SmSPL6 Induces Phenolic Acid Biosynthesis and Affects Root Development in .

is a renowned model medicinal plant species for which 15 family genes have been identified; however, the specific functions of have not been well characterized as of yet. For this study, the expression patterns of were determined through its responses to treatments of exogenous hormones, including indole acetic acid (IAA), gibberellic acid (GA), methyl jasmonic acid (MeJA), and abscisic acid (ABA). To characterize its functionality, we obtained ovexpressed transgenic plants and found that overexpressed promoted the accumulation of phenolic acids and repressed the biosynthesis of anthocyanin. Meanwhile, the root lengths of the -overexpressed lines were significantly longer than the control; however, both the fresh weights and lateral root numbers decreased. Further investigations indicated that SPL6 regulated the biosynthesis of phenolic acid by directly binding to the promoter regions of the enzyme genes and and activated their expression. We concluded that SPL6 regulates not only the biosynthesis of phenolic acids, but also the development of roots in .