Full regeneration of the tribasal Polypterus fin.
多鳍鱼三基式鳍的完整再生

Authors / 作者: Cuervo R, Hernández-Martínez R, Chimal-Monroy J, Merchant-Larios H, Covarrubias L.
Journal / 期刊: Proceedings of the National Academy of Sciences of the United States of America
Year / 年份: 2012
DOI: 10.1073/pnas.1006619109
Publisher / 出版社: https://www.pnas.org/doi/10.1073/pnas.1006619109
Abstract source / 摘要来源: https://europepmc.org/article/MED/22355122

Author abstract / 作者原文摘要
Full limb regeneration is a property that seems to be restricted to urodele amphibians. Here we found that Polypterus, the most basal living ray-finned fish, regenerates its pectoral lobed fins with a remarkable accuracy. Pectoral Polypterus fins are complex, formed by a well-organized endoskeleton to which the exoskeleton rays are connected. Regeneration initiates with the formation of a blastema similar to that observed in regenerating amphibian limbs. Retinoic acid induces dose-dependent phenotypes ranging from inhibition of regeneration to apparent anterior-posterior duplications. As in all developing tetrapod limbs and regenerating amphibian blastema, Sonic hedgehog is expressed in the posterior mesenchyme during fin regeneration. Hedgehog signaling plays a role in the regeneration and patterning processes: an increase or reduction of fin bony elements results when this signaling is activated or disrupted, respectively. The tail fin also regenerates but, in contrast with pectoral fins, regeneration can resume after release from the arrest caused by hedgehog inhibition. A comparative analysis of fin phenotypes obtained after retinoic acid treatment or altering the hedgehog signaling levels during regeneration allowed us to assign a limb tetrapod equivalent segment to Polypterus fin skeletal structures, thus providing clues to the origin of the autopod. We propose that appendage regeneration was a common property of vertebrates during the fin to limb transition.

Summary basis / 解读依据
摘要解读依据已查看的索引作者摘要；如已保存全文，可用于进一步阅读。
Summary based on the inspected indexed author abstract; archived full text, when available, is provided for further reading.

Key findings / 主要发现
多鳍鱼通过类似再生芽基的结构再生复杂胸鳍。维甲酸改变再生和骨骼排列，Sonic hedgehog 的表达及信号活性则影响再生骨性元件的数量与排列。
Polypterus regenerated complex pectoral fins through a blastema-like structure. Retinoic acid altered regeneration and skeletal pattern, while Sonic hedgehog expression and signaling affected the number and arrangement of regenerated bony elements.

Conclusions / 结论
共同的发育反应提示鱼鳍与两栖动物肢体再生之间存在深层联系；作者提出，附肢再生能力在鳍向肢体过渡时期已经存在。
The shared developmental responses suggest deep connections between fish fin regeneration and amphibian limb regeneration. The authors propose that appendage regeneration was present during the fin-to-limb transition.

Relevance / 关联说明
直接研究清单物种，或研究广义类群中的代表物种。
Direct research on the listed species or a representative of the broadly named group.