TY - JOUR
T1 - Relevance of the N-terminal NLS-like sequence of the prion protein for membrane perturbation effects
AU - Oglecka, Kamila
AU - Lundberg, Pontus
AU - Magzoub, Mazin
AU - Göran Eriksson, L. E.
AU - Langel, Ülo
AU - Gräslund, Astrid
N1 - Funding Information:
We thank Dr Jens Danielsson for valuable help with the hBRCs sampling. We also thank Mr Torbjörn Astlind for expert instrumental assistance. The study was supported by grants from the Swedish Research Council, subject areas: Natural Science and Technology; Medicine (VR-NT and VR-M), and the European Commission, contract LSHG-CT-2004-512051.
PY - 2008/1
Y1 - 2008/1
N2 - 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 23-50 (mPrPp(23-50)), respectively. In erythrocytes, mPrPp(1-28) induced ∼ 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 ∼ 12% for 50 μM mPrPp(1-28), and ∼ 1% for 50 μM 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(1-28) 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.
AB - 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 23-50 (mPrPp(23-50)), respectively. In erythrocytes, mPrPp(1-28) induced ∼ 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 ∼ 12% for 50 μM mPrPp(1-28), and ∼ 1% for 50 μM 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(1-28) 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.
KW - Calcein leakage
KW - Endosomal escape
KW - Haemoglobin leakage
KW - Membrane translocation
KW - NLS-like sequence
KW - Prion protein
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U2 - 10.1016/j.bbamem.2007.09.034
DO - 10.1016/j.bbamem.2007.09.034
M3 - Article
C2 - 17967411
AN - SCOPUS:38149114599
SN - 0005-2736
VL - 1778
SP - 206
EP - 213
JO - Biochimica et Biophysica Acta - Biomembranes
JF - Biochimica et Biophysica Acta - Biomembranes
IS - 1
ER -