Prof. Aaron Ciechanover belongs to a small elite group of Israeli scientists whose studies have gained the widest possible international recognition. The discovery of the Ubiquitin system, which is responsible for the degradation of proteins in the cell, won him the Nobel Prize for Chemistry along with Prof. Avraham Hershko and Prof. Irwin Rose. The system is responsible for maintaining quality control in the cell by disposing of damaged proteins. Aberrations in the system where these proteins are accumulated and not disposed, have been implicated in the etiology of numerous diseases, certain malignancies and neurodegenerative disorders, such as Parkinson’s and Alzheimer’s diseases. The joint study of the three scientists is expected to have far-reaching consequences on the quality of human life and the capacity to save lives by developing drugs to treat aberrations in the system. One drug against cancer is already in wide use.
Aaron Ciechanover was born in Haifa in 1947. After completing high school he studied medicine at the Hebrew University of Jerusalem. In 1973 he received his MD, joined the IDF, and served in the Medical Corps. After completing his military service, he continued his scientific career, joining the laboratory of Prof. Hershko at the Technion’s Faculty of Medicine. Over a period of five years (1976-1981), the two scientists discovered the Ubiquitin system. In 1981, after receiving his doctorate of science, Ciechanover began post-doctoral training at the Massachusetts Institute of Technology (M.I.T.), where he made further breakthroughs in the study of this system. Three years later he returned to Israel, establishing his research laboratory at the Technion, where he was appointed a Distinguished Research Professor in 2002.
Unlike many scientists at that time who studied the mechanisms of the generation of proteins in cells, Ciechanover and his colleagues chose to tackle the issue from the opposite direction, examining the system responsible for their removal. The cells of living organisms are in a constant process of destruction and reconstruction, where damaged and unwanted proteins are removed and replaced by new ones. This process must be controlled, and, accordingly, it is mediated through a molecule – Ubiquitin – that serves as a “death tag.” Ubiquitin molecules attach themselves to proteins that are no longer useful, telling the cell that they are to be destroyed. The marked proteins are transferred to the cell’s “Recycle Bin” where they are broken down and components are reused, if possible.