Rapeseed (Brassica napus L.) is an important oil crop world-widely cultivated, and seed oil content (SOC) is one of the most important traits for rapeseed. To increase SOC, many efforts for promoting the function of genes on lipid biosynthesis pathway have been previously made. However, seed oil formation is a dynamic balance between lipid synthesis and breakdown. It is, therefore, also reasonable to weaken or eliminate the function of genes involved in lipid degradation for a higher final SOC. We applied a genome-wide association study (GWAS) on SOC in a collection of 290 core germplasm accessions. A total of 2,705,480 high-quality SNPs were used in the GWAS, and we identified BnaC07g30920D, a patatin-like lipase (PTL) gene, that was associated with SOC. In particular, six single-nucleotide-polymorphisms (SNPs) in the promoter region of BnaC07g30920D were associated with the significant reduction of SOC, leading to a 4.7–6.2% reduction of SOCs. We performed in silico analysis to show a total of 40 PTLs, which were divided into four clades, evenly distributed on the A and C subgenomes of Brassica napus. RNA-seq analysis unveiled that BnPTLs were preferentially expressed in reproductive tissues especially maturing seeds. We identified BnaC07g30920D, a BnPTL gene, that was associated with SOC using GWAS and performed in silico analysis of 40 PTLs in Brassica napus. The results enrich our knowledge about the SOC formation in rapeseed and facilitate the future study in functional characterization of BnPTL genes.

中文翻译：

---

全基因组关联研究揭示了与甘蓝型油菜种子油含量降低有关的马铃薯样脂肪酶

油菜籽（Brassica napus L.）是世界范围内栽培的重要油料作物，种子含油量（SOC）是油菜籽最重要的性状之一。为了增加SOC，之前已经做出了许多努力来促进脂质生物合成途径上的基因的功能。然而，种子油的形成是脂质合成和分解之间的动态平衡。因此，为了获得更高的最终 SOC，削弱或消除参与脂质降解的基因的功能也是合理的。我们对 290 个核心种质资源的 SOC 应用了全基因组关联研究 (GWAS)。GWAS 中总共使用了 2,705,480 个高质量 SNP，我们鉴定了 BnaC07g30920D，一种与 SOC 相关的 patatin 样脂肪酶 (PTL) 基因。特别是，BnaC07g30920D 启动子区域的 6 个单核苷酸多态性 (SNP) 与 SOC 的显着降低相关，导致 SOC 降低 4.7-6.2%。我们进行了计算机分析，显示总共 40 个 PTL，它们分为 4 个进化枝，均匀分布在甘蓝型油菜的 A 和 C 亚基因组上。RNA-seq 分析揭示，BnPTL 优先在生殖组织尤其是成熟种子中表达。我们使用 GWAS 鉴定了 BnaC07g30920D（一种 BnPTL 基因），该基因与 SOC 相关，并对甘蓝型油菜中的 40 个 PTL 进行了计算机分析。这些结果丰富了我们对油菜籽 SOC 形成的认识，并有助于未来 BnPTL 基因功能表征的研究。