Covalent Docking Identifies a Potent and Selective MKK7 Inhibitor.

Area of Science:

• Cellular signaling pathways
• Molecular biology
• Drug discovery

Background:

• The c-Jun NH2-terminal kinase (JNK) pathway is vital for cellular responses to stress, inflammation, and toxins.
• While inhibitors exist for JNK and upstream kinases (MAP3Ks), selective inhibitors for MKK7, a direct activator of JNK, are lacking.

Purpose of the Study:

• To identify and develop selective covalent inhibitors for MKK7.
• To validate the efficacy and selectivity of these inhibitors.
• To explore their potential as research tools and therapeutic starting points.

Main Methods:

• Covalent virtual screening to identify initial inhibitor candidates.
• Compound optimization to achieve low-micromolar potency.
• X-ray crystallography to determine inhibitor-MKK7 binding mode.
• Proteomic analysis and kinase panels to assess selectivity.
• Validation using knockout cell lines and primary mouse B cell activation assays.

Main Results:

• Identification of selective MKK7 covalent inhibitors.
• Optimization leading to low-micromolar inhibitors of JNK phosphorylation in cells.
• Crystal structure confirming predicted binding mode.
• Demonstrated selectivity against a panel of 76 kinases.
• Validated on-target effects and inhibition of B cell activation.

Conclusions:

• Novel MKK7 covalent inhibitors were successfully developed.
• These compounds serve as valuable tools for investigating JNK signaling.
• The identified inhibitors represent potential starting points for therapeutic development targeting MKK7.