Fractionation of central nervous system myelin proteins by reversed-phase high-performance liquid chromatography

Chromatographic fractionation of central nervous system myelin proteins is hampered by their poor solubility in water and strong association with lipids. Moreover, several myelin membrane proteins undergo posttranslational acylation which further increases their hydrophobicity. Here, a method is described for a two-step delipidation and high-resolution fractionation by reversed-phase high-performance liquid chromatography of all myelin proteins. The elution was monitored of the two major protein components, i.e. myelin basic protein (MBP) and proteolipid protein (PLP), as well as of minor components, viz. myelin-associated glycoprotein (MAG) and myelin/oligodendrocyte glycoprotein (MOG). Whereas MBP and MOG elute as single sharp protein peaks upon chromatography, PLP and MAG are resolved into several different components. Following their delipidation and separation, all proteins including the hydrophobic transmembrane proteins can be transferred to fully aqueous solutions without detergents. The overall yield of myelin proteins obtained in this way exceeds 85%.