The dorsal medial region of the developing mammalian telencephalon plays a central role in the patterning of the adjacent brain regions. This review describes the development of this specialized region of the vertebrate brain, called the cortical hem, and the formation of the various cells and structures it gives rise to, including the choroid plexus, Cajal–Retzius cells and the hippocampus. We highlight the ontogenic processes that create these different forebrain derivatives from their shared embryonic origin and discuss the key signalling pathways and molecules that influence the patterning of the cortical hem. These include BMP, Wnt, FGF and Shh signalling pathways acting with Homeobox factors to carve the medial telencephalon into district progenitor regions, which in turn give rise to the choroid plexus, dentate gyrus and hippocampus. We then link the formation of the lateral ventricle choroid plexus with embryonic and postnatal neurogenesis in the hippocampus.

发育中的哺乳动物端脑的背内侧区域在相邻大脑区域的图案形成中起着核心作用。这篇综述描述了脊椎动物大脑这个特殊区域的发育，称为皮质下摆，以及它产生的各种细胞和结构的形成，包括脉络丛、Cajal-Retzius 细胞和海马体。我们强调了从它们共同的胚胎起源中产生这些不同前脑衍生物的个体发育过程，并讨论了影响皮质下摆图案的关键信号通路和分子。这些包括 BMP、Wnt、FGF 和 Shh 信号通路与同源盒因子一起作用，将内侧端脑切割成区域祖区，进而产生脉络丛、齿状回和海马。然后，我们将侧脑室脉络丛的形成与海马中的胚胎和出生后神经发生联系起来。