Somitogenesis period in <i>her1</i>, <i>her7</i> single and <i>her7;hes6</i> double mutants.

<p>Somitogenesis period was measured by multiple-embryo time-lapse microscopy. Measurements in single mutants were carried out using incrosses from heterozygous carriers, measurements in <i>her7</i> heterozygous; <i>hes6</i> homozygous and <i>her7;hes6</i> double homozygous mutants were performed with embryos obtained from crosses of trans-heterozygous and double homozygous carriers. Wildtype (wt) siblings were used as controls for single mutants, and trans-heterozygous siblings were used as controls for <i>her7;hes6</i> double mutants. Analysis was performed by an observer blind to the embryos' genotype, and measurements of somitogenesis period from individual embryos were normalized to the mean of the somitogenesis period of control embryos in the experiment. Data show mean values pooled from three separate experiments per genotype, and error bars indicate 95% confidence intervals, <i>n</i>≥25 for each genotype or control. ** indicates <i>p</i><0.01 by Mann-Whitney <i>U</i>-test, two-tailed.