When the sea anemone split from the lineage leading to humans about 600 million years ago, this ancient marine animal’s immune system also developed its own way of fighting viruses, Israeli researchers found in a groundbreaking study.

In peer-reviewed research, scientists from the Hebrew University of Jerusalem, in collaboration with the University of North Carolina at Charlotte, discovered a brand-new protein that has helped the immune system of Nematostella vectensis, the starlet sea anemone, defend against viral attacks for all these years.

“We found a CARD protein — a structural building block we named CARDIB — that prevents unnecessary immune response by binding to the sensor for viruses,” lead author Ton Sharoni told The Times of Israel.

The discovery upends a long-held scientific assumption that the immune systems of all animals, from anemones to humans, descend from a single ancestral antiviral system and fight viruses in the same way.

“Evolution arrived at different molecular solutions to meet the same biological challenge,” he said.

If the moniker brings to mind famous rapper Cardi B, that’s no coincidence — although the protein is pronounced “cardib.”

“That was simply a fun bonus that made the name a little more memorable,” Sharoni said.

“Gene names are often technical and not always easy to remember,” he said. “In this case, we were able to create an acronym, CARDIB, for CARD Inhibitor Binding Protein, that reflects the protein’s function.”

Insights that could help save coral reefs

Sea anemones, along with corals and jellyfish, are cnidarians, a large group of aquatic invertebrates. Because anemones are closely related to corals, the researchers said these immune system findings could lead to new ways to help stem the threat to coral reefs.

“About 30 percent of life in the sea depends on corals, and when corals die, all the fish and the invertebrates depending on them also die,” Prof. Yehu Moran, who supervised the research, told The Times of Israel.

“Since viruses very likely play a part in........

© The Times of Israel