FLICKR, PAUL ASMAN AND JILL LENOBLE
A major pathway for strategically inducing cell death has been shared between humans and coral since their ancestral lineages diverged, according to a paper published today (June 9) in PNAS. The pathway, mediated by cytokines and tumor necrosis factor (TNF) receptors, was once thought to have originated more recently, prior to the divergence of vertebrates and invertebrates, and to have diversified in the vertebrate lineage. But as it turns out, corals have as diverse a collection of TNF proteins as do humans, and TNF-induced apoptosis is involved in coral bleaching.
“The dogma has been if there’s something not in a fly or a worm, something even more ancient such as a coral should be even simpler,” said Steven Quistad, a marine biologist at San Diego ...
