If you have struggled to understand why bleak, sunless winter days leave you feeling SAD (read, you are afflicted with Seasonal Affective Disorder), thank this year’s medicine/physiology Nobel winners since their research gives you most of the answers.
If you have struggled to understand why bleak, sunless winter days leave you feeling SAD (read, you are afflicted with Seasonal Affective Disorder), thank this year’s medicine/physiology Nobel winners since their research gives you most of the answers. Three American geneticists, Jeffrey Hall (retired) and Michael Rosbash of Brandeis University and Michael Young of Rockefeller University, have just received the Nobel for their work on the genetic/molecular mechanism that directs the circadian rhythm (biological clock/sleep-wake cycle) in living things. The circadian rhythm is the most telling yet little explored element of evolution—why do living things exhibit behaviour attuned to the rotation of the Earth around its axis and, ultimately, its circumambulation of the Sun? Circadian dysfunction has been linked to many disorders and diseases, and understanding how the biological clock is regulated brings research closer to cures for these.
Beginning in the 1980s—Hall & Rosbash led one team of researchers while Young led another—the researchers isolated and described a gene in fruit flies, dubbed the “period gene”, that encodes a protein (named PER) that builds up in the cell each night and undergoes lysis the following day. Subsequently, they deciphered the molecular regulation of the period gene and PER, and identified the other links in the circadian clock. Their work is rooted in the genetic screens done by molecular biologist Seymour Benzer and geneticist Ronald Konopka, who had together isolated fruit-fly mutants with abnormal hatching rhythms. Other researchers used Hall-Rosbash-Young’s findings to describe how the accumulation of PER serves as a signal to repress expression of the period gene. Joseph Takahashi of the University of Texas Southwestern Medical Centre, among others, studied mammalian circadian rhythms to show how the system is conserved across species. Travel, work and even leisure/recreation have chronic disruptive influences on the body and mind. In the light of the impact Hall, Rosbash and Young have had on chronobiology, the Nobel committee honouring their research is a well-deserved accolade.