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Updated: Jun 20, 2026
11:06
Structural Characterization of Mannan Cell Wall Polysaccharides in Plants Using PACE
Published on: October 16, 2017
Proteins among the polysaccharides: a new perspective on root cap slime
Fushi Wen1, Gilberto Curlango-Rivera, Martha C Hawes
1Department of Plant Sciences; Division of Plant Pathology; University of Arizona; Tucson, Arizona USA.
Plant Signaling & Behavior
|August 26, 2009
Summary
Plants secrete over 100 proteins from their root caps, forming a protective
Area of Science:
- Plant Biology
- Molecular Biology
- Biochemistry
Background:
- The root cap is crucial for plant sensing and response to stimuli.
- An extracellular matrix around the root tip plays a role in plant defense.
- Border cells in the root cap are implicated in protecting the root tip.
Purpose of the Study:
- To investigate the proteins secreted by the root cap and border cells.
- To understand the role of these secreted proteins in root tip defense.
- To develop a method for quantifying the root cap's protein-based extracellular response.
Main Methods:
- Multidimensional protein analysis to identify secreted proteins.
- Microscopic assay development to quantify extracellular responses.
- Environmental stress simulations (e.g., hydroponic culture).
Main Results:
- Over 100 proteins are actively synthesized and secreted by the root cap and border cells.
- This 'root cap secretome' is vital for root tip resistance to infection.
- A new microscopic assay effectively quantifies protein-based extracellular responses.
Conclusions:
- The root cap secretome is a key component of plant defense mechanisms.
- Border cells may function analogously to white blood cells in neutralizing threats.
- The developed assay provides a tool to study plant defense strategies.
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