Open AccessProposed three-dimensional structure for the cellular prion protein.
Author(s) -
Ziwei Huang,
Jean-Marc Gabriel,
Michael A. Baldwin,
Robert J. Fletterick,
Stanley B. Prusiner,
Fred E. Cohen
Publication year - 1994
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.91.15.7139
Subject(s) - protein tertiary structure , circular dichroism , point mutation , protein secondary structure , amino acid , protein structure , helix (gastropod) , prion protein , helix bundle , mutation , biology , computational biology , protein folding , chemistry , gene , biophysics , genetics , crystallography , biochemistry , medicine , ecology , disease , pathology , snail
Prion diseases are a group of neurodegenerative disorders in humans and animals that seem to result from a conformational change in the prion protein (PrP). Utilizing data obtained by circular dichroism and infrared spectroscopy, computational studies predicted the three-dimensional structure of the cellular form of PrP (PrPc). A heuristic approach consisting of the prediction of secondary structures and of an evaluation of the packing of secondary elements was used to search for plausible tertiary structures. After a series of experimental and theoretical constraints were applied, four structural models of four-helix bundles emerged. A group of amino acids within the four predicted helices were identified as important for tertiary interactions between helices. These amino acids could be essential for maintaining a stable tertiary structure of PrPc. Among four plausible structural models for PrPc, the X-bundle model seemed to correlate best with 5 of 11 known point mutations that segregate with the inherited prion diseases. These 5 mutations cluster around a central hydrophobic core in the X-bundle structure. Furthermore, these mutations occur at or near those amino acids which are predicted to be important for helix-helix interactions. The three-dimensional structure of PrPc proposed here may not only provide a basis for rationalizing mutations of the PrP gene in the inherited prion diseases but also guide design of genetically engineered PrP molecules for further experimental studies.