Fig. 4.

a Differential expression of genes involved in phenylpropanoid/flavonoid biosynthesis pathway hormone signal transduction pathway in ‘Red Delicious’ and its four generation mutants (‘Starking Red’, ‘Starkrimson’, ‘Campbell Redchief’ and ‘Vallee spur’), named G0 to G4. Differential expression of transcription factors that encode MYB-like (b) and helix-loop-helix (c) DNA-binding domains. Heat maps depict the normalized gene expression values, which represent the means ± SD of three biological replicates. Expression values of five libraries are presented as FPKM normalized log₁₀-transformed counts