C₄光合成を可能にする祖先の細胞アイデンティティネットワークのエクサプテーション

Joseph Swift¹, Leonie H Luginbuehl², Lei Hua³

¹Plant Biology Laboratory, Salk Institute for Biological Studies, La Jolla, CA, USA.

Nature

|November 20, 2024

まとめ

C4光合成は高度に効率的な経路であり,バンドルシート細胞を活性化する既存の cis-コードの獲得によって進化した. この発見はC4経路の進化と作物工学の洞察を与えてくれます

科学分野:

植物生物学
分子進化
生物化学

背景:

C4光合成は,祖先のC3経路と比較して,植物の生産性を大幅に高めます.
この経路は,バンドルシート細胞のCO2固定区画化を含んでいるが,その活性化のメカニズムは不明である.

研究の目的:

C4光合成におけるバンドルシート細胞のアイデンティティと活性化の基礎となる分子メカニズムを解明する.
C4光合成の進化におけるシス調節要素の役割を調査する.

主な方法:

単核遺伝子発現とクロマチンアクセシビリティアトラスを利用した.
一指 (DOF) モチーフによるDNA結合は,重要な規制要素として特定されました.

主要な成果:

C4葉のバンドルシート遺伝子発現の変化は,C3葉に存在する cis-コードの獲得と関連しています.
DOFモチーフはC3とC4の両方の作物でバンドル・シーツのアイデンティティを定義することが判明しました.
C4ソルゴの包膜細胞の光合成遺伝子はDOFで認識されたシス元素を得ました.

結論:

C4光合成は,バンドル・シーツの同一性に関連した祖先のCISコードを採用することによって進化したと考えられます.
この募集は,既存の転写因子パターンを利用して,バンドルシート細胞の光合成を活性化しました.
発見はC4の進化とC3の作物にC4の特性を組み込むための潜在的な戦略の分子洞察を提供します.

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