Cell morphology and Nanog expression after TSA treatment. (a) ES cells were treated with 50 nM TSA for 12 h and then released from TSA for an additional 12 h. Cell morphology and ALP staining of the three states (ES control, ES+TSA and ES re are shown. (b) Nanog mRNA and protein levels after 2, 4, 6 and 12 h of TSA treatment (50 nM). (c) Luc activity of Nanog promoter/enhancer domains. ES cells were transfected with the indicated fusions of Nanog promoter/enhancer fragments to the luciferase reporter gene. Transfected cells were treated with TSA for 0, 4 and 8 h.