An investigation into the relationship between Notch and Ero1

Ero1 is an endoplasmic reticulum (ER) resident protein responsible for PDI oxidation in disulphide bond formation. Recent work has shown a link between Ero1 and Notch pathway proteins. We wished to see if the oxidative folding of Notch was directly catalysed by the Ero-PDI pathway or if Ero1 was involved in transcriptional modulation of Notch signalling. Using western blot analysis, immunoprecipitation and immunofluorescence analysis we were able to characterise and localise relevant proteins within cells. The range of cell lines and conditions under which the Ero1 antibody 2G4 were confirmed and extended. A novel link between Ero1 and Jagged1, a notch ligand was found. In immunoprecipitation studies Ero1α was able to retrieve Jagged 1 and the opposite was also true, with Jagged 1 pulling down Ero1α as well. This suggests a novel and important link between the Ero1 and the function of the notch signalling pathway.