Relevance of the N-terminal NLS-like sequence of the prion protein for membrane perturbation effects
2008 (English)In: Biochimica et Biophysica Acta, ISSN 0006-3002, Vol. 1778, no 1, 206-213 p.Article in journal (Refereed) Published
We investigated the nuclear localization-like sequence KKRPKP, corresponding to the residues 23-28 in the mouse prion protein (mPrP), for its membrane perturbation activity, by comparing effects of two mPrP-derived peptides, corresponding to residues 1-28 (mPrPp(1-28)) and 2350 (rnPrPp(23-50)), respectively. In erythrocytes, mPrPp(1-28) induced similar to 60% haemoglobin leakage after 30 min, whereas mprPp(23-50) had negligible effects. In calcein-entrapping, large unilamellar vesicles (LUVs), similar results were obtained. Cytotoxicity estimated by lactate dehydrogenase leakage from HeLa cells, was found to be similar to 12% for 50 mu M mPrPp(1-28), and similar to 1% for 50 mu M mPrPp(23-50). Circular dichroism spectra showed structure induction of mPrPp(1-28) in the presence of POPC:POPG (4:1) and POPC LUVs, while mprPp(23-50) remained a random coil. Membrane translocation studies on live HeLa cells showed mPrPp(I-28) co-localizing with dextran, suggesting fluid-phase endocytosis, whereas mPrPp(23-50) hardly translocated at all. We conclude that the KKRPKP-sequence is not sufficient to cause membrane perturbation or translocation but needs a hydrophobic counterpart.
Place, publisher, year, edition, pages
2008. Vol. 1778, no 1, 206-213 p.
prion protein, membrane translocation, calcein leakage, endosomal escape, NLS-like sequence, haemoglobin leakage
Biochemistry and Molecular Biology
IdentifiersURN: urn:nbn:se:su:diva-20657DOI: 10.1016/j.bbamem.2007.09.034ISI: 000253269500022PubMedID: 17967411OAI: oai:DiVA.org:su-20657DiVA: diva2:187183