Ligand binding and aggregation of pathogenic SOD1

Nat Commun. 2013:4:1758. doi: 10.1038/ncomms2750.

Abstract

Mutations in the gene encoding Cu/Zn superoxide dismutase-1 cause amyotrophic lateral sclerosis. Superoxide dismutase-1 mutations decrease protein stability and promote aggregation. The mutant monomer is thought to be an intermediate in the pathway from the superoxide dismutase-1 dimer to aggregate. Here we find that the monomeric copper-apo, zinc-holo protein is structurally perturbed and the apo-protein aggregates without reattainment of the monomer-dimer equilibrium. Intervention to stabilize the superoxide dismutase-1 dimer and inhibit aggregation is regarded as a potential therapeutic strategy. We describe protein-ligand interactions for two compounds, Isoproterenol and 5-fluorouridine, highlighted as superoxide dismutase-1 stabilizers. We find both compounds interact with superoxide dismutase-1 at a key region identified at the core of the superoxide dismutase-1 fibrillar aggregates, β-barrel loop II-strand 3, rather than the proposed dimer interface site. This illustrates the need for direct structural observations when developing compounds for protein-targeted therapeutics.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Apoproteins / chemistry
  • Dopamine / chemistry
  • Dopamine / metabolism
  • Enzyme Stability / drug effects
  • Epinephrine / chemistry
  • Epinephrine / metabolism
  • Guanidine / pharmacology
  • Humans
  • Isoproterenol / pharmacology
  • Ligands
  • Models, Molecular
  • Mutant Proteins / chemistry
  • Mutant Proteins / metabolism
  • Mutation / genetics*
  • Protein Binding / drug effects
  • Protein Multimerization / drug effects
  • Protein Structure, Quaternary
  • Protein Unfolding / drug effects
  • Recombinant Proteins / chemistry
  • Scattering, Small Angle
  • Superoxide Dismutase / chemistry*
  • Superoxide Dismutase / genetics*
  • Superoxide Dismutase / metabolism
  • Superoxide Dismutase-1
  • Uridine / analogs & derivatives
  • Uridine / pharmacology
  • X-Ray Diffraction

Substances

  • Apoproteins
  • Ligands
  • Mutant Proteins
  • Recombinant Proteins
  • SOD1 protein, human
  • 5-fluorouridine
  • Superoxide Dismutase
  • Superoxide Dismutase-1
  • Guanidine
  • Isoproterenol
  • Dopamine
  • Uridine
  • Epinephrine

Associated data

  • PDB/4A7S
  • PDB/4A7T
  • PDB/4A7U
  • PDB/4A7V