Identification of KLHL12 Ligands Using Fragment-Based Methods.

Area of Science:

• Biochemistry
• Molecular Biology
• Drug Discovery

Background:

• Targeted protein degradation utilizes E3 ligases to direct proteins for destruction.
• Current methods are limited by the small number of well-characterized E3 ligases.
• KLHL12 is an E3 ligase overexpressed in cancers, presenting a potential therapeutic target.

Purpose of the Study:

• To identify novel ligands for the KLHL12 E3 ligase.
• To expand the toolkit of E3 ligases available for targeted protein degradation.
• To develop small molecules for potential cancer therapy.

Main Methods:

• Nuclear Magnetic Resonance (NMR)-based screening to identify KLHL12-binding fragments.
• X-ray crystallography to determine the structure of fragment-KLHL12 complexes.
• Structure-guided optimization of initial fragment hits.

Main Results:

• Identified fragments that bind to KLHL12.
• Obtained X-ray crystal structures of KLHL12-fragment complexes.
• Developed the first small molecules with submicromolar affinity for KLHL12.

Conclusions:

• KLHL12 can be targeted by small molecules.
• These novel compounds are a foundation for developing Proteolysis Targeting Chimeras (PROTACs).
• Targeted degradation using KLHL12 ligands may offer selective cancer treatment strategies.