As pluripotent stem cells become primed to give rise to all bodily cell types, they begin to form the amniotic cavity in which the mammalian fetus will grow. A checkpoint that gates this transition has now been identified.

中文翻译：

---

早期胚胎受到控制。

随着多能干细胞准备好产生所有身体细胞类型，它们开始形成哺乳动物胎儿将在其中生长的羊膜腔。现在已经确定了控制此转换的检查点。