A multidrug resistance-associated protein involved in anthocyanin transport in Zea mays

Abstract

Anthocyanin biosynthesis is one of the most thoroughly studied enzymatic pathways in biology, but little is known about the molecular mechanisms of its final stags: the transport of the anthocyanin pigment into the vacuole. We have identified a multidrug resistance-associated protein (MRP), ZmMrp3, that is required for this transport process in maize (Zea mays). ZmMrp3 expression is controlled by the regulators of anthocyanin biosynthesis and mirrors the expression of other anthocyanin structural genes. Localization of ZmMRP3 in vivo shows its presence in the tonoplast, the site at which anthocyanin transport occurs. Mutants generated using antisense constructs have a distinct pigmentation p..