Topology of SERT derived from LeuT. The substrate-binding pocket is
formed by residues positioned in TM1, TM3, TM6, and TM8 (shown in
gray). Residues elucidated as critical in recognition of SSRIs and
TCAs are indicated as follows: Tyr-95
(29), Asp-98
(23), Ala-169
(31), Ile-172
(28), Met-180
(30), Ser-276
(40), Phe-513
(30), Ser-545
(41), and Phe-586
(42).