Researchers decode aging process and cancer-influencing enzyme
Researchers have now completed research that lasted a total of twenty years, looking for a complex enzyme that could prevent the aging process and the development of cancer. The experts repaired the tips of chromosomes in plants, animals and humans.
Scientists at the University of California, Berkeley have completed a study that looked at the effects of chromosomes on cancer and aging. The doctors published the results of their current study in the English-language journal "Nature".
Doctors decipher architecture of telomerase
Deciphering the architecture of the enzyme called telomerase could lead to the development of new drugs to slow down or block the aging process, or open new treatments for cancer. The results of the study provide a structural framework for a better understanding of mutations in human telomerase disease and are an important step on the way to telomerase-related clinical therapeutics, explains study author Kathleen Collins from the University of California, Berkeley. Telomerase affects microscopic envelopes, called telomeres, that cover the tips of the chromosomes in all cells.
What are telomeres?
In humans, each cell contains 23 pairs of chromosomes, including a pair of sex chromosomes (the X and Y chromosomes), which differ between men and women. Australian-American biologist Elizabeth Blackburn, who received the Nobel Prize in Medicine in 2009 for the discovery of telomeres and their protective function in the 1970s, compared them to the tiny plastic caps that protect shoelaces from fraying.
How do telomeres wear out?
At some point, however, the telomeres disintegrate. Every time a cell divides, the telomeres wear out a little more until the cell stops dividing and dies. This is probably very important for the natural aging process, the doctors say. In 1985, Blackburn discovered telomerase and its remarkable ability to extend a cell's lifespan by rebuilding telomeres with pieces of DNA, so to speak, like retreading a tire. In other words, telomeres could be a key to improving longevity and affecting various diseases, doctors say.
Disadvantages of a lack of telomerase
Inherited genetic mutations that affect telomerase function cause disorders, the researchers said. A lack of the enzyme can accelerate cell death. On the other hand, too much telomerase supports unrestrained cell growth in most human cancers. Previous efforts to develop drugs that control the expression of the enzyme have been hampered by an incomplete understanding of the structure and organization of the telomerase complex, the scientists add.
Cryo-electron microscope deciphered molecular structures
To crack the telomerase code, the researchers used a state-of-the-art cryo-electron microscope (Cryo-EM), which made it possible to see the enzyme in action with unprecedented resolutions of seven or eight angstroms. An angstrom is a unit of measurement of length and one billionth of a meter long. Cryo-EM can decipher the molecular structures of compounds that cannot be crystallized and imaged using X-rays. The developers of the technology received the Nobel Prize in Chemistry in 2017.
Can the aging process be reversed in the future?
A study from 2010 showed that the aging process in mice treated with telomerase could be reversed. And in 2011, scientists found a way to convert age-related cells from people over the age of 90 into rejuvenated stem cells that are indistinguishable from those in embryos. Several critical aging markers in cells have been reset in various laboratory experiments, including the size of telomeres. (as)