炭酸 anhydrases,EPF2および新しいプロテアゼは,ストマタル発達のCO2制御を媒介する
Cawas B Engineer1, Majid Ghassemian2, Jeffrey C Anderson3
1Division of Biological Sciences, University of California San Diego, La Jolla, California 92093, USA.
Nature
|July 22, 2014
まとめ
植物は,二酸化炭素の上昇に反応して,口腔の発達を調節する. この研究では,炭素アンヒドラス (CA1,CA4) とプロテアゼ (CRSP) が,高CO2下での口腔発達の主要な抑制体として特定されています.
科学分野:
- 植物生物学 植物生物学
- 環境科学 環境科学
- 分子遺伝学 分子遺伝学
背景:
- 植物は,CO2の吸収と水の損失のバランスを取るために,口腔の密度を調節します.
- 大気中のCO2レベルが上昇すると,通常,口腔の密度が低下します.
- ストマトの発達におけるCO2感知と信号伝導のメカニズムは完全に理解されていません.
研究 の 目的:
- CO2調節された口腔の発達を支える分子メカニズムを研究する.
- 高濃度のCO2に対する植物の反応に関与する遺伝子や経路を特定する.
- この過程における炭酸アンヒドラスの役割について説明します.
主な方法:
- アラビドプシス・タリアナの炭酸アンヒドラゼダブルミュータント (ca1ca4) の分析.
- RNA-sequencing (RNA-seq) は,遺伝子発現の変化を分析するために用いられる.
- 細胞壁のプロテオミック分析により,分泌されるタンパク質を特定する.
主要な成果:
- アラビドプシスCA1CA4変異種は,CO2濃度が上昇すると口腔の発達が増加し,典型的な反応が逆転する.
- EPF2 (EPIDERMAL PATTERNING FACTOR 2) の発現は,野生型の葉が変異した葉ではなく,CO2が上昇したときに誘発される.
- 新しいCO2誘発型細胞外プロテアゼ,CRSP (CO2 RESPONSE SECRETED PROTEASE) が特定され,EPF2を分裂させ,口腔の発達を抑制することが示されました.
結論:
- 炭酸アンヒドラス (CA1,CA4) と分泌されるプロテアゼCRSPは,高濃度のCO2下での口腔発達の抑制に極めて重要です.
- CRSP媒介によるEPF2の分裂を含む細胞外信号伝達経路がCO2信号を媒介する.
- この研究は,変化する大気条件への植物適応の洞察を提供し,ガス交換を調節します.
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