Fig. 5. Reversibility of TSA-induced chromatin decondensation. CLSM images of the same cell nuclei before treatment with TSA (A), after incubation with 100 ng/ml TSA for 4 hours (B), and after changing to a medium without TSA and incubation for another 4 hours (C). The effect of TSA is reversible since dense chromatin regions reappeared after washing out TSA.