Triose phosphate/phosphate translocator that transports inorganic phosphate, 3-phosphoglycerate (3-PGA) and triose phosphate. Functions in the export of photoassimilates from chloroplasts during the day. In the light, triose phosphates are exported from the chloroplast stroma in counter exchange with inorganic phosphate (Pi), generated during sucrose biosynthesis in the cytosol. Involved in photosynthetic acclimation, a light response resulting in increased tolerance to high-intensity light. A number of isoforms are produced. According to EST sequences. Expressed in shoots, leaves and flowers. Expressed with a circadian rhythm showing an increase during the day and a decrease at night under long day conditions. No visible phenotype under normal growth condition, but strong reduction of triose phosphate export from the chloroplast and reduced photosynthetic acclimation. Belongs to the TPT transporter family. TPT (TC 2.A.7.9) subfamily.