In vitro transport of methotrexate by Drosophila Multidrug Resistance-associated Protein
Fig 2
Methotrexate transport activity of DMRPs in Sf9 inside-out vesicles.
A: Time course of MTX transport measured in the presence of 4mM Mg2+ATP at 37 ˚C using 50 μg total Sf9 membrane protein overexpressing wild type DMRP at 100μM MTX concentration. B: MTX transport activity as a function of Mg2+ ATP concentration measured at 37 ˚C for 0.5 minutes using 50 and 100 μg Sf9 IOV preparations overexpressing wild type or K687M/K1349M DMRP, respectively, at 100μM MTX concentration. C: MTX transport activity as a function of MTX concentration measured at 37 ˚C for 0.5 minutes in the presence of 4mM Mg2+ ATP concentration using 50 and 100 μg Sf9 IOV preparations overexpressing wild type or K687M/K1349M DMRP, respectively. D: MTX transport activity of the wild type DMRP in the absence or in the presence of organic anion inhibitors, MK571 and benzbromarone (BB), measured at 37˚C at 4mM Mg2+ ATP concentration using 50 μg Sf9 IOV preparations overexpressing wild-type at 300μM methotrexate. The figures depict mean values of at least three independent experiments done in at least duplicates. Of note, the standard error of the estimate of mean value (S.E.M.) is depicted for all of the data points in Fig 2, however error bars are often not visible due to the low scattering of the data. We used unpaired two tailed t-test for statistical analysis of data in 2D. Significance is indicated as *p≤0.05, **p≤0.01, ***p≤0.001 and ****p≤0.0001 between control and MK571 or BB inhibited samples.