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Dissection and Flat-mounting of the Threespine Stickleback Branchial Skeleton
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超構造は,ユナノゾアの祖先の脊髄骨格を明らかにする
Qingyi Tian1,2, Fangchen Zhao2, Han Zeng2
1State Key Laboratory for Mineral Deposits Research, School of Earth Sciences and Engineering and Frontiers Science Center for Critical Earth Material Cycling, Nanjing University, Nanjing 210023, China.
Science (New York, N.Y.)
|July 20, 2022
まとめ
この研究では,ユナノゾアの枝状弧は,脊椎動物特有の細胞軟骨を有しており,脊椎動物の初期の進化におけるその役割を示唆しています. この発見はユナノゾーアを幹の脊椎動物として支持し 喉の弓の起源に光を当てています
科学分野:
- 進化生物学
- 古生物学
- 発達生物学
背景:
- 喉のアーチは脊椎動物のと脳細胞の進化に不可欠です
- 門の祖先の形は,結合していない軟骨の棒であると考えられています.
- カンブリア時代のユナノゾウの骨は,初期のアーチ進化の潜在的洞察を提供しているが,その脊椎動物の親和性は議論されている.
研究 の 目的:
- ユナノゾアの枝状弧の微細構造と化学組成を調べる
- 初期の脊椎動物の進化におけるユナノゾウの遺伝的位置を決定する.
- 脊髄骨格の進化の起源を明らかにする
主な方法:
- 詳細な構造分析のためのX線マイクロトモグラフィー
- 超構造的検査のためのスキャニングと伝送電子顕微鏡.
- 元素組成のマッピングのためのエネルギー分散スペクトロメトリ.
- 進化的関係を確かめるための 系統遺伝分析
主要な成果:
- ユナノゾアの枝状弧は,微細繊維に富んだ細胞外マトリックスを持つ細胞軟骨を示している.
- この軟骨の組成は以前は脊椎動物に限ると考えられていた特徴です
- 系統遺伝学的な分析では ユナノゾウは幹の脊椎動物である.
結論:
- ユナノゾアの枝状の解剖学は,脊椎動物のような軟骨の最も古い化石の証拠を提供します.
- これらの発見は,ユナノゾウが初期の幹脊椎動物であるという仮説を強くする.
- この研究は 喉のアーチと脊椎動物の骨格構造の初期進化を明らかにした.
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