Tris glycine gels

Total cellular protein was extracted with radioimmunoprecipitation assay buffer (Sigma-Aldrich) containing protease and phosphatase inhibitors (Calbiochem, Billerica, MA, www.calbiochem.com). The Subcellular Protein Fractionation Kit was used for membrane protein extraction (Thermo Scientific). SDS-PAGE was performed with 50 μg of total proteins using 4% to 12% gradient Tris-glycine gels (LI-COR Biosciences, Lincoln, NE, www.licor.com). Western blot analysis was performed using the Quantitative Western Blot System, with secondary antibodies labeled by IRDye infrared dyes (LI-COR Biosciences). The primary antibodies were anti-CD151, anti-Olig2, anti-FLAG (Santa Cruz), anti-Sox2, anti-S⁴⁷³-pAkt, anti-total-Akt, anti-integrin α3, anti-integrin α6, anti-integrin β1 (Cell Signaling), anti-pan Cadherin (Abcam, Cambridge, MA, www.abcam.com), and anti-β-actin (Sigma-Aldrich).