The ATP-binding cassette (ABC) gene family of Plasmodium falciparum

Multidrug resistance (MDX) in mammalian tumour cells is mediated by P-glycoproteins. The apparent similarities between MDX and the chloroquine-resistance phenotype (CQR) in Plasmodium falciparum suggests that homologous proteins may be involved. In mammals, P-glycoproteins are encoded by mdr genes that are a subset of a superfamily characterized by ATP-binding cassettes (ABC). Three genes, pfmdr1, pfmdr2 and pfef3-r1, have been identified in P. falciparum that have homology to the ABC transporter gene family. Each protein encoded by these genes has a distinct structure, suggesting functional differences between the three. Justin Rubio and Alan Cowman here discuss the structure and possible function of the ABC proteins from P. falciparum and evidence that the protein encoded by the pfmdr1 gene can influence quinoline-containing antimalarial drug-resistance phenotypes.