The African coelacanth genome provides insights into tetrapod evolution
Chris T. Amemiya, Jessica Alföldi, Alison P. Lee, Shaohua Fan, Hervé Philippe, Iain MacCallum, Ingo Braasch, Tereza Manousaki, Igor Schneider, Nicolas Rohner, Chris Organ, Domitille Chalopin, Jeramiah J. Smith, Mark Robinson, Rosemary A. Dorrington, Marco Gerdol, Bronwen Aken, Maria Assunta Biscotti, Marco Barucca, Denis Baurain, Aaron M. Berlin, Gregory L. Blatch, Francesco Buonocore, Thorsten Burmester, Michael S. Campbell et al.
Affiliations Contributions Corresponding authors
Nature 496, 311–316 (18 April 2013) doi:10.1038/nature12027
Received 05 September 2012 Accepted 20 February 2013 Published online 17 April 2013
Abstract
The discovery of a living coelacanth specimen in 1938 was remarkable, as this lineage of lobe-finned fish was thought to have become extinct 70 million years ago. The modern coelacanth looks remarkably similar to many of its ancient relatives, and its evolutionary proximity to our own fish ancestors provides a glimpse of the fish that first walked on land. Here we report the genome sequence of the African coelacanth, Latimeria chalumnae. Through a phylogenomic analysis, we conclude that the lungfish, and not the coelacanth, is the closest living relative of tetrapods. Coelacanth protein-coding genes are significantly more slowly evolving than those of tetrapods, unlike other genomic features. Analyses of changes in genes and regulatory elements during the vertebrate adaptation to land highlight genes involved in immunity, nitrogen excretion and the development of fins, tail, ear, eye, brain and olfaction. Functional assays of enhancers involved in the fin-to-limb transition and in the emergence of extra-embryonic tissues show the importance of the coelacanth genome as a blueprint for understanding tetrapod evolution.
Subject terms: Genome evolution Comparative genomics
