動物の進化と,時間的に圧縮された放射線の分子シグネチャー
Antonis Rokas1, Dirk Krüger, Sean B Carroll
1Howard Hughes Medical Institute, Laboratory of Molecular Biology, R. M. Bock Labs, University of Wisconsin-Madison, 1525 Linden Drive, Madison, WI 53706, USA.
Science (New York, N.Y.)
|December 24, 2005
まとめ
メタゾアンの系統遺伝的関係は,急速な初期の放射線による不確実なままです. この圧縮された進化史は,真菌とは異なり,広範な遺伝子配列データであっても,密接な間隔のクラドジェネティックイベントを示唆しています.
科学分野:
- 進化生物学の進化生物学について
- フィロジェネティクス フィルジェネティクス
- ゲノミクスゲノミクスとは
背景:
- メタゾーン族の進化史と関係については,ほとんど解明されていない.
- 初期の動物の進化を理解することは,生物多様性を理解するために極めて重要です.
研究 の 目的:
- 大規模な遺伝子シーケンシングを使用して,メタゾーンフィラの間の系統遺伝関係を調査する.
- メタゾーン系遺伝子の解像度を,真菌などの他の古代クラードと比較する.
主な方法:
- 多種多様なメタゾアンの分類体から,研究不足の群れを含む広範な遺伝子配列データの取得.
- 進化的関係を推論するために,配列データの系統学的分析.
- 類似の進化年齢の真菌クラードとの比較的な系統遺伝分析.
主要な成果:
- 大量のデータにもかかわらず,ほとんどのメタゾアンの属の間の系統遺伝的関係は未解決のままでした.
- 同じ遺伝子は,主要な真菌群の内部の系統遺伝関係を強固に解決した.
- 解像度の差異は,初期のメタゾアの歴史において,迅速で時間的に圧縮された放射線イベントを示唆しています.
結論:
- メタゾア群の遺伝学的な解像度の欠如は,その歴史の初期に発生した急速な放射線によるものである可能性が高い.
- この発見は,初期の動物の圧縮された進化のタイムラインを示唆する古生物学的な証拠と一致しています.
- シミュレーション分析は,急速な放射線の特徴である,近い距離のクラドジェネティックイベントが,十分な配列データさえも未解決の fylogenies を引き起こすことを支持しています.
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