EIF2AK3 and ulcerative colitis: In addition, in the last few years, our group published studies showing that EIF2AK3 and ERN1, genes that encode PERK and IRE1 activation, respectively, were upregulated in intestinal mucosa from patients with CD but not in the mesenteric adipose tissue [20], and also in patients with ulcerative colitis, another form of IBD [21].