コメント on "質量スペクトロメトリーで明らかにされたマストドンとティラノサウルスのタンパク質配列"
Pavel A Pevzner1, Sangtae Kim, Julio Ng
1Department of Computer Science and Engineering, University of California, San Diego, 9500 Gilman Drive, Mail Code 0404, La Jolla, CA 92093-0404, USA. ppevzner@cs.ucsd.edu
Science (New York, N.Y.)
|August 23, 2008
まとめ
鳥と恐竜を結びつけるタイラノサウルスのレックスタンパク質の配列が疑問視されている. 研究者らは,タンパク質データは人工物である可能性を示唆し,検証のために完全なデータリリースを要求している.
科学分野:
- パレオプロテオミクスの学問
- 進化生物学の進化生物学について
- バイオインフォマティックス
背景:
- 以前の研究では,鳥類と恐竜の進化的つながりを推論するために,ティラノサウルス・レックス (T. rex) のタンパク質の配列を報告した.
- この研究は,古代のタンパク質データを用いて,鳥類と非鳥類の恐竜の進化的関係を検証することを目的とした.
研究 の 目的:
- T. rexのタンパク質シーケンシングの方法論と発見を批判的に評価する.
- 報告されたペプチドデータにおける統計的アーティファクトの可能性に対処するために.
- データの透明性を提唱し,独立した検証を可能にします.
主な方法:
- 報告されたT. rexペプチドデータのバイオ情報分析.
- 統計的有意性の評価と人工的な結果の可能性.
- タンパク質シーケンシングと系統遺伝的推論のテクニックに関する文献レビュー.
主要な成果:
- 特定されたT. rexペプチドは,本物のシーケンスではなく,統計的アーティファクトを表している可能性があります.
- データから得られた進化論的結論の信頼性に関する懸念が提起された.
- 現在のデータは,堅実な系統遺伝分析には不十分である.
結論:
- 報告されたT. rexのタンパク質配列は,さらなる検証を必要とする.
- 完全なデータ公開は,実験的および計算的検証に不可欠です.
- 鳥と恐竜の進化的関係は,より信頼できるデータで確認する必要がある.
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