Giant Isopods Survive Five Years Without Food Using Stolen Gene and Enormous Stomach

A study published on August 6 in the journal Cell reveals that deep-sea giant isopods can endure starvation for over five years due to a combination of a massive stomach and a stolen gene. Researchers from the Chinese Academy of Sciences examined two giant isopod species: Bathynomus jamesi, collected nearly 3,000 feet deep in the South China Sea, and B. doederleini, from almost 1,000 feet in the East China Sea. They compared these to the intertidal isopod Cleantiella isopus from Qingdao, China. The deepest-dwelling B. jamesi had a stomach occupying about two-thirds of its body cavity, serving as a storage container for scavenged fish, crabs, and dead organic matter. Both giant species possessed the ND1 gene, but B. jamesi expressed it more, slowing energy production to preserve it during starvation. The gene was acquired from a bacterium over 16 million years ago. Experiments with genetically engineered zebrafish, nematode worms, and human cells showed reduced metabolic rates at cold temperatures; food-deprived zebrafish with ND1 lived 37 percent longer at 64 degrees Fahrenheit. The findings offer new insight into deep-sea gigantism and adaptation. Jianhai Xiang, Jianbo Yuan, Yang Li, and Torben Riehl commented on the significance.