Two‐dimensional gel electrophoresis of myelin and oligodendroglial proteins solubilized by a mixture of tetramethylurea and dimethylethyleneurea

A method is introduced which allows the solubilization of membrane proteins for isoelectric focusing without prior use of sodium dodecyl sulfate. Desalted and lyophilized samples of myelin and oligodendroglial membrane proteins are readily dissolved in a mixture of tetramethylurea and dimethylethyleneurea containing lysis medium. Subsequent isoelectric focusing in polyacrylamide gels reveals that the major portion of the myelin proteins focus at a rather alkaline pH. At least 6 components of the myelin basic protein can be distinguished, demonstrating its heterogeneity. Two‐dimensional gel electrophoresis reveals that the protein composition of myelin appears to be more complex than previously stated.