Fig. 6

Proposed model of the molecular mechanisms and the proanthocyanin-anthocyanin biosynthesis pathways in Tibetan hulless barley. The structural enzymes are identified using large red capital letters; the encoding gene IDs are shown in small capital letters and are also in red if these genes are significantly differentially expressed between the two varieties. Red boxes and arrows correspond to TFs that are significantly positively correlated with, and thus may positively regulate, genes encoding structural enzymes. Green boxes and arrows correspond to TFs that are significantly negatively correlated with, and thus may negatively regulate, genes encoding structural enzymes