Tardigrades are microscopic animals famed for surviving extreme temperatures, biostasis and roughly 1,000 times the radiation tolerated by humans. A University of Iowa study describes how the tardigrade protein Dsup binds along DNA and partially unwinds it, reducing damage from ionising radiation. Earlier work delivered mRNA encoding Dsup into mice using polymer–lipid nanoparticles, protecting oral and rectal tissues from radiation. Researchers are exploring uses from reducing radiotherapy side effects to protecting crops and astronauts, though clinical translation will require more safety and delivery research.
How a Tardigrade Protein Could Help Protect Humans from Radiation
Tardigrades are microscopic animals famed for surviving extreme temperatures, biostasis and roughly 1,000 times the radiation tolerated by humans. A University of Iowa study describes how the tardigrade protein Dsup binds along DNA and partially unwinds it, reducing damage from ionising radiation. Earlier work delivered mRNA encoding Dsup into mice using polymer–lipid nanoparticles, protecting oral and rectal tissues from radiation. Researchers are exploring uses from reducing radiotherapy side effects to protecting crops and astronauts, though clinical translation will require more safety and delivery research.
23:21, 07.11.2025Science
Tiny Survivors, Big Possibilities
Tardigrades — microscopic animals often called "water bears" because of their chunky, bear-like appearance — are among the planet's hardiest life forms. At no more than about half a millimetre long, they tolerate extreme temperatures, can enter a reversible suspended state called biostasis, and withstand roughly 1,000 times the radiation dose that would harm a human.
The Molecular Shield: Dsup
A recent study from researchers at the University of Iowa characterises one of the tardigrade's best-known molecular defenses: a damage-suppressor protein called Dsup. Authors Tyler Woodward and Todd Washington published their findings in the Journal of Molecular Biology, using techniques such as mass photometry, biolayer interferometry, small-angle X-ray scattering and microfluidic modulation spectroscopy to probe the protein's behaviour.
The team found that Dsup physically associates with DNA and partially unwinds it, a conformation that appears to reduce the molecule's vulnerability to damaging agents like ionising radiation. According to Woodward, Dsup "clings tightly to DNA — not just at one spot on the molecule but along its entirety," and does not adopt a single rigid shape. Instead, it flexes and shifts, described by Woodward as behaving like "a spaghetti noodle in water."
"Dsup doesn’t have a fixed shape. Instead, it behaves more like a spaghetti noodle in water, constantly shifting, bending and adopting many different shapes." — Tyler Woodward
Origins and Prior Work
Dsup was first identified by a Japanese research team in 2016. The gene that encodes Dsup has a sequence unlike any other known in nature and appears to produce a protein unique to tardigrades. That novelty has driven multiple lines of research exploring whether Dsup's protective properties can be repurposed for other organisms.
From Mice to Medicine (and Beyond)
One promising application is protecting healthy human tissue during cancer radiotherapy. Because radiation is central to treating many cancers, a biological agent that shields normal cells could reduce side effects. Earlier in 2024, the University of Iowa reported in Nature Biomedical Engineering that polymer–lipid nanoparticles can deliver messenger RNA (mRNA) instructions to produce Dsup in cells. In mice, nanoparticles targeted at oral and rectal tissues — areas commonly damaged during pelvic radiotherapy — produced sufficient Dsup to reduce radiation-induced cellular damage. Co-author James Byrne called the approach "entirely novel" for protecting healthy tissue.
Researchers are also investigating other applications, including engineering crops with greater radiation tolerance and designing protections for astronauts on long interplanetary voyages; tardigrades are the only known animals that can survive brief exposure to the vacuum of space.
What Comes Next
While these findings are exciting, translating Dsup into safe, effective human therapies requires further work. Key challenges include ensuring targeted delivery, controlling expression levels, avoiding unintended interactions with human DNA repair pathways, and thorough safety testing. Still, tardigrades — which have existed on Earth for roughly 500 million years — offer a compelling biological model for developing new resilience strategies.