The relationship between rhombomeres and vestibular neuron populations as assessed in quail-chicken chimeras
The relationship between rhombomeres and vestibular neuron populations as assessed in quail-chicken chimeras
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DOI：
10.1006/dbio.1998.8986
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发表时间：
1998-10-01
影响因子：
2.7
通讯作者：
Glover, JC
中科院分区：
文献类型：
--
作者：
Díaz, C;Puelles, L;Glover, JC
本研究的目的是评估分割在确定后脑神经元身份中所起的作用。我们专注于两组特定的后脑神经元，即前庭脊髓神经元和前庭眼神经元，它们由不同的组组成，可以凭借其轴突投射路径来识别和区分。通过鹌鹑-鸡嵌合移植和选择性逆行轴突追踪相结合来评估菱形和前庭神经元群之间的关系。将个体鹌鹑半同形体同位且等时地移植到鸡胚宿主中。随后，用生物素缀合的葡聚糖胺逆行标记具有特定轴突轨迹的前庭脊髓和前庭眼神经元。前庭神经元群的空间域与菱形核衍生域之间的关系具有以下特点：（1）某些群源自单个菱形核； (2)一些基团源自多个连续的菱形体； (3) 两个基团占据了无法用整个菱形长度来定义的结构域； （4）一些跨越多个菱形体的群体表现出与单个菱形体相关的内部细胞结构组织； (5) 一些团体表现出有限的边界侵犯。这些结果支持这样的观点，即神经管定义域内的位置信息为神经元身份和轴突寻路的区域确定提供了基础，并且后脑分割有助于这一过程。但他们也表明分割并不是定义神经元类型的头尾域的唯一机制。此外，他们强调菱形体和神经元决定之间的关系不能简单地用分段迭代或双聚（配对规则）规范来表达。 (C) 1998 年学术出版社。
The aim of this study was to evaluate the role segmentation plays in the determination of neuronal identity in the hindbrain. We focused on two specific sets of hindbrain neurons, namely, the vestibulospinal and vestibule-ocular neurons, which comprise distinct groups that can be identified and distinguished by virtue of their axonal projection pathways. The relationship between rhombomeres and the vestibular neuron groups was assessed by a combination of quail-chicken chimeric grafting and selective retrograde axonal tracing. Individual quail hemirhombomeres were transplanted homotopically and isochronically into a chicken embryo host. Subsequently, vestibulospinal and vestibule-ocular neurons with specific axon trajectories were labeled retrogradely with biotin-conjugated dextran-amines. The relationship between the spatial domains of the vestibular neuron groups and rhombomere-derived domains had the following features: (1) some groups were derived from single rhombomeres; (2) some groups were derived from multiple contiguous rhombomeres; (3) two groups occupied domains that could not be defined in terms of whole rhombomere lengths; (4) some groups spanning multiple rhombomeres exhibited an internal cytoarchitectonic organization that related to individual rhombomeres; and (5) some groups exhibited limited boundary violation. These results support the notion that positional information within defined domains of the neural tube provides a groundplan for the regional determination of neuronal identity and axon pathfinding, and that hindbrain segmentation contributes to this process. But they also indicate that segmentation is not the only mechanism that defines the rostrocaudal domains of neuron types. Moreover, they emphasize that the relationship between rhombomeres and neuronal determination cannot be couched simply in terms of segmental iteration or of bimeric (paired rule) specification. (C) 1998 Academic Press.