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Amino acid export in plants: a missing link in nitrogen cycling
Sakiko Okumoto1, Guillaume Pilot
1549 Latham Hall, Virginia Tech, Blacksburg, VA 24061, USA. sokumoto@vt.edu
Molecular Plant
|February 18, 2011
Summary
Plant amino acid export is crucial for nitrogen distribution. This review explores current knowledge on amino acid transporters and regulators, identifying potential exporters for better understanding plant nutrient transport.
Area of Science:
- Plant biology
- Molecular biology
- Biochemistry
Background:
- Nutrient export from source to sink organs is vital for plant development.
- Amino acids are key nitrogen compounds transported long-distance in plants via xylem and phloem.
- The molecular identity of plant amino acid exporters remains largely unknown due to identification challenges.
Purpose of the Study:
- To review current knowledge on plant amino acid export systems.
- To highlight identified amino acid transporters and potential exporters.
- To discuss regulatory genes involved in amino acid export.
Main Methods:
- Literature review of physiological and molecular studies on plant amino acid transport.
- Analysis of sequence homology to identify putative amino acid exporter proteins.
- Identification of genes potentially regulating amino acid export.
Main Results:
- Several plant amino acid transporters with bi-directional transport activity have been described.
- Evolutionary analysis suggests uncharacterized plant proteins may function as amino acid exporters.
- Genes potentially regulating amino acid export have been discovered.
Conclusions:
- Understanding amino acid exporter proteins is essential for plant nitrogen distribution.
- Further studies on putative transporters and regulators will elucidate molecular mechanisms of plant amino acid export.
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