Transcriptional differences provide insight into environmental acclimatization in wild amur ide (Leuciscus waleckii) during spawning migration from alkalized lake to freshwater river.

Amur ide (Leuciscus waleckii) inhabits alkaline water in Lake Dali Nur and migrates to fresh water river for spawning every year. To investigate the potential genetic mechanisms underlying their alkaline acclimation, adaptation, and spawning migration, we performed differential gene expression analysis using high-throughput RNA-Seq data from liver of Amur ide samples collected before and after spawning migration. First, the short RNA-Seq reads were de novo assembled into 44,318 contigs, and provided the transcriptome reference sequences. Differential gene expression analysis identified 2575 genes with significant differential expression (p-value ≤.01, log2-fold-change ≥2). GO enrichment and KEGG pathway analyses were subsequently performed to determine gene functions and regulation. The results indicated that there were numerous differentially expressed genes involved in acid-base regulation, nitrogenous waste excretion, sexual maturation and reproduction, and stress response. These results provide fundamental information for further analyses of the physiological and molecular mechanisms underlying Amur ide alkaline acclimation, adaptation, and spawning migration.