The - Gene Cascade Induces Anthocyanin Accumulation by Regulating Sucrose Levels.

Anthocyanin accumulation specifically depends on sucrose (Suc) signaling/levels. However, the gene cascades specifically involved in the Suc signaling/level-mediated anthocyanin biosynthetic pathway are still unknown. (), a transcription coactivator, is involved in the regulation of leaf shape and drought tolerance. Recently, an gene cascade has been reported to regulate the light signaling-mediated anthocyanin accumulation. Target gene analysis indicates that is associated with the () promoter, a mitogen-activated protein kinase kinase kinase, for inducing anthocyanin accumulation. Indeed, loss-of-function mutants of showed significantly increased anthocyanin accumulation. mutation can also suppress the decrease in anthocyanin accumulation. Further analysis indicates that the mutations of and disrupt the normal Suc levels because of the changes of invertase activity in mutants of or , which in turn induces the alterations of anthocyanin accumulation in mutants of or via unknown regulatory mechanisms.