Molecular basis for differential glycine transporters sensitivity to sanguinarine.
We previously demonstrated that glycine transporters GlyT1 and GlyT2 are differentially affected by toxic benzophenanthridine alkaloids. Using a combination of homology modeling, knowledge of the sensitivity of sanguinarine to sulfhydryl reagents and site directed mutagenesis we show here that the increased sensitivity of human GlyT1c to sanguinarine is abolished by the mutation of only cysteine 475. Inhibition requires the membrane permeable alkaloid alkanolamine, which is consistent with the intracellular location of the targeted cysteine.
Laboratory of Neurobiology, Institute of Molecular Biology, Slovak Academy of Sciences, Dubravska cesta 21, 842 51 Bratislava, Slovakia. Frantisek.Jursky@savba.sk
Frantisek
F
Jursky
Martina
M
Baliova
Andrea
A
Mihalikova
D000890:Anti-Infective Agents / Q000633:toxicity*; D053119:Benzophenanthridines / Q000633:toxicity*; D002463:Cell Membrane Permeability; D003545:Cysteine / Q000737:chemistry / Q000235:genetics; D050487:Glycine Plasma Membrane Transport Proteins / Q000737:chemistry / Q000187:drug effects* / Q000378:metabolism; D057809:HEK293 Cells; D006801:Humans; D007546:Isoquinolines / Q000633:toxicity*; D016297:Mutagenesis, Site-Directed; D009154:Mutation; D017434:Protein Structure, Tertiary
D000890:Anti-Infective Agents; D053119:Benzophenanthridines; D050487:Glycine Plasma Membrane Transport Proteins; D007546:Isoquinolines; C493271:SLC6A5 protein, human; C493268:SLC6A9 protein, human; C005705:sanguinarine; D003545:Cysteine