miR156調節されたSPL転写因子は,アラビドプシス・タライアナの内生的な開花経路を定義する
Jia-Wei Wang1, Benjamin Czech, Detlef Weigel
1Department of Molecular Biology, Max Planck Institute for Developmental Biology, D-72076 Tübingen, Germany.
Cell
|August 26, 2009
まとめ
植物における開花時間は,FT/FD複合体とマイクロRNA156標的SPL遺伝子の2つの経路によって制御されます. これらの経路は,MADSボックス遺伝子を活性化することによって生殖発達を促進するために収束します.
科学分野:
- 植物生物学 植物生物学
- 分子遺伝学 分子遺伝学
- 発達生物学 発達生物学とは
背景:
- 咲く時期は,日の長さなどの環境要因の影響を受ける重要な発達プロセスです.
- FLOWERING LOCUS T (FT) タンパク質とFLOWERING TIME BZIP (FD) 転写因子は,花開への移行を誘発する複合体を形成しています.
- マイクロRNAは植物の発達における規制的な役割を果たしますが,花開き経路におけるそれらの特定の関与は複雑です.
研究 の 目的:
- マイクロRNA156を標的にするSQUAMOSA PROMOTER BINDING PROTEIN-LIKE (SPL) 遺伝子の,花開の制御における役割を調査する.
- 花開の時間を調節する際にFT/FD経路とmiR156/SPL経路の関係を決定する.
- これらの経路が収束し,生殖発達を促進する分子メカニズムを解明する.
主な方法:
- 花開の時間に関連する遺伝子発現パターンの分析.
- FT/FD,miR156,およびSPL遺伝子の間の規制相互作用を調査する.
- FT/FDとSPLのダウンストリームターゲットを撮影頂点で特定する.
主要な成果:
- SPL遺伝子は,FT/FDのダウンストリームと,別々の内生的な開花経路の一部として機能します.
- miR156レベルが低下すると,SPLレベルが上昇し,開花に適した環境が生まれます.
- FT/FDとSPLは重複するターゲットに収束し,SPLはMADSボックス遺伝子を直接活性化します.
結論:
- miR156/SPLモジュールは,FT/FDモジュールとは独立して動作するが,それと収束し,開花時間を制御する.
- この2つの経路は,冗余的に,また先行的に,花を促すMADSボックス遺伝子の活性化を調節する.
- この研究は,花開の制御のための環境と内生的な信号を統合する洗練された分子枠組みを明らかにしています.
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