Endocytosis machinery is involved in aggregation of proteins with expanded polyglutamine domains.

The cell's failure to refold or break down abnormal polypeptides often leads to their aggregation, which could cause toxicity and various pathologies. Here we investigated cellular factors involved in protein aggregation in yeast and mammalian cells using model polypeptides containing polyglutamine domains. In yeast, a number of mutations affecting the complex responsible for formation of the endocytic vesicle reduced the aggregation.