Figure 4. Developmental signaling perturbations affect lineages composition and timing.

(A) Effect of Wnt activation by CHIR between 24–72 hours on Bry-GFP dynamics (green) compared to control (black), EB radius relative increase for the same experiment, and relative volume occupancy by GFP at peak Bry-GFP expression, defined as the ratio between total segmentation spots and (EB radius)³. (B) Effect of Bmp4 treatment between 24–72 hours shows early onset but reduced fraction of Bry+ points at peak. (C) Gene expression at 77 and 96 hours for Bmp4 and CHIR perturbations. Each gene is median-centered for visualization. (D) PCA for EBs harvested at 77 hours, comparing short and long Wnt induction periods to control. Percent explained variance is shown for each PC.