Andrew Gillis, incoming associate scientist and a Whitman Center Scientist from the University of Cambridge, U.K., was a co-author on this recent study in the Proceedings of the National Academy of Sciences.
By Cristy Lytal
The emergence of jaws in primitive fish allowed vertebrates to become top predators. What is less appreciated is another evolutionary innovation that may have been just as important for the success of early vertebrates: the formation of covers to protect and pump water over the gills. In a new study published in the Proceedings of the National Academy of the Sciences (PNAS), USC Stem Cell scientists and their collaborators have identified a key modification to the genome that led to the evolution of gill covers more than 430 million years ago.
The scientists started by creating zebrafish with mutations in a gene called Pou3f3. Strikingly, fish lacking this gene, or the DNA element controlling its activity in the gills, failed to form gill covers. Conversely, zebrafish producing too much Pou3f3 developed extra rudimentary gill covers. Read more…
Photo: A live adult zebrafish showing showing Pou3f3 gene activity (green) in the gill cover, jaw support skeleton, and eye. Bone-forming cells are labeled in magenta. (Image by Peter Fabian/USC Stem Cell)