Superoxide Dismutase and Amyotrophic Lateral Sclerosis Dan Zollinger PI: Dr. Joe Beckman
Download
Report
Transcript Superoxide Dismutase and Amyotrophic Lateral Sclerosis Dan Zollinger PI: Dr. Joe Beckman
Superoxide Dismutase and
Amyotrophic Lateral Sclerosis
Dan Zollinger
PI: Dr. Joe Beckman
Linus Pauling Institute
Oxidative Stress and Familial
ALS
Motor Neuron Death
– Progressive Neurodegeneration
– Muscle Wasting
– Paralysis
– Death
Mutations to CuZn Superoxide Dismutase (SOD)
CuZn Superoxide Dismutase
Cu2+ + O2-
O2 + Cu1+
G85R and ALS
Does G85R bind copper and show
superoxide scavenging activity?
Can copper play a role in the disease?
G85R SOD Activity
900 ng
600 ng 300 ng
Bruijn, Et. al., Neuron 1997
Nitro Blue Formazan
Mass Spec Data:
Recombinant G85R SOD
2.00E + 04
CuZn
1.80E + 04
16027
1.60E + 04
Metal def.
15964
1.40E + 04
C679H1081N203O224S4CuZn
1.20E + 04
1.00E + 04
8.00E + 03
6.00E + 03
4.00E + 03
Apo
15904
2.00E + 03
0.00E + 00
15800
15850
15900
15950
16000
16050
16100
16150
16200
G85R SOD Crystal Structure
Hart, J. Biol. Chem, 2008
G85R in vivo
Identify metal status of SOD in diseased
transgenic mice
– Focus on motor neurons in ventral horn of
spinal cord
Tissue Samples for
MS SOD Assay
Dorsal
Ventral
®
ZipTip Method
Western Results of Mouse
Spinal Cord
S
P
S
P
Non transgenic mouse tissue
G85R mouse tissue
Recombinant G85R (300 ng)
5 punches (~250 g/punch) suspended in 25 L of
50mM Ammonium Acetate pH 5.1
G85R Mouse Tissue
Apo G85R
Apo G85R
Metal def. G85R
Mouse
SOD
Metal def.
G85R
Toxicity of G85R SOD
Why is G85R more toxic than other fALS
linked mutants?
Hypothesis:
– G85R SOD as a lower affinity for zinc than
other ALS mutants.
Method
– Test the metal release of the mutant using metal
chelators and compare to other mutants
Acknowledgements
Joe Beckman
Keith Nylin
Nathan Lopez
Tim Rhoads
Kevin Ahern
Howard Hughes Medical Institute
Biochemistry and Biophysics Department