Co-immunoprecipitation (Co-IP)

Cells were resuspended in ice-cold NP-40 lysis buffer (150mM sodium chloride, 1% NP-40, 50 mM Tris PH 8.0) with protease inhibitor cocktail (Roche) and centrifuged at 12 000 g for 20 min at 4°C. For FLAG-tagged proteins, the supernatants were incubated with anti-FLAG M2 affinity gel at 4°C overnight. For other immunoprecipitations, the supernatants were incubated with the indicated antibodies overnight at 4°C. Dynabeads Protein G were added for 4 h at 4°C. After washing four times with NP-40 lysis buffer, SDS loading buffer was added and boiled for 10 min. The supernatants were subjected to immunoblotting. Antibodies used were TY1 (Sigma, SAB4800032), FLAG-HRP (Sigma, F7425), BRG1 (Proteintech, 21634-1-AP), BAF155 (Proteintech, 17722-1-AP), BAF60A (Proteintech, 10998-2-AP), DPF3 (GeneTex, GTX122249), Myc (Cell Signaling Technology, 2278) and DPF3a (Custom made).