背景回顾：Sugar is considered as the primary regulator of plant apical dominance, whereby the outgrowth of axillary buds is inhibited by the shoot tip. 

提出问题：However, there are some deficiencies in this theory.

主要发现：Here, we reveal that Fatty Acid Export 6 (BnFAX6) functions in fatty acid transport, and linoleic acid or its derivatives acts as a signaling molecule in regulating apical dominance of Brassica napus. 

结果1-BnFAX6功能：BnFAX6 is responsible for mediating fatty acid export from plastids. Overexpression of BnFAX6 in Brassica napus heightened expression of genes involved in glycolysis and lipid biosynthesis, promoting the flow of photosynthetic products to the biosynthesis of fatty acids (including linoleic acid and its derivatives). 

结果2-过表达植株表型：Enhancing expression of BnFAX6 increased oil content in seeds and leaves and resulted in semi-dwarf and increased branching phenotypes with more siliques, contributing to increased yield per plant relative to wild type. 

结果3-过表达与去顶表型一致：Furthermore, decapitation led to the rapid flow of the carbon from photosynthetic products to fatty acid biosynthesis in axillary buds, consistent with the overexpression of BnFAX6 in Brassica napus. Additionally, free fatty acids, especially linoleic acid, were rapidly transported from leaves to axillary buds. 

结果4-下游机制：Increasing linoleic acid in axillary buds repressed expression of a key transcriptional regulator responsible for maintaining bud dormancy, resulting in bud outgrowth. 

结论：Taken together, we uncovered that BnFAX6 mediating fatty acid export from plastids functions in lipid biosynthesis and in axillary bud dormancy release, possibly through enhancing linoleic acid level in axillary buds of Brassica napus.

 摘 要 

植物的顶端优势现象指的是茎尖抑制腋芽生长，而糖被认为是该现象的主要调节因子。然而，这一理论也存在一些不足。本文中，作者发现BnFAX6蛋白作用于脂肪酸的转运，而亚油酸或其衍生物在油菜（Brassica napus）的顶端优势调控中作为信号分子发挥作用。BnFAX6负责介导质体的脂肪酸输出。BnFAX6在油菜中的过表达增强了糖酵解和脂质合成相关基因的表达，促进了光合产物向脂肪酸（包括亚油酸及其衍生物）生物合成的转化。相比于野生型，BnFAX6基因表达的增强，增加了油菜种子和叶片的含油量，导致植株半矮化和分枝、角果增多的表型，有助于提高单株的产量相。此外，油菜去头处理导致了碳从光合产物快速流向腋芽中的脂肪酸生物合成，这与油菜中BnFAX6过表达的表型一致。另外，游离脂肪酸，尤其是亚油酸，从叶片迅速转移至腋芽。腋芽中亚油酸含量的增加，抑制了一个负责维持芽的休眠的关键转录调节因子的表达，从而导致芽的向外生长。综上所述，本文的研究结果揭示了BnFAX6通过介导质体脂肪酸的输出，可能通过提高油菜腋芽中的亚油酸水平，在油脂合成和腋芽休眠解除中发挥作用。