My name is Katherine Heatzig and I am a junior at Pine Crest School. I conducted this research at the Scripps Research Institute in Jupiter, Florida.

The Connection Between Rhes And Mitochondria In Huntington’s Disease Affected Models

Huntington’s Disease is an autosomal dominant, neurodegenerative disease that affects 6 out of 100,000 people that causes dementia, a decline in cognitive ability, and choreiform movements and it is caused by extended CAG nucleotide repeats on the Huntingtin gene. The expanded polyglutamine chain (which contains more than the normal number of CAG nucleotide chains) alters the way the protein is folded, thus altering the function of the protein. The mutated Huntingtin gene (mHtt) that has the abnormally high number of repeats is expressed throughout the body, is known to only significantly harm the neurons in the nervous system (3). Ras Homolog Enriched in The Striatum (Rhes) is a protein that regulates the cell metabolism, binds to the AKT pathway which creates energy, and controls the synthesis of proteins (1). The mitochondria performs many critical functions within the body’s cells, for example, apoptosis, metabolism regulation, amino acid biosynthesis, and calcium homeostasis (2). When the mitochondria distribution starts declining, these functions decrease, resulting in cell damage. I harvested, transfected, and split cells that have 111 CAG repeats (Q111 Cells) and cells that have 7 CAG repeats (Q7 Cells). Then I ran Western Blots to probe for the mitochondria and the Rhes to determine if there is a significant alteration in the mitochondria shape when Q7 and Q111 cells when exposed to Rhes. I hypothesized that in Q111 cells, the mitochondria will be much less efficient when exposed to Rhes, suggesting that Rhes has malicious affects in HD patients, thus creating the symptoms. By completing my research, I have identified that the impaired mitochondrial function caused by Rhes is a contributing factor on why the Huntington’s Disease defect in motor symptoms are so severe.