The Japanese silk moth, Antheraea yamamai, draft genome sequence

Antheraea yamamai, also known as the Japanese oak silk moth, is a wild species of silk moth. Silk produced by A. yamamai, referred to as tensan silk, shows different characteristics such as thickness, compressive elasticity and chemical resistance compared to the common silk produced from the domesticated silkworm, Bombyx mori. Its unique characteristics have led to its use in many research fields including biotechnology and medical science, and the scientific as well as economic importance of wild silk moth continues to gradually increase. However, no genomic information for wild silk moth, including A. yamamai, is currently available.
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In order to construct the A. yamamai genome, a total of 147G base pairs using Illumina and Pacbio sequencing platforms were generated, providing 210-fold coverage based on the 700 Mb estimated genome size of A. yamamai. The assembled genome of A. yamamai was 656 Mb(&gt;2kb) with 3,675 scaffolds and the N50 length of assembly was 739 Kb with 34.07% GC ratio. Identified repeat elements covered 37.33% of the total genome and the completeness of the constructed genome assembly was estimated to be 96.7% by BUSCO v2 analysis. A total of 15,481 genes were identified using Evidence Modeler based on the gene prediction results obtained from 3 different methods (ab initio, RNA-seq based, known-gene based) and manual curation.
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Here we present the genome sequence of A. yamamai, the first genome sequence of wild silk moth. These results provide valuable genomic information which will help enrich our understanding of the molecular mechanisms related to not only specific phenotypes such as wild silk itself but also the genomic evolution of Saturniidae.

天蚕（Antheraea yamamai），又称日本柞蚕（Japanese oak silk moth），是一种野生蚕蛾物种。天蚕产的蚕丝被称为天蚕丝绸（tensan silk），与家蚕（Bombyx mori）产的普通蚕丝相比，在厚度、压缩弹性及化学抗性等方面具有不同特性。其独特性质使其在生物技术、医学等多个研究领域得到应用，野生蚕蛾的科学及经济重要性正逐渐提升。然而，目前尚无包括天蚕在内的野生蚕蛾基因组信息。<br><br>为构建天蚕基因组，研究人员利用Illumina和Pacbio测序平台共生成147G碱基对数据，基于天蚕预估700 Mb的基因组大小，覆盖度达210倍。组装得到的天蚕基因组大小为656 Mb（>2kb），包含3675个支架序列（scaffolds），组装的N50长度为739 Kb，GC比例为34.07%。鉴定出的重复元件占基因组总量的37.33%，通过BUSCO v2分析，该基因组组装的完整性为96.7%。基于从头预测（ab initio）、RNA-seq辅助预测及已知基因同源预测三种方法的结果，并结合人工校正，利用Evidence Modeler共鉴定出15481个基因。<br>本文首次报道了天蚕的基因组序列，这也是野生蚕蛾的首个基因组序列。这些结果提供了宝贵的基因组信息，不仅有助于深入理解野生蚕丝等特定表型相关的分子机制，还将推动大蚕蛾科（Saturniidae）的基因组进化研究。