E-cadherin is expressed in early migrating NC cells and reduced in late stream regions. (A) Schematic showing the experimental approach where X. laevis embryos were injected at the eight-cell stage with nuclear marker (H2B-RFP), and NC migration was analyzed between stages 13–16 (early) and 17–25 (late). (B and C) Time-lapse imaging was performed on embryos in which the NC was labeled with nuclear-GFP. Frames of 5-h movies were color-coded and projected at early (B) and late (C) migratory stages. (D and E) Tracks of NC at the early (D) or late (E) migratory stages. (F and G) Angular distribution of migration direction in early and late stream regions. (H and I) Quantification of nuclear speed (H) and persistence (I) reveals reduced directional persistence at late stages. (J) Transverse cryosections of early and late migratory streams. (K–Q) E-cadherin immunostaining combined with twist mRNA detection by HCR in early (K, M, and O) and late (L, N, and P) NC cells shows progressive downregulation of E-cadherin in the NC stream regions (Q). Quantification of E-cadherin fluorescence intensity in early and late stream regions. Images are representative of at least three independent experiments. Scale bars in B, C: 50 µm; K: 10 µm. Error bars indicate mean ± SEM. Statistical analysis was performed using unpaired two-tailed Student’s t test. ***P ≤ 0.001; ****P ≤ 0.0001; n.s., not significant.