The ability of the pluripotent epiblast to contribute progeny to all three germ layers is thought to be lost after gastrulation. The later-forming neural crest (NC) rises from ectoderm and it remains poorly understood how its exceptionally high stem-cell potential to generate mesodermal- and endodermal-like derivatives is obtained. Here, we monitor transcriptional changes from gastrulation to neurulation using single-cell-Multiplex-Spatial-Transcriptomics (scMST) complemented with RNA-sequencing. We show maintenance of pluripotency-like signature (Nanog, Oct4/PouV, Klf4-positive) in undecided pan-ectodermal stem-cells spanning the entire ectoderm late during neurulation with ectodermal patterning completed only at the end of neurulation when the pluripotency-like signature becomes restricted to NC, challenging our understanding of gastrulation. Furthermore, broad ectodermal pluripotency-like signature is found at multiple axial levels unrelated to the NC lineage the cells later commit to, suggesting a general role in stemness enhancement and proposing a mechanism by which the NC acquires its ability to form derivatives beyond “ectodermal-capacity” in chick and mouse embryos.

原肠胚形成后，多能外胚层将后代贡献给所有三个胚层的能力被认为丧失了。后来形成的神经嵴（NC）从外胚层中产生，但人们对其如何获得产生中胚层和内胚层样衍生物的极高干细胞潜力仍知之甚少。在这里，我们使用单细胞多重空间转录组学 (scMST) 并辅以 RNA 测序来监测从原肠胚形成到神经形成的转录变化。我们显示，在神经形成后期，跨越整个外胚层的未决定的泛外胚层干细胞中的多能性特征（ Nanog 、 Oct4/PouV 、 Klf4-阳性）的维持，只有在神经形成结束时，外胚层图案化才完成，此时多能性特征出现变得仅限于 NC，挑战了我们对原肠胚形成的理解。此外，在与细胞后来形成的 NC 谱系无关的多个轴向水平上发现了广泛的外胚层多能性样特征，这表明在干性增强中的一般作用，并提出了一种机制，通过该机制 NC 获得了形成“外胚层-外胚层-外胚层”以外的衍生物的能力。鸡和小鼠胚胎中的“能力”。