9,10-环甲基十七烷酸诱导灵芝三萜酸合成的信号转导和基因表达分析

为探究9,10-环甲基十七烷酸（9,10-CMA）诱导灵芝三萜酸合成的相关信号机制,分析了NO信号的介导作用。结果表明,在NO信号分子介导下,9,10-CMA可有效地刺激灵芝菌丝体中三萜合成关键酶细胞色素CYP450和苯丙氨酸解氨酶（PAL）的活化以及三萜酸的合成。NO可作为灵芝菌丝体中CYP450产生和PAL活化的上游分子发挥作用。在9,10-CMA诱导下,通过荧光定量PCR分析了6个关键酶基因在灵芝三萜酸合成过程的动态表达。结果表明,在9,10-CMA诱导下与灵芝三萜酸合成相关的角鲨烯合成酶基因sqs、细胞色素P450单加氧酶CYP5150L8基因和3‐羟基‐3‐甲基戊二酰辅酶A还原酶基因hmgr的上调最显著,提示这3个酶在三萜诱导过程中具有重要作用。

Signal transduction and gene expression analysis of triterpenoid acid synthesis induced by 9,10-cyclomethylheptadecanoic acid in Ganoderma lingzhi

In order to study the signal mechanism of 9,10-cyclomethylheptadecanoic acid (9,10-CMA) - induced triterpenoid acid (TA) synthesis in Ganoderma lingzhi, the mediating role of NO signal was analyzed. The results showed that under the induction of 9,10-CMA, NO could effectively trigger the activation of phenylalanine ammonia lyase (PAL) and cytochrome CYP450, and the synthesis of triterpenoid acids in G. lingzhi mycelia. Nitric oxide plays an inducer as a upstream molecule of CYP450 and PAL activating in G. lingzhi cell, but it is not the only signal molecule. The dynamic expression of six key enzymes in triterpenoid acid synthesis induced by 9,10-CMA in G. lingzhi was analyzed. The results showed that sqs, CYP5150L8 and hmgr genes related to triterpenoid acid synthesis in G. lingzhi were significantly up-regulated under 9,10-CMA induction, indicating that these three corresponding synthetases may play critical roles in the induction process.