Figure 4.

Characterization of substrate transport by mutant and wild-type SLC13 transporters. Transport of ¹⁴C-citrate, ¹⁴C-succinate and ¹⁴C-glutarate (100 μmol/L each) in sodium or choline buffers. (A) DelG mutant. Bars show mean and range, n = 2 experiments. (B) G219R mutant. Bars show means ± SEM, n = 3–4; range is shown for n = 2 (succinate, glutarate with choline). (C) Comparison of citrate, succinate and glutarate transport in wild-type NaCT, NaDC1 and NaDC3 transporters. Transport was measured in sodium buffer. Bars show means ± SEM, n = 3 replicates from single experiment. In all experiments, backgrounds were corrected by subtracting counts in pcDNA-transfected cells. Note the 25-fold difference in scale between (C) and (A), (B).