Horticulture Research (Mar 2019)
MdGSTF6, activated by MdMYB1, plays an essential role in anthocyanin accumulation in apple
Abstract
Intracellular transport: Identifying how apple pigment is sent for storage The mystery of how pigmenting anthocyanins are transported to intracellular storage is starting to be revealed. Alongside giving fruit their color, anthocyanins confer benefits to plant and human health. Glutathione S-transferases (GSTs) are responsible for transporting anthocyanins to storage vacuoles, yet research is lacking on how GSTs are regulated. Xuesen Chen, from China’s Shandong Agricultural University, and his team analyzed the activity of 23 GST genes in apple, finding one, MdGSTF6, was most highly active in the fruit-coloration stage of apple development. MdGSTF6 expression correlated with fruit anthocyanin levels and also restored anthocyanin levels in transport-suppressed plants, confirming its function. Chen’s team then discovered that MdGSTF6 expression is activated by the protein MdMYB1. The MdMYB1 gene is the major regulatory gene in anthocyanin synthesis, and is now revealed to also influence their transport.