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Anything in this section will appear adjacent to the 3D structure and will be scrollable.
Anything in this section will appear adjacent to the 3D structure and will be scrollable.
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The following residue alterations confer increased susceptibility to the unfolding of alpha helices characteristic of spongiform encephalopathies.
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Residue 129 Val-->Met. As of January 2010, only individuals with homozygous Met129 had been diagnosed with infectious Creutzfeldt–Jakob disease.<ref name="Lee">PMID:19927125</ref>
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Residue 170 Ser-->Asn. <ref name="Calzolai">PMID:10900000</ref>
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</StructureSection>
</StructureSection>

Revision as of 05:20, 27 November 2012

Contents

Prions as a disease causing agent

Human Prion Protein in dimer form 1i4m
Human Prion Protein in dimer form 1i4m


Image:Http://www.proteopedia.org/wiki/index.php/Image:10131 lores.jpg
Caption: Holes in this sponge like brain tissue result from pockets of prion aggregation [1]

Prions are infectious or genetic misfolded proteins which act as templates upon which properly folded prion protein monomers can aggregate. Prions contain no nucleic acid such as other infectoius molecules or organisms. Human Prion Protein or Major Prion protein, exists as a normal constituent of human cells, found mostly in the brain[2] and is called PrPC.[3] PrPC is composed of mostly helix whereas the infectious form, PrPSc, is composed of high percentage beta sheets.[3]

The diseases prions confer are neurodegenerative disorders which result from the large scale aggregation of these proteins. For more information about the infections related to prions see Transmissible spongiform encephalopathy at Wikipedia.


Unfolding Mechanism

Currently, the mechanism by which a template prion unfolds a the helices of a properly folded prion protein is unknown. Specific residues have been shown to either confer resistance or lend themselves to this unfolding.

PrPC natural monomer

Major Prion Protein 1QLX

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=== PrPSc

Amyloid formation: Human Prion Protein 2RNM

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Dimer Form

Major Prion Protein: Dimerized 1I4M

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Reference List

  1. Image of Creutzfeldt-Jakob positive brain tissue was obtained from The CDC's Public Health Image Library.
  2. Centers for Disease Control and Prevention
  3. 3.0 3.1 Prusiner SB. Prions. Proc Natl Acad Sci U S A. 1998 Nov 10;95(23):13363-83. PMID:9811807
  4. Lee S, Antony L, Hartmann R, Knaus KJ, Surewicz K, Surewicz WK, Yee VC. Conformational diversity in prion protein variants influences intermolecular beta-sheet formation. EMBO J. 2010 Jan 6;29(1):251-62. Epub 2009 Nov 19. PMID:19927125 doi:10.1038/emboj.2009.333
  5. Calzolai L, Lysek DA, Guntert P, von Schroetter C, Riek R, Zahn R, Wuthrich K. NMR structures of three single-residue variants of the human prion protein. Proc Natl Acad Sci U S A. 2000 Jul 18;97(15):8340-5. PMID:10900000

Proteopedia Page Contributors and Editors (what is this?)

Erin May, Jaime Prilusky

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