Deficiency of PERK in human results in Wolcott-Rallison syndrome, which is characterized by early infancy insulin-dependent diabetes and multisystemic dysfunction.
Ser51Ala mutation of eIF2α shows a deficiency in pancreatic β cells manifested by the smaller core of insulin-secreting β cells and attenuated insulin secretion, and the mice die from hypoglycemia at their early infancy.
Ins2 mutation in Akita mice disrupts disulfide bond between the α and β chain of proinsulin, which leads to the mis-folding of the mutated insulin and further induces ER stress in β cells and diabetes.
Deficiency of XBP-1 results in the impacted development of both conventional and plasmacytoid DCs. Loss of XBP-1 renders DCs vulnerable to ER stress-induced apoptosis.
Innate immune response induced by P. aeruginosa infection causes ER stress in C. elegans, and mutations with loss of function for XBP-1 lead to larval lethality.
Loss of XBP-1 in intestinal epithelial cells induces Paneth cell dysfunction and overactive epithelium, leading to impaired mucosal defense to Listeria monocytogenes and increased sensitivity to colitis, an inflammatory disease sharing similar properties with T1D. The polymorphisms within the XBP-1 gene are associated with Crohn’s disease and ulcerative colitis in humans.
Caspase-12 is involved in ER stress-induced apoptosis. Mice deficient in caspase-12 are resistant to ER stress-induced apoptosis, but remain susceptible to apoptosis induced by other stimuli.
Human caspase-4, the closest paralog of rodent caspase-12, is involved in ER stress-induced apoptosis. Knockdown of caspase-4 by siRNA reduces ER stress-induced apoptosis.