The human Longevity Gene
Geneticists have found out why people live longer than flies and monkeys
Humans live significantly longer than insects and even animals of similar size and mass due to the special arrangement of genes associated with the suppression of cellular stress, according to an article published in the journal Nature Communications (Carroll et al., Oxidation of SQSTM1/p62 mediates the link between redox state and protein homeostasis).
"When we inserted the human p62 gene responsible for the stress response into the DNA of flies, such insects lived longer than their relatives under high oxidative stress. This suggests that the ability to respond to cellular stress could give people their relatively long life," says Viktor Korolchuk from Newcastle University (in a press release, How did we evolve to live longer? – VM).
It is believed that the life expectancy of mammals is interrelated with their typical body weight. So, small rodents live relatively short, while whales, elephants and large cats live for tens or even hundreds of years. Sometimes this pattern is violated, as exemplified by the 30-gram Cape diggers and Brandt's moths, whose mass does not exceed 8 grams, living for about 30-40 years.
Another big exception in this regard, as Korolchuk says, is man – on average, people live 1.5-2 times longer than chimpanzees and other monkeys, as well as predators with comparable body weight and size. Scientists have been trying for a long time to understand what made our ancestors live longer, and how various age-related health problems, such as cancer and Alzheimer's disease, can be associated with this.
British molecular biologists and their colleagues from Europe have found a possible explanation for this unusual human quality by studying various genes associated with the so–called autophagy - the process of "processing" unnecessary and damaged cell proteins inside lysosomes, a kind of intracellular "bioreactors".
Autophagy, as scientists believe today, plays an important role in protecting cells from stress. By this word, biologists do not understand psychological stress, but the accumulation of oxidants and various aggressive molecules in the body that damage proteins, DNA and other important components of cells. Such destruction can end fatally for them, and therefore cells constantly produce a whole set of antioxidants that neutralize oxidants, and preventatively destroy already damaged "molecules of life".
The attention of scientists was attracted by the p62 gene, one of the "conductors" of autophagy, whose damage leads to the development of amyotrophic lateral sclerosis, "Stephen Hawking disease", in which a person is completely paralyzed due to mass death of brain cells.
Such a connection prompted Korolchuk and his colleagues to the idea that p62 may play an important role in the survival of brain cells, most of which are not renewed and live with a person all his life. Scientists have tried to uncover the role of this gene and protein by transplanting it into the DNA of flies and tracing how the work of their cells changed after such an "operation".
As this experiment has shown, p62 plays a dual role in the work of brain cells – it is both an "oxygen sensor" and a kind of "trigger" that triggers the process of "garbage collection" and its disposal inside lysosomes. The human version of this protein reacts much more strongly and more accurately to increases and decreases in the concentration of aggressive molecules inside neurons, which significantly prolongs their life in an unfavorable environment.
Korolchuk and his colleagues believe that such improvements in the work of cell purification systems from oxidants and the consequences of their interaction with the "molecules of life" gradually accumulated in the DNA of human ancestors, which allowed them to gradually reach the level of longevity that is characteristic of our species today, and is absent in monkeys and other mammals.
Portal "Eternal youth" http://vechnayamolodost.ru