[Extraction of cytoskeletons and associated proteins using subcellular proteome fractionation technique]

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

A 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.

Four 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.

The 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.