Fig. 6.

The HDAC inhibitor TSA blocks maturation and affects the expression of PaHAP3A and PaVP1 during the development of somatic embryos in Norway spruce. Embryogenic cultures incubated for 4 weeks on maturation medium lacking TSA (a) or containing 10 μM TSA (b). Bars, 2 mm. Quantitative real-time PCR analysis of PaHAP3A (c) and PaVP1 (d) in embryogenic cultures treated with TSA (light bars) and control cultures without TSA (dark bars). Samples were collected during differentiation of early somatic embryos (0 weeks) and after 1–4 weeks on maturation medium. Expression values are presented as relative values to one of the samples from untreated early embryogenic cultures (0 weeks). Expression levels are shown as mean values of three biological replicates assessed three times each. Error bars indicate ±SE of biological replicates. The expression levels of TSA-treated samples (+TSA) significantly differed from the untreated control samples (−TSA) at each developmental stage for both genes, P < 0.05