Wang Qing, Liu Heng, Zhang Min, Liu Shaohua, Hao Yujin, Zhang Yuanhu
State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an, China.
College of Horticulture Science and Engineering, Shandong Agricultural University, Tai'an, China.
Front Plant Sci. 2020 Sep 2;11:512844. doi: 10.3389/fpls.2020.512844. eCollection 2020.
α-Farnesene, a sesquiterpene volatile compound plays an important role in plant defense and is known to be associated with insect attraction and with superficial scald of apple and pear fruits during cold storage. But the mechanism whereby transcription factors regulate apple α-farnesene biosynthesis has not been clarified. Here, we report that two transcription factors, MdMYC2 and MdERF3 regulated α-farnesene biosynthesis in apple fruit. Dual-luciferase assays and Y1H assays indicated that MdMYC2 and MdERF3 effectively trans-activated the promoter. EMSAs showed that MdERF3 directly binds the DRE motif in the promoter. Subsequently, overexpression of and in apple calli markedly activated the transcript levels of and . Furthermore, transient overexpression of and in apple fruit significantly increased expression and hence, α-farnesene production. These results indicate that MdMYC2 and MdERF3 are positive regulators of α-farnesene biosynthesis and have important value in genetic engineering of α-farnesene production.
α-法尼烯是一种倍半萜挥发性化合物，在植物防御中起重要作用，已知其与昆虫吸引以及苹果和梨果实冷藏期间的表面烫伤有关。但是转录因子调控苹果α-法尼烯生物合成的机制尚未阐明。在此，我们报道了两个转录因子MdMYC2和MdERF3调控苹果果实中的α-法尼烯生物合成。双荧光素酶测定和酵母单杂交测定表明，MdMYC2和MdERF3有效地反式激活了启动子。电泳迁移率变动分析表明，MdERF3直接结合启动子中的DRE基序。随后，在苹果愈伤组织中过表达MdMYC2和MdERF3显著激活了α-FAR和TPS10的转录水平。此外，在苹果果实中瞬时过表达MdMYC2和MdERF3显著增加了α-FAR表达，从而增加了α-法尼烯的产生。这些结果表明，MdMYC2和MdERF3是α-法尼烯生物合成的正调控因子，在α-法尼烯生产的基因工程中具有重要价值。
