Related Experiment Videos
Identification and characterization of small molecule modulators of KChIP/Kv4 function.
Mark R Bowlby1, Pranab Chanda, Wade Edris
1Discovery Neuroscience, Wyeth Research, CN 8000, Princeton, NJ 08543-8000, USA. bowlbym@wyeth.com
Bioorganic & Medicinal Chemistry
|August 6, 2005
Summary
A novel diaryl-urea compound, CL-888, was identified to modulate the Kv4/KChIP complex formation. This compound alters Kv4.2/KChIP1 channel function, suggesting a conformational change induced by CL-888 binding.
Area of Science:
- Molecular biology
- Biophysics
- Pharmacology
Background:
- Potassium channels, particularly Kv4 channels, are crucial for cellular electrical excitability.
- KChIPs are subunits that modulate Kv4 channel function and complex formation.
Purpose of the Study:
- To identify small molecules that modulate the Kv4/KChIP complex.
- To investigate the mechanism of action of a identified diaryl-urea compound (CL-888).
Main Methods:
- Yeast two-hybrid assay for protein complex interaction screening.
- Biacore and size-exclusion chromatography for binding and dissociation studies.
- Electrophysiology (current amplitude and kinetics) and fluorescence spectroscopy to assess functional and binding effects.
- Molecular modeling based on KChIP1 crystal structure.
Main Results:
- CL-888 was identified as a modulator of Kv4/KChIP complex formation.
- CL-888 altered KChIP1 apparent affinity to Kv4.3-N but did not cause dissociation.
- Compound exposure changed Kv4.2/KChIP1 current amplitude and kinetics.
- Fluorescence spectroscopy and molecular modeling suggested CL-888 binds to a tryptophan-containing pocket in KChIP1.
Conclusions:
- CL-888 acts as a specific modulator of Kv4/KChIP complex function.
- The compound likely induces a conformational change in the Kv4.2/KChIP1 complex.
- Binding occurs at a specific site on KChIP1, offering insights into potassium channel modulation.