Fig. 6. The impact of Nanog misexpression on ExE differentiation promoted by forced Sox17 expression. ESCs bearing the inducible Sox17 transgene were stably transfected with an empty vector or a constitutive Nanog expression vector. After being cultured in the absence of Tet in LIF-supplemented medium for Sox17 induction, the ESCs were allowed to aggregate and were grown in the same medium for 10 days. (A,B) Bright-field (A) and fluorescence (B) images of EBs derived from a control (Tet –, Nanog –) clone and a Nanog-misexpressing (Tet –, Nanog +) clone. Bars, 200 µm. (C,D,E) Immunostaining of the control and Nanog-misexpressing EBs with anti-Nanog (C), anti-Gata4 (D) and anti-Krt19 (E) antibodies. Bars, 50 µm. Three independent Nanog clones and two independent control clones were examined with similar results (A-E). (F) Expression of ExE markers in the control (white bars) and Nanog-misexpressing (black bars) EBs. The expression levels relative to those in the control EBs, measured by qRT-PCR, are shown as the mean ± s.d. values of three independent experiments.