Nov 2, 2017: Three scientists connected to lighting—Jeffrey C. Hall, Michael Rosbash, and Michael W. Young—have won a Nobel Prize—the second time in three years. The three biologists won the Nobel Prize in Physiology or Medicine for helping to explain how the human circadian cycle works, and how light affects our daily rhythms.
However, light was not the focal point of their research in contrast to the lighting centric work of Shuji Nakamura, Isamu Akasaki, and Hiroshi Amano, who won the 2014 Nobel Prize in Physics for their invention of the blue LED.
Hall, Rosbash, and Young have revealed the complicated cell-level mechanisms that make the circadian clock tick. For years they have tried on fruit flies that have explained that circadian processes in humans as well. While Hall is affiliated with Rockefeller University in New York, Rosbash and Young are with Brandeis University in Boston.
The circadian clock keeps many biological functions in sync. Artificial light like LED can disrupt the timekeeping, which can have negative impact on health.
These three researcher have identified three genes, including a period gene that assist in making a protein called PER, which settles in a cell’s nucleus. The protien PER tends to blocks the period gene from making more PER, and eventually degrades during the day. A gene called timeless helps to build a protein called TIM that moves PER from one part of the cell into the nucleus. A third gene called doubletime helps build a protein called DBT that delays PER’s accumulation.
All these genes keep the circadian clock in sync, which is important as it regulates important functions like our behavior, hormone levels, sleep, body temperature, blood pressure, and metabolism. If this clock is disrupted, it can impact our health, and can also lead to cancer, diabetes, etc, as studies have proved.
Light has the capacity to throw the clock out of rhythm. “The paradigm-shifting discoveries by the Laureates established key mechanistic principles for the biological clock,” the Nobel Foundation said while announcing the prize. “During the following years, other molecular components of the clockwork mechanism were elucidated, explaining its stability and function. For example, this year’s Laureates identified additional proteins required for the activation of the period gene, as well as for the mechanism by which light can synchronize the clock.”
Professor of neuroscience Carlos Ibañez from the Nobel Assembly stated that “the building blocks of a circadian system consist of a self-sustained 24-hour rhythm generator or oscillator, setting or entraining mechanisms that link the internal oscillator to external stimuli (referred to as zeitgebers, i.e., timekeepers), such as light, and output mechanisms to allow the timely scheduling of physiological processes.”
Ibañez added that “The discovery of self-sustained transcription/translation feedback loops as the central component of the molecular mechanism by which clock genes control circadian oscillations in cells and tissues has led to a new paradigm in our understanding of how organisms anticipate and adapt to the regular daily environmental cues such as light. Since the seminal discoveries by the three Laureates, elucidating a fundamental physiological mechanism, circadian biology has developed into a vast and highly dynamic research field, with important implications for our health and wellbeing.”