Low-affinity proton-dependent nitrate transporter. Not involved in dipeptides transport. Involved in delivering nitrate for seed development. Expressed in flowers and siliques. Expressed in vascular bundle of the siliques and in funiculus. Expression increases after pollination. Up-regulated by nitrogen starvation. Aberrant embryo development and increased seed abortion. Reduced seed nitrate content. Belongs to the major facilitator superfamily. Proton-dependent oligopeptide transporter (POT/PTR) (TC 2.A.17) family.