How 3D Changes in the Genome Turned Sharks Into Skates | Quanta Magazine

A little skate (Leucoraja erinacea) in the ǧƵ's Marine Resources Center. Credit: Andres Pruna

This article is about a recent study that in with origins in a Whitman Center collaboration between the late José Luis Gómez-Skarmeta, etsuya Nakamura, Neil Shubin, Elisa Calle-Mustienes, and others.

The marine creatures called skates skim along the sea bottom, rippling their winglike pectoral fins to propel themselves and to stir up small creatures hiding in the sand. Their unusual flattened body plan makes them one of the oddest families of fish in the sea, and it seems even odder that they evolved from streamlined, sharklike carnivores that swam about 285 million years ago. 

Now researchers have discovered how skates evolved their distinctive profile: Rearrangements in the skate’s DNA sequence altered the 3D structure of its genome and disrupted ancient connections between key developmental genes and the regulatory sequences that governed them. Those changes in turn redrafted the animal’s body plan. The scientists in Nature in April.