Figure 6. Aspartate is the Key Biosynthetic Precursor Provided by Respiration.
(A) Proliferation rate of 143B CytB cells determined in the presence or absence of aspartate. (B) The proliferation rate of 143B cells cultured with or without aspartate in the presence of the mitochondrial respiration inhibitors rotenone (Rot), phenformin (Phen), antimycin (Ant), myxothiazol (Myxo), azide (N3), or oligomycin (Oligo). (C) The proliferation rate of A172, H1299, HeLa, U87, FL5.12, and MEF cells cultured with or without aspartate in the presence of rotenone, antimycin, or oligomycin. (D) Schematic detailing the role of respiration and exogenous electron acceptors in aspartate biosynthesis. The conversion of nutrients into aspartate requires the removal of electrons and therefore requires access to electron acceptors, which can be supplied by respiration (O2) or exogenous electron acceptors such as AKB. Maintenance of aspartate pools supports nucleotide and protein biosynthesis. Values in all figure panels denote mean ± SEM, n=3. See also Figure S5.