Structural basis of selective TRPM7 inhibition by the anticancer agent CCT128930

Area of Science:

• Molecular biology
• Pharmacology
• Structural biology

Background:

• Transient Receptor Potential (TRP) channels are implicated in numerous diseases.
• High structural similarity among TRP channels poses challenges for selective drug development.
• TRPM7 channel is crucial for cancer cell proliferation.

Purpose of the Study:

• To elucidate the molecular mechanism of selective TRPM7 inhibition by the anticancer agent CCT128930.
• To understand how CCT128930 distinguishes TRPM7 from homologous channels like TRPM6.

Main Methods:

• Cryo-electron microscopy (cryo-EM) for structural determination.
• Functional assays to assess channel activity.
• Molecular Dynamics (MD) simulations to analyze binding interactions.

Main Results:

• CCT128930 binds to the vanilloid-like (VL) site of TRPM7, stabilizing it in a closed state.
• Inhibitor binding displaces a lipid molecule from the VL site, similar to other TRPM7 inhibitors.
• Specific residues within the VL site are critical for CCT128930's selective inhibition of TRPM7 over TRPM6.

Conclusions:

• The vanilloid-like (VL) site is key for selective small molecule interaction with TRPM7.
• Understanding this mechanism provides a basis for future drug design targeting TRPM7.
• Selective TRPM7 inhibition holds potential for cancer therapy.