If The Organism Out of Steam
October 8th 2009 -
This year’s Nobel Prize for medicine has contributed to an ancient mystery of mankind to solve: Why do we age?
The uniform life in Tasmania is probably best suited to devote her devotion to her interests. Elizabeth Blackburn, who was born in 1948 on the island south of Australia, was an early fascinated by all living things. As a child she watched animals and plants. Sometimes she sang the animals before even slightly, closing at their performances and stinging jellyfish and other species with one. Only logical that Blackburn later studied biology, first in Melbourne, then at the British elite University of Cambridge.
The affection of the scientist to supposedly inferior creatures is now half a century been rewarded for their expeditions to Tasmania, with the highest honor that is awarded to scientists. Blackburn, which has, since 2003, an American citizen, will receive this year with the U.S. researchers Carol Greider and Jack Szostak equally amongst the Nobel Prize for Medicine.
In their research they conducted at Yale University and the California-Berkeley, kept Blackburn in their preference for micro-life care. As in higher organisms whose genes do not float on the genetic molecule DNA around freely in the body cells. Rather, they are tangled in a small space packed into chromosomes. In unicellular ciliates of the genus Tetrahymena Blackburn discovered with their PhD student Carol Greider, of which the ends of chromosomes consist of – the so-called telomeres.
Blackburn, Greider, and Szostak have solved a mystery in the 1980s, molecular biologists had been employed for decades: Why can cells divide again and again and thus enable growth? More than 50 years, researchers discovered the mechanism of cell division and were fascinated by the finely tuned interplay of molecules. Only one detail bothered scientists: fact, would disappear with each sharing a piece of genetic material. Of the many proteins that are reproduced to work on cell division, none of the rear building blocks of DNA on a chromosome. They were lost, but the cell would die quickly, because it lacks vital genetic information.
The unicellular Tetrahymena, which looks like a paramecium, helped clear up the apparent paradox. Blackburn looked at the ends of chromosomes, the bases, so those building blocks that make up the DNA composed. On the chromosome of unicellular life, she found a unique sequence of bases. Strange thing was that the DNA appeared to stutter at the ends of quasi. In the same old pattern repeated itself there are two of the four bases. Genetic information as in the rest of the chromosome, for example, about the size or the metabolism of unicellular life, were not stored on these DNA fragments.
Blackburn acknowledged that the repetitions in the DNA is not a freak of nature had sprung, but protected the cells from the quick death. Even 40 years ago had the Nobel laureate Barbara McClintock and Hermann Muller suspects that the ends of chromosomes, protecting the rest of the DNA. How herauszögerten the Zellkappen the Chromosomentod, Blackburn wanted to explore at their unicellular further. However, this was only with the help of other researchers.
Academic conferences often resemble a poker game: How much of your own work you can disclose, without the colleagues – and competitors betrayed – results that he later spends even as his own? On the other advice can help other researchers to obtain the crucial idea for an experiment. Perhaps Blackburn had never received the Nobel Prize had she not told in 1980 of a conference of their stuttering DNA. In the audience sat the geneticist Jack Szostak, who had traveled to a number of experiments depressing to the presentations.
Szostak was born in London but grew up in Canada. He also now has U.S. citizenship – the 56-year-old geneticist since 1979, teaches at Harvard. He had asked at an early age how life began on Earth and why it could create out of a few chemicals, the first organisms swimming about. Szostak was also briefly in his laboratory previously artificially produced in yeast cells and DNA – a molecular biologist frequently used model organism – smuggled. Then each time the disappointment: The chromosomes were cobbled together after a few cell divisions, only fragments of came, the cells died.
Tags: Carol Greider, DNA, Elizabeth Blackburn, Jack Szostak, nobel prize for medicine, Tetrahymena
