Soluble amyloid beta-oligomers affect dielectric membrane properties by bilayer insertion and domain formation: implications for cell toxicity.

ABSTRACT: It is well established that Alzheimer's amyloid beta-peptides reduce the membrane barrier to ion transport. The prevailing model ascribes the resulting interference with ion homeostasis to the formation of peptide pores across the bilayer. In this work, we examine the interaction of soluble prefibrillar amyloid beta (Abeta(1-42))-oligomers with bilayer models, observing also dramatic increases in ion current at micromolar peptide concentrations. We demonstrate that the Abeta-induced ion conductances across free-standing membranes and across substrate-supported "tethered" bilayers are quantitatively similar and depend on membrane composition. However, characteristic signatures of the molecular transport mechanism were distinctly different from ion transfer through water-filled pores, as sho

SUBMITTER: Valincius G 

PROVIDER: S-EPMC2576380 | biostudies-literature | 2008 Nov

REPOSITORIES: biostudies-literature