Mamma Mia, P-glycoprotein binds again

Richard Callaghan1, Ingrid C Gelissen2, Anthony M George3

  • 1Research School of Biology, and the Medical School, Australian National University, Canberra, ACT, Australia.

FEBS Letters
|October 6, 2020
PubMed

The levels of amyloid peptides in the brain are regulated by a clearance pathway from neurons to the blood-brain barrier. The first step is thought to involve diffusion from the plasma membrane to the interstitium. However, amyloid peptides are hydrophobic and avidly intercalate within membranes. The ABC transporter P-glycoprotein is implicated in the clearance of amyloid peptides across the blood-brain, but its role at neurons is undetermined. We here propose that P-glycoprotein mediates 'exit' of amyloid peptides from neurons. Indeed, amyloid peptides have physicochemical similarities to substrates of P-glycoprotein, but their larger size represents a conundrum. This review probes the plausibility of a mechanism for amyloid peptide transport by P-glycoprotein exploiting evolving biochemical and structural models.

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