季節的な生命史の可塑性に対する遺伝的混乱の影響
Amity M Wilczek1, Judith L Roe, Mary C Knapp
1Department of Ecology and Evolutionary Biology, Brown University, Providence, RI 02912, USA.
Science (New York, N.Y.)
|January 20, 2009
まとめ
アラビドプシス・タリアナの生歴は自然に様々です. 遺伝的および環境的要因,特に光熱的信号は,花開の時間を制御し,気候変動への適応のための重要な窓を開きます.
科学分野:
- 植物生物学 植物生物学
- エコロジー エコロジー エコロジー
- 進化生物学の進化生物学について
背景:
- モデル植物であるアラビドプシス・サリアナは,自然の環境で多様な生命の歴史を表現しています.
- この多様性の遺伝的および環境的要因を理解することは,環境変化に対する種の反応を予測するために極めて重要です.
研究 の 目的:
- アラビドプシス・サリアナの生命史の変異を支える遺伝的および環境的メカニズムを調査する.
- 生命史戦略の形成における花期経路の役割を解剖する.
主な方法:
- フィールド実験は,アラビドプシス・サリアナ (Arabidopsis thaliana) のヨーロッパ原産の範囲で実施されました.
- 信号伝達経路が損なわれた変異体が育てられ,その生命の歴史が分析されました.
- 遺伝子および環境データに基づいて開花時間を予測するために,光熱モデルが開発されました.
主要な成果:
- 発芽に必要な寒さに影響する突然変異は,夏末期のコホートを除いて,生命史に最小限の影響を及ぼしました.
- 光熱モデルにより,観察された生命史の変動の重要な部分を説明することが成功しました.
- このモデルは,秋から春の突然のシフトを予測し,夏の終わりに発芽する植物の開花を予測した.
結論:
- 環境信号,特に光熱信号は,開花への移行を決定的に制御します.
- この移行は,生命の歴史の特徴に対する遺伝的および気候の影響に対する敏感なウィンドウを作成します.
- 季節的に調節される生命史の特徴は,環境変化に対する感受性の共通のメカニズムを共有する可能性があります.
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