Fig. 1

Downregulation of mRNA transcription of epiblast markers in mouse E3.5 blastocysts by JQ1 treatment. A–D, A'–D' Immunohistochemical analysis of BRD4 protein (magenta (A–D)) and DAPI (nuclei, blue (A’–D’)) staining, in the wild type at 8-cell (A, A’), 16-cell (B, B’), E3.5 (C, C’), and E4.5 (D, D’) embryos. E–R Whole-mount in situ hybridization of mouse blastocysts (stage 3) treated without JQ1 (control) (E–K) or with 5 μM JQ1 (L–R) for 3 h. Expression of Nanog (E, L), Otx2 (F, M), Sox2 (G, N), Oct3/4 (H, O), Gata6 (I, P), Sox17 (J, Q), or Cdx2 (K, R) mRNAs. S–Z RNA-fluorescence in situ hybridization (FISH) of E3.5 blastocysts treated without JQ1 (control; S–V) or with 5 μM JQ1 (W–Z) for 1 h. Nanog-specific probe (S, W), Gata6-specific probe (T, X), Oct3/4-specific probe (U, Y), or Cdx2-specific probe (V, Z) (yellow), with DAPI (nuclei, blue) staining. Nanog nascent mRNA precursors are absent in the nuclei following treatment with JQ1 (W). The sample numbers analyzed for each experiment are indicated in Additional file 19. Scale bars, 10 μm in S–Z; 25 μm in A, B, A’, B’, and E–R; 40 μm in C and C’; and 50 μm in D, D’