Fig. 1.

Subcellular fractionation performed on mouse livers. A: After fractionation, 30 μg of total protein from each fraction are loaded on 12% SDS-PAGE to analyze the distribution of mitochondrial [VDAC, cytochrome c (Cyt c)] and ER (FACL-4, CR) markers. B–D: Lipid extraction and purification are done from 50 μl of each fraction (H, homogenate; Cyto, cytosol). The sphingolipid compositions of the fractions are then analyzed by UPLC-MS. The results are expressed in picomoles of lipid per milligram of proteins. For ceramide, SM, glucosyl-ceramide, and lactosyl-ceramide, the results represent the cumulative amount of all chain lengths (mean ± SEM).