The findings challenge assumptions about the evolution of immunity and suggest that fundamentally different antiviral strategies have emerged across the animal kingdom.

A new study led by Ph.D. candidate Ton Sharoni and Prof. Yehu Moran of the Hebrew University of Jerusalem, in collaboration with researchers from the University of North Carolina at Charlotte, has uncovered a previously unknown antiviral defense mechanism in sea anemones.

Published in Nature Ecology & Evolution, the findings challenge long-held assumptions about the evolution of immune systems and reveal that animals may have developed more than one molecular solution for combating viral infections.

Viruses are among the most persistent threats faced by living organisms. In humans and other vertebrates, antiviral defenses rely on a protein called MAVS, which activates immune responses when viral invaders are detected. Scientists have long sought to understand how deeply rooted this system is in animal evolution.

An ancient model for immunity

To investigate, the researchers turned to sea anemones, ancient marine animals that diverged from the lineage leading to humans more than 600 million years ago. As close relatives of corals and jellyfish, sea anemones offer a unique window into the early evolution of immunity.