(a,b) Embryos were injected, at one cell stage, with Scramble MO or hdac1 MO alone or in combination with hHDAC1 aurora phospho mutants and collected at 72 hours post fertilization (hpf). (a) Lateral and dorsal overviews of zebrafish embryos at 72 hpf. Arrows highlight morphological differences between embryos. hd: head, m: head melanocytes, j: jaw, e: eye, pe: pericardial edema, y: yolk, pf: pectoral ns, t: tail, ct: curled down tail, *: otoliths. (b) Flow cytometry analysis by PI staining of cell suspensions prepared from 72 hpf heads of control embryos and embryos injected at one-cell stage with hdac1 MO alone or in combination with hHDAC1 wt, hHDAC1 S406A or hHDAC1 S406E. The percentage of G2-M cells population compared with the control is reported for every sample. The average of three independent experiments was reported, standard error (SEM) was indicated by the error bars; the significance was calculated by one sample t-test algorithm. *P value < 0.05.