Detection of neuronal growth inhibitory factor (metallothionein-3) in polyacrylamide gels and by Western blot analysis.

摘要

Neuronal growth inhibitory factor (GIF) is a small cysteine-rich metal binding protein downregulated in Alzheimer's disease. The protein belongs to the superfamily of metallothioneins (MTs) and was classified as MT-3. Although first identified as a brain specific protein, several reports now indicate a substantially broader expression pattern. However, currently available detection methods for MT-3 show low sensitivity in gel electrophoresis and Western blot. We have developed a fast and sensitive method for MT-3 detection in SDS-PAGE (detection limit approximately 10 ng) and Western blot (detection limit approximately 1 ng). The method is based on the chemical modification of cysteine residues with the dye monobromobimane and an improved blotting protocol.