ALS (Amyotrophic lateral sclerosis), or Lou Gehrig’s Disease, is a fatal neurodegenerative disease that involves the selective progressive death of motor neurons. The majority of ALS cases are sporadic with an unknown cause, but about 10-20% of the cases are familial ALS (fALS) which are caused by genetic mutations that appear to be inherited.
An enzyme involved in converting toxic superoxide radicals to oxygen and hydrogen peroxide, copper-zinc superoxide dismutase (SOD1), is linked to fALS, with over 100 mutations known to cause the disease. It has been thought that the SOD1 gains a toxic function, specifically aggregation of the protein, which is harmful to the cell.
We prepared two mutants of SOD1 in collaboration with Joan Valentine’s research group at UCLA. The two mutants were C111S relative to our wild type (AS), which already contains two mutations (C6A and C11S mutations), and C6S relative to the true wild type.
The two different mutations were introduced into the true and AS WT SOD1 gene using a QuikChange II Site-Directed Mutagenesis kit. Once we had confirmation of the mutations by DNA sequencing, we grew, isolated, and purified the mutant proteins as well as the true wild type and our wild type SOD1. The purification involved a phenyl sepharose column and a DEAE Sephadex column which involves hydrophobic interaction chromatography and anion exchange chromatography respectively.
Caitlin Blum, ’13
Major: Biochemistry and Molecular Biology
Christopher Rishel, ’13
Majors: Chemistry, Biochemistry and Molecular Biology
Sponsor: Cynthia Strong