Fig. 4

Expression levels of the structural and regulatory genes of the anthocyanin biosynthetic pathway. a-b Transcript levels of the structural (CHS, CHI, DFR, F3'H, LDOX, UF3GT, UGT75C1, and UGT75C2) and regulatory (PAP1, PAP2, TT8, and MYB11) genes involved in anthocyanin biosynthesis in the glk mutants (glk1, glk2, and glk1 glk2) and AtGLK1-overexpressing seedlings (c-d). Total RNA extracted from the 4-day-old wild-type (Col), glk mutants and AtGLK1-overexpressing (OEGLK1-1 and OEGLK1-2) seedlings was used for real-time quantitative PCR analyses. The asterisks indicate statistically significant differences compared with the corresponding wild-type (Student’s t test: *P < 0.05)