Figure 5. Integration of gene expression and metabolite changes of flavonoids pathway.

(A) Simplified map of anthocyanin biosynthesis pathway modified from Petroni et al.²¹. The font style of the identified metabolites were set to be bold. PAL, phenylalanine ammonia lyase; C4H, cinamic acid 4-hydroxylase; 4CL, 4-coumarate CoA ligase; CHS, chalcone synthase; CHI, chalcone isomerase; DFR, dihydroflavonol reductase; F3′H, flavanone 3′-hydroxylase; F3H, flavanone 3-hydroxylase; F3′5′H, flavonoid 3′,5′-hydroxylase; ANS, anthocyanidin synthase; UFGT, UDP-flavonoid glucosyl transferase; FNS, flavone synthase; FLS, flavonol synthase; LAR, leucoanthocyanidin reductase; ANR, anthocyanidin reductase. B, Changes in metabolite levels in maize kernels along the development. *denotes the metabolite level at II (16 DAP) or III (21 DAP) was significantly different from that at I (11 DAP) of the same cultivar. Black and purple stars denote SW48 and SW93, respectively. C, Changes in expression levels of genes involved in flavonoids pathway as revealed by qRT-PCR. C1, colored aleurone 1 or colorless1; R1, red color 1. The y-axis represents the relative abundance of each gene. The mean expression level of each gene at I of SW48 was denoted as 1. CHS: GRMZM2G422750 and GRMZM2G151227; CHI-1: GRMZM2G119186; CHI-2: GRMZM2G155329; DFR: GRMZM2G026930 and GRMZM2G013726; F3H: GRMZM2G062396. C1: GRMZM2G005066; R1: GRMZM5G822829. D, Changes in expression levels of genes involved in flavonoids pathway as revealed by RNA-Seq. The y-axis represents the counts of genes in SW93 and SW48 by RNA-Seq. The detailed expression profile of each gene was shown in Supplementary Table S8.