EMT6 Plko-scramble2
3.5cm dish EMT6 cells were infected with Scramble and BRD4 knockdown lentivirus respectively. After 32h of lentivirus infection, cells were divided into 6cm dishes. Puromycin (InvivoGen #ANT-PR-1) was added at a final concentration of 1 g/ml after 12 h of cell attachment. Cells were screened with puro for 3 days and then divided into four 6 cm dishes.  Cells were collected with TRNzol (TIANGEN Cat# DP424) in RNAase-free EP tubes for subsequent RNA extraction.