Funded Projects

Evaluating endosomal recycling pathways in primary neurons from PWS individuals

Funding Summary

 Dr. Potts has identified a change in vesicle recycling in cells that have mutations in the MAGEL2 gene, as in Schaaf-Yang syndrome. Here, he will collaborate Dr. Larry Reiter, who has produced stem cell-based neurons from PWS ‘baby teeth’, to evaluate whether these same cellular changes are present in PWS. He will also examine ways to ‘rescue’ the defects in cellular vesicle function and receptor recycling. 

Lay Abstract

MAGEL2 is a gene frequently deleted or mutated in individuals affected with PWS. Furthermore, mice lacking MAGEL2 display symptoms similar to those seen in PWS children. However, a critical barrier to our understanding of MAGEL2’s link to PWS has been determining its function within cells. Recently, my group has solved this enigmatic question. We showed that MAGE-L2 functions to prevent aberrant degradation of proteins that normal reside in the plasma membrane. It does so through the specific modification of another protein, called WASH. This modification, termed ubiquitination, activates the WASH protein that facilitates recycling of proteins sparing them from aberrant degradation in the lysosome, the garbage can of a cell. In this proposal, we aim to determine whether MAGEL2’s function in endosomal recycling is observed in patient-derived primary neuronal cells that originate from dental pulp stem cells taken from discarded ‘baby teeth’. Furthermore, we aim to determine whether there is a genotype-to-phenotype relationship between the genetic causes of PWS (deletion or uniparental disomy; UPD), presence of autism spectrum disorder, and defects in endosomal trafficking. Finally, we aim to move beyond characterization of the cellular defects of PWS to explore proof-of-principle treatment strategies to rescue endosomal recycling pathways in the hope to discovering new therapeutic avenues.

 

Research Outcome

Publications

Emerging roles of the MAGE protein family in stress response pathways. Gee RRF, Chen H, Lee AK, Daly CA, Wilander BA, Fon Tacer K, Potts PR. (2020) Journal of Biological Chemistry. doi: 10.1074/jbc.REV120.008029

A Comprehensive Guide to the MAGE Family of Ubiquitin Ligases. Lee AK, Potts PR. Journal of Molecular Biology. 2017 Apr 21;429(8):1114-1142.

Funded Year:

2018

Awarded to:

Ryan Potts, Ph.D.

Amount:

$108,000

Institution:

St. Jude's Research Hospital

Researcher:

Ryan Potts