ABSTRACT
Objective To fractionate phosphoproteome of mouse liver by two-dimensional (2D) liquid phase chromatography fractionation. Methods Phosphoproteins were extracted from lysates of normal mice livers by phosphate metal affinity chromatography (PMAC) resin. The phosphoproteins were exchanged by start buffer and separated by chromatofocusing in the first dimension. Then the fractions between pH 8.5 and pH 4.0 were separated by non-porous silica (NPS) reverse-phase high performance liquid chromatography (RP-HPLC). Finally, the UV maps were converted into gel-like maps by ProteoVue software. Results Phosphoproteins of mouse liver were successfully extracted and fractionated by two dimensional liquid phase chromatographic fractionation after concentration and desalt. Then pI/UV map of mouse liver phosphoproteome was successfully set-up. There are 16 fractions between pH 8.5 and pH 4.0 after chromatofocusing in the first dimension and the UV maps of each fraction were converted into pI/UV gel-like maps. Conclusions Combination of technique of phosphoproteins enrichment and 2-D liquid phase chromatographic fractionation is an effective approach to research phosphoproteome and the key base for further identification and investigation of phosphoproteins.