Brassica napus L. is an important oil crop in China. Most of the oil from B. napus is stored in oil bodies. In this study, the biogenesis of oil bodies and variations in the gene expression levels of oil body proteins and fatty acid synthesis transcription factors were characterized during embryogenesis using ultrastructural observations and quantitative polymerase chain reaction. When comparing the fluorescence intensities of Nile red staining in embryos at various stages, increasing numbers of oil bodies were observed in B. napus embryos after the globular embryo stage. Oil bodies were observed in early embryos in the embryo itself and in suspensors at 9–11 days after pollination (globular embryo stage) using ultrastructural analyses. There were more oil bodies in embryos at the torpedo-shaped embryo stage than at the heart-shaped embryo stage. In addition, the gene expression levels of oil body proteins, including oleosins, steroleosins, and BnCLO1, but not BnCLO3, increased during the heart-shaped embryo stage and these elevated levels were maintained during the subsequent developmental stages. The expression levels of fatty acid synthesis transcription factors (BnLEC1, BnL1L, BnWRI1, and BnFUS3) increased during the early stages and decreased during the later stages, while their peak expression times differed. Expression of BnLEC1 was the first to peak, followed by BnL1L, BnWRI1, and BnFUS3. We characterized oil body formation during the early embryonic development of B. napus, including the first examination of oil bodies in globular embryos. We also documented numerical variation in oil bodies during early embryogenesis, which was consistent with the gene expression levels of oil body proteins and fatty acid synthesis transcription factors.

欧洲油菜是我国重要的油料作物。来自欧洲油菜的大部分油储存在油体中。在这项研究中，油体的生物发生以及油体蛋白和脂肪酸合成转录因子的基因表达水平的变化在胚胎发生过程中使用超微结构观察和定量聚合酶链反应进行了表征。当比较不同阶段胚胎尼罗红染色的荧光强度时，在欧洲油菜中观察到越来越多的油体球状胚胎阶段后的胚胎。使用超微结构分析在授粉后 9-11 天（球状胚阶段）在胚胎本身的早期胚胎和悬柄中观察到油体。鱼雷形胚胎期的胚胎油体比心形胚胎期的多。此外，油体蛋白，油质蛋白，包括，steroleosins，和的基因表达水平BnCLO1，但不是BnCLO3，在心脏形胚阶段增加，并且在随后的发育阶段维持这些升高的水平。脂肪酸合成转录因子（BnLEC1、BnL1L、BnWRI1和BnFUS3）的表达水平) 在早期增加，在后期减少，但它们的峰值表达时间不同。BnLEC1 的表达首先达到峰值，其次是BnL1L、BnWRI1和BnFUS3。我们对欧洲油菜早期胚胎发育过程中油体的形成进行了表征，包括对球状胚胎中油体的第一次检查。我们还记录了早期胚胎发生过程中油体的数值变化，这与油体蛋白和脂肪酸合成转录因子的基因表达水平一致。