The ref4-3 mutant interferes with the ability of MYB75 to drive anthocyanin production and PAL1 expression.
A, HPLC chromatograms of anthocyanins in 3-week-old rosette leaves of pap1-D and ref4-3 pap1-D plants grown in parallel. B, quantification of PAL1 transcript levels from 3-week-old rosette leaves of wild-type, pap1-D, ref4-3, and ref4-3 pap1-D plants, relative to the reference gene At1g13320.