BHLHA15 and hereditary elliptocytosis: The inability to activate this pathway in response to environmental stressors would be detrimental to the pancreas, and our previous work showed that Mist1−/− mice exhibited increased severity following CIP coincident with a greatly reduced UPR response, We have shown here that Mist1−/− pancreatic tissue has a higher levels of UPR activity compared to WT mice under normal conditions, However, unlike the WT response to LDC-E and LDC-HE diets, there is no further increase in UPR activity in response to ethanol feeding.