RT Journal Article
SR Electronic
T1 Caecilian genomes reveal molecular basis of adaptation and convergent evolution of limblessness in snakes and caecilians
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 2022.02.23.481419
DO 10.1101/2022.02.23.481419
A1 Vladimir Ovchinnikov
A1 Marcela Uliano-Silva
A1 Mark Wilkinson
A1 Jonathan Wood
A1 Michelle Smith
A1 Karen Oliver
A1 Ying Sims
A1 James Torrance
A1 Alexander Suh
A1 Shane A. McCarthy
A1 Richard Durbin
A1 Mary J. O’Connell
YR 2022
UL http://biorxiv.org/content/early/2022/02/25/2022.02.23.481419.abstract
AB We present genome sequences for Geotrypetes seraphini (3.8Gb) and Microcaecilia unicolor (4.7Gb) caecilians, a limbless, mostly soil-dwelling amphibian clade with reduced eyes, and unique putatively chemosensory tentacles. We identify signatures of positive selection unique to caecilians in 1,150 orthogroups, with enrichment of functions for olfaction and detection of chemical signals. All our caecilian genomes are missing the ZRS enhancer of Sonic Hedgehog, shown by in vivo deletions to be required for limb development in mice and also absent in snakes, thus revealing a shared molecular target implicated in the independent evolution of limblessness in snakes and caecilians.Competing Interest StatementThe authors have declared no competing interest.