Four AAAS members are among the winners of Nobel Prizes in the sciences this year, including one who published key papers on his prize-winning work in Science.
Thomas Steitz, co-winner of the 2009 Nobel Prize in Chemistry, is a AAAS member and also a past winner of the Newcomb Cleveland Prize from AAAS, awarded each year since 1923 for outstanding articles published in Science.
Science published two papers by Steitz and his team on the structure of a subunit of the ribosome on 11 August 2000. He and his co-authors won the 2000-2001 Newcomb Cleveland Prize for the papers, which were at the heart of the Nobel Prize-winning research.
The three scientists who shared the Nobel Prize for Physiology or Medicine are AAAS members—Elizabeth Blackburn of the University of California, San Francisco; Carol Greider of the Johns Hopkins University School of Medicine; and Jack Szostak of the Massachusetts General Hospital. They were honored for their work on telomeres, the ends of chromosomes, and the enzyme called telomerase that forms them.
Steitz, a professor of molecular biophysics and biochemistry at Yale University, shared the Nobel chemistry prize with Ada E. Yonath of Israel's Weizmann Institute of Science and Venkatraman Ramakrishnan of the Medical Research Council Laboratory of Molecular Biology in Cambridge, England. The three researchers won for studies that revealed the atomic structure of the ribosome, the cell's protein factory.
Steitz told the Reuters news agency by phone from his office in Connecticut that he received a “nice wake-up call” at 5:30 a.m. on 7 October when he was notified of the Nobel. “I'm very excited of course,” he said. “It's so nice to be appreciated.”
Steitz, Yonath and Ramakrishnan used the tools of X-ray crystallography to elucidate the structure and function of the ribosome. Ribosomes “read” the genetic information from DNA, as transcribed in messenger RNA, to make proteins such as oxygen-transporting hemoglobin, the antibodies of the immune system, hormones such as insulin, and the collagen of the skin. Understanding how the ribosome works at the atomic level is crucial to a better understanding of some of the key cellular processes of life.
The ribosome is divided into two main parts, the “large subunit” and the “small subunit.” In his 2000 Science papers, Steitz used high-resolution crystallography to reveal the structure of the large ribosome subunit for the bacterium Haloarcula marismortui.
According to a background document from the Royal Swedish Academy of Sciences, Yonath and Ramakrishnan published similar structural detail on the small ribosomal subunit of the Thermus thermophilus bacterium in independent articles published in other journals in September 2000. Those papers, along with the papers by Steitz and his colleagues, demonstrated that it was possible to map the function of ribosomes at the most basic, atomic level.
Ramakrishnan and his co-workers have published several subsequent papers in Science on aspects of their work, including one published last year. Ramakrishnan has determined the structure of the full bacterial ribosome as well as structures of the ribosome that bind to protein factors required for efficient biosynthesis.
“This year's three Laureates have all generated 3D models that show how different antibiotics bind to the ribosome,” said the Nobel press release on the award. “These models are now used by scientists in order to develop new antibiotics, directly assisting the saving of lives and decreasing humanity's suffering.”
The research that led to the Nobel Prize for physiology or medicine for Blackburn, Greider, and Szostak also has practical implications. The studies “have added a new dimension to our understanding of the cell, shed light on disease mechanisms, and stimulated the development of potential new therapies,” according to the Nobel press release.
Every time a cell replicates, a small segment is lost from the telomere, a finding that has implications for research on aging of cells and for organisms as a whole. And frequently dividing cancer cells often have high telomerase activity, allowing them to maintain the length of their telomeres and remain essentially immortal.
In the 1970s, Blackburn used DNA-sequencing methods to show that telomeres—the caps at the end of chromosomes—are made of short, repeated pieces of DNA. She and Szostak then discovered that a unique DNA sequence in the telomeres protects the chromosomes from degradation.
Blackburn and Greider, who was then Blackburn's graduate student, went looking for the mechanism that forms and maintains telomeres. On Christmas Day 1984, Greider saw the first evidence in the lab that an enzyme, which she and Blackburn named telomerase, was responsible for constructing telomere DNA.
Blackburn told Bloomberg News that the Nobel honor for her and Greider is “a hopeful sign” for women. In the future, people will say, “Oh yes, it's not too unusual to have women getting Nobel prizes,” Blackburn said. “Two got one this year. I hope it becomes very normal.”
Willard S. Boyle and George E. Smith won the Nobel Prize for Physics for their development of the charge-coupled device, or CCD, in the 1960s while they were at Bell Laboratories in Murray Hill, New Jersey. The CCD is the electronic eye at the heart of digital cameras and other imaging devices. Boyle and Smith share the physics prize with Charles K. Kao, a naturalized American who did most of his work in England and Hong Kong. Kao discovered how to transmit light signals over long distances through thin glass fibers, opening the door to the fiber-optic communications networks that now carry voice, video and Internet data around the globe.