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Updated: Jul 17, 2026
An Optimized Protocol for Electrophoretic Mobility Shift Assay Using Infrared Fluorescent Dye-labeled Oligonucleotides
Published on: November 29, 2016
Assessment of small ligand-protein interactions by electrophoretic mobility shift assay using DNA-modified ligand as
Hisakage Funabashi1, Michito Ubukata, Takashi Ebihara
1Department of Biological Information, Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama , 226-8501, Japan.
Abstract:
The interaction between a small ligand and a protein were assessed by electrophoretic mobility shift assay. A sensing probe was created by modifying the model ligand, biotin, with DNA. The complex of DNA-modified ligand and anti-biotin antibody or streptavidin as a target protein was analyzed by agarose gel electrophoresis. The band corresponding to the DNA-modified ligand was shifted in the presence of the target protein, and the intensities of the shifted bands were decreased by adding increasing concentrations of free ligand ranging from 0.1 microM to 100 microM. From this calibration the concentration of ligand in the samples could be determined, allowing for evaluation of the interaction between a small ligand and its target.
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