Isolation of Cell-Surface and Intracellular Proteins from an Astrocyte Culture

Source: Tham, D. K. L., et al. Determining Cell-surface Expression and Endocytic Rate of Proteins in Primary Astrocyte Cultures Using Biotinylation. J. Vis. Exp. (2017). This video demonstrates the isolation of cell-surface and intracellular proteins from an astrocyte culture. The astrocyte culture is placed on ice to inhibit endocytosis, and then the cell-surface proteins are labeled with a biotinylation reagent. The cells are lysed to release the biotinylated cell-surface proteins and non-biotinylated intracellular proteins. Finally, streptavidin-coated beads are used to separate the biotinylated cell-surface proteins from the intracellular proteins.