We discovered a novel inhibitor of dopamine transport in Lobelia cardinalis.

We functionally expressed the Human dopamine transporter in L. cardinalis plant cells.

Next a Gain-of-function mutant transgenic population was generated from these cells, in presence of a neurotoxin accumulated by the transporter.

The resulting toxin-resistant population was highly enriched in mutants with increased inhibitory activity on the transporter.

Some toxin-resistant mutants overproduce the known active metabolite from wild-type.

Many others contain other active metabolites including some not readily detectable in the wild-type plant.