Physics – Biological Physics
Scientific paper
2003-07-29
Physics
Biological Physics
14 pages; 8 figures; 2nd revision
Scientific paper
10.1529/biophysj.103.032342
Inspired by recent suggestions that the Alzheimer's amyloid beta peptide (A beta) can insert into cell membranes and form harmful ion channels, we model insertion of the 40 and 42 residue forms of the peptide into cell membranes using a Monte Carlo code which is specific at the amino acid level. We examine insertion of the regular A-beta peptide as well as mutants causing familial Alzheimer's disease, and find that all but one of the mutants change the insertion behavior by causing the peptide to spend more simulation steps in only one leaflet of the bilayer. We also find that A-beta 42, because of the extra hydrophobic residues relative to A-beta 40, is more likely to adopt this conformation than A-beta 40 in both wild-type and mutant forms. We argue qualitatively why these effects happen. Here, we present our results and develop the hypothesis that this partial insertion increases the probability of harmful channel formation. This hypothesis can partly explain why these mutations are neurotoxic simply due to peptide insertion behavior. We further apply this model to various artificial A-beta mutants which have been examined experimentally, and offer testable experimental predictions contrasting the roles of aggregation and insertion with regard to toxicity of A-beta mutants. These can be used through further experiments to test our hypothesis.
Cox Daniel L.
Longo Marjorie L.
Maddox Michael W.
Mobley David L.
Singh Rajiv R. P.
No associations
LandOfFree
Modeling Amyloid Beta Peptide Insertion into Lipid Bilayers does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Modeling Amyloid Beta Peptide Insertion into Lipid Bilayers, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Modeling Amyloid Beta Peptide Insertion into Lipid Bilayers will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-663208