Unique genes make water bears tolerate extreme environments

Unique genes make water bears tolerate extreme environments

Its specific protein helps cells resist DNA damage.

The latest genetic research on genome sequencing was published in the British journal Nature Communications on September 20. The study found a gene in the slow-walking animal water bear worm whose protein can resist DNA damage in human cultured cells. This suggests that proteins specific to slow-walking animals will help cells resist DNA damage.

The water bear bug, the most vital creature known on earth, is famous for its ability to survive in a vacuum. The small aquatic animals, known as walking animals, can survive under extreme pressure (including a vacuum) without protective measures, or can successfully recover from freezing for more than 30 years. However, it was not known how it was done before.

The peculiar ability of walking animals has prompted researchers to investigate their genomes. The results of the first genome sequencing showed that during the evolution of slow-walking animals, a large number of genes were obtained from other species through horizontal gene transfer (DNA transfer between genomes of different species). However, the root cause of the ability of walking animals to withstand extreme environmental stress remains a mystery.

Takeshi Takeshi, a researcher at the University of Tokyo in Japan, and colleagues revealed the high-quality genome of water bears known for their tolerance to high-pressure environments. They found no evidence of large-scale horizontal gene transfer, but compared with flies and worms, there are more genes responsible for tolerance to high-pressure environments. In addition, they found a protein that binds to DNA and helps protect cultured human cells from X-ray radiation. By comparing the genes of slow walking animals with those of other species in detail, the authors found that the genes in which the protective protein specifies the genetic code are unique to slow walking animals.

These results do not support the view that tolerance originates from horizontal gene transfer. Although it is not clear how the unique adaptability of walking animals works at the molecular or organic level, the above results suggest that slow walking animals have evolved into a unique "secret" against stress conditions. (reporter Zhang Mengran)