Ciechanover, Aaron (1947– )

Israeli scientist. With Hungarian-born Israeli scientist Avram Hershko and US scientist Irwin Rose he shared the Nobel Prize for Chemistry in 2004 for his contributions to the discovery of how cells can regulate protein levels by controlled selection and degradation processes.

Ciechanover won his share of the Nobel Prize for his work in explaining how the human cell selects and removes unwanted or damaged proteins. The human cell contains around 100,000 proteins, each of which carries out a specific task in various forms, such as enzymes. Although much work had been carried out on how the proteins were made, little was known about how they were removed once their usefulness to the cell was complete. Ciechever and the other laureates discovered that a protein known as ubitquitin formed a stable covalent bond with unwanted proteins in the cells, effectively labelling them for a disposal process called protein degradation. Later work showed that several ubiquitin molecules attached to the same protein and delivered it to a structure in the cell called a proteasome, where it was degraded. It subsequently was discovered that errors in the cell degradation process can cause diseases such as cystic fibrosis, cancer, and Alzheimer's disease to occur.

Ciechanover was born in Haifa, Israel. He received his master of science degree from the Hadassah Medical School of the Hebrew University, Jerusalem, and was awarded his MD from the same institution in 1974. In 1981, he was awarded a doctorate in medicine from the Technion, the Israel Institute of Technology, Haifa. He held the position of associate professor at the Technion from 1987 until 1992, when he was appointed to the position of full professor there. As of 2004 he held the positions of distinguished professor at the unit of biochemistry and director of the Rappaport Family Institute for Research in Medical Sciences at the Technion.