OBJECTIVETo develop a method for extracting cytoskeletons and cytoskeleton-associated proteins for proteomic analysis.

METHODSA subcellular sequential proteome extraction method was exploited. The extraction procedure was optimized and controlled according to observed cell morphology changes and one- and two-dimensional electrophoresis images. The extraction efficiency and selectivity were evaluated by Western blotting and mass spectrometry.

RESULTSFour extracted fractions clearly displayed distinct patterns. Western blotting detected the fraction-marker proteins FAK, integrin-β1, histone H1 and cytokeratin 19 only in their expected fractions. About 90% of the protein spots in the cytoskeleton fraction were identified by mass spectrometry as cytoskeleton and/or its associated proteins.

CONCLUSIONThe subcellular proteome sequential fractionation method facilitates the detection of proteins of low abundance and shows a high reproducibility and selectivity, and thus can serve as an ideal pre-fractionation method prior to two-dimensional electrophoresis.

Cytoskeleton ; chemistry ; Electrophoresis, Gel, Two-Dimensional ; methods ; Humans ; Proteome ; analysis ; Proteomics ; methods ; Subcellular Fractions