MOLECULAR biologist Elizabeth Blackburn has become the first Australian woman to win a Nobel prize.What she discovered:
Professor Blackburn - whose pioneering work on telomeres, the protective caps on the ends of chromosomes, has opened up new lines of inquiry into growth, ageing and disease - is the 2009 Nobel laureate for physiology or medicine.
"Yes, I've won," said Professor Blackburn, 60, when The Australian contacted her in San Francisco just before the official announcement. "I can't talk now. I've got to speak to somebody in Sweden."
She is only the ninth woman to be awarded the physiology or medicine prize since its inception in 1909, and only the 36th female laureate in any category since 1901, when the first Nobel prizes were awarded in chemistry, physics, medicine and peace.
The Tasmanian-born professor's multi-disciplinary work on telomeres, stress-related disease and meditation has given tantalising evidence of the connection between mind and body.
She will share the 10 million Swedish kronor ($1.6 million) Nobel award with Carol Greider and Jack W. Szostak, the Nobel assembly at the Karolinska Institute in Stockholm announced last night.
A telomere is a region of repetitive DNA at the ends of chromosomes, which protects the end of the chromosome from destruction. Its name is derived from the Greek nouns telos (τἐλος) "end" and merοs (μέρος, root: μερεσ-) "part".He was wrong, but science didn't throw up its collective hands and say "God did it, mow send me your moneies!" Instead bright people kept searching for the answer. Continuing:
A Russian theorist Alexei Olovnikov was the first to recognize (1971) the problem of how chromosomes could replicate right to the tip, as such was impossible with replication in a 3’ to 5’ direction. To solve this and to accommodate Leonard Hayflick’s idea of limited somatic cell division, Olovnikov suggested that DNA sequences would be lost in every replicative phase until they reached a critical level, at which point cell division would stop.
During cell division, the enzymes that duplicate the chromosome and its DNA cannot continue their duplication all the way to the end of the chromosome. If cells divided without telomeres, they would lose the ends of their chromosomes, and the necessary information they contain. (In 1972, James Watson named this phenomenon the "end replication problem".) The telomeres are disposable buffers blocking the ends of the chromosomes and are consumed during cell division and replenished by an enzyme, the telomerase reverse transcriptase.This worked its way into science fiction. I know Heinlein even incorporated this concept into his 1980's Lazarus Long focused work. There may have been others.
Elizabeth Blackburn compared telomeres to the tips on the ends of shoelaces that keep them from fraying.
In 1975-1977, Blackburn, working as a postdoctoral fellow at Yale University with Joseph Gall, discovered the unusual nature of telomeres, with their simple repeated DNA sequences composing chromosome ends. Their work was published in 1978. The telomere shortening mechanism normally limits cells to a fixed number of divisions, and animal studies suggest that this is responsible for aging on the cellular level and sets a limit on lifespans. Telomeres protect a cell's chromosomes from fusing with each other or rearranging—abnormalities which can lead to cancer—and so cells are normally destroyed when their telomeres are consumed. Most cancers are the result of "immortal" cells which have ways of evading this programmed destruction.