高度な関連性は,Dictyosteliumの多細胞性を維持するために必要であり,十分である
Jennie J Kuzdzal-Fick1, Sara A Fox, Joan E Strassmann
1Department of Ecology and Evolutionary Biology, Rice University, Houston, TX 77005, USA.
Science (New York, N.Y.)
|December 17, 2011
まとめ
多細胞生物の単細胞起源は,細胞の衝突を防ぐ. Dictyostelium discoideumで確認されたこのクローン進化は,偽造細胞系統の拡散を制限することによって,協力関係を安定させます.
科学分野:
- 進化生物学の進化生物学について
- 発達生物学 発達生物学とは
- 携帯電話の協力関係
背景:
- 多細胞生物は,通常,単細胞から発生し,その過程をクローン発育と呼びます.
- このクローン起源は,細胞系統間の衝突を最小限に抑え,生物体内の協力を確保するために仮定されています.
- 協力関係を安定させるメカニズムを理解することは,複雑な生命の進化を説明するために極めて重要です.
研究 の 目的:
- クローンの発達が多細胞生物における細胞の協力を安定させるという仮説を検証する.
- 浮気細胞系統の拡散を防ぐために,親族関係が果たす役割を調査する.
- 細胞の衝突と協力に関する予測を実験的に検証する.
主な方法:
- 社会的なアメーバDictyostelium discoideumを実験的進化のモデルシステムとして利用した.
- 細胞系統の相互作用のダイナミクスを観察するために,細胞の組成と関連性を操作した.
- 異なる関係性条件下で選択圧力の影響を評価するために,突然変異の蓄積実験を行った.
主要な成果:
- 低関連性での実験的進化は,多細胞の発達を妨害する"詐欺師"変異体の出現と拡散を好む.
- 高度な関連性の条件下では,突然変異と個体内選択は,破壊的なチーターの拡散を促進するのに不十分でした.
- 変異の蓄積実験は,遺伝的関連性が高いとき,チーターが繁殖する能力が限られていることを実証しました.
結論:
- 単細胞のボトルネックは,多細胞生物における細胞協力の安定化に重要な要因である.
- 高い遺伝的関連性は,生物の整体性を脅かす浮気行動の進化を効果的に抑制します.
- クローン発達は,複雑な多細胞性にとって不可欠な協力的相互作用を維持するための強力なメカニズムを提供します.
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