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11:49
A Novel Saturation Mutagenesis Approach: Single Step Characterization of Regulatory Protein Binding Sites in RNA Using Phosphorothioates
Published on: August 21, 2018
Targeting a regulatory element in human thymidylate synthase mRNA
Nicholas D Brunn1, Emily Garcia Sega, Melody B Kao
1Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, 92093, USA.
Chembiochem : a European Journal of Chemical Biology
|November 13, 2012
Summary
Targeting thymidylate synthase (TS) mRNA translation can overcome chemotherapy resistance. Stabilizing ligands that bind TS mRNA inhibit protein synthesis, offering a new strategy against cancer drug resistance.
Area of Science:
- Biochemistry
- Molecular Biology
- Cancer Research
Background:
- Thymidylate synthase (TS) is crucial for DNA synthesis and a target in cancer chemotherapy.
- Tumor resistance to TS inhibitors often involves increased TS expression.
- Autoregulatory translation control of TS is linked to its overexpression.
Purpose of the Study:
- To validate targeting the TS mRNA regulatory motif with stabilizing ligands.
- To investigate methods to prevent ribosomal initiation at the TS mRNA start codon.
- To explore strategies for overcoming chemotherapy resistance.
Main Methods:
- Utilized a bicistronic expression system with the TS mRNA protein-binding site.
- Introduced mutations in the RNA as surrogates for ligand binding.
- Assessed the impact of RNA stabilization on TS protein translation.
Main Results:
- Stabilization of the TS mRNA regulatory motif suppressed TS protein translation.
- Mutations mimicking ligand binding effectively inhibited ribosomal initiation.
- Demonstrated the feasibility of targeting RNA structure to control gene expression.
Conclusions:
- Compounds stabilizing the TS mRNA motif can inhibit translation initiation.
- This approach may overcome resistance to existing TS enzyme-targeting drugs.
- Targeting TS mRNA offers a potential combination therapy strategy for cancer.
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