Identification of a small molecule splicing inhibitor targeting UHM domains

Area of Science:

• Molecular Biology
• Biochemistry
• Cancer Research

Background:

• Splicing factor mutations are prevalent in myeloid neoplasms, blood cancers, and solid tumors.
• Cancer cells with these mutations exhibit sensitivity to spliceosome-targeting drugs.
• The limited availability of chemical probes targeting the spliceosome necessitates new therapeutic strategies.

Purpose of the Study:

• To identify novel small molecules targeting U2AF homology motifs (UHMs) for cancer therapy.
• To develop chemical probes that inhibit critical protein-protein interactions within the spliceosome.
• To evaluate the potential of UHMCP1 as an anticancer compound.

Main Methods:

• Virtual screening of a small molecule database to identify potential UHM-binding compounds.
• In vitro competition assays to confirm inhibition of SF3b155/U2AF65 interaction.
• Nuclear Magnetic Resonance (NMR) and molecular dynamics simulations to elucidate binding interactions.
• Assessment of UHMCP1's impact on RNA splicing and cancer cell viability.

Main Results:

• Identification of UHMCP1, a novel small molecule that prevents the SF3b155/U2AF65 interaction.
• NMR and molecular dynamics confirmed UHMCP1 binds to the U2AF65 UHM domain's hydrophobic pocket.
• UHMCP1 demonstrated significant impact on RNA splicing processes.
• The compound effectively reduced cancer cell viability in preliminary tests.

Conclusions:

• UHMCP1 is a potent inhibitor of the SF3b155/U2AF65 interaction, targeting the U2AF65 UHM domain.
• This novel compound affects RNA splicing and exhibits anticancer properties.
• UHMCP1 represents a promising new chemical probe for targeting spliceosome-related vulnerabilities in cancer.