Expression pattern:Expressed in columella cells (mainly S1 and S2), in vasculature in the more mature part and in the LRP.Subcellular expression:Plasma membrane in columella and LRP, cytoplasm in vasculature.TAIR Annotation:PIN7 (PIN-FORMED 7); auxin efflux transmembrane transporter/ auxin:hydrogen symporter/ transporterEncodes a novel component of auxin efflux that is located apically in the basal cell and is involved during embryogenesis in setting up the apical-basal axis in the embryo. It is also involved in pattern specification during root development. In roots, it is expressed at lateral and basal membranes of provascular cells in the meristem and elongation zone, whereas in the columella cells it coincides with the PIN3 domain. Plasma membrane-localized PIN proteins mediate a saturable efflux of auxin. PINs mediate auxin efflux from mammalian and yeast cells without needing additional plant-specific factors. The action of PINs in auxin efflux is distinct from PGPs, rate-limiting, specific to auxins and sensitive to auxin transport inhibitors. PINs are directly involved of in catalyzing cellular auxin efflux.PIN-FORMED 7 (PIN7); FUNCTIONS IN: auxin:hydrogen symporter activity, transporter activity, auxin efflux transmembrane transporter activity; INVOLVED IN: response to cyclopentenone, root development, longitudinal axis specification, auxin polar transport, pattern specification process; LOCATED IN: plasma membrane, membrane; EXPRESSED IN: 24 plant structures; EXPRESSED DURING: 13 growth stages; CONTAINS InterPro DOMAIN/s: Auxin efflux carrier, subgroup (InterPro:IPR014024), Auxin efflux carrier (InterPro:IPR004776); BEST Arabidopsis thaliana protein match is: PIN3 (PIN-FORMED 3); auxin:hydrogen symporter/ transporter (TAIR:AT1G70940.1); Has 1079 Blast hits to 992 proteins in 269 species: Archae - 31; Bacteria - 500; Metazoa - 7; Fungi - 2; Plants - 251; Viruses - 0; Other Eukaryotes - 288 (source: NCBI BLink).