Fig. 1: Structure-based ENT1 inhibitor design.
From: Design of an equilibrative nucleoside transporter subtype 1 inhibitor for pain relief
a Structural overlay of NBMPR and dilazep in the central cavity of hENT1cryst, with shared and distinct inhibitor binding sites labeled. b Chemical structure of dilazep and the rationally designed adenosine reuptake inhibitor, JH-ENT-01. The new inhibitor contains chemical moieties analogous to features of both dilazep and NBMPR. c Inhibitory constants (Ki) from cold-competition displacement of [3H]-NBMPR from hENT1cryst by dilazep of JH-ENT-01 (scintillation proximity assay; n = 6 technical replicates across biological duplicates; mean ± s.e.m. shown). d X-ray crystal structure of JH-ENT-01 complexed to hENT1cryst. e hENT1 and hENT2 dependent [3H]-adenosine (ado) uptake and their inhibition by dilazep and JH-ENT-01 (n = 2–3 biological replicate titrations with technical triplicates, mean ± s.e.m. shown). f Structural overlay of JH-ENT-01 and NBMPR shows a difference of para-nitrobenzyl group binding poses within opportunistic site 2. g Comparison of [3H]-adenosine uptake block in oocytes expressing WT or G154S hENT1 by NBMPR, dilazep, or JH-ENT-01 (n = 3 biological replicates, mean ± s.e.m.; P values indicated from non-paired parametric t-test).
