The blue king crab, Paralithodes platypus, which belongs to the family Lithodidae, is a commercially and ecologically important species. However, a high‐quality reference genome for the king crab has not yet been reported. Here, we assembled the first chromosome‐level blue king crab genome, which contains 104 chromosomes and an N50 length of 51.15 Mb. Furthermore, we determined that the large genome size can be attributed to the insertion of long interspersed nuclear elements and long tandem repeats. Genome assembly assessment showed that 96.54% of the assembled transcripts could be aligned to the assembled genome. Phylogenetic analysis showed the blue king crab to have a close relationship with the Eubrachyura crabs, from which it diverged 272.5 million years ago. Population history analyses indicated that the effective population of the blue king crab declined sharply and then gradually increased from the Cretaceous and Neogene periods, respectively. Furthermore, gene families related to developmental pathways, steroid and thyroid hormone synthesis, and inflammatory regulation were expanded in the genome, suggesting that these genes contributed substantially to the environmental adaptation and unique body plan evolution of the blue king crab. The high‐quality reference genome reported here provides a solid molecular basis for further study of the blue king crab's development and environmental adaptation.

中文翻译：

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Paralithodes 鸭嘴兽的染色体水平基因组组装为帝王蟹的进化和适应提供了见解

蓝帝王蟹，Parlithodes 鸭嘴兽属于 Lithodidae 科，是一种具有重要商业和生态意义的物种。然而，尚未报道过帝王蟹的高质量参考基因组。在这里，我们组装了第一个染色体水平的蓝帝王蟹基因组，其中包含 104 条染色体和 51.15 Mb 的 N50 长度。此外，我们确定大基因组大小可归因于长散布核元件和长串联重复序列的插入。基因组组装评估表明，96.54% 的组装转录本可以与组装的基因组对齐。系统发育分析表明，蓝帝王蟹与真脉蟹亲缘关系密切，2.725 亿年前与真脉蟹发生了分化。种群历史分析表明，蓝帝王蟹的有效种群分别从白垩纪和新近纪开始急剧下降，然后逐渐增加。此外，与发育途径、类固醇和甲状腺激素合成以及炎症调节相关的基因家族在基因组中得到扩展，表明这些基因对蓝帝王蟹的环境适应和独特的体型进化做出了重大贡献。这里报告的高质量参考基因组为进一步研究蓝帝王蟹的发育和环境适应提供了坚实的分子基础。和炎症调节在基因组中得到扩展，表明这些基因对蓝帝王蟹的环境适应和独特的体型进化做出了重大贡献。这里报告的高质量参考基因组为进一步研究蓝帝王蟹的发育和环境适应提供了坚实的分子基础。和炎症调节在基因组中得到扩展，表明这些基因对蓝帝王蟹的环境适应和独特的体型进化做出了重大贡献。这里报告的高质量参考基因组为进一步研究蓝帝王蟹的发育和环境适应提供了坚实的分子基础。