アピコンプレックス類の寄生虫の緑藻起源のプラスティド
S Köhler1, C F Delwiche, P W Denny
1Department of Biology, University of Pennsylvania, Philadelphia, PA 19104, USA.
Science (New York, N.Y.)
|March 7, 1997
まとめ
アピコンプレックス寄生虫は, toksoplasmosis を引き起こすような, DNA を含むユニークなオーガネルを所持しています. 系統遺伝学的分析によると,この有機体は二次エンドシンビオシス経由で緑藻から発生したことを示唆している.
科学分野:
- 寄生虫学とは,寄生虫学である.
- 分子生物学は分子生物学である.
- 進化生物学の進化生物学について
背景:
- アピコンプレックスは,核およびミトコンドリアゲノムを持つ原生類寄生虫である.
- 彼らはまた,ユニークな35キロ塩基の円形外染色体DNAをもっています.
研究 の 目的:
- アピコンプレクサにおける35キロ塩基の染色体外DNAの起源と性質を調査する.
- この遺伝的要素の進化的関係を決定する.
主な方法:
- トキソプラズマ・ゴンディ (Toxoplasma gondii) の内部にある35キロ塩基のDNAを局所化するために,イン・シットゥ・ハイブリダイゼーションを行います.
- アピコンプレクサおよび他の生物から得られたtufa遺伝子の系統遺伝分析.
主要な成果:
- 35キロ塩基のDNAは,トキソプラズマ・ゴンディ (Toxoplasma gondii) の4つの膜に結合したオルガネルに局在していた.
- 系統遺伝学的分析では,この有機細胞ゲノムをシアノバクテリアとプラスチドとグループ化し,特に緑藻のプラスチドとクラスタリングしました.
結論:
- アピコンプレクサは,二次エンドシンバイオシスを通してプラスティドを取得した.
- プラスティドは緑藻から得られた可能性があり,これらの寄生虫における重要な進化的イベントを示しています.
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