Analysis of coumarin content and key enzyme genes expression involved in coumarin biosynthesis from Peucedanum praeruptorum Dunn at different stages

Abstract

The accumulation of pyranocoumarins, the main active ingredient of Peucedanum praeruptorum Dunn, is strictly regulated by key enzyme genes in the coumarin biosynthesis pathway. However, little is understood about the correlation between the expression of key enzyme genes and the accumulation of coumarin content at various growth and development phases. In this work, a high-performance liquid chromatographic method and the real-time quantitative PCR system were prepared to establish the pyranocoumarins contents and the key enzyme expression in the roots, stems, and leaves of Peucedanum praeruptorum Dunn. The results showed that the coumarin content in the roots was the highest before blotting and was the lowest after flowering. Particularly, the content of Praeruptorin A, Praeruptorin B and Praeruptorin E was reduced to the lowest in roots after flowering. Consistent with the variation trend of the coumarin content in the stem, the relative expression of most key enzyme genes in the coumarin synthesis pathway was also significantly decreased. Especially for PpBMT gene, the relative expression in roots were extremely significantly decreased up to 90%. However, the variation trend of the coumarin content and the key enzyme genes expression was opposite in the roots and leaves. These results contribute to our knowledge of the process by which important enzymes control the production and accumulation of coumarin.