College of Bioscience and Biotechnology, Shenyang Agricultural University, Shenyang 110866, Liaoning Province, China.
J Agric Food Chem. 2023 Jul 19;71(28):10670-10682. doi: 10.1021/acs.jafc.3c02779. Epub 2023 Jun 18.
Herbivorous insects are well known for detoxifying a broad range of the defense compounds produced by the plants that they feed on, but knowledge of the mechanisms of detoxification is still very limited. Here, we describe a system in which two species of lepidopteran caterpillars metabolize an abietane diterpene from the plants of Diels to an oxygenated derivative that is less active biologically. We found that this transformation could be catalyzed by a cytochrome P450 enzyme in caterpillars, which are associated with molting. Most interestingly, abietane diterpene targets the molting-associated gene to alter the content of molting hormones in the insect at specific developmental stages and competitively inhibit molting hormone metabolism. These findings identify the mechanism by which caterpillars are able to detoxify abietane diterpenoid through hydroxylation at the C-19 position, which may be opening up exciting research questions into the mechanisms of interaction between plants and insects.
食草昆虫以能够代谢其食用的植物所产生的多种防御化合物而闻名，但目前对其解毒机制的了解仍然非常有限。在这里，我们描述了一个系统，其中两种鳞翅目毛毛虫将植物 Diels 中的一种枞酸二萜代谢为一种生物活性较低的含氧衍生物。我们发现，这种转化可以由毛毛虫中的细胞色素 P450 酶催化，这种酶与蜕皮有关。最有趣的是，枞酸二萜类化合物以蜕皮相关基因为靶点，改变昆虫在特定发育阶段的蜕皮激素含量，并竞争性抑制蜕皮激素代谢。这些发现确定了毛毛虫能够通过 C-19 位的羟化作用解毒枞酸二萜的机制，这可能为研究植物与昆虫之间相互作用的机制开辟了令人兴奋的研究课题。
