Tyrosine Induces Anthocyanin Biosynthesis in <i>Arabidopsis thaliana</i>

Abstract

Anthocyanins are widely found in plants and are responsible for the purple coloration of plants. Anthocyanin biosynthesis is induced by environmental stresses, plant hormones, sugar, and so on. Tyrosine (Tyr) is the pre cursor of melanin that exits in both animals and plants. However, until now it has been unknown whether Tyr induces anthocyanin biosynthesis. In this study , the seedlings of Arabidopsis thaliana were treated with exoge nous Tyr and then the anthocyanin accumulation was determined. The results showed that Tyr induced antho cyanin accumulation in Arabidopsis thaliana in a dose-dependent manner. Furthermore, the expression of the late anthocyanin biosynthetic genes including DFR , LDOX , and UF 3 GT , and the transcription factor genes PAP 1, PAP 2, and EGL 3 was induced by Tyr. Take n together, these results demonstrated that Tyr is able to induce an thocyanin accumulation and suggested that Tyr up-regulates transcription factors PAP 1, PAP 2, and EGL 3, which mediates the expression of the late anthocyanin biosynthetic genes and then induces anthocyanin biosyn thesis.