The water bear Hypsibius henanensis possesses special genes that enable it to withstand gamma radiation levels of up to 3,000 – 5,000 gray.
When researchers from various institutions across China closely examined the gene system of the newly discovered water bear species Hypsibius henanensis found six years ago, they identified 14,701 protein-coding genes, of which 4,436 genes (30.2%) are unique to water bears. They also exposed this tiny creature to radiation streams to monitor how gene expression and protein production would be affected, along with the superpowers that these genes confer on the water bear, as reported by Science Alert on November 5.
The water bear is only one millimeter long but possesses many superpowers that make it the most resilient species on Earth. (Photo: iStock).
“Research on several species of water bears has shown that they are the best radiation-resistant animals on Earth“, the research team shared in a paper published in the journal Science. “They exhibit the ability to withstand gamma radiation levels from 3,000 to 5,000 gray (Gy), which is about 1,000 times higher than lethal levels.”
The researchers made three key observations.
- First, a gene called DODA1, which can be transferred from bacteria, produces the pigment betalain that helps neutralize harmful molecules generated by radiation.
- Second, DNA is repaired much faster than usual thanks to a protein unique to water bears called TRID1.
- Third is the increased production of two other proteins, BCS1 and NDUFB8 (which help provide energy).
A thorough analysis of H. henanensis provides more details revealing how water bears manage to live so long. Together, these three factors help protect water bears from the harmful effects of radiation. The next step is to investigate how these protective measures occur in all species of water bears.
Researchers know of 1,500 species of water bears. Water bears are believed to have first appeared before the Cambrian period, around 541 million years ago. Their ability to survive the harshest conditions continues to redefine human understanding of the limits for life on Earth. The radiation-resistant genes of water bears have enormous potential applications in health, space exploration, agriculture, and medicine. By studying how water bears protect themselves from radiation, scientists can develop new materials and technologies that help astronauts avoid the harmful effects of space radiation on the Moon.
The Moon lacks an atmosphere to protect against harmful radiation from the Sun, especially during solar flares. It is also bombarded by cosmic rays, high-energy particles from distant galaxies. Without a protective layer, these particles can penetrate the human body and cause cellular damage. Water bears may pave the way for many beneficial biotechnological advancements for astronauts, such as developing drugs to cope with the effects of space radiation or gene-editing techniques to enhance human endurance.
