequency of the oscillations over a 24-hour period.
The scientists’ paradigm-shifting work revolves around three genes dubbed “period,” “timeless” and “doubletime.”
Their early work took place in 1984--33 years ago--when Hall and Rosbash worked together at Brandeis and Young at Rockefeller University to isolate the “period” gene, which controls the circadian rhythm of fruit flies. Hall and Rosbash then showed that the level of the protein encoded by this gene changes in a 24-hour cycle, going up during the day and down at night. They theorized that this protein blocked the activity of the period gene.
But to have this effect, the protein would have to reach the genetic material in the cell nucleus, and no one was able to figure out how it got there until Young, in 1994, discovered a second clock gene, now known as “timeless.” He showed that when the protein encoded by timeless bound to the protein made by the gene period, they were able to enter the cell nucleus. He further identified a third gene, “doubletime,” which appeared to control the frequency of the oscillations over a 24-hour period.
The genes are said to have “major impacts to human health that have yet to be fully recognized,” said Duke University’s Xinnian Dong. Alzheimer’s, depression, attention-deficit/hyperactivity disorder (ADHD) are among the many conditions that appear to either cause circadian rhythm problems
Other contenders for this year's award were said to be: Yuan Chang and Patrick Moore of the University of Pittsburgh for their work with human herpesvirus 8 (KSHV/HHV8) which is associated with cancer; Lewis Cantley of Weill Cornell of Medicine for the discovery of a cell signaling pathway and its role in tumor growth; and Karl J. Friston of the University College London for his work on algorithms and techniques for the analysis of brain imaging data.
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