Title: Molecular Mechanism of P-glycoprotein Assembly into Cellular Membranes
Volume: 3
Issue: 5
Author(s): Victoria Anthony and William R. Skach
Affiliation:
Keywords:
P-glycoprotein, Cellular Membranes, TOPOLOGY, BIOGENESIS
Abstract: In the past decade major advances have been made towards understanding the mechanisms by which polytopic membrane proteins fold and assemble in cellular membranes. In eukaryotes, this process is mediated by a complex set of machinery in the endoplasmic reticulum (ER) that facilitates translocation of peptide loops across and integration of hydrophobic helices into the lipid bilayer. Studies evaluating the biogenesis of P-glycoprotein (P-gp) have been at the forefront of this rapidly expanding field. They have revealed a fascinating although sometimes confusing picture that has challenged our notions about general mechanisms of polytopic protein assembly and questioned specific predictions about the details and uniqueness of P-gp transmembrane topology. This review will attempt to summarize and consolidate our current knowledge of the sequence of events that gives rise to P-gp topology in the ER compartment and the implications of these events for polytopic protein biogenesis and function.