Ishii Y, Abu-Elmagd M, Scotting P J
Nottingham Children's Brain Tumour Research Centre, University of Nottingham, Nottingham, NG7 2UH, United Kingdom.
Dev Biol. 2001 Aug 15;236(2):344-53. doi: 10.1006/dbio.2001.0318.
The epibranchial placodes are ectodermal thickenings that generate sensory neurons of the distal ganglia of the branchial nerves. Although significant advances in our understanding of neurogenesis from the placodes have recently been made, the events prior to the onset of neurogenesis remain unclear. We found that chick Sox3 (cSox3) shows a highly dynamic pattern of expression before becoming confined to the final placodes: one pre-otic (geniculate) and three post-otic (one petrosal and two nodose) placodes. A fate-mapping study using lipophilic dyes revealed that all post-otic placodes arise within a single broad cSox3-positive domain, where cSox3 expression and epithelial thickness will be retained only in much smaller final neurogenic placodes. The data presented here suggest that post-otic placodes are remnants of a common primordium defined as a discrete domain of cSox3 expression.
鳃上神经节原基是外胚层增厚区域，可产生鳃神经远端神经节的感觉神经元。尽管最近我们对神经节原基神经发生的理解取得了重大进展，但神经发生开始之前的事件仍不清楚。我们发现，鸡Sox3（cSox3）在局限于最终的神经节原基之前表现出高度动态的表达模式：一个耳前（膝状）和三个耳后（一个岩状和两个结节状）神经节原基。一项使用亲脂性染料的命运图谱研究表明，所有耳后神经节原基都起源于一个单一的广泛cSox3阳性区域，其中cSox3表达和上皮厚度仅在小得多的最终神经发生神经节原基中保留。此处提供的数据表明，耳后神经节原基是一个共同原基的残余物，该原基被定义为cSox3表达的离散区域。
