Amur grayling genome files

Graylings (<i>Thymallus</i>) represent one of the earliest diverged salmonid subfamilies and provide crucial insights into the evolutionary consequences of the salmonid-specific whole genome duplication event (Ss4R). Here, we present the first chromosome-level genome assembly of the Amur grayling (<i>Thymallus grubii</i>), an economically and ecologically important species endemic to East Asian freshwater systems. The final assembly spans 1,754.51 Mb with 46 pseudo-chromosomes, achieving a contig N50 of 3.03 Mb and anchoring 99.97% of sequences to chromosomes. The genome contains 31,867 protein-coding genes with 97.58% functionally annotated. Repetitive sequences comprise 52.64% of the genome, dominated by DNA transposons (22.06%). BUSCO analysis indicates 97.9% completeness for conserved Actinopterygii genes. This high-quality genome assembly provides an essential resource for salmonid comparative genomics, aquaculture breeding programs, and conservation genetics of this economically important species.

茴鱼属（*Thymallus*）是分化最早的鲑科亚类群之一，为探究鲑类特异性全基因组复制事件（Ss4R）带来的演化后果提供了关键研究契机。本研究首次报道了黑龙江茴鱼（*Thymallus grubii*）的染色体级基因组组装结果——该物种是东亚淡水生态系统特有的、兼具经济与生态价值的重要物种。最终组装的基因组序列总长1754.51 Mb，包含46条伪染色体，重叠群N50达3.03 Mb，且99.97%的序列可锚定至染色体上。该基因组共注释得到31867个蛋白编码基因，其中97.58%完成了功能注释；重复序列占基因组总长度的52.64%，其中以DNA转座子（占比22.06%）为优势类型。BUSCO分析显示，该组装对保守辐鳍鱼纲基因的完整度达97.9%。本研究获得的高质量基因组组装，将为鲑类比较基因组学、该经济物种的水产养殖育种及保护遗传学研究提供不可或缺的基础资源。