Smed-Evi/Wntless is required for β-catenin-dependent and -independent processes during planarian regeneration
Smed-Evi/Wntless is required for β-catenin-dependent and -independent processes during planarian regeneration
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DOI：
10.1242/dev.033761
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发表时间：
2009-03-15
期刊：
影响因子：
4.6
通讯作者：
Bartscherer, Kerstin
中科院分区：
文献类型：
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作者：
Adell, Teresa;Salo, Emili;Bartscherer, Kerstin
浮游生物仅能从身体的一小部分再生出整个动物，并已成为干细胞生物学的重要模型。为了确定依赖于Wnt生长因子的再生过程，我们分析了Evi的RNAi表型，Evi是一种分泌Wnt配体所需的跨膜蛋白。我们发现，在再生过程中，Smed-Evi功能的丧失阻止了后半身的认同，导致了类似Smed-beta-catenin1 RNAi动物的双头浮游生物。此外，我们观察到Smed-beta-catenin1 RNAi后没有发现的神经系统再生缺陷。通过系统地敲除所有可能的Smed Wnt，我们确定Smed-WntP-1和Smed-Wnt11-2是可能的后部组织者，并证明Smed-Wnt5是神经元组织和生长的调节因子。因此，我们的研究提供了证据，表明脊椎动物的WNT是再生的主要调节者，它们通过依赖于β-连环素和不依赖于β-连环素的途径发出信号。
Planarians can regenerate a whole animal from only a small piece of their body, and have become an important model for stem cell biology. To identify regenerative processes dependent on Wnt growth factors in the planarian Schmidtea mediterranea (Smed), we analyzed RNAi phenotypes of Evi, a transmembrane protein specifically required for the secretion of Wnt ligands. We show that, during regeneration, Smed-evi loss-of-function prevents posterior identity, leading to two-headed planarians that resemble Smed-beta-catenin1 RNAi animals. In addition, we observe regeneration defects of the nervous system that are not found after Smed-beta-catenin1 RNAi. By systematic knockdown of all putative Smed Wnts in regenerating planarians, we identify Smed-WntP-1 and Smed-Wnt11-2 as the putative posterior organizers, and demonstrate that Smed-Wnt5 is a regulator of neuronal organization and growth. Thus, our study provides evidence that planarian Wnts are major regulators of regeneration, and that they signal through beta-catenin-dependent and -independent pathways.