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Generation of RNA/DNA Hybrids in Genomic DNA by Transformation using RNA-containing Oligonucleotides
Published on: November 24, 2010
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An RNA-Cleaving Catalytic DNA Accelerated by Freezing
Tianmeng Yu1, Wenhu Zhou1,2, Juewen Liu1
1Department of Chemistry and Waterloo Institute for Nanotechnology, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, N2L 3G1, Canada.
Chembiochem : a European Journal of Chemical Biology
|March 15, 2018
Summary
Freezing significantly enhances the RNA-cleavage activity of the EtNa DNAzyme in the presence of sodium ions (Na+). This unique effect, not observed in other DNAzymes, is attributed to ion concentration in ice crystal microenvironments.
Area of Science:
- Biochemistry
- Molecular Biology
- Catalysis
Background:
- DNAzymes are catalytic DNA molecules with diverse applications.
- The EtNa DNAzyme exhibits unique metal ion-dependent activity.
- Understanding environmental effects on DNAzyme function is crucial for optimizing their use.
Purpose of the Study:
- To investigate the impact of freezing on the RNA-cleavage activity of the EtNa DNAzyme.
- To compare the freezing effect on EtNa with other DNAzymes.
- To elucidate the mechanism behind freezing-induced activity enhancement.
Main Methods:
- In vitro selection and characterization of the EtNa DNAzyme.
- RNA cleavage assays under various conditions (temperature, solvent, metal ions).
- Kinetic analysis to determine binding affinities (Kd) and reaction rates.
Main Results:
- EtNa DNAzyme activity is significantly enhanced by freezing in water with Na+.
- Apparent Kd for Na+ decreased over 20-fold under frozen conditions.
- Freezing inhibited EtNa with Ca2+ and most other tested DNAzymes, highlighting EtNa's unique response.
Conclusions:
- Freezing, in conjunction with Na+, dramatically enhances EtNa DNAzyme activity.
- The observed effect is sequence-specific and metal-ion dependent.
- Concentration effects within ice crystal microenvironments likely explain the enhanced activity.
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