OBJECTIVETo extract the plasma membrane proteins from mouse liver cells and investigate the approach for fractionating the protein mixtures by two-dimensional liquid chromatography.

METHODSThe plasma membrane of the liver cells from 10 mice was extracted by differential centrifugation and sucrose density-gradient centrifugation. The plasma membrane proteins were exchanged with the start buffer and separated by chromatofocusing in the first-dimensional fractionation. The final results were transformed into UV/pI maps using ProteoVue software.

RESULTSWe successfully extracted the plasma membrane proteins from mouse liver cells. Sixteen fractions between pH 8.5-4.0 were recovered in the first-dimensional chromatofocusing followed by 2D- chromatographic fractionation, and the results were displayed as UV/pI maps.

CONCLUSIONThis approach for fractionating the mouse liver cell plasma membrane protein study provides the foundation for further studies on the functions of plasma membrane proteins and differential proteome of diseases.