posted on 2018-08-22, 00:00authored byFederica Scollo, Carmelo Tempra, Fabio Lolicato, Michele F. M. Sciacca, Antonio Raudino, Danilo Milardi, Carmelo La Rosa
Amyloidogenic
proteins are involved in many diseases, including
Alzheimer’s, Parkinson’s, and type II diabetes. These
proteins are thought to be toxic for cells because of their abnormal
interaction with the cell membrane. Simpler model membranes (LUVs)
have been used to study the early steps of membrane-protein interactions
and their subsequent evolution. Phospholipid LUVs formed in water
solution establish a chemical equilibrium between self-assembled LUVs
and a small amount of phospholipids in water solution (CMC). Here,
using both experimental and molecular dynamics simulations approach
we demonstrate that the insertion of IAPP, an amyloidogenic peptide
involved in diabetes, in membranes is driven by free lipids in solution
in dynamic equilibrium with the self-assembled lipids of the bilayer.
It is suggested that this could be a general mechanism lying at the
root of membrane insertion processes of self-assembling peptides.