Figure 2.

Disease-associated nsSNPs at a putative communication network between the NBD and the transmembrane helices of human ABC transporters. Mutations in the ARA motif, which forms a small, partially buried α-helix that may interact with the transmembrane helices, are associated with disease in seven human ABC transporters (Table I). A surface representation of the human ABCC NBD2 model structure is shown with the ARA motif colored in red, the mobile Q-loop in purple, and the TMD of the structure of the Staphylococcus aureus multidrug ABC transporter Sav1866 in light blue. The transmembrane segment that appears to interact with the Q-loop/ARA region is a portion of the L2 loop.²