The notochord is an evolutionary novelty in vertebrates that functions as an important signaling center during development. Notochord ablation in chicken has demonstrated that it is crucial for pancreas development; however, the molecular mechanism has not been fully described. Here, we show that in zebrafish, the loss of function of nog2, a Bmp antagonist expressed in the notochord, impairs β cell differentiation, compatible with the antagonistic role of Bmp in β cell differentiation. In addition, we show that nog2 expression in the notochord is induced by at least one notochord enhancer and its loss of function reduces the number of pancreatic progenitors and impairs β cell differentiation. Tracing Nog2 diffusion, we show that Nog2 emanates from the notochord to the pancreas progenitor domain. Finally, we find a notochord enhancer in human and mice Nog genomic landscapes, suggesting that the acquisition of a Nog notochord enhancer occurred early in the vertebrate phylogeny and contributes to the development of complex organs like the pancreas.

脊索是脊椎动物的进化新奇，在发育过程中起着重要的信号传递中心的作用。鸡的脊索消融术表明它对胰腺发育至关重要。但是，分子机理尚未完全描述。在这里，我们显示了在斑马鱼中，在脊索中表达的Bmp拮抗剂nog2的功能丧失削弱了β细胞分化，与Bmp在β细胞分化中的拮抗作用相容。另外，我们显示了至少一种脊索增强子诱导了脊索中的nog2表达，并且其功能丧失减少了胰腺祖细胞的数量并损害了β细胞的分化。追踪Nog2扩散，我们显示Nog2从脊索向胰腺祖细胞域发出。最后，