Carnegie Institution for Science, Department of Embryology, 3520 San Martin Drive Baltimore, MD 21218, USA; Department of Biology, The Johns Hopkins University, Baltimore, MD 21218, USA.
Carnegie Institution for Science, Department of Embryology, 3520 San Martin Drive Baltimore, MD 21218, USA; Department of Biology, The Johns Hopkins University, Baltimore, MD 21218, USA.
Semin Cell Dev Biol. 2018 Jun;78:107-115. doi: 10.1016/j.semcdb.2017.10.007. Epub 2017 Nov 6.
Accumulating evidence has reinforced that the habenular region of the vertebrate dorsal forebrain is an essential integrating center, and a region strongly implicated in neurological disorders and addiction. Despite the important and diverse neuromodulatory roles the habenular nuclei play, their development has been understudied. The emphasis of this review is on the dorsal habenular nuclei of zebrafish, homologous to the medial nuclei of mammals, as recent work has revealed new information about the signaling pathways that regulate their formation. Additionally, the zebrafish dorsal habenulae have become a valuable model for probing how left-right differences are established in a vertebrate brain. Sonic hedgehog, fibroblast growth factors and Wingless-INT proteins are all involved in the generation of progenitor cells and ultimately, along with Notch signaling, influence habenular neurogenesis and left-right asymmetry. Intriguingly, a genetic network has emerged that leads to the differentiation of dorsal habenular neurons and, through localized chemokine signaling, directs the posterior outgrowth of their newly emerging axons towards their postsynaptic target, the midbrain interpeduncular nucleus.
越来越多的证据表明，脊椎动物背侧前脑的缰核区是一个重要的整合中心，也是与神经紊乱和成瘾密切相关的区域。尽管缰核发挥着重要且多样的神经调节作用，但它们的发育仍未得到充分研究。本篇综述的重点是斑马鱼的背侧缰核，与哺乳动物的内侧核同源，因为最近的研究揭示了调节其形成的信号通路的新信息。此外，斑马鱼背侧缰核已成为探究脊椎动物大脑中左右差异是如何建立的有价值的模型。声猬因子、成纤维细胞生长因子和 Wingless-INT 蛋白都参与了祖细胞的产生，最终与 Notch 信号一起影响缰核神经发生和左右不对称性。有趣的是，一个遗传网络的出现导致了背侧缰核神经元的分化，并通过局部趋化因子信号引导它们新出现的轴突向其突触后靶标，中脑脚间核的后向生长。
