Rescue of secretion of disease-associated misfolded glycoproteins in UGGT1 knock-out cells (360G-Wellcome-214090_Z_18_Z)

UGGT1 is the checkpoint enzyme of the endoplasmic reticulum (ER) glycoprotein folding quality control (ERQC) machinery. Many a devastating human disease is caused by a mutation causing a slightly misfolded, but nevertheless functional protein that is flagged for ER retention by UGGT1 and ultimately degraded. The Seed Award in Science will enable me to test the hypothesis that modulation of UGGT1 can rescue the secretion of the mutant, but functional, misfolded glycoprotein, and alleviate the pathogenic consequences of the mutation. Rescue of secretion by UGGT1 deletion was tested successfully once in a plant but never in animals or mammalian cells. To do this, I will follow fluorescently tagged misfolded glycoprotein mutants in UGGT1 CRISPR/Cas9 knockout and wild-type (WT) mammalian cells. I will also use mass spectrometry to compare UGGT1 knockout cells to WT cells, to determine what impact UGGT1 deletion has on the overall secretome. These experiments if successful will make the case for the development of ERQC small-molecule modulators and the establishment of a personalised medicine strategy for the therapy of glycoprotein misfolding congenital syndromes. Unlike mutant-specific pharmacological chaperone therapies, hitting UGGT1, the one and only ERQC checkpoint, would benefit patients suffering from a broad range of rare disease.