A salt bridge in intracellular loop 2 is essential for folding of human p-glycoprotein.
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ABSTRACT:
SUBMITTER: Loo TW
PROVIDER: S-EPMC3656768 | biostudies-literature | 2013 May
REPOSITORIES: biostudies-literature
Publications
A salt bridge in intracellular loop 2 is essential for folding of human p-glycoprotein.
Loo Tip W TW Clarke David M DM
Biochemistry 20130503 19
There is no high-resolution structure of the human P-glycoprotein (P-gp, ABCB1) drug pump. Homology models based on the crystal structures of mouse and Caenorhabditis elegans P-gps show extensive contacts between intracellular loop 2 (ICL2, in the first transmembrane domain) and the second nucleotide-binding domain. Human P-gp modeled on these P-gp structures yields different ICL2 structures. Only the model based on the C. elegans P-gp structure predicts the presence of a salt bridge. We show th ...[more]
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