RT Journal Article
SR Electronic
T1 The grayling genome reveals selection on gene expression regulation after whole genome duplication
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 153270
DO 10.1101/153270
A1 Srinidhi Varadharajan
A1 Simen R. Sandve
A1 Ole K. Tørresen
A1 Sigbjørn Lien
A1 Leif Asbjørn Vøllestad
A1 Sissel Jentoft
A1 Alexander J. Nederbragt
A1 Kjetill S. Jakobsen
YR 2017
UL http://biorxiv.org/content/early/2017/06/22/153270.abstract
AB Whole genome duplication (WGD) has been a major evolutionary driver of increased genomic complexity in vertebrates, yet little is known about how selection operates on the resulting gene duplicates. Here, we present a draft genome assembly of a salmonid species, European grayling (Thymallus thymallus) and use comparative genomics and transcriptomics to understand evolutionary consequences of WGD in the genome of salmonid ancestor ~80 million years ago (Ss4R). We find evidence for lineage-specific rates in rediploidization and that ~60% of the Ss4R ohnologs have experienced different types of non-neutral evolution of tissue-specific gene expression regulation. Distinct selective pressures were associated with tissue type, biological function and selection pressure on protein coding sequence. Finally, our results indicate the role of adaptive divergence of Ss4R duplicates in the evolution of salmonid metabolism and identifies loss of purifying selection on one Ss4R ohnolog encoding a key chloride pump linked to the evolution of anadromy.