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

Area of Science:

• Ion channel research
• Molecular pharmacology
• TRP channel family

Background:

• Polycystins (PKD2, PKD2L1) are crucial TRP ion channels implicated in brain and kidney diseases.
• Their unique trafficking and undefined pharmacophore hinder drug development.
• PKD2L1 forms constitutively active channels in the plasma membrane when overexpressed.

Purpose of the Study:

• To define the polycystin pharmacophore and identify novel modulators.
• To overcome challenges in drug screening due to polycystin trafficking.
• To develop channel-specific inhibitors for TRP channel research.

Main Methods:

• High-throughput electrophysiology screening of HEK293 cells expressing PKD2L1 F514A.
• In silico docking analysis and mutagenesis to identify receptor sites.
• Electrophysiological recordings and QX-314 inhibition to assess binding site accessibility.

Main Results:

• Identification of potent PKD2L1 inhibitors with diverse chemical structures.
• Demonstration of molecular pharmacology similarities between PKD2L1 and voltage-gated sodium channels.
• Localization of an open-state accessible lateral fenestration receptor within the pore, stabilizing the inactivated state.

Conclusions:

• The developed approach is suitable for expanding chemical knowledge of polycystins.
• Novel receptor moieties for channel-specific inhibitors have been delineated.
• This research advances the development of TRP channel modulators.