FIG. 6.

JQ1 does not affect histone acetylation, but does antagonize HDAC inhibition in ESCs. (A) JQ1 has no significant effect on global histone H3 and H4 acetylation in ESCs. ESCs were cultured in the presence or absence of LIF (to induce differentiation) or in medium containing 1 μM JQ1 plus LIF for 24 h, then immunolabeled with antibodies against acetylated histone H3 or H4. (B) JQ1 overcomes the effects of low-dose HDAC inhibitors on ESCs. Morphological appearance by phase microscopy of ESCs cultured for 24 h in LIF-containing medium in the presence of: (a) no drug; (b) 0.5 μM JQ1; (c) 0.2 mM sodium butyrate; (d) 0.2 mM sodium butyrate plus 0.5 μM JQ1; (e) valproic acid 0.5 μM; (f) valproic acid 0.5 μM plus 0.5 μM JQ1. Color images available online at www.liebertpub.com/scd