The isthmic organizer links anteroposterior and dorsoventral patterning in the mid/hindbrain by generating roof plate structures

摘要: During vertebrate development, an organizing signaling center, the isthmic organizer, forms at boundary between midbrain and hindbrain. This organizer locally controls growth patterning along anteroposterior axis of neural tube. On basis transplantation ablation experiments in avian embryos, we show here that, caudal midbrain, a restricted dorsal domain that call node, is both necessary sufficient for formation positioning roof plate, structure marks midline tube involved its dorsoventral patterning. unexpected because other regions tube, plate has been shown to form site fold fusion, which under influence epidermal ectoderm derived signals. In addition, node contributes cells hindbrain plates, are separated by limits cell movements. We also provide evidence mid/hindbrain involves homeogenetic mechanisms. Our observations indicate orchestrates axis.