CRISPR/Cas9-mediated functional screening of proton pumps during development of the Xenopus mucociliary epidermis

Summer 2016

Dingyuan I. Sun : Molecular and Cell Biology

Mentor: Richard Harland

Inhibition or mutation of transmembrane proton pumps is associated with human airway diseases, such as pneumonia and cystic fibrosis. However, the underlying molecular mechaisms remain poorly understood. A mucociliary epithelium lines the upper repiratory tract and clears the airways from inhaled pathogens. Inhibition of the proton pump gastric H+/K+ATPAse (ATP4a) causes defects in the mucociliary development through impaired canonical Wnt/Ī²-catenin signaling. Furthermore, other proton pumps were implicated in Wnt signaling regulation.I propose that proton pumps in general influence Wnt pathway activation and development of mucociliary epithelia. In my project, I will conduct a functional screen by knockout of different proton pumps using CRISPR/Cas9. Effects on the mucociliary epidermis will be analyzed by in situ hybridization and immunofluorescent microscopy. The frog (Xenopus lavis) embryos are used as a model to study vertebrate mucociliary epithelia because they possess a mucociliary epidermis and a fast development. My research will provide more understanding of the molecular mechanism of proton pumps, cell signaling and human airway diseases.

I am grateful for the generous support of the Pergo foundation for giving me this opportunity to focus on research this summer. I have been working in the Harland lab for 3 years and it has been one of the most rewarding and educational experiences in my undergraduate education. As a Cal student, I found that it is hard to balance research with a part time job and other extracurricular activities while having a fulltime course load. I am excited to conduct my project this summer with the support of the Pergo foundation.