Extended Data Fig. 2: Orientational dynamics and its effect on nuclear trajectories.
From: Topological interactions drive the first fate decision in the Drosophila embryo
A, Frequency distribution of tilt angle ψ is shown for an embryo during cycle 10 when they have already reached the embryo cortex. Vertical dashed line indicates 45 degrees in angle. B, Temporal traces of tilt angle ψ is shown from mid-interphase to onset of metaphase during cycle 8. Different colours indicate each unique trace of the spindle. C, The average change in tilt angle Δψ is shown for cycles 7,8 and 9. Shaded region marks the standard deviation. D, The probability distribution function of tilt angles is shown for cycle 8 and cycle 9. E, Left- The probability distribution function of tilt angles is shown for a randomized reference state. To derive the distribution one can assume a neamtic object inside a sphere oriented randomly and measure the latitude. Right- Comparison of the random distribution of angles is shown with cycle 8 and cycle 9. Measured Kullback-Leibler divergence between the random state and data from cycle 8 and cycle 9 is ~ 0.08 while between data from the two cycles is <0.01. F, Individual (grey) and average (red dots with errorbars representing 95% confidence interval of the mean) trajectories are shown for nuclei that show >45 degree with respect to the cortex at the onset of nuclear division. A clear bifurcation is indicated just after 2 min timepoint. G, Individual (gray) and average (blue dots with errorbars representing 95% confidence interval of the mean) trajectories are shown for nuclei that show <45 degree with respect to the cortex at the onset of nuclear division. A collective migration is found in the trajectories. H, A two dimensional count density map is shown for tilt angle ψ and location along the normalized anterior posterior (AP) axis for pooled 8 wild type (WT) embryos during cycle 9. Colorbar indicates the bin counts. I, Probability density function of tilt angle ψ is plotted for spindles belonging to binned locations along the AP axis with 5 equally sized bins (every 20% along the AP axis). Color indicates location along the normalized AP axis (see colorbar).
