Biosynthesis, regulation and herbivore defense function of triterpenes from <em>Nicotiana attenuata</em>

In this study, the biosynthesis, regulation, and defense function of triterpenes in a wild tobacco plant Nicotiana attenuata were elucidated. We discovered that two oxidosqualene cyclases, NaOSC1 and NaOSC2, are involved in the synthesis of the triterpenoid skeleton in N. attenuata. Moreover, both of these genes participate in the defense against herbivores in N. attenuata. We also found that a specific JAZe/h-MYC2 complex modulates NaOSC1- but not NaOSC2-mediated triterpene biosynthesis in response to the infestation by herbivores