脊椎動物の脳シグナリングセンターの古代デュテロストーム起源
Ariel M Pani1, Erin E Mullarkey, Jochanan Aronowicz
1Committee on Evolutionary Biology, The University of Chicago, 1025 East 57th Street, Chicago, Illinois 60637, USA.
Nature
|March 17, 2012
まとめ
脊椎動物のシグナル伝達センターと同型である脳の発達のための古代の遺伝プログラムが,ヘミコルド類に発見されています. これは,これらの複雑な遺伝子ネットワークが脊椎動物より以前に存在し,いくつかの状動物で失われたことを示唆しています.
科学分野:
- 発達生物学 発達生物学とは
- 進化生物学の進化生物学について
- 神経科学は神経科学である.
背景:
- 脊椎動物の神経皮質シグナル伝達センターは,脳をパターン化する.
- これらのセンターは,無脊椎の状動物には存在しないか,異なるので,脊椎動物と共に進化したことを示唆している.
- 以前の研究では,頭帯状動物が祖先の帯状動物の特徴を表していると考えられていた.
研究 の 目的:
- 脊椎動物の脳の遺伝子ネットワークのパターンの進化的起源を調査する.
- 脊椎動物のシグナル伝達センターの遺伝プログラムが非帯状デウテロストームに存在するかどうかをテストする.
- デウテロストームの体パターンの祖先の状態を理解するために.
主な方法:
- ヘミコルド状のサッコグロスス・コワレフスキーにおける遺伝子発現分析.
- 比較ゲノミクスと進化的発達生物学のアプローチ.
- Fgf8/17/18,sfrp1/5,hh,wnt1.1の表現パターンを調査した.
主要な成果:
- 脊椎動物の3つのシグナルセンター (前部神経脊柱,ゾナ・リミタンズ・イントラハラミカ,静脈組織体) の同型遺伝プログラムがS. kowalevskii.で確認された.
- 特定の遺伝子 (Fgf8/17/18,sfrp1/5,hh,wnt1) は,脊椎動物のような発現パターンを表している.
- ホモログな遺伝的メカニズムは,ヘミコルダ類と脊椎動物の両方で,外皮のパターンを調節する.
結論:
- 身体のパターン形成のための複雑な遺伝的規制ネットワークは,デュテロストームの進化の初期に存在していた.
- これらのネットワークは,おそらく脊椎動物の出現以前のもので,脊椎動物の中にのみ組み立てられたものではありませんでした.
- 信号伝達センターのための遺伝子プログラムは,いくつかのコード系 (アンフィオックス,アシディアン) で退化しているかもしれないが,ヘミコルド類と脊椎動物では保持され,詳細に記述された.
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