Fig. 3: Comparative structural analysis across diverse conformational states.

a Superposition of TauT^Apo (yellow), TauT^GABA (pink) and TauT^Tau (cyan). The TM regions remain nearly identical, except that TM1a displays variation. b Structural superposition of binding sites in TauT^Tau and TauT^GABA. Taurine and GABA are shown as ball sticks and critical residues are represented as sticks. c-d Detailed changes of TM1. Taurine and GABA are displayed as ball sticks. Residues that undergo significant displacement are displayed as sticks. e Comparison of the Na1 and Na2 sites in TauT^Apo and TauT^Tau. f Detailed view of the N-terminus of TauT^Tau. The electron density is depicted as a gray mesh and contoured at 5 σ by ChimeraX. Residues within the N-terminus are visualized as sticks. g The interactions of N-terminus in TauT^Tau. Key residues are labeled and represented by sticks. h Extracellular gate in TauT. Arg66 and Phe300 are key residues in the extracellular gate. Arg66 forms a cation-π interaction with Phe300, as indicated by the black dashed line. Arg66 is also coordinated by Gly62, Asp459 and Ser464. Hydrogen bonds are shown.