MdGSTF6, activated by MdMYB1, plays an essential role in anthocyanin accumulation in apple.

Anthocyanins are biosynthesized on the cytosolic surface of the endoplasmic reticulum and then transported into the vacuole for storage. Glutathione -transferases (GSTs) are considered to be responsible for the transport of anthocyanins into the vacuole. However, the regulatory mechanisms of GSTs in plants are still unclear. Here, we performed a genome-wide analysis and identified 69 genes in apple. The expression of was positively correlated with the anthocyanin content ( = 0.949) during 'Yanfu 8' fruit development. The overexpression of in the mutant resulted in seedlings of 35S::-GFP/ that could accumulate anthocyanin and rescue its phenotype, suggesting that MdGSTF6 was an anthocyanin transporter. The silencing of affected anthocyanin accumulation in apple fruit. Moreover, the knockdown of by RNA interference in cultured 'Gala' seedlings inhibited anthocyanin accumulation. The interaction experiments showed that MdMYB1 could bind directly to the promoter to transcriptionally activate its expression. Collectively, our results demonstrate that encodes an important GST transporter of anthocyanins in apple fruit and provide evidence for the associated regulatory mechanisms. Therefore, MdMYB1 can not only regulate anthocyanin synthesis, but also control the transport of anthocyanin in apples. This information may be useful for further clarifying the regulation of anthocyanin transport in apple.