English: Cell Behavior during Epiboly in a PrP-1 Morphant Embryo Time-lapse recording of gastrulation cell movements in the epiblast at 8 hpf (lateral view). The coordinated migration of blastomeres is impaired and, in general, cell cohesion in the epiblast is severely disrupted, as more rounded cells are evident, with more and larger gaps between them. Around the gaps, cells can be seen actively extending protrusions and making unstable cell contacts. Radial intercalation events take place, but morphant cells do not show the ability to flatten out and integrate within the exterior layer (see Figure 7). The recording was made over 20 min at four frames per minute. The images were converted into a video using the Axiovision 4.7 software (Zeiss).