Interaction of full length recombinant hamster prion protein with liposomes mimicking lipid rafts or non-raft membrane regions was studied by circular dichroism, chemical cross-linking and sucrose gradient ultracentrifugation. At pH 7.0, the protein bound palmitoyloleoylphosphatidylcholine/cholesterol/sphingomyelin/monosialoganglioside GM1 (GM1) ganglioside liposomes but not palmitoyloleoylphosphatidylcholine alone (bound/free = 0.33 and 0.01, respectively), maintaining the native α-helical structure and monomeric form. At pH 5.0, though still binding to quaternary mixtures, in particular GM1, the protein bound also to palmitoyloleoylphosphatidylcholine (bound/free 0.35) becoming unfolded and oligomeric. The pH-dependent interaction with raft or non-raft membranes might have implication in vivo, by stabilizing or destabilizing the protein.
|Titolo:||Prion protein structure is affected by pH-dependent interaction with membranes : a study in a model system|
|Parole Chiave:||Circular dichroism; Lipid rafts; Liposomes; Prion protein; Protein structure|
|Settore Scientifico Disciplinare:||Settore BIO/10 - Biochimica|
|Data di pubblicazione:||2008|
|Appare nelle tipologie:||01 - Articolo su periodico|