The 2017 Nobel Prize for Medicine has been awarded to three American scientists. Jeffrey Hall, Michael Rosbash and Michael Young were awarded for their discoveries of the molecular mechanisms controlling the circadian rhythm. “Using fruit flies as a model organism, this year's Nobel laureates isolated a gene that controls the normal daily biological rhythm,” the award committee said. “They showed that this gene encodes a protein that accumulates in the cell during the night, and is then degraded during the day.” Circadian rhythms adapt one's physiology to different phases of the day, influencing sleep, behavior, hormone levels, body temperature and metabolism. The prize for physiology or medicine is first Nobel Prize awarded each year. The prizes for physics, chemistry, literature and peace will also be announced from Tuesday to Friday respectively; and the prize for economics on Monday, October 9. The prize comes with $1.1 million. Who are they? Jeffrey C. Hall was born 1945 in New York, USA. He received his doctoral degree in 1971 at the University of Washington in Seattle and was a postdoctoral fellow at the California Institute of Technology in Pasadena from 1971 to 1973. He joined the faculty at Brandeis University in Waltham in 1974. In 2002, he became associated with University of Maine. Michael Rosbash was born in 1944 in Kansas City, USA. He received his doctoral degree in 1970 at the Massachusetts Institute of Technology in Cambridge. During the following three years, he was a postdoctoral fellow at the University of Edinburgh in Scotland. Since 1974, he has been on faculty at Brandeis University in Waltham, USA. Michael W. Young was born in 1949 in Miami, USA. He received his doctoral degree at the University of Texas in Austin in 1975. Between 1975 and 1977, he was a postdoctoral fellow at Stanford University in Palo Alto. From 1978, he has been on faculty at the Rockefeller University in New York.