Fig. 8. Schematic diagram showing the cessation of gastrulation. During the early tailbud stage of chick embryos, cNog expression is initiated at the ventrolateral region of the TVM (purple indicated the Nog-expressing cells). BMP signaling could induce EMT with basal membrane (green) degradation. The chick VER shows gastrulation-like ingressive cell movement (pink indicates the ingressing cells). In the late tailbud stage of the chick embryos, cNog expression extends to the entire TVM (purple; the Nog-expressing cells) and inhibits Bmp signaling, which results in the suppression of EMT and basal membrane formation. In the early tailbud stage of mouse embryos, mNog expression in the TVM is low (light purple). The ectoderm derived from the late primitive streak shows ingressive cell movement with basal membrane degradation (pink indicates the ingressing cells and green indicates the basal membrane). In the late tailbud stage of mouse embryos, mNog is prominently expressed in the entire TVM (purple indicates the Nog-expressing cells) and inhibits BMP signaling, which results in the suppression of EMT and basal membrane formation.