Functions as a multidrug and toxin extrusion transporter in the export of salicylic acid (SA) from the chloroplast to the cytoplasm (PubMed:23757404). Plays an essential function in plant defense via the pathogen-induced salicylic acid (SA) accumulation (PubMed:11826312, PubMed:24594657). Acts also as a key component of the Age-related resistance (ARR) pathway (PubMed:11884688, PubMed:19694953, PubMed:24594657). Preferentially expressed in the epidermal cells. By salicylic acid, UV-C light and pathogens. Enhanced susceptibility to several bacterial pathogens and alterations in PR-1 gene expression (PubMed:9090877). No salicylic acid (SA) accumulation after pathogen inoculation and more susceptibility to both virulent and avirulent forms of Pseudomonas syringae and Peronospora parasitica (PubMed:10449575, PubMed:24594657). Age-related resistance (ARR)-defective (PubMed:11884688, PubMed:19694953). Defect in stomatal response during bacterial infection (PubMed:21998587). Belongs to the multi antimicrobial extrusion (MATE) (TC 2.A.66.1) family.