1. A synthetic small molecule stalls pre-mRNA splicing by promoting an early-stage U2AF2-RNA complex
- Author
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Chatrikhi, Rakesh, Feeney, Callen F, Pulvino, Mary J, Alachouzos, Georgios, MacRae, Andrew J, Falls, Zackary, Rai, Sumit, Brennessel, William W, Jenkins, Jermaine L, Walter, Matthew J, Graubert, Timothy A, Samudrala, Ram, Jurica, Melissa S, Frontier, Alison J, and Kielkopf, Clara L
- Subjects
Genetics ,Cancer ,5.1 Pharmaceuticals ,Development of treatments and therapeutic interventions ,Female ,HEK293 Cells ,Humans ,K562 Cells ,Molecular Docking Simulation ,Molecular Structure ,RNA Precursors ,RNA Splicing ,RNA ,Neoplasm ,Small Molecule Libraries ,Splicing Factor U2AF ,S34F mutant ,U2AF(35) ,U2AF(65) ,U2AF1 ,myelodysplastic syndrome ,ribonucleoprotein targeting ,spliceosome inhibition ,splicing factor mutation ,therapeutic strategy - Abstract
Dysregulated pre-mRNA splicing is an emerging Achilles heel of cancers and myelodysplasias. To expand the currently limited portfolio of small-molecule drug leads, we screened for chemical modulators of the U2AF complex, which nucleates spliceosome assembly and is mutated in myelodysplasias. A hit compound specifically enhances RNA binding by a U2AF2 subunit. Remarkably, the compound inhibits splicing of representative substrates and stalls spliceosome assembly at the stage of U2AF function. Computational docking, together with structure-guided mutagenesis, indicates that the compound bridges the tandem U2AF2 RNA recognition motifs via hydrophobic and electrostatic moieties. Cells expressing a cancer-associated U2AF1 mutant are preferentially killed by treatment with the compound. Altogether, our results highlight the potential of trapping early spliceosome assembly as an effective pharmacological means to manipulate pre-mRNA splicing. By extension, we suggest that stabilizing assembly intermediates may offer a useful approach for small-molecule inhibition of macromolecular machines.
- Published
- 2021