Computational Model

The model includes 39 species variables, 69 reactions, 37 enzymes, 129 parameters, and 38 initial concentrations. The model is a deterministic ordinary differential equation system for sphingolipid reaction-network dynamics. The model covers nine compartments or membrane faces, including cytoplasm, endoplasmic reticulum, Golgi faces, nucleus, mitochondrion, lysosome, and cell membrane leaflets. The model represents de novo ceramide synthesis as ceramide inflow into the endoplasmic reticulum rather than explicit chemistry.