Defining the polycystin pharmacophore through high-throughput screening and computational biophysics.

background and purposePolycystins (PKD2, PKD2L1) are voltage-gated and Ca EXPERIMENTAL APPROACH: HEK293 cells stably expressing PKD2L1 F514A were screened pharmacologically via high-throughput electrophysiology to identify potent polycystin channel modulators. In silico docking analysis and mutagenesis were used to define the receptor sites of screen hits. Inhibition by membrane-impermeable QX-314 was used to evaluate PKD2L1-binding site accessibility. KEY

resultsScreen results identify potent PKD2L1 inhibitors with divergent chemical core structures and highlight striking similarities between the molecular pharmacology of PKD2L1 and voltage-gated sodium channels. Docking analysis, channel mutagenesis and electrophysiological recordings identify an open-state accessible lateral fenestration receptor within the pore and a mechanism of inhibition that stabilises the PKD2L1 inactivated state. CONCLUSIONS AND IMPLICATIONS: Outcomes establish the suitability of our approach to expand our chemical knowledge of polycystins and delineate novel receptor moieties for the development of channel-specific inhibitors in TRP channel research.