ヘルマフロディット系コルド動物における自己不妊性のメカニズム
Yoshito Harada1, Yuhei Takagaki, Masahiko Sunagawa
1Sugashima Marine Biological Laboratory, Graduate School of Science, Nagoya University, Sugashima, Toba 517-0004, Japan. yharada@bio.nagoya-u.ac.jp
Science (New York, N.Y.)
|March 22, 2008
まとめ
アシディアンシオナ・インテスティナリスの自己相容れない系は,2つの遺伝子局所によって制御されます. これらの位置には,自己認識を司る分子をコードする遺伝子が含まれており,近親交配を防止します.
科学分野:
- 生殖生物学 生殖生物学
- 遺伝学 遺伝学とは
- 進化生物学の進化生物学について
背景:
- ヘルマフロディット生物は,親生殖を防ぐために自己相容れない (SI) を利用します.
- 原始的な状動物,シオナ・インテスティナリスにおけるSIの分子基礎は,未だに特徴づけられていない.
研究 の 目的:
- シオナ・インテスティナリスの自己相容れないシステムを支配する分子メカニズムを解明する.
- この種の自己認識に関与する遺伝子や分子を特定する.
主な方法:
- SIを制御するロシを特定するための遺伝分析.
- 候補遺伝子の遺伝子発現と構造分析.
主要な成果:
- SIシステムは,2つの協力的な遺伝子局によって規制されています.
- 各位体は,ポリシスティン1関連受容体 (s-Themis) と繊維原型リガンド (v-Themis) 遺伝子の密接な結合のペアで構成されています.
- これらの遺伝子ペアは,v-Themisがs-Themisの第1イントロン内に位置し,反対方向に転写されています.
結論:
- 特定された遺伝子ペアは,男性と女性特有の自己認識分子として機能する可能性が高い.
- Ciona intestinalisは,異なる分子成分を使用しているにもかかわらず,開花植物と同様のSIフレームワークを共有しています.
関連する概念動画
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