SEL1L and type 2 diabetes mellitus: mRNA levels of BIP (A), DERL1, SEC61A1, STT3A and STT3B (B), HRD1, RNF185 and SEL1L (C), and RAD23A and UBQLN1 (D), in subcutaneous (SC) and omental (OM) preadipocytes from normoglycemic (NG), IR and T2D morbidly obese subjects (n = 12, 1 technical replicate each).