Without the enzyme that “regenerates” telomeres (the ends of DNA), stem cells lose functionality and the organism rapidly ages, while it acquires cancer resistance. The finding, which has significant implications in cancer and aging research, was presented yesterday at the 2nd IFOM-IEO Campus Meeting on Cancer (May 5th – 8th, IFOM-IEO Campus, Milan, Italy) by Marìa A. Blasco, of the Spanish National Cancer Center (CNIO) in Madrid (Spain).
Our cells’ DNA has a sort of “tail”: the telomeres. Every time our cells divide, telomeres get shorter and shorter. This progressive telomere shortening is compensated by the action of a specific enzyme, called “telomerase”, which is able to regenerate the tails; but in our cells there is not enough telomerase to keep telomeres at a constant length during our lifetime. And when telomeres get too short, cells stop replicating. Scientists have long hypothesized (and partially proved, with several experiments) that telomere shortening is correlated, on the one hand, to the general aging of the body (when many cells in a tissue stop replicating, the tissue becomes unable to regenerate itself and gets “old”) and, on the other hand, to cancer (tumour cells replicate much more than normal cells, therefore they need some mechanism to counteract natural telomere shortening).
To make the picture even more complicated, stem cells (the other big “stars” of modern biology research) might be the only cells that are able to produce the enzyme telomerase. Intuitively this makes sense, since stem cells are the “mother cells” of all cells, and they are necessary to the body to regenerate tissues and organs during lifetime. But, what is the role of telomerase in stem cells? And what could happen if the enzyme is absent? To answer these questions, Blasco and colleagues set up a series of experiments in mice. And they found that the lack of telomerase causes a severe defect in the fundamental functions of stem cells. “In particular – Blasco said – we have been looking at skin stem cells. And we observed that, in genetically modified mice that did not express telomerase, stem cells lost their functionality and became unable to regenerate the damaged epithelial tissue. On the whole, these mice aged more rapidly than normal mice. But, there was a very interesting side effect: without telomerase, mice showed a marked cancer resistance.” Further experiments on telomeres structure showed that every time the shortening process is altered, the result is either “early aging and cancer resistance” (if shortening is boosted), or “aging inhibition and more cancer occurrence” (if shortening is reduced).
Laser activated gold pyramids could deliver drugs, DNA into cells without harm
24.03.2017 | Harvard John A. Paulson School of Engineering and Applied Sciences
What does congenital Zika syndrome look like?
24.03.2017 | University of California - San Diego
Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.
The results will be published on March 22 in the journal „Astronomy & Astrophysics“.
Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...
Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.
Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...
In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...
20.03.2017 | Event News
14.03.2017 | Event News
07.03.2017 | Event News
24.03.2017 | Materials Sciences
24.03.2017 | Physics and Astronomy
24.03.2017 | Physics and Astronomy