Fig. 2.

ER stress and lipid metabolism. ER stress and UPR induction alters expression of genes in lipid metabolism. PERK/eIF2α phosphorylation activates SREBP-1c and SREBP-2. ATF4 upregulates expression of SCD1, FAS, ACC, and SREBP-1c. CHOP also negatively regulates the activity of C/EBPα and C/EBPβ. IRE1α is involved in lipid metabolism by suppressing the expression of C/EBPβ, C/EBPδ, and PPARγ. XBP1s regulated expression of SCD1, DGAT2, and ACC. ATF6α interacts with the nuclear form of SREBP-2 to antagonize SREBP-2-mediated transcription of lipogenic genes. ATF6α also upregulates SREBP-1c expression.