Fig. 4

Palmitate-induced cisternal ER expansion is dependent on ER stress in RAW 264.7 cells. Cells were pre-treated with or without 4 mM 4-PBA or 40 μM TUDCA for 1 h and followed by treatment with 400 μM palmitate for 24 h. The phosphorylation of PERK, and the expression of BiP and CHOP were determined by western blot analysis (a). Total RNA was extracted and reverse transcribed to cDNA. Full-length and spliced XBP-1 cDNAs were amplified by PCR with mouse XBP-1 primers. Gapdh cDNA was included as an internal loading control (b). Changes in ER structure were examined by transmission electron microscopy (c)