Synthesis of light-activated antisense oligodeoxynucleotide
XinJing Tang1, Ivan J Dmochowski
1Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, Pennsylvania 19104-6323, USA.
Nature Protocols
|April 5, 2007
Summary
Researchers developed a light-activated antisense oligodeoxynucleotide (asODN) by linking it to a sense strand via a photocleavable linker. UV light exposure restores the asODN
Area of Science:
- Oligonucleotide chemistry
- Molecular biology
- Photochemistry
Background:
- Antisense oligodeoxynucleotides (asODNs) are used for gene silencing.
- Transiently blocking asODN activity is crucial for controlling therapeutic effects.
- Existing methods for blocking asODN activity can be complex or irreversible.
Purpose of the Study:
- To develop a method for transiently blocking and restoring asODN activity using light.
- To synthesize and characterize photoactive asODN conjugates.
- To provide a detailed protocol for the synthesis of these light-activated asODNs.
Main Methods:
- Synthesis of a 20-mer asODN conjugated to a partially complementary sense strand (sODN) via a photocleavable linker (PL).
- Formation of a stable DNA hairpin-like structure in the conjugate.
- UV light exposure (λ ≈ 365 nm) to cleave the linker and restore asODN activity.
- Purification and analysis of the synthesized photoactive asODNs.
Main Results:
- The asODN-PL-sODN conjugate forms a stable hairpin structure, preventing unintended hybridization.
- Activity of the asODN is effectively blocked in the conjugate form.
- Modest UV light exposure successfully restores asODN activity.
- The synthesis, purification, and analysis process yields good results within 1-2 weeks.
Conclusions:
- A novel photoactive asODN system has been successfully synthesized.
- This system allows for controlled, light-inducible activation of asODN activity.
- The developed method offers a promising approach for regulating oligonucleotide-based therapies.
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