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Updated: Jul 7, 2026
09:23
Imaging the Root Hair Morphology of Arabidopsis Seedlings in a Two-layer Microfluidic Platform
Published on: August 15, 2017
Local positive feedback regulation determines cell shape in root hair cells
Seiji Takeda1, Catherine Gapper, Hidetaka Kaya
1Department of Cell and Developmental Biology, John Innes Centre, Norwich NR4 7UH, UK.
Science (New York, N.Y.)
|March 1, 2008
Summary
Reactive oxygen species (ROS) produced by ROOT HAIR DEFECTIVE 2 (RHD2) NADPH oxidase stimulate calcium influx, which is essential for root hair growth. This calcium then activates RHD2, creating a positive feedback loop that maintains cell growth and determines plant cell shape.
Area of Science:
- Plant biology
- Cell biology
- Molecular genetics
Background:
- Cell morphogenesis relies on regulated growth sites.
- Root hair growth in Arabidopsis thaliana is crucial for plant development.
- Reactive oxygen species (ROS) and calcium ions (Ca2+) play roles in cellular processes.
Purpose of the Study:
- To investigate the role of ROOT HAIR DEFECTIVE 2 (RHD2) NADPH oxidase, ROS, and Ca2+ in root hair growth.
- To elucidate the regulatory mechanism maintaining active growth sites in plant cells.
- To understand how these factors determine plant cell shape.
Main Methods:
- Investigated the interaction between RHD2 NADPH oxidase, ROS production, and Ca2+ influx.
- Focused on root hair cells of Arabidopsis thaliana.
- Analyzed the positive feedback regulation between ROS and Ca2+.
Main Results:
- RHD2 NADPH oxidase-derived ROS stimulate Ca2+ influx required for root hair growth.
- Ca2+ activates RHD2 NADPH oxidase, leading to ROS production at the growing tip.
- A positive feedback loop between RHD2, ROS, and Ca2+ was identified.
Conclusions:
- The positive feedback mechanism involving RHD2, ROS, and Ca2+ maintains active growth sites in root hair cells.
- This mechanism is critical for determining the location and stability of growth sites.
- The findings demonstrate how this feedback loop influences plant cell shape during morphogenesis.
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