Amino acid permeases are membrane permeases involved in the transport of amino acids into the cell. A number of such proteins have been found to be evolutionary related. These proteins contain 12 transmembrane segments. Amino acid permeases are membrane permeases involved in the transport of amino acids into the cell. A number of such proteins have been found to be evolutionary related. These proteins contain 12 transmembrane segments. CIP1; SLC12A1; SLC12A2; SLC12A3; SLC12A4; SLC12A5; SLC12A6; SLC12A7; SLC12A8; SLC12A9; SLC7A1; SLC7A10; SLC7A11; SLC7A13; SLC7A14; SLC7A2; SLC7A3; SLC7A4; SLC7A5; SLC7A6; SLC7A7; SLC7A8; SLC7A9;