Abstract
The salmonid-specific fourth vertebrate whole-genome duplication (Ss4R)
occurred ~80 million years ago in the ancestor of all
salmonids and provides a unique opportunity to study the evolutionary
history of the duplicated genome. Study of the genome ofBrachymystax
lenok tsinlingensis might be particularly insightful given that this is
the only Brachymystax species with a published salmonid genome.
Here, we present a high-quality chromosome-level genome assembly forB. l. tsinlingensis and found
that
the salmonids have a unique GC content and codon usage, have undergone a
whole-genome duplication event and a burst of transposon-mediated repeat
expansion, have a slower evolutionary rate, and possess specific
expanded gene families and unique positively selected genes. Generally,
the B. l. tsinlingensis genome could provide a valuable reference
for the study of other salmonids as well as aid the conservation of this
endangered species.