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An Optimized Protocol for Electrophoretic Mobility Shift Assay Using Infrared Fluorescent Dye-labeled Oligonucleotides
Published on: November 29, 2016
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Protocol to detect nucleotide-protein interaction in vitro using a non-radioactive competitive electrophoretic
Fang Wang1, Ting Yao2, Wen Yang2
1Intensive Care Unit, Shenzhen Institute of Translational Medicine, Health Science Center, The First Affiliated Hospital of Shenzhen University, Shenzhen Second People's Hospital, Shenzhen 518035, China.
STAR Protocols
|October 1, 2022
Summary
This study presents a safer, competitive Electrophoretic Mobility Shift Assay (EMSA) using digoxigenin (DIG)-labeled probes. This method enhances DNA-protein binding detection, overcoming limitations of traditional radioactive probes.
Area of Science:
- Molecular Biology
- Biochemistry
Background:
- Electrophoretic Mobility Shift Assay (EMSA) is a widely used technique for studying DNA/RNA-protein interactions in vitro.
- Traditional EMSA often employs 32P-radiolabeled probes, which pose safety concerns and have a limited shelf-life.
- There is a need for safer and more stable alternatives for detecting DNA-protein binding affinities.
Purpose of the Study:
- To describe a competitive EMSA protocol utilizing digoxigenin (DIG)-labeled probes.
- To provide a safer and more robust alternative to radioactive probes for DNA-protein binding assays.
- To optimize the DIG-labeled EMSA protocol for high sensitivity and reproducibility.
Main Methods:
- Development of a competitive EMSA protocol using DIG-labeled DNA probes.
- Detailed procedures for DNA probe preparation and labeling with DIG-ddUTP.
- Optimization of protein-DNA mixture coincubation and EMSA separation.
- Implementation of competitive binding assays to quantify DNA-protein interactions.
Main Results:
- Successful implementation of a DIG-labeled competitive EMSA protocol.
- Demonstration of high sensitivity and reproducible results comparable to traditional methods.
- Overcoming safety issues and limitations associated with 32P-radiolabeled probes.
Conclusions:
- The DIG-labeled competitive EMSA offers a safe, sensitive, and reproducible method for detecting DNA-protein binding affinities.
- This optimized protocol provides a valuable alternative for researchers studying molecular interactions.
- The method enhances the utility of EMSA in various biological research settings.
