Researchers have identified a novel protein in the starlet sea anemone (Nematostella vectensis) that plays a critical role in its defense against viral infections, operating through a mechanism that appears to be the opposite of human antiviral proteins.<\/p>\n
The protein, named CARDIB (CARD Inhibitor Binding protein), was discovered by scientists at the Hebrew University of Jerusalem and the University of North Carolina at Charlotte. While superficially resembling the human mitochondrial antiviral-signaling protein (MAVS), CARDIB functions in an entirely different manner. In vertebrates like humans, MAVS activates the immune system to fight viruses by producing cytokines and inducing apoptosis (programmed cell death) to eliminate infected cells. CARDIB, however, normally suppresses these antiviral defenses.<\/p>\n
“Rather than activating antiviral defenses, CARDIB normally suppresses them,” explained Yehu Moran, a co-lead author of the study. This finding suggests an ancient and parallel evolutionary track for immune system defenses.<\/p>\n
Through experiments using CRISPR gene-editing tools, researchers created mutant sea anemones unable to produce CARDIB. These modified anemones proved significantly more vulnerable to viral infections compared to their naturally producing counterparts. Conversely, anemones producing CARDIB exhibited a slower but more sustained antiviral response, with less programmed cell death occurring among infected cells.<\/p>\n
“Although CARDIB acts as a brake on the immune system under normal conditions, that brake turns out to be essential for mounting an effective antiviral response,” said Ton Sharoni, the study’s lead author. The findings were published in the journal Nature Ecology & Evolution.<\/p>\n
The sea anemone’s immune system, with its unique CARDIB mechanism, dates back at least 648 million years to the Cryogenian period. The researchers propose that this discovery challenges the long-held notion that all animals inherited largely identical antiviral defense systems from a common ancestor.<\/p>\n
To assess CARDIB’s effectiveness in a natural setting, scientists from UNC Charlotte conducted field tests. They introduced both normal and CARDIB-deficient sea anemones into samples of native estuary water in Georgetown, South Carolina. Within 96 hours, the sea anemones producing CARDIB demonstrated significantly better survival and thriving rates.<\/p>\n
“This demonstrated that the pathway we discovered is not simply a laboratory phenomenon,” Moran stated. “It plays a crucial role in helping these animals cope with the viral challenges they face in nature.”<\/p>\n
The discovery of CARDIB opens avenues for exploring other species that may have independently evolved distinct antiviral molecules. This research could potentially lead to new strategies for medical researchers to combat viral threats and prevent future pandemics.<\/p>\n","protected":false},"excerpt":{"rendered":"
Researchers discovered a novel protein, CARDIB, in the starlet sea anemone that suppresses antiviral defenses, a mechanism essential for combating viral infections.<\/p>\n","protected":false},"author":3,"featured_media":2363,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":[],"categories":[3],"tags":[2213,2467,84,2465,2466],"yoast_head":"\n