IMPROVEMENT OF DNA IMMOBILIZED LATEX FOR THE PURIFICATION OF TRANSCRIPTION FACTORS

Separation and purification of transcription factors have been carried out by using DNA-immobilizing sepharose gels, but this method suffers from disadvantages due to inherent gel properties. So we have prepared some non-porous poly(glycidyl methacrylate) (poly-GMA) latex particles of small sizes, on which DNA chains were immobilized by CNBr method. The device exhibited an ability to purify transcription factors via specific binding between the factor and on-surface sequence-specific DNA, but some improvements were necessary in terms of purification efficiency. In this study, styrene-GMA copolymer latex particles were prepared and coated with poly-GMA and DNA chains were directly coupled with the epoxy groups of GMA on particles. As a result, a large amount of DNA was immobilized on the latex particles. The remaining epoxy groups were masked with ethylene diamine; this suppressed non-specific adsorption of proteins effectively. One of the sequence-specific DNA binding transcription factors, E4TF3, was efficiently purified to homogeneity using the latex particles. The yield of E4TF3 was several times higher than that with the particles prepared by CNBr method.