Functions as a multidrug and toxin extrusion transporter that negatively regulates plant disease resistance (PubMed:21762165). Plays an important role in maintaining normal plant architecture, possibly by regulating local auxin biosynthesis (PubMed:24391508). May act as a negative regulator of hypocotyl cell elongation in the light (PubMed:26160579). Expressed in the meristematic regions. Mainly detected in tissues where cells were actively dividing, such as leaf primordia and young leaves, the junction between lateral root and the primary root, root cap, hydathodes, the junction between secondary inflorescence and the main inflorescence, young stamen and young siliques (PubMed:24391508). Highly expressed at the junction between the hypocotyl and the root, and at the marginal areas of cotyledons and true leaves, coinciding with the locations of the hydathode. Also highly expressed at the basal regions of the newly emerged lateral roots. In the floral organs, mostly expressed at the style of the pistil (PubMed:26160579). Enhanced resistance to bacterial pathogen PstDC3000 in RNAi mutant. Overexpression of DTX51 alters shoot developmental programs leading to a loss of apical dominance phenotype. Belongs to the multi antimicrobial extrusion (MATE) (TC 2.A.66.1) family.