Artinger K B, Chitnis A B, Mercola M, Driever W
Cardiovascular Research Center, Massachusetts General Hospital/Harvard Medical School, Charlestown, MA 02129, USA.
Development. 1999 Sep;126(18):3969-79. doi: 10.1242/dev.126.18.3969.
In the developing vertebrate nervous system, both neural crest and sensory neurons form at the boundary between non-neural ectoderm and the neural plate. From an in situ hybridization based expression analysis screen, we have identified a novel zebrafish mutation, narrowminded (nrd), which reduces the number of early neural crest cells and eliminates Rohon-Beard (RB) sensory neurons. Mosaic analysis has shown that the mutation acts cell autonomously suggesting that nrd is involved in either the reception or interpretation of signals at the lateral neural plate boundary. Characterization of the mutant phenotype indicates that nrd is required for a primary wave of neural crest cell formation during which progenitors generate both RB sensory neurons and neural crest cells. Moreover, the early deficit in neural crest cells in nrd homozygotes is compensated later in development. Thus, we propose that a later wave can compensate for the loss of early neural crest cells but, interestingly, not the RB sensory neurons. We discuss the implications of these findings for the possibility that RB sensory neurons and neural crest cells share a common evolutionary origin.
在发育中的脊椎动物神经系统中，神经嵴和感觉神经元均形成于非神经外胚层与神经板之间的边界处。通过基于原位杂交的表达分析筛选，我们鉴定出一种新的斑马鱼突变体——狭隘（nrd），它会减少早期神经嵴细胞的数量并消除罗霍恩-比尔（RB）感觉神经元。嵌合分析表明，该突变体以细胞自主方式发挥作用，这表明nrd参与了神经板外侧边界处信号的接收或解读。对突变体表型的特征描述表明，nrd是神经嵴细胞形成初级波所必需的，在此期间祖细胞会产生RB感觉神经元和神经嵴细胞。此外，nrd纯合子中神经嵴细胞的早期缺陷在发育后期得到了补偿。因此，我们提出后期的一波细胞可以补偿早期神经嵴细胞的损失，但有趣的是，不能补偿RB感觉神经元的损失。我们讨论了这些发现对于RB感觉神经元和神经嵴细胞具有共同进化起源这一可能性的意义。
