The effect of various lipids on the activation of mTOR signaling. C2C12 myoblasts were stimulated for 20 minutes with vehicle (Control), or 10-30 μM of soy-derived (S) phosphatidylserine (S-PS), phosphatidylinositol (S-PI), phosphatidyl-ethanolamine (S-PE), phosphatidylcholine (S-PC), PA (S-PA), lysophosphatidic acid (S-LPA), diacylglycerol (DAG), glycerol-3-phosphate (G3P), or egg-derived PA (E-PA). The samples were then subjected to Western blot analysis for p70 phosphorylated on the threonine 389 residue (p70-389) and total p70. The ratio of these signals was calculated and used as a marker of mTOR signaling. Values in the graphs represent the mean + SEM and were obtained from 2–3 independent experiments (n = 4–12/group). * Significantly different from control (p < 0.001). # Significantly different from E-PA within each respective dose (p < 0.001).