PDF(Pubmed)
Abstract：
China leads the world in freshwater pearl production, an industry in which the triangle sail mussel (Sinohyriopsis cumingii) plays a pivotal role. In this paper, we report a high-quality chromosome-level genome assembly of S. cumingii with a size of 2.90 Gb-the largest yet reported among bivalves-and 89.92% anchorage onto 19 linkage groups. The assembled genome has 37,696 protein-coding genes and 50.86% repeat elements. A comparative genomic analysis revealed expansions of 752 gene families, mostly associated with biomineralization, and 237 genes under strong positive selection. Notably, the fibrillin gene family exhibited gene family expansion and positive selection simultaneously, and it also exhibited multiple high expressions after mantle implantation by transcriptome analysis. Furthermore, RNA silencing and an in vitro calcium carbonate crystallization assay highlighted the pivotal role played by one fibrillin gene in calcium carbonate deposition and aragonite transformation. This study provides a valuable genomic resource and offers new insights into the mechanism of pearl biomineralization.
摘要：
中国淡水珍珠产量居世界前列,三角帆贻贝（Sinohyiriopsiscumgii）在其中起着举足轻重的作用的行业。在本文中,我们报道了一个高质量的CumgiiS的染色体水平基因组组装,其大小为2.90Gb,是双壳类动物中迄今报道的最大大小,89.92%锚定到19个连锁群.组装的基因组具有37,696个蛋白质编码基因和50.86%的重复元件。比较基因组分析显示752个基因家族的扩展，主要与生物矿化有关，和237个基因在强正向选择下。值得注意的是,原纤维蛋白基因家族同时表现出基因家族扩展和正选择，通过转录组分析，它在地幔植入后也表现出多种高表达。此外，RNA沉默和体外碳酸钙结晶测定强调了一个纤丝蛋白基因在碳酸钙沉积和文石转化中的关键作用。这项研究提供了宝贵的基因组资源，并为珍珠生物矿化机制提供了新的见解。
