Comparison of structure and dynamics of micelle-bound human alpha-synuclein and Parkinson disease variants

J Biol Chem. 2005 Dec 30;280(52):43179-87. doi: 10.1074/jbc.M507624200. Epub 2005 Sep 15.

Abstract

Three point mutations (A30P, E46K, and A53T) as well as gene triplication genetically link the 140-residue protein alpha-synuclein (aS) to the development of Parkinson disease. Here, the structure and dynamics of micelle-bound aS(A30P) and aS(A53T) are described and compared with wild-type aS, in addition to describing the aS-micelle interaction. A53T is sensed only by directly adjacent residues and leaves the backbone structure and dynamics indistinguishable from the wild type. A30P interrupts one helix turn (Val26-Ala29) and destabilizes the preceding one. A shift in helix register following A30P disturbs the canonical succession of polar and hydrophobic residues for at least two turns. The shortened helix-N adopts a slightly higher helical content and is less bent, indicating that strain was present in the micelle-bound helix. In the vicinity of the A30P-induced perturbations, the underlying micelle environment has rearranged, but nevertheless all aS variants maintain similar interrelationships with the micelle. Moreover, aS-micelle immersion correlates well with fast and slow aS backbone dynamics, allowing a rare insight into protein-micelle interplay.

Publication types

  • Research Support, N.I.H., Intramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alanine / chemistry
  • Amino Acid Sequence
  • Humans
  • Kinetics
  • Magnetic Resonance Spectroscopy
  • Micelles*
  • Models, Molecular
  • Molecular Conformation
  • Molecular Sequence Data
  • Mutation
  • Parkinson Disease / genetics
  • Parkinson Disease / pathology*
  • Point Mutation
  • Protein Conformation
  • Protein Structure, Secondary
  • Protein Structure, Tertiary
  • Serine / chemistry
  • Sodium Dodecyl Sulfate / chemistry
  • Valine / chemistry
  • alpha-Synuclein / chemistry*

Substances

  • Micelles
  • alpha-Synuclein
  • Sodium Dodecyl Sulfate
  • Serine
  • Valine
  • Alanine