12485 10.30848/PJB2024-6(19) <p> MYC2 involves in erucic acid synthesis by negatively regulation <em>FAE1</em> transcription activity in <em>Brassica napus</em></p> Xi Jiang, Shouchuan Zhi, Jie Liu, Shixing Guo, Zhanping Yue, Xiaobing Pu, Yongcheng Wu and Zhuang Li <p> Erucic acid is a typical long-chain fatty acid, which is considered to human health but extensively applied in industry and other fields. MYC2 is the crucial regulator in the JA signaling pathway, which participates in plant response to insect, pathogenic bacteria and other stress. However, the involvement of MYC2 in other biological processes is unclear. In this study, we reported that BnMYC2 took part in erucic acid synthesis by directly binding to promoter of <em>BnFAE1</em> a major gene during the erucic acid synthesis in <em>Brassica napus</em>. GUS histochemistry assay showed that staining was observed in all detected tissues, especially in seed. The subcellular localization indicated that BnMYC2 was located in the nucleus. Yeast one-hybridization and double luciferase experiments indicated that <em>BnFAE1</em> transcription activity was regulated by BnMYC2 <em>In</em> <em>vitro </em>and <em>In</em> <em>vivo</em>, respectively. The results of genetic transformation verified that compared with WT, the expression level of <em>AtFAE</em>1 gene was significantly enhanced in the mutant <em>myc2-2</em>, and the same tendency was also found in mutant background. Unexpectedly, the opposite trend was observed in <em>BnMYC2</em>-overexpression Arabidopsis. Collectively, these results revealed that BnMYC2 played a essential role in erucic acid synthesis in oilseed rape. Our research provided a preliminary understanding of how erucic acid synthesis was modulated by JA signaling in <em>Brassica napus</em></p> Published 2024 56 6 2389 2398