The Myb-p1 gene was isolated by screening for differentially expressed Myb-related genes in red (anthocyanin-producing) and green (anthocyanin nonproducing) forms of Perilla frutescens. Expression of Myb-p1 is increased 10-fold in the red relative to the green form of P. futescens, and the gene is induced by light. MYB-P1 has only one DNA-binding region, which corresponds to repeat III in the general structure of MYB proteins. In the yeast two-hybrid system, it was shown that MYB-P1 interacted with MYC-RP, a MYC-related transcriptional regulatory protein involved in the control of anthocyanin biosynthesis in P. frutescens. In yeast, MYB-P1 was able to bind to a dihydroflavonol reductase (DFR) gene promoter isolated from red P. frutescens. These data suggest that Myb-p1 may be involved in the regulation of anthocyanin biosynthesis and could therefore be responsible for determining anthocyanin formation in red P. frutescens.