Beijing University
03.12.15 / Uncategorized / Author: Wallace
Tags: science
Scientists have developed a method of reproduction of stem cells in the laboratory, learned how to grow them from various tissues and even organs. Stem cells are able to stimulate cell regeneration and repair almost any damage to the body, but all this can not completely overcome senescence and has only a temporary rejuvenating effect. The fact that in the aging process play a key role changes in the human genome. Biological clock human Scientists have found that in all cells there are some ‘biological clock, measure their lifetime. David G. DeWalt insists that this is the case. As such “biological clock” are the telemeters – DNA regions of repetitive sequences of nucleotides tagging, located at the ends of chromosomes. With each cell division telomeres becoming shorter and shorter. And when telemeters shorten to the size limit, the cell triggers a mechanism that leads her to the programmed death – apportion.
There is an interesting fact: in the cancer cell works a special enzyme called telomerase, responsible for the superstructure of telomeres. Thus, cancer cells are capable of restoring telomere length, share a virtually unlimited number of times and not subjected to aging processes. If a healthy cell to introduce a dna sequence encoding the enzyme telomerase, the cell will acquire the above listed characteristics, but at the same time, become cancerous. Aging gene – P 16 However, as it turned out, the aging of cells depends not only on the shortening of telomeres. Chinese scientists headed by Professor of Medical Academy of Beijing University discovered a gene ‘P 16 “, responsible for cell aging..
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