The Amur ide (Leuciscus waleckii) is a cyprinid fish that is widely distributed in Northeast Asia. The Lake Dali Nur population inhabits one of the most extreme aquatic environments on Earth, with an alkalinity up to 50 mmol/L (pH 9.6), thus providing an exceptional model with which to characterize the mechanisms of genomic evolution underlying adaptation to extreme environments. Here, we developed the reference genome assembly for L. waleckii from Lake Dali Nur. Intriguingly, we identified unusual expanded long terminal repeats (LTRs) with higher nucleotide substitution rates than in many other teleosts, suggesting their more recent insertion into the L. waleckii genome. We also identified expansions in genes encoding egg coat proteins and natriuretic peptide receptors, possibly underlying the adaptation to extreme environmental stress. We further sequenced the genomes of 10 additional individuals from freshwater and 18 from Lake Dali Nur populations, and we detected a total of 7.6 million SNPs from both populations. In a genome scan and comparison of these two populations, we identified a set of genomic regions under selective sweeps that harbor genes involved in ion homoeostasis, acid-base regulation, unfolded protein response, reactive oxygen species elimination, and urea excretion. Our findings provide comprehensive insight into the genomic mechanisms of teleost fish that underlie their adaptation to extreme alkaline environments.
Molecular Biology and Evolution – Oxford University Press
Published: Jan 1, 2017
It’s your single place to instantly
discover and read the research
that matters to you.
Enjoy affordable access to
over 18 million articles from more than
15,000 peer-reviewed journals.
All for just $49/month
Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly
Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place.
All the latest content is available, no embargo periods.
“Whoa! It’s like Spotify but for academic articles.”@Phil_Robichaud