Updated

Updated · ScienceDaily · Jun 30

Scientists Find 600-Million-Year-Old Sea Anemone Antiviral System That Reverses Human MAVS Logic

Updated

Updated · ScienceDaily · Jun 30

Scientists Find 600-Million-Year-Old Sea Anemone Antiviral System That Reverses Human MAVS Logic

Q: Why must sea anemones turn off their immune system to fight viruses?

Sea anemones appear to “turn off” part of their immune system because that shutdown is actually required for their antiviral defense to work properly. Researchers found that a sea anemone protein called CARDIB normally suppresses antiviral activity. That seems backward, because in humans a related protein, MAVS, helps switch defenses on. But when scientists used CRISPR to remove CARDIB, the animals did not become better protected. They became much more vulnerable: viruses multiplied faster, and the anemones failed to mount an effective antiviral response. The evidence suggests CARDIB acts less like a weakness than a control system. By keeping antiviral defenses restrained under normal conditions, it may help the animal maintain the right balance and then respond in a coordinated way when viruses strike. Without that “brake,” the system does not function correctly. The result was not limited to the lab. In outdoor marine mesocosms, genetically modified anemones lacking CARDIB accumulated substantially more viruses, showing that this unusual mechanism matters in real-world conditions. The broader significance is that sea anemones and humans solved the same problem—how to survive viral infection—in very different ways. In sea anemones, immune suppression is not the opposite of antiviral defense; it is part of the defense itself. The study shows evolution did not produce one universal immune strategy, but multiple distinct ones.

2 articles · Updated · ScienceDaily · Jun 30

Researchers identified CARDIB, a sea anemone protein that resembles the human antiviral protein MAVS but suppresses immune signaling instead of activating it.
CRISPR tests showed CARDIB is still essential: sea anemones lacking the gene became far more vulnerable to infection, with faster viral growth and weaker antiviral responses.
Outdoor marine mesocosm experiments in South Carolina confirmed the pathway works in nature, where modified anemones accumulated substantially more viruses than unmodified animals within days.
The findings, published in Nature Ecology & Evolution, challenge the idea that animals inherited one core antiviral system and suggest evolution produced multiple distinct defenses against viruses.

Sources

ScienceDaily18h ago

Scientists Discover Unique Antiviral Defense System in Sea Anemones

vietnam.vn9h ago

Discover the completely different antiviral strategy of sea anemones.

Could this ancient sea anemone protein inspire new drugs for human viruses?

Why must sea anemones turn off their immune system to fight viruses?

What other immune secrets are hiding in our oceans?

Discovery of CARDIB in Sea Anemones Unveils a Counterintuitive Antiviral Strategy, Redefining Immune Evolution

Overview

A groundbreaking study published in June 2026 in Nature Ecology & Evolution revealed that sea anemones use a surprising and counterintuitive antiviral defense strategy. Researchers discovered a novel protein called CARDIB, which operates through a unique mechanism that is fundamentally different from how humans fight viruses. Instead of following the well-known human antiviral processes, CARDIB’s approach highlights that evolution can create diverse and unexpected solutions to viral threats. This finding challenges traditional views of immunity and shows that ancient organisms like sea anemones can teach us new ways to understand and potentially improve antiviral defenses.

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