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Enhanced hammerhead ribozyme turnover rates: Reevaluating therapeutic space for small catalytic RNAs
Jason M Myers1,2, Jack M Sullivan1,2,3,4,5,6
1Research Service, VA Western NY Healthcare System, Buffalo, NY 14215, USA.
Molecular Therapy. Nucleic Acids
|March 4, 2025
Summary
Enhanced hammerhead ribozymes (EhhRzs) show improved kinetic performance for targeting human rhodopsin mRNA. These novel ribozymes demonstrate potential as druggable nucleic acid therapeutics for various targets.
Area of Science:
- Molecular Biology
- Biochemistry
- RNA Therapeutics
Background:
- Hammerhead ribozymes (hhRzs) are RNA molecules with catalytic activity.
- Optimization of ribozymes for therapeutic applications is an ongoing area of research.
Purpose of the Study:
- To discover and characterize enhanced hammerhead ribozymes (EhhRzs) with improved kinetic performance.
- To evaluate the therapeutic potential of EhhRzs against the human rhodopsin mRNA target.
Main Methods:
- Development and validation of a moderate-throughput fluorescence quantitative hhRz kinetic assay.
- Structure-function assays to investigate EhhRz-substrate interactions.
- In vitro kinetic analysis including Michaelis-Menten and Mg2+ titration.
- In cellulo assessment of target knockdown at mRNA and protein levels.
Main Results:
- EhhRzs exhibited turnover activity greater than 300 nM/min under physiological conditions.
- EhhRzs demonstrated high catalytic efficiency (Vmax/Km up to 3.2 × 10^6 min^-1M^-1).
- EhhRzs showed cooperative Mg2+ dependence and effective target knockdown in cells.
Conclusions:
- EhhRzs represent a significant advancement in ribozyme technology with enhanced catalytic properties.
- EhhRzs show promise as druggable nucleic acid therapeutics for arbitrary mRNA targets.
- Further development of EhhRzs could lead to novel RNA-based therapies and aptazyme designs.
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