Instituto de Medicina Molecular, Faculdade de Medicina da Universidade de Lisboa, 1649-028 Lisboa, Portugal.
Development. 2011 Sep;138(18):3897-905. doi: 10.1242/dev.064717.
The origin of cells that generate the blastema following appendage amputation has been a long-standing question in epimorphic regeneration studies. The blastema is thought to originate from either stem (or progenitor) cells or differentiated cells of various tissues that undergo dedifferentiation. Here, we investigate the origin of cells that contribute to the regeneration of zebrafish caudal fin skeletal elements. We provide evidence that the process of lepidotrichia (bony rays) regeneration is initiated as early as 24 hours post-amputation and that differentiated scleroblasts acquire a proliferative state, detach from the lepidotrichia surface, migrate distally, integrate into the blastema and dedifferentiate. These findings provide novel insights into the origin of cells in epimorphic appendage regeneration in zebrafish and suggest conservation of regeneration mechanisms between fish and amphibians.
肢芽切除后形成芽基的细胞起源一直是后生动物再生研究中的一个长期存在的问题。芽基被认为来源于干细胞（或祖细胞）或经历去分化的各种组织的分化细胞。在这里，我们研究了参与斑马鱼尾部骨骼元素再生的细胞的起源。我们提供的证据表明，鳞茎（骨射线）再生过程早在截肢后 24 小时就开始了，而且分化的成软骨细胞获得了增殖状态，从鳞茎表面分离出来，向远端迁移，整合到芽基中并去分化。这些发现为斑马鱼后生动物附肢再生中细胞的起源提供了新的见解，并表明鱼类和两栖类动物之间再生机制的保守性。
