Molecular basis of radiation resistance in tardigrades and the medical implications.

Abstract

Tardigrades exhibit remarkable resistance to ionizing and ultraviolet radiation, tolerating exposures far beyond the lethal limits for most organisms. Among the tardigrade-derived molecules implicated in this resilience, damage suppressor (Dsup) is the most well-characterized and demonstrates clear radioprotective activity. This mini-review summarizes the molecular mechanisms underlying tardigrade radiation resistance and discusses their potential medical applications. Dsup associates with chromatin, reducing hydroxyl-radical-induced DNA strand breaks and limiting ultraviolet-mediated pyrimidine dimer formation. Human cells expressing Dsup exhibit decreased DNA damage by approximately 40% and enhanced survival following irradiation, indicating that essential protective mechanisms of tardigrades can be functional in mammalian systems. These findings support the exploration of Dsup-based strategies to mitigate radiation-induced cellular injury, improve preservation of biological materials, and enhance resilience in high-radiation environments such as radiotherapy or space missions. Further mechanistic studies of Dsup, DNA repair pathways, and antioxidative systems, along with in vivo evaluations, are essential to fully elucidate the molecular basis of tardigrade radiation resistance. Collectively, these mechanisms provide valuable insights that may guide the development of novel approaches for medical radioprotection.