Discovery of Potent and Selective Reversible Ubiquitin-Like Modifier Activating Enzyme 5 Inhibitors Targeting the...

Area of Science:

• Biochemistry
• Molecular Biology
• Drug Discovery

Background:

• Ubiquitin-like modifier activating enzyme 5 (UBA5) is an E1 enzyme in the UFMylation pathway.
• UFMylation plays a critical role in cellular function and is a potential therapeutic target for diseases, including cancer.

Purpose of the Study:

• To discover and synthesize potent and selective noncovalent inhibitors of UBA5.
• To provide valuable tool compounds for studying the UFMylation pathway.

Main Methods:

• Structure-activity relationship optimization of a high-throughput screen hit (compound 6).
• Utilized conventional and microscale library synthesis.
• Employed surface plasmon resonance, nanodifferential scanning fluorimetry, and cellular thermal shift assays for biophysical and cellular target engagement validation.

Main Results:

• Identified compounds 49 and 50 as potent and selective noncovalent UBA5 inhibitors.
• Demonstrated inhibition of UFMylation of UBA5, UFC1, and RPL26 in retinal pigment epithelial-1 cells.
• Confirmed specificity of compounds 49 and 50 for UBA5 over other E1-E2 transesterification pathways.

Conclusions:

• Discovery and synthesis of potent and selective UBA5 inhibitors (compounds 49 and 50).
• These inhibitors show promise as tool compounds for investigating the UFMylation pathway.
• The findings support UBA5 as a viable therapeutic target in UFMylation-related diseases.