Table 1.

Comparison between the experimental observations/insights and insights from our simulated 3D model of the DAT-DA-cocaine complex.

Experiments	Observations or insights from the experiment	Ref.	Insights from our DAT-DA-COC model
Hg2+ binding test	Binding of cocaine was inhibited.	9, 10	Cocaine-binding site is near the extracellular side of TM domain of DAT.
Epitope-specific immunoprecipitation studies	Cocaine binding site should be near helix 6 of DAT	35	Cocaine-binding site is formed by α-helices 1, 3, 6, and 8 of DAT
Trp84Leu mutation	Cocaine-binding affinity was increased (~8-fold decrease for the apparent dissociation constant).	28, 39	The mutation provides more space to accommodate the cationic head of cocaine at the binding site.
Phe154Ala and Phe155Ala mutations	Cocaine-binding affinity was decreased.	26	The mutation weakens the packing between the two residues and the benzoyl ester group of cocaine.
Phe391Ala mutation	Cocaine-binding affinity was decreased by ~6-fold.	26	The mutation weakens packing between the residue and the cationic head of cocaine.
Asp313Asn and Asp313Gln mutations	Cocaine-binding affinity was increased (~3-fold decrease for the apparent dissociation constant).	28, 39	Arg85-Asp476 salt bridge matches better around cationic head of cocaine after the mutation.
Leu104Val/Phe105C ys/Ala109Val mutation	The mutant was ~70-fold insensitive to cocaine inhibition compared to the wild-type DAT.	4, 29	Hydrophobic interactions with Phe105 is destroyed and α-helix 6 stays away from the cocaine-binding site in the mutant.
Asp79Glu mutation	The mutation considerably decreased DAT binding with dopamine, but with little change in DAT-cocaine binding.	30	The negatively charged side chain of the residue has direct contact with the cationic head of dopamine, but has not direct contact with that of cocaine.