ATP-binding cassette domain 2 of multidrug resistance-associated protein
The ABC subfamily C is also known as MRP (multidrug resistance-associated protein). Some of the MRP members have five additional transmembrane segments in their N-terminus, but the function of these additional membrane-spanning domains is not clear. The MRP was found in the multidrug-resistance lung cancer cell in which p-glycoprotein was not overexpressed. MRP exports glutathione by drug stimulation, as well as, certain substrates in conjugated forms with anions, such as glutathione, glucuronate, and sulfate.