Ancient vertebrate dermal armor evolved from trunk neural crest.
古代脊椎动物皮骨甲源自躯干神经嵴

Authors / 作者: Stundl J, Martik ML, Chen D, Raja DA, Franěk R, Pospisilova A, Pšenička M, Metscher BD, Braasch I, Haitina T, Cerny R, Ahlberg PE, Bronner ME.
Journal / 期刊: Proceedings of the National Academy of Sciences of the United States of America
Year / 年份: 2023
DOI: 10.1073/pnas.2221120120
Publisher / 出版社: https://www.pnas.org/doi/10.1073/pnas.2221120120
Abstract source / 摘要来源: https://europepmc.org/article/MED/37459514

Author abstract / 作者原文摘要
Bone is an evolutionary novelty of vertebrates, likely to have first emerged as part of ancestral dermal armor that consisted of osteogenic and odontogenic components. Whether these early vertebrate structures arose from mesoderm or neural crest cells has been a matter of considerable debate. To examine the developmental origin of the bony part of the dermal armor, we have performed in vivo lineage tracing in the sterlet sturgeon, a representative of nonteleost ray-finned fish that has retained an extensive postcranial dermal skeleton. The results definitively show that sterlet trunk neural crest cells give rise to osteoblasts of the scutes. Transcriptional profiling further reveals neural crest gene signature in sterlet scutes as well as bichir scales. Finally, histological and microCT analyses of ray-finned fish dermal armor show that their scales and scutes are formed by bone, dentin, and hypermineralized covering tissues, in various combinations, that resemble those of the first armored vertebrates. Taken together, our results support a primitive skeletogenic role for the neural crest along the entire body axis, that was later progressively restricted to the cranial region during vertebrate evolution. Thus, the neural crest was a crucial evolutionary innovation driving the origin and diversification of dermal armor along the entire body axis.

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
活体谱系追踪显示，小体鲟躯干神经嵴细胞形成骨板成骨细胞。鲟骨板与多鳍鱼鳞片的转录证据以及皮骨甲比较成像，支持神经嵴对祖先骨骼组织作出广泛贡献。
In vivo lineage tracing showed that sterlet sturgeon trunk neural crest cells generate scute osteoblasts. Transcriptional evidence in sturgeon scutes and bichir scales and comparative imaging of dermal armour support a broad neural-crest contribution to ancestral skeletal tissues.

Conclusions / 结论
神经嵴可能原本沿全身轴具有成骨作用，后来才更局限于头部；鲟鱼由此为脊椎动物皮骨甲起源提供发育证据。
Neural crest likely had an ancestral skeletogenic role along the body axis that became more cranially restricted later. Sturgeon therefore provides developmental evidence relevant to the origin of vertebrate dermal armour.

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.