Manipulating a Single Transcription Factor, Ant1 Promotes Anthocyanin Accumulation in Barley Grains

Barley has abundant anthocyanin-rich accessions, which renders it an ideal model to investigate the regulatory mechanism of anthocyanin biosynthesis. This study functionally characterized two transcription factors: Ant1 and Ant2. Sequence alignment showed that the coding sequences of Ant1 and Ant2 are conserved among 11 colored hulless barley and noncolored barley varieties. The expression profiles of Ant1 and Ant2 were divergent between species, and significantly higher expression was found in two colored Qngke accessions. The co-expression of Ant1 and Ant2 resulted in purple pigmentation in transient transformation systems via the promotion of the transcription of four structural genes. Ant1 interacted with Ant2, and overexpression of Ant1 activated the transcription of Ant2. Moreover, overexpression of Ant1 led to anthocyanin accumulation in the pericarp and aleurone layer of transgenic barley grains. Overall, our results suggest that anthocyanin-enriched barley grains can be produced by manipulating Ant1 expression.

Automated summary

Barley has abundant accessions rich in anthocyanin, making it an ideal model for studying the regulatory mechanism of anthocyanin biosynthesis. Two transcription factors, Ant1 and Ant2, were characterized in this study, with their co-expression promoting anthocyanin accumulation in transgenic barley grains. Manipulating the expression of Ant1 can lead to the production of anthocyanin-enriched barley grains.