The life span of different mammals can be a hundredfold different. What factors influence the lifespan of species?
Although human understanding of the link between decoding genetics and longevity remains to be developed, a series of studies have revealed important clues that the genome affects lifespan.
The Arctic right whale is the longest known mammal, and can live for 200 years. The average life of a mouse is only two to three years. Squirrels usually live for more than a decade. What factors influence the lifespan of species?
Although human understanding of the link between decoding genetics and longevity remains to be developed, more and more research has found gene clues that determine the lifespan of animals. Here are the three longevity genes discovered by the researchers.
CISD2: Anti-aging genes
Using gene knockout (a genetic function technology that enables scientists to inactivate specific genes), the researchers could make the Cisd2 gene in mice missing. Early studies found that Cisd2 exists in human chromosomes in areas that are responsible for differences in life span. Scientists speculate that Cisd2 plays an important role in maintaining normal mitochondrial work, which has a crucial influence on the maintenance of cell growth and division.
As mice age, the expression of the Cisd2 gene gradually decreased. The researchers found that both male and female mice exhibited signs of premature aging in the absence of the Cisd2 gene, such as cell death, degeneration of nerve cells and myocytes. Recent studies have confirmed that mice that do not have the Cisd2 gene have a relatively short lifespan, and the Cisd2 gene may affect the longevity and genetic pathways of other aging signs. Maintaining sustained expression of the Cisd2 gene may extend human life or delay signs of aging.
Sirtuin Gene: Life Extension
Let us come to know the Sirtuin gene family. There are seven members of the Sirtuin gene family and they are used to write proteins in living bodies. These gene expressions have been shown to affect aging problems such as cancer and metabolic disorders. For example, the SIRT6 gene may have potential effects on the life span of animals. As another example, the SIRT1 gene in mammals is equivalent to the genes used in yeast to extend lifespan. Scientists are looking for evidence that SIRT1 can also affect the life span of mammals.
In terms of life expectancy, SIRT6’s findings are more powerful than SIRT1. In mice lacking SIRT6, both the rate of senescence and the rate of cell degeneration are relatively fast, indicating that SIRT6 may be a key factor affecting DNA self-repair. Having more SIRT6 gene expression can prolong the lifespan of male mice, but has no effect on female mice. Scientists are still exploring the link between the SIRT6 gene and aging and the reasons why SIRT6 acts differently on male and female mice. Once the influence of the Sirtuin gene family is clearly studied, it may contribute to the development of innovative drugs that can prevent geriatric diseases.
Klotho Gene: Cancer Counter
do you know? The ancient Greeks believed that the life of a mortal was determined by the three goddesses, who were able to weave, measure, and cut the “lifeline.” The goddess who can weave or create the “lifeline” is called Klotho. The Klotho gene is named after this goddess because it also has the effect of delaying aging.
At the age of 40, the body’s Klotho level will naturally decline. The Klotho gene regulates a protein called Wnt5a, which promotes the speed of cancer cells and makes the body resistant. Older melanoma patients are more likely to develop resistance to targeted therapies, and the genetic roots are there.
Recently, scientists have discovered that a drug for treating diabetes can send instructions to the body to increase the expression of Klotho. This mechanism will reduce the protein content of Wnt5a, which will weaken the body’s anti-tumor treatment response. When combined with targeted therapies, this drug is expected to delay tumor growth. This discovery provides scientists with ways to fight drug resistance. This finding also applies to the treatment of other cancers affected by the Klotho gene.
Research on the CISD2, Sirtuin and Klotho genes continues. Although there are many puzzles that need to be deciphered, recent research results are gradually helping scientists better understand the role of genes in determining animal life.