Figure 4.

ESK242 and ESK246 inhibit LAT3 via a mixed mode of inhibition. (A) Increasing doses of ESK242 and ESK246 inhibit [³H]-l-leucine transport in oocytes expressing LAT3 with IC₅₀ values of 281.8 ± 1.3 μM and 146.7 ± 2.4 μM, respectively. (B–C) [³H]-l-leucine dose response in the absence or presence of 50 μM or 500 μM ESK242 (B) or ESK246 (C). Data are fitted to the Michaelis–Menten equation and normalized to the maximal rate of transport of [³H]-l-leucine alone. An Eadie–Hofstee transformation was performed (inset, B–C). Data show mean ± SEM (n = 5).