外源鲨烯和茉莉酸甲酯对印楝素生物合成代谢网络的影响

Metabolic profiling analysis of azadirachtin in Azadirachta indica(neem)callus elicited by squalene and methyl jasmonate

基于广泛靶向代谢组技术,以印楝愈伤组织为材料,研究了外源鲨烯和茉莉酸甲酯(Me J)处理对印楝素生物合成代谢网络的影响。通过饲喂印楝愈伤组织鲨烯和茉莉酸甲酯,结合超高效液相色谱和质谱分析手段,对饲喂处理后的印楝愈伤组织代谢物进行定性定量分析。结果表明,Me J和鲨烯显著影响印楝愈伤组织的代谢活动,Me J处理后共检132种差异代谢物,包括52种初生代谢物和80种次生代谢物。Me J调控有机酸、脂质、氨基酸以及黄酮类和酚类物质的代谢,抑制印楝素B、诺米林和葫芦素E的合成。鲨烯处理检出137种差异代谢物,32种代谢物表达上调。Me J和鲨烯均显著促进印楝素A、Azadiradione、Nimbin和Salannin的合成,抑制印楝素B和D的合成。初步阐明了Me J和鲨烯影响印楝素A合成的机制,即二者通过调控初级代谢途径,影响印楝素合成前体的供给;通过抑制固醇类物质的次生代谢,促使更多的前体进入印楝素A合成的代谢流,进而调控印楝素的生物合成。

Based on extensive targeted metabonomics,the effects of azadirachtin biosynthetic networks treated with squalene and methyl jasmonate(MeJ)in Azadirachta indica(neem)callus were studied.By feeding squalene and MeJ from neem callus,combined with ultra-high performance liquid chromatography and mass spectrometry analysis methods,the metabolites of neem callus after feeding treatment were analyzed qualitatively and quantitatively.The results showed that MeJ and squalene significantly affected the metabolic of neem callus.A total of 132 different metabolites were identified after MeJ treatment,including 52 primary metabolites and 80 secondary metabolites.MeJ regulates the metabolism of organic acids,lipids,amino acids,flavonoids and phenols,and inhibits the synthesis of azadirachtin B,nomilin and cucurbitacin E.In squalene treatment,137 different metabolites were detected,and 32 metabolites were up-regulated.MeJ and squalene significantly promoted the synthesis of azadiradione,nimbin and salannin,and inhibited the synthesis of azadiradione B and D.The regulation mechanism of azadirachtin A biosynthesis by MeJ and squalene was preliminarily elucidated.The supply of precursors were affected by regulating the primary metabolic pathway while inhibited the secondary metabolism of sterols.Therefore,more precursors entered the metabolic flow of azadirachtin A biosynthesis.