Copper and Zinc Metallation Status of Copper Zinc Superoxide Dismutase form Amyotrophic Lateral Sclerosis Transgenic Mice

Journal Article · Fri Sep 24 04:00:00 EDT 2010 · The Journal of Biological Chemistry

OSTI ID:1019462

Lelie, H L; Miller, L; Liba, A; Bourassa, M W; Chattopadhyay, M; Chan, P K; Gralla, E B; Borchelt, D R

Mutations in the metalloenzyme copper-zinc superoxide dismutase (SOD1) cause one form of familial amyotrophic lateral sclerosis (ALS), and metals are suspected to play a pivotal role in ALS pathology. To learn more about metals in ALS, we determined the metallation states of human wild-type or mutant (G37R, G93A, and H46R/H48Q) SOD1 proteins from SOD1-ALS transgenic mice spinal cords. SOD1 was gently extracted from spinal cord and separated into insoluble (aggregated) and soluble (supernatant) fractions, and then metallation states were determined by HPLC inductively coupled plasma MS. Insoluble SOD1-rich fractions were not enriched in copper and zinc. However, the soluble mutant and WT SOD1s were highly metallated except for the metal-binding-region mutant H46R/H48Q, which did not bind any copper. Due to the stability conferred by high metallation of G37R and G93A, it is unlikely that these soluble SOD1s are prone to aggregation in vivo, supporting the hypothesis that immature nascent SOD1 is the substrate for aggregation. We also investigated the effect of SOD1 overexpression and disease on metal homeostasis in spinal cord cross-sections of SOD1-ALS mice using synchrotron-based x-ray fluorescence microscopy. In each mouse genotype, except for the H46R/H48Q mouse, we found a redistribution of copper between gray and white matters correlated to areas of high SOD1. Interestingly, a disease-specific increase of zinc was observed in the white matter for all mutant SOD1 mice. Together these data provide a picture of copper and zinc in the cell as well as highlight the importance of these metals in understanding SOD1-ALS pathology.

• Research Organization: Brookhaven National Laboratory (BNL) National Synchrotron Light Source
• Sponsoring Organization: DOE - OFFICE OF SCIENCE
• DOE Contract Number: AC02-98CH10886
• OSTI ID: 1019462
• Report Number(s): BNL--94908-2011-JA; KC0401030
• Journal Information: The Journal of Biological Chemistry, Journal Name: The Journal of Biological Chemistry Journal Issue: 4 Vol. 286
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
60 APPLIED LIFE SCIENCES
COPPER
CROSS SECTIONS
DISEASES
FLUORESCENCE
GENOTYPE
HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY
HOMEOSTASIS
HYPOTHESIS
IN VIVO
MICE
MICROSCOPY
MUTANTS
MUTATIONS
PATHOLOGY
PROTEINS
SPINAL CORD
STABILITY
SUBSTRATES
SUPEROXIDE DISMUTASE
TRANSGENIC MICE
ZINC
national synchrotron light source