ABC transporters act as gate-keepers to regulate molecule traffic going in and out of cells. Transporter proteins are located within a cell membrane and act as pumps to actively transport metabolites and compounds across a cellular membrane. The transporters we study are medically relevant as they are responsible for the development of multi-drug resistance and have been implicated in diseases such as cystic fibrosis, macular degeneration due to Stargardt’s disease and non-tension glaucoma.  Dr.