Addison Megan, Wilkinson David G
The Francis Crick Institute, Mill Hill Laboratory, London, United Kingdom.
The Francis Crick Institute, Mill Hill Laboratory, London, United Kingdom.
Curr Top Dev Biol. 2016;117:581-96. doi: 10.1016/bs.ctdb.2015.10.019. Epub 2016 Jan 7.
The subdivision of tissues into sharply demarcated regions with distinct and homogenous identity is an essential aspect of embryonic development. Along the anteroposterior axis of the vertebrate nervous system, this involves signaling which induces spatially restricted expression of transcription factors that specify regional identity. The spatial expression of such transcription factors is initially imprecise, with overlapping expression of genes that specify distinct identities, and a ragged border at the interface of adjacent regions. This pattern becomes sharpened by establishment of mutually exclusive expression of transcription factors, and by cell segregation that underlies formation of a straight border. In this review, we discuss studies of the vertebrate hindbrain which have revealed how discrete regional identity is established, the roles of Eph-ephrin signaling in cell segregation and border sharpening, and how cell identity and cell segregation are coupled.
将组织细分为具有明显且同质特征的界限分明的区域是胚胎发育的一个重要方面。沿着脊椎动物神经系统的前后轴，这涉及信号传导，该信号传导诱导指定区域特征的转录因子在空间上受到限制的表达。此类转录因子的空间表达最初并不精确，指定不同特征的基因存在重叠表达，且相邻区域界面处的边界参差不齐。通过建立转录因子的相互排斥表达以及形成直边界所依赖的细胞分离，这种模式得以锐化。在本综述中，我们讨论了脊椎动物后脑的研究，这些研究揭示了离散区域特征是如何建立的、Eph-ephrin信号传导在细胞分离和边界锐化中的作用，以及细胞特征和细胞分离是如何耦合的。
