機械的ストレスがカタニンを介して作用し,アラビドプシスの隣接する細胞間の成長率の違いを拡大します

Magalie Uyttewaal¹, Agata Burian, Karen Alim

¹Laboratoire de Reproduction et Développement des Plantes, INRA, CNRS, ENS, UCB Lyon 1, 46 Allée d'Italie, 69364 Lyon Cedex 07, France.

Cell

|April 17, 2012

まとめ

植物の幹細胞の成長は,これまで考えられていたよりも多様です. タンパク質であるカタニンは,機械的力に反応することによって,細胞成長の異質性と組織の形状に影響を与えます.

科学分野:

植物生物学植物生物学
細胞力学細胞力学
発達生物学発達生物学とは

背景:

モルフォゲン・グラディエントは,均一な組織成長を生むと考えられていた.
ショットアピカルメリステム (SAM) は,発達に不可欠な植物幹細胞のニッチです.

研究の目的:

植物組織における均質な成長モデルに異議を唱える.
SAMにおける細胞成長の変動性を調査する.
細胞成長と組織形態変異におけるカタニンの役割を決定する.

主な方法:

SAMの高解像度の定量画像作成.
野生型植物およびカタニン変異植物における細胞成長率の分析.
カタニン,マイクロチューブルの動力学,および機械力との関係を調査する.

主要な成果:

SAMの隣接する細胞の間には,著しい成長の変動がある.
カタニンの欠乏は,成長の異質性を劇的に減少させます.
カタニン変異種は,成長異質性の低下に関連した主要な形状の欠陥を示します.
カタニンは,細胞が成長によって生み出される力に反応するために不可欠です.

結論:

カタニンが媒介する微小管のダイナミクスは,細胞が機械的力に反応することを可能にします.
この細胞反応は,局所的な成長グラデーションを増幅し,異質な成長を促します.
異質な成長は,植物形態変異と組織発育に不可欠です.

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