Hunt, R Timothy (1943– )

British microbiologist who was awarded the Nobel Prize for Physiology or Medicine in 2001, shared with US geneticist Leland H Hartwell and English microbiologist Paul Nurse, for his discovery of the cyclin class of proteins and his subsequent work in determining their role in the regulation of the cell cycle.

In the early 1980s, while studying sea urchins as a model cell system, Hunt discovered a class of proteins known as cyclins. He showed that cyclins were responsible for controlling the function of the important cell cycle regulator cyclin-dependent kinase (CDK). Hunt found that cyclins were formed and degraded at each cell division (with the levels present varying periodically throughout the cell cycle) and that they were conserved during the evolution of an organism.

Hunt's work proved that periodic protein degradation was an important control in the cell cycle. Ten different cyclins have been found in humans, showing that his research can be directly applied to the human cell cycle. This is important to our understanding of the conditions that cause defects to occur in the cell cycle, such as the development of cancer cells, and could lead to new possibilities for cancer treatment.

Hunt received his PhD from the University of Cambridge in 1968. He has held the post of principal scientist at the Clare Hall Laboratories of the Imperial Cancer Research Fund since 1991. Hunt was elected a fellow of the Royal Society in 1991 and became a foreign associate of the US National Academy of Sciences in the same year.