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高級植物におけるオクシンシグナル伝達におけるアデニリルサイクラスの識別と役割
T Ichikawa1, Y Suzuki, I Czaja
1Max Planck Institut für Züchtungsforschung, Köln, Germany.
Nature
|December 31, 1997
まとめ
循環型AMP (cAMP) は,植物細胞のより高い分裂に役割を果たします. 研究者は新しい植物アデニリルサイクラスを特定し,cAMPを証明しました.
科学分野:
- 植物分子生物学 植物分子生物学
- 細胞シグナル伝達 細胞信号伝達
- バイオケミストリー バイオケミストリー
背景:
- 循環型AMP (cAMP) は,プロカリオットとユーカリオットにおける重要なシグナル伝達分子である.
- 高級植物におけるその役割は,アデニリルサイクラースの活性が低く,cAMPレベルが低いため,歴史的に疑問視されてきた.
- 植物ホルモンオクシンは,植物細胞分裂に不可欠です.
研究 の 目的:
- 高次の植物細胞分裂におけるcAMPの役割を調査する.
- 高級植物におけるアデニリルサイクラスを特定し,特徴づけること.
主な方法:
- 活性化T-DNAタグ付けは,タバコの細胞系を生成するために使用されました.
- アデニリルサイクラスをコードする補完DNA (cDNA) が,タグされた線から分離された.
- 単離されたcDNAはEscherichia coliと酵母で発現した.
- タバコのプロトプラストは,cAMP,フォルスコリン,またはディデオキシアデノシンで処理されました.
主要な成果:
- 新型アデニリルサイクラゼcDNAがタバコから分離され,酵母アデニリルサイクラゼと類似性を示した.
- *E. coli*におけるたばこアデニリルサイクラスの発現は,cAMPレベルを上昇させた.
- イーストでの発現は,cry1変異を補完した.
- cAMPまたはフォルスコリンによる治療により,オクシンなしでたばこ原始プラストの分裂を可能にしました.
- アデニルサイクラース阻害剤ディデオキシアデノシンは,オクシン誘発の細胞増殖を阻害しました.
結論:
- 循環型AMPは,高級植物におけるオクシン誘発細胞分裂に関与する.
- 機能的なアデニリルサイクラスが高級植物で確認されています.
- この研究は,植物発達におけるcAMPシグナル伝達の重要な役割の証拠を提供します.
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