ATP-binding cassette (ABC) proteins are membrane-bound transporters that utilize ATP to pump various substrates across biological membranes. Serious pathological conditions can result when these transporters are defective, as exemplified by cystic fibrosis caused by a defective transporter, CFTR. Yor1 is an ABC transporter in budding yeast, Saccharomyces cerevisiae. In this study, we investigated the potential regulation of Yor1 by alpha-arrestins, a family of proteins that modulate trafficking and subcellular localization of membrane proteins. By examining the effects of overexpressing different alpha-arrestin proteins on Yor1 abundance, we found that upregulating the activity of specifically one alpha-arrestin protein leads to a marked elevation of the level of Yor1 and a diminished vacuolar degradation of Yor1. This observation suggests that modulating the activity of alpha-arrestin proteins may be a novel strategy for stabilizing Yor1, which could have valuable implications for the modulation of dysfunctional CFTR transporters in humans with cystic fibrosis.

Nina Cheranda would like to thank their faculty sponsor Yuqi Wang for their support of this project.