Max Planck Research Group Stem Cells & Regeneration, Max Planck Institute for Molecular Biomedicine, Von-Esmarch-Str. 54, 48149 Münster, Germany; Medical Faculty, University of Münster, Albert-Schweitzer-Campus 1, 48149 Münster, Germany.
Max Planck Research Group Stem Cells & Regeneration, Max Planck Institute for Molecular Biomedicine, Von-Esmarch-Str. 54, 48149 Münster, Germany; Medical Faculty, University of Münster, Albert-Schweitzer-Campus 1, 48149 Münster, Germany; CiM-IMPRS Graduate School, Schlossplatz 5, 48149 Münster, Germany.
Dev Biol. 2014 Jun 15;390(2):136-48. doi: 10.1016/j.ydbio.2014.03.016. Epub 2014 Apr 1.
Planarians can regenerate their head within days. This process depends on the direction of adult stem cells to wound sites and the orchestration of their progenitors to commit to appropriate lineages and to arrange into patterned tissues. We identified a zinc finger transcription factor, Smed-ZicA, as a downstream target of Smed-FoxD, a Forkhead transcription factor required for head regeneration. Smed-zicA and Smed-FoxD are co-expressed with the Wnt inhibitor notum and the Activin inhibitor follistatin in a cluster of cells at the anterior-most tip of the regenerating head - the anterior regeneration pole - and in surrounding stem cell progeny. Depletion of Smed-zicA and Smed-FoxD by RNAi abolishes notum and follistatin expression at the pole and inhibits head formation downstream of initial polarity decisions. We suggest a model in which ZicA and FoxD transcription factors synergize to control the formation of Notum- and Follistatin-producing anterior pole cells. Pole formation might constitute an early step in regeneration, resulting in a signaling center that orchestrates cellular events in the growing tissue.
涡虫可以在几天内再生头部。这个过程依赖于成年干细胞向创伤部位的定向迁移，以及它们的前体细胞分化为适当谱系并排列成有组织的组织的协调。我们鉴定了一个锌指转录因子 Smed-ZicA，它是叉头转录因子 Smed-FoxD 的下游靶标，Smed-FoxD 是头部再生所必需的。Smed-zicA 和 Smed-FoxD 与 Wnt 抑制剂 notum 和 Activin 抑制剂 follistatin 一起在再生头部的最前端 - 前部再生极 - 以及周围的干细胞后代中表达。通过 RNAi 耗尽 Smed-zicA 和 Smed-FoxD 会在极区消除 notum 和 follistatin 的表达，并抑制初始极性决定下游的头部形成。我们提出了一个模型，其中 ZicA 和 FoxD 转录因子协同作用来控制 Notum 和 Follistatin 产生的前极细胞的形成。极的形成可能是再生的早期步骤，导致信号中心协调生长组织中的细胞事件。
