Spectroscopic and Electronic Structure Studies of Copper(II) Binding to His111 in the Human Prion Protein Fragment 106−115: Evaluating the Role of Protons and Methionine Residues

Although a number of features distinguish the disease isoform of the prion protein (PrPSc) from its normal cellular counterpart (PrPC) in the transmissible spongiform encephalopathies (TSEs), the neuropathogenesis of these diseases remains an enigma. The amyloid fibrils formed by fragments of human PrP have, however, been shown to be directly neurotoxic in vitro. We show here that sulphated polysaccharides (heparin, keratan and chondroitin) inhibit the neurotoxicity of these amyloid fibrils and this appears to be mediated via inhibition of the polymerization of the PrP peptide into fibrils. This provides a rationale for the therapeutic effects of sulphated polysaccharides and suggests a rapid in vitro functional screen for TSE therapeutics.

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Crystal Structure of a Human Prion Protein Fragment Reveals a Motif for Oligomer Formation

Journal of the American Chemical Society ◽

10.1021/ja403001q ◽

2013 ◽

Vol 135 (28) ◽

pp. 10202-10205 ◽

Cited By ~ 44

Author(s):

Marcin I. Apostol ◽

Kay Perry ◽

Witold K. Surewicz

Keyword(s):

Crystal Structure ◽

Prion Protein ◽

Protein Fragment ◽

Oligomer Formation ◽

Human Prion Protein

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Characterization of the Proapoptotic Intracellular Mechanisms Induced by a Toxic Conformer of the Recombinant Human Prion Protein Fragment 90-231

Annals of the New York Academy of Sciences ◽

10.1196/annals.1378.030 ◽

2006 ◽

Vol 1090 (1) ◽

pp. 276-291 ◽

Cited By ~ 14

Author(s):

V. VILLA ◽

A. CORSARO ◽

S. THELLUNG ◽

D. PALUDI ◽

K. CHIOVITTI ◽

...

Keyword(s):

Prion Protein ◽

Protein Fragment ◽

Human Prion Protein ◽

Intracellular Mechanisms

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Both lysine-clusters of the NH2-terminal prion-protein fragment PrP23-110 are essential for t-PA mediated plasminogen activation

Thrombosis and Haemostasis ◽

10.1160/th03-06-0382 ◽

2004 ◽

Vol 91 (03) ◽

pp. 465-472 ◽

Cited By ~ 16

Author(s):

Guido Epple ◽

Kristina Langfeld ◽

Michael Baier ◽

Hermann-Georg Holzhütter ◽

Eckart Köttgen ◽

...

Keyword(s):

Prion Protein ◽

Plasmon Resonance ◽

Cellular Prion Protein ◽

Plasminogen Activation ◽

Protein Fragment ◽

Chip Surface ◽

Mutant Proteins ◽

Lysine Residues ◽

Binding Curves

SummaryWe have recently shown that the NH2-terminal fragment (PrP23-110) of the human cellular prion protein (PrPc) stimulates t-PA mediated plasminogen activation. PrP23-110 contains an N-terminal lysine cluster (LC1; K23, K24, K27) and a C-terminal one (LC2; K101, K104, K106, K110). To study their biological function we have substituted all lysine residues of each cluster by alanine and generated the recombinant PrP proteins PrP23110sLC1 and PrP23-110sLC2. The ability of the mutant proteins to stimulate plasminogen activation was assayed. We found that both lysine clusters are essential for t-PA mediated plasminogen activation. We further studied the binding of soluble PrP23110 to immobilized t-PA or plasminogen using surface plasmon resonance. The recorded binding curves could not be modeled by classical 1:1 binding kinetics suggesting oligomerisation of PrP23-110. Further plasmon resonance studies show that indeed PrP23-110 binds to itself and that glycosaminoglycans modify this interaction. Binding of t-PA or plasminogen to PrP23-110 was no longer influenced by glycosaminoglycans when PrP23-110 was immobilized on the chip surface. Thus a possible role of heparin as a cofactor in the stimulation of plasminogen activation by t-PA could be the generation of a PrP23-110 form with both lysine clusters accessible for binding of t-PA and plasminogen.

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