Inhibition of TORC1 Pathway in Saccharomyces Cerevisiae to Induce Autophagy Using Graphene Oxide

Abstract

Alzheimer’s Disease (AD) is a neurodegenerative brain disorder that affects close to six million people in the US alone. The disease is characterized by amyloid beta plaque buildup in the brain which limits proper communication and connection between neurons. Patients with AD were shown to have lower rates of autophagy in neuronal cells. Autophagy is the cellular process by which waste buildup is broken down through lysosomal activity. In mammals, the activated mTORC1 pathway inhibits autophagy in the presence of growth factors and amino acids. To explore the potential of using autophagic activity to break down amyloid beta plaques, Saccharomyces Cerevisiae, which conserves mTORC1 as TORC1, could be used as a model organism. This project focuses on the inhibitory effectiveness of Graphene Oxide (GO) on the TORC1 pathway in S. cerevisiae. Firstly, the cytotoxicity of GO to the S. cerevisiae species was tested to ensure GO did not hamper cell proliferation by growing S. cerevisiae in a medium which included various concentrations of GO. Then, a fluorescent marker, Rosella, which indicates autophagic activity was used to measure the effects of GO. The S. cerevisiae was transformed with the Rosella plasmid to give it fluorescent properties, following which the S. cerevisiae was grown in the presence of various GO concentrations. The resultant emissions revealed the relationship between the concentration of GO and the induction of autophagy through inhibition of the TORC1 pathway. By inducing autophagy, GO could prove to be the key to breaking down amyloid beta plaques and treating AD.