Departamento de Biodiversidad y Biología Evolutiva, Museo Nacional de Ciencias Naturales (MNCN-CSIC), José Gutiérrez Abascal 2, 28006 Madrid, Spain.
Centre of Marine Sciences (CCMAR), Universidade do Algarve, Campus de Gambelas, 8005-139 Faro, Portugal.
Gigascience. 2022 Dec 28;12. doi: 10.1093/gigascience/giad075. Epub 2023 Sep 30.
Genomes are powerful resources to understand the evolutionary mechanisms underpinning the origin and diversification of the venoms of cone snails (Conidae: Caenogastropoda) and could aid in the development of novel drugs.
Here, we used PacBio continuous long reads and Omni-C data to assemble the chromosome-level genome of Kalloconus canariensis, a vermivorous cone endemic to the Canary Islands. The final genome size was 2.87 Gb, with a N50 of 79.75 Mb and 91% of the reads located into the 35 largest scaffolds. Up to 55.80% of the genome was annotated as repetitive regions, being class I of transposable elements (16.65%) predominant. The annotation estimated 34,287 gene models. Comparative analysis of this genome with the 2 cone snail genomes released to date (Dendroconus betulinus and Lautoconus ventricosus) revealed similar genome sizes and organization, although chromosome sizes tended to be shorter in K. canariensis. Phylogenetic relationships within subclass Caenogastropoda were recovered with strong statistical support. The family Conidae was recovered as a clade, with K. canariensis plus L. ventricosus sister to D. betulinus.
Despite the great diversity of cone snails (>900 species) and their venoms (hundreds of peptides per species), only 2 recently reported genomes are available for the group. The high-quality chromosome-level assembly of K. canariensis will be a valuable reference for studying the origin and evolution of conotoxin genes as well as whole-genome duplication events during gastropod evolution.
基因组是理解 cone snails（Conidae：Caenogastropoda）毒液起源和多样化背后的进化机制的有力资源，并且可以帮助开发新型药物。
在这里，我们使用 PacBio 连续长读和 Omni-C 数据组装了 Canary Islands 特有的食虫 cone snail Kalloconus canariensis 的染色体水平基因组。最终基因组大小为 2.87 Gb，N50 为 79.75 Mb，91%的reads 位于 35 个最大的支架中。多达 55.80%的基因组被注释为重复区域，其中 I 类转座元件（16.65%）占主导地位。该注释估计有 34,287 个基因模型。将该基因组与迄今为止发布的 2 个 cone snail 基因组（Dendroconus betulinus 和 Lautoconus ventricosus）进行比较分析，发现它们的基因组大小和组织相似，尽管 K. canariensis 的染色体大小往往较短。在次纲 Caenogastropoda 内的系统发育关系得到了强有力的统计支持。科 Conidae 被恢复为一个分支，K. canariensis 和 L. ventricosus 与 D. betulinus 姐妹关系。
尽管 cone snails（>900 种）及其毒液（每种毒液数百种肽）的多样性很大，但该组仅提供了最近报道的 2 个基因组。K. canariensis 的高质量染色体水平组装将是研究 conotoxin 基因起源和进化以及腹足动物进化过程中全基因组复制事件的有价值的参考。
