2022 Volume 57 Issue 2 Pages 123-130
Transmembrane transport of bioactive molecules is a pivotal mechanism that regulates their activities/functions in coordination with the biosynthesis and degradation (inactivation) of the compounds. NITRATE TRANSPORTER 1/PEPTIDE TRANSPORT FAMILY (NPF) proteins have been regarded for a long time as nitrate transporters involved in nitrogen acquisition and allocation in plants. However, recent genetic and biochemical studies have revealed that the family members transport various types of small compounds including plant hormones. This review summarizes the physiological functions of NPFs by mainly focusing on their roles as transporters of plant hormones and plant-specialized metabolites.