MDR1 — Arabidopsis thaliana

Summary

AT3G28860, also known as MDR1, ABCB19, or PGP19, encodes an ATP-binding cassette (ABC) transporter with auxin efflux transmembrane transporter activity, calmodulin binding, and ATP hydrolase activity. This protein localizes to the plasma membrane, particularly at basal and apical cell poles, as well as to plasmodesmata and the cytosol. MDR1 is associated with auxin transport pathways, including acropetal and basipetal auxin transport, and is linked to gravitropism, phototropism, and tropism responses. The gene has been connected to numerous developmental traits such as leaf shaping, cotyledon morphogenesis, root system development, pistil size, stamen number, and biomass yield. It is also associated with brassinosteroid signaling and response, apical hook opening, hypocotyl elongation, and shade response. Related genes in other species are linked to flower formation.