Figure 1.

Overview of the function of amino acid transporters identified in plants. (A) Summary of transporters involved in intercellular and long-distance transport of amino acids. Some genes that were proposed to participate in certain amino acid transport steps are marked with question marks due to lack of direct evidence. (B) Summary of transporters involved in intracellular transport of amino acids. Transporters with defined transport direction are marked with black arrows. References on these genes depicted in the figure can be found in the main text.