Aaron Ciechanover, 1947–, Israeli biochemist, M.D. Hebrew Univ.–Hadassah Medical School, Jerusalem, 1974; D.Sc. Technion (Israel Institute of Technology), Haifa, 1982. He has been on the faculty at the Technion since 1986. Ciechanover received the 2004 Nobel Prize in Chemistry with Avram Hershko and Irwin Rose for the discovery of the mechanism underlying protein degradation. Their work resulted in a molecular-level understanding of how cells control processes such as DNA repair, cell division, and immune functions by using a regulatory tag called ubiquitin to mark selected proteins for degradation. This knowledge has helped in the fight against diseases—for example, cystic fibrosis and cervical cancer—that result when the degradation is not carried out properly.