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Collection and Analysis of Arabidopsis Phloem Exudates Using the EDTA-facilitated Method
Published on: October 23, 2013
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An update on phloem transport: a simple bulk flow under complex regulation.
Johannes Liesche1,2, John Patrick3
1Biomass Energy Center for Arid and Semi-arid lands, Northwest A&F University, Yangling, China.
F1000Research
|December 21, 2017
Summary
The phloem network transports essential resources and signals throughout plants. This review covers recent advances in phloem transport mechanisms, sap composition, and sap flow dynamics.
Area of Science:
- Plant Biology
- Plant Physiology
- Molecular Biology
Background:
- The phloem is crucial for resource distribution and signaling in plants.
- It supplies heterotrophic organs with necessary precursors for development.
Purpose of the Study:
- Review recent advances in phloem loading and unloading mechanisms.
- Highlight unresolved questions about phloem sap composition (proteins, RNAs).
- Evaluate structure/function relationships governing long-distance phloem transport.
Main Methods:
- Literature review of recent research on phloem transport.
- Analysis of current understanding of phloem sap constituents.
- Evaluation of models for bulk flow in the transport phloem.
Main Results:
- Recent progress in understanding resource loading/unloading into the phloem network.
- Identification of knowledge gaps concerning the physiological roles of phloem sap proteins and RNAs.
- Assessment of proposed mechanisms for high-rate, long-distance sap flow.
Conclusions:
- The phloem's role in plant development and resource allocation is complex.
- Further research is needed to elucidate the functions of phloem sap components.
- Understanding phloem transport dynamics is key to plant physiology and crop improvement.
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