Regeneration and maintenance of the planarian midline is regulated by a slit orthologue
Regeneration and maintenance of the planarian midline is regulated by a slit orthologue
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DOI：
10.1016/j.ydbio.2007.05.006
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发表时间：
2007-07-15
影响因子：
2.7
通讯作者：
Newmark, Phillip A.
中科院分区：
文献类型：
--
作者：
Cebria, Francesc;Guo, Tingxia;Newmark, Phillip A.
在胚胎发育过程中，几个进化上保守的轴突引导线索家族协调神经系统的精确布线。淡水真涡虫的显著可塑性提供了在神经再生和维持的背景下研究这些分子的机会。在这里，我们的特点是同源的Slit家庭的指导线索，从涡虫Schmidtea mediterranea。Smed-slit沿着Planarian中线在背侧和腹侧区域表达。靶向Smed-slit的RNA干扰（RNAi）导致中线处许多新再生组织的塌陷;这些包括头神经节、腹神经索、光感受器和后消化系统。令人惊讶的是，Smed-slit RNAi敲除动物也在完整和再生的涡虫的未受伤区域的中线附近发育形态学上可区分的异位神经结构。这些结果表明，Smed狭缝不仅作为一个排斥性的线索，需要适当的中线形成再生过程中，但它也可能起到调节行为的神经前体在完整的涡虫中线。(c)2007年爱思唯尔公司All rights reserved.
Several families of evolutionarily conserved axon guidance cues orchestrate the precise wiring of the nervous system during embryonic development. The remarkable plasticity of freshwater planarians provides the opportunity to study these molecules in the context of neural regeneration and maintenance. Here we characterize a homologue of the Slit family of guidance cues from the planarian Schmidtea mediterranea. Smed-slit is expressed along the planarian midline, in both dorsal and ventral domains. RNA interference (RNAi) targeting Smed-slit results in the collapse of many newly regenerated tissues at the midline; these include the cephalic ganglia, ventral nerve cords, photoreceptors, and the posterior digestive system. Surprisingly, Smed-slit RNAi knockdown animals also develop morphologically distinguishable, ectopic neural structures near the midline in uninjured regions of intact and regenerating planarians. These results suggest that Smed-slit acts not only as a repulsive cue required for proper midline formation during regeneration but that it may also act to regulate the behavior of neural precursors at the midline in intact planarians. (c) 2007 Elsevier Inc. All rights reserved.