The digestive tracts of many animals are epithelial tubes with specialized compartments to break down food, remove wastes, combat infection, and signal nutrient availability. C. elegans possesses a linear, epithelial gut tube with foregut, midgut, and hindgut sections. The simple anatomy belies the developmental complexity that is involved in forming the gut from a pool of heterogeneous precursor cells. Here, I focus on the processes that specify cell fates and control morphogenesis within the embryonic foregut (pharynx) and the developmental roles of the pharynx after birth. Maternally donated factors in the pregastrula embryo converge on pha-4, a FoxA transcription factor that specifies organ identity for pharyngeal precursors. Positive feedback loops between PHA-4 and other transcription factors ensure commitment to pharyngeal fate. Binding-site affinity of PHA-4 for its target promoters contributes to the progression of the pharyngeal precursors towards differentiation. During morphogenesis, the pharyngeal precursors form an epithelial tube in a process that is independent of cadherins, catenins, and integrins but requires the kinesin zen-4/MKLP1. After birth, the pharynx and/or pha-4 are involved in repelling pathogens and controlling aging.

中文翻译：

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器官形成的分子基础：来自秀丽隐杆线虫前肠的见解。


许多动物的消化道都是上皮管，具有专门的隔室，可以分解食物、清除废物、抵抗感染并发出营养可用性信号。线虫拥有线性上皮肠管，具有前肠、中肠和后肠部分。简单的解剖结构掩盖了由异质前体细胞池形成肠道所涉及的发育复杂性。在这里，我重点关注胚胎前肠（咽）内指定细胞命运和控制形态发生的过程以及出生后咽的发育作用。前原肠胚胚胎中母体捐赠的因子集中在 pha-4 上，pha-4 是一种 FoxA 转录因子，可指定咽部前体的器官身份。 PHA-4 和其他转录因子之间的正反馈回路确保对咽部命运的承诺。 PHA-4 与其靶启动子的结合位点亲和力有助于咽前体细胞向分化的进展。在形态发生过程中，咽前体形成上皮管，该过程独立于钙粘蛋白、连环蛋白和整合素，但需要驱动蛋白 zen-4/MKLP1。出生后，咽和/或 pha-4 参与抵抗病原体和控制衰老。