Multidrug and toxin efflux transporter involved in flavonoid metabolism. Required for proper reproductive development. A number of isoforms are produced. According to EST sequences. Highly expressed in inflorescence tissues, especially in floral epidermal guard cells including those of the anthers, stigma, siliques and nectaries. Also detected in the meristematic zone of the root apex and in the elongation zone through to the fully expanded cells of the differentiation zone. Affected flavonoid levels in the plant. Altered root growth, seed development and germination, and pollen development and release (PubMed:19995827). Enhanced growth and early flowering in comparison to the wild type (PubMed:20505354). Belongs to the multi antimicrobial extrusion (MATE) (TC 2.A.66.1) family.