PDF(Pubmed)
Abstract：
The trigeminal ganglion, the largest of the vertebrate cranial ganglia, is comprised of sensory neurons that relay sensations of pain, touch, and temperature to the brain. These neurons are derived from two embryonic cell types, the neural crest and ectodermal placodes, whose interactions are critical for proper ganglion formation. While the T-cell leukemia homeobox 3 (Tlx3) gene is known to be expressed in placodally-derived sensory neurons and necessary for their differentiation, little was known about Tlx3 expression and/or function in the neural crest-derived component of the developing trigeminal ganglion. By combining lineage labeling with in situ hybridization in the chick embryo, we show that neural crest-derived cells that contribute to the cranial trigeminal ganglion express Tlx3 at a time point that coincides with the onset of ganglion condensation. Importantly, loss of Tlx3 function in vivo diminishes the overall size and abundance of neurons within the trigeminal ganglion. Conversely, ectopic expression of Tlx3 in migrating cranial neural crest results in their premature neuronal differentiation. Taken together, our results demonstrate a critical role for Tlx3 in neural crest-derived cells during chick trigeminal gangliogenesis.
摘要：
三叉神经节,最大的脊椎动物颅神经节，由传递疼痛感觉的感觉神经元组成，触摸,和大脑的温度。这些神经元来自两种胚胎细胞类型，神经嵴和外胚层胎盘，它们的相互作用对正确的神经节形成至关重要。虽然已知T细胞白血病同源异型框3（Tlx3）基因在胎盘来源的感觉神经元中表达，并且是其分化所必需的，关于Tlx3在发育中的三叉神经节的神经c衍生组件中的表达和/或功能知之甚少。通过在鸡胚中将谱系标记与原位杂交相结合，我们表明，有助于颅三叉神经节的神经c衍生细胞在与神经节凝结发作一致的时间点表达Tlx3。重要的是,体内Tlx3功能的丧失减少了三叉神经节内神经元的总体大小和丰度。相反，Tlx3在迁移的颅神经cast中的异位表达导致其过早的神经元分化。一起来看,我们的结果表明Tlx3在鸡三叉神经节发生过程中在神经c衍生细胞中的关键作用。
