Nobel Chemistry laureate Irwin Rose talks to the media during the press conference at the Nobel Institute in Stockholm, Sweden, December 7, 2004. [Photo/IC]

DEERFIELD - Irwin Rose, a biochemist who shared the 2004 Nobel Prize in chemistry for discovering a way that cells destroy unwanted proteins - the basis for developing new therapies for diseases such as cervical cancer and cystic fibrosis - has died. He was 88.

Rose died in his sleep early Tuesday in Deerfield, Massachusetts, said spokeswoman Janet Wilson of the University of California, Irvine, where Rose had been a researcher.

Rose had a "formidable intellect and unwavering curiosity about fundamental biological and chemical processes that are the foundation for life," UCI Chancellor Howard Gillman said in a university statement.

Each human cell contains about 100,000 different proteins, which carry out jobs such as speeding up chemical reactions and acting as signals.

Rose, along with Israelis Aaron Ciechanover and Avram Hershko, won the Nobel for discovering how plant and animal cells marked old and damaged proteins with a "kiss of death" molecule - the polypeptide ubiquitin. The proteins are then chopped to pieces.

The process governs such key processes as cell division, DNA repair and quality control of newly produced proteins, as well as important parts of the body's immune defenses against disease, the Royal Swedish Academy of Sciences said in its Nobel citation.

Scientists have been trying to use the process to create medicines, either to prevent the breakdown of proteins or make the cell destroy disease-causing ones. One example is the cancer drug Velcade, which interferes with the cell's protein-chopping machine.