Leech neurogenesis. II. Mesodermal control of neuronal patterns.
Leech neurogenesis. II. Mesodermal control of neuronal patterns.
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水蛭神经发生。
DOI：
10.1016/0012-1606(89)90129-2
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发表时间：
1989
影响因子：
2.7
通讯作者：
Stuart,DK
中科院分区：
文献类型：
--
作者：
Torrence,SA;Law,MI;Stuart,DK
本文分析了去除舌管水蚤单侧或双侧胚胎中胚层对外胚层细胞分化和分布的影响，特别是发现了来自双侧细胞系n带的外周神经元和中枢5-羟色胺(5-羟色胺)神经元。在缺乏中胚层的区域，虽然5-羟色胺神经元经历了神经化学分化并生长了轴突，但没有形成节段性半神经节，已鉴定的神经元也没有组织成可识别的模式。在单侧中胚层剥夺的胚胎中，在中体实验区形成节段性半神经节，从剥夺侧异常越过腹中线的细胞产生已识别的神经元，这些神经元作为额外的细胞并入非剥夺侧半神经节的正常组织中。在后方实验区，两侧神经节细胞形态被破坏。我们的结论是，前体细胞致力于特定的神经元命运，无论它们是否占据正常的位置，中胚层组织为这些前体细胞找到适合其命运的位置提供必要的位置线索。
This paper reports analyses of the effects of eliminating mesoderm from one or both sides of embryos of the glossiphoniid leechTheromyzon rudeon the differentiation and distribution of ectodermal cells, especially identified peripheral neurons and central 5-hydroxytryptamine (5-HT)-containing neurons arising from the bilateral pair of cell lines called the n bandlets (n-kinship cells). In mesoderm-deprived regions, no segmental hemiganglia formed, and identified neurons were not organized into recognizable patterns, although 5-HT neurons underwent neurochemical differentiation and grew axons. In unilaterally mesoderm-deprived embryos, segmental hemiganglia were formed in a midbody experimental zone, and cells that had abnormally crossed the ventral midline from the deprived side gave rise to identified neurons that were incorporated as supernumeraries into the normal organization of hemiganglia on the nondeprived side. In a posterior experimental zone, ganglionic morphology was disrupted on both sides. We conclude that precursor cells are committed to specific neuronal fates regardless of whether they occupy normal positions and that mesodermal tissues provide positional cues necessary for such precursor cells to find positions appropriate to their fates.