Illustration of the British biochemist Tim Hunt (born 1943). Hunt is best known for his research into the regulation of the cell cycle. Working with Atlantic purple sea urchins (Arbacia punctulata) Hunt discovered cyclin proteins, which play a key role in regulating the cell cycle, the sequence of events that lead to a cell dividing into two daughter cells. Hunt received a share of 2001 Nobel Prize in Physiology or Medicine, along with Paul Nurse and Leland Hartwell, for this work.