Can a simple and generalizable assay distinguish between mutant phenotypes of model membrane proteins?

Abstract

Membrane proteins participate in a variety of functions including homeostasis, sensing extracellular signals, and cell recognition. Whether membrane proteins can play their role in physiology can be dictated by their ability to fold and traffic. Folding and trafficking can be regulated by a variety of factors including mutations, regulation by other genes, and the cellular environment which in dysfunction may lead to disease. The lab wants to explore how genetic and chemical perturbations alter membrane protein surface expression. A simple and generalizable fluorescence assay for distinguishing variant phenotypes will be conducted on the model membrane proteins CFTR, RHO, and CT1. The assay will then be conducted on membrane proteins with mutations known to affect folding and trafficking. Preliminary data suggest the assay can differentiate between three known phenotypes: misfolding, folding but mistrafficks, and folding and trafficks. In the future, the assay can be applied to mutants with unknown phenotypes to help assign a phenotype.