Back in August, Dario wrote about how basic science contributes to medical advances and today the Nobel Assembly chose to recognize the importance of such work by awarding the The Nobel Prize in Physiology or Medicine 2009 to Dr. Elizabeth H. Blackburn, Professor Carol W. Greider and Professor Jack W. Szostak for their discovery of “how chromosomes are protected by telomeres and the enzyme telomerase”.
The discovery was made when Dr. Blackburn was sequencing the DNA of the tiny unicellular fresh water animal Tetrahymena, a popular model organism among scientists studying the process of cell division and the architecture of the organelles within the cell, and found repetitive CCCCAA sequences at the ends of their chromosomes. She then teamed up with Prof. Szostak who was then studying the stability of DNA molecules called minichromosomes in yeast, and as the Nobel Prize press release tells us they performed…
… an experiment that would cross the boundaries between very distant species . From the DNA of Tetrahymena, Blackburn isolated the CCCCAA sequence. Szostak coupled it to the minichromosomes and put them back into yeast cells. The results, which were published in 1982, were striking – the telomere DNA sequence protected the minichromosomes from degradation.
Professor Greider, then a graduate student working in Dr. Blackburn’s lab, then identified telomerase, the enzyme responsible for making and maintaining the telomeres. This was a very significant discovery as it proved that telomeres were made using a different mechanism than that used to make the rest of the DNA sequence in a chromosome. Further research by Blackburn, Greider and Szostak and others demonstrated that telomeres are present in a wide range of plants and animals, organisms that diverged from a common ancestor over a billion years ago, and discovered that they play an important role in cellular ageing, first in yeast and subsequently in humans. Telomeres also appear to have a role in cancer, as it appears that in some (but not all) cancers elevated levels of telomerase activity contribute to the cancer cells continuing to divide and produce new cancer cells long after healthy cells would have lost the ability to divide due to the loss of their telomeres, consequently the field of telomerase inhibitors has seen intense activity as scientists seek new cancer treatments. Many of the recent insights into the role of telomeres and telomerase in ageing, inherited diseases and cancer have come from research on mice, particularly genetically modified mice with altered telomerase activity levels, and Professor Greider in particular has been at the forefront of this work for over a decade (1).
We offer our congratulations to this years’ Nobel Laureates in Physiology or Medicine, their work is a striking example of how basic, curiosity-driven research on species that may appear only distantly related to us can illuminate human biology and open up whole new fields of medical research.
It did not escape our notice that the same trio who won this years’ Nobel Prize were awarded the Albert Lasker Basic Medical Research Award in 2006, for the same work. We were delighted to learn a couple of weeks ago that this years Albert Lasker Basic Medical Research Award has been awarded to Professor John Gurdon and Professor Shinya Yamanaka “For discoveries concerning nuclear reprogramming“. The Lasker Foundation has published an excellent summary of their contributions to this exciting field which demonstrates the absolutely crucial contribution of animal research to their work.
A couple of years ago I discussed Professor Yamanaka’s work on the Pro-Test blog, and since then I have had the opportunity to discuss cellular reprogramming on Speaking of Research, which makes it all the more gratifying to see his work recognized in this way so soon.
We offer both Professor Gurdon and Professor Yamanaka our heartiest congratulations, the smart money has to be on them being summoned to Stockholm in the not too distant future.
1) Blackburn E.H., Greider C.W., and Szostak J.W.”Telomeres and telomerase: the path from maize, Tetrahymena and yeast to human cancer and aging.” Nat Med. Volume 12(10), Pages1133-1138 (2006) http://dx.doi.org/10.1038/nm1006-1133