NHE8 control on pH homeostasis in RPE cells

Summer 2016

Ian Ferguson : Applied Mathematics, Molecular Cell Biology

Mentor: Xiaohua Gong

In the eye, Retinal Pigment Epithelium (RPE) cells are important in maintaining the health of photoreceptor cells. RPE defects can lead to early photoreceptor cell death which is linked to several vision disorders, including Age-Related Macular Degeneration (AMD). The Gong Laboratory has previously linked the protein NHE8, a proton/sodium ion transporter mostly localized to protein secretory pathways, to retinal degeneration that is associated with RPE and photoreceptor cell loss. It is hypothesized that NHE8 mutant proteins lose the ability to exchange protons and sodium ions in intracellular compartments or vesicles, which would disrupt pH regulation and lead to the RPE cell defects.
The goal of this project is to further investigate the role that NHE8 plays in pH homeostasis in RPE cells. I will be using primary cultures of mouse RPE cells (wild type and mutant NHE8) with a coupled fluorescent protein system sensitive to pH changes (mcherry/pHlourin) in order to track intracellular and vesicular pH regulation while passing the cells through a pH gradient. In this manner we can see how the cells without functional NHE8 proteins are able to control pH homeostasis compared to their wild type companions. A greater understanding of the process by which NHE8 affects RPE cell health may help us further understand the mechanism involved in these particular vision disorders.

I would like to thank the Pergo Foundation for supporting my summer research project. I am looking forward to the opportunity to gain more experience in research and learn more about molecular biology and vision science, and I am very excited to have the chance to design and implement an experiment from start to finish. This fellowship will help me develop skills that I will continue to use in pursuit of a career in research science.