Background: Berberine is a plant-derived herbicidal alkaloid. The herbicidal mechanism of berberine is still not clear. In this study, our aim is to clarify the mechanism of berberine inhibiting the root growth of Arabidopsis thaliana, aiming at providing new insight into identifying the molecular targets of berberine.
Results: The whole-genome RNA sequencing had revealed that 403 genes were down-regulated, and 422 genes were up-regulated in Arabidopsis roots with berberine treatment. According to KEGG and GO analysis, the expression of two genes AT5G48010 (Thas) and AT5G42600 (MRN1) which are in the sesquiterpenoid and triterpenoid biosynthesis pathway were affected most. These two genes belong to thalianol and marneral gene clusters. RT-PCR showed that Arabidopsis responds to berberine by inhibiting root growth through repressing the expression of thalianol and marneral gene clusters, which was independent of the upstream effectors ARP6 and HTA9-1. GC-MS analysis showed that berberine could inhibit THAH in the biosynthetic network of triterpenoid gene cluster in Arabidopsis and thus cause the accumulation of thalianol.
Conclusion: Our study indicated the repression of the thalianol and marneral gene clusters as the primary mechanism of action of berberine in Arabidopsis, which may result in plant growth defects by interrupting the thalianol metabolic pathway. This provides novel clues as to the possible molecular herbicidal mechanism of berberine. © 2022 Society of Chemical Industry.
Keywords: Arabidopsis; berberine; gene cluster; marneral; thalianol.
© 2022 Society of Chemical Industry.