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Dynamics and Cleavability at the alpha-cleavage site of APP(684-726) in different lipid environments.

ABSTRACT: The occurrence of late-onset Alzheimer's disease has been related to the lipid homeostasis. We tested whether the membrane lipid environment affects the dynamics and cleavability of a model peptide corresponding to the amino acid sequence 684-726 of the amyloid precursor protein APP reconstituted in liposomes. Solid-state NMR with (2)H-Ala(713), which is located within the putative transmembrane domain, suggested that the peptide observes less rotational motion in egg phosphatidylcholine (PhC) membranes than in dimyristoyl-phosphatidylcholine (DMPC) bilayers above the main phase transition temperature T(c). The residue (15)N-Ala(692), which is in the vicinity of the alpha-cleavage site, i.e., Lys(687), showed less motion after reconstitution in distearoyl-phosphatidylcholine liposomes

SUBMITTER: Marenchino M

PROVIDER: S-EPMC2479613 | biostudies-literature | 2008 Aug

REPOSITORIES: biostudies-literature

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Dynamics and Cleavability at the alpha-cleavage site of APP(684-726) in different lipid environments.

Marenchino Marco M Williamson Philip T F PT Murri Samuel S Zandomeneghi Giorgia G Wunderli-Allenspach Heidi H Meier Beat H BH Krämer Stefanie D SD

Biophysical journal 20080404 3

The occurrence of late-onset Alzheimer's disease has been related to the lipid homeostasis. We tested whether the membrane lipid environment affects the dynamics and cleavability of a model peptide corresponding to the amino acid sequence 684-726 of the amyloid precursor protein APP reconstituted in liposomes. Solid-state NMR with (2)H-Ala(713), which is located within the putative transmembrane domain, suggested that the peptide observes less rotational motion in egg phosphatidylcholine (PhC) m ...[more]

PMID: 18390599

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