Involved in the secretion of cuticular wax from epidermal cells to the cuticle, especially in the transport of aldehydes, alcohols and acids. (Microbial infection) Required for the polarization of reflected light on both adaxial and abaxial leaves surfaces upon viral infection by Turnip vein clearing virus (TVCV), probably by regulating cuticular wax compounds deposition, thus influencing visual attractiveness of infected plants for insect vectors. Forms heterodimers with ABCG11 in epidermal cells. Trafficking to the plasma membrane is dependent of ABCG11. Exclusively and constitutively expressed in epidermal cells. By NaCl and abscisic acid (ABA). Abnormal cuticle and unusual lipidic cytoplasmatic inclusions in epidermal cells associated with a reduced secretion of aldehydes, alcohols and acids (PubMed:17951461, PubMed:26965486). The double mutant abcg11 abcg12 exhibits ABCG12-containing membrane inclusions protruded into the vacuole and contiguous with the endoplasmic reticulum (PubMed:20870961). Reduced polarizing on the adaxial and abaxial leaves surfaces, and impaired impact of viral infection by Turnip vein clearing virus (TVCV) on the polarization of reflected light leading to high light reflections; this phenotype is not visible upon viral infection by Cucumber mosaic virus (CMV) (PubMed:28346494). Belongs to the ABC transporter superfamily. ABCG family. Eye pigment precursor importer (TC 3.A.1.204) subfamily.