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Published on: January 29, 2015
Nitrogen fixation. Endocrine disrupters and flavonoid signalling.
J E Fox1, M Starcevic, K Y Kow
1Environmental Endocrinology Laboratory, Center for Bioenvironmental Research at Tulane and Xavier Universities, New Orleans, Louisiana 70112, USA.
Nature
|September 15, 2001
Summary
Endocrine-disrupting chemicals (EDCs) interfere with symbiotic nitrogen fixation signaling in plants. This discovery suggests commonalities between plant and animal hormone pathways, broadening the ecological impact of EDCs.
Area of Science:
- Plant biology
- Microbiology
- Environmental toxicology
Background:
- Nitrogen fixation is a crucial symbiotic process between legumes and soil bacteria, mediated by specific chemical signals.
- Endocrine-disrupting chemicals (EDCs) are known to interfere with hormone-signalling pathways in animals.
Purpose of the Study:
- To investigate whether EDCs impact the symbiotic signalling essential for nitrogen fixation in plants.
- To explore potential shared mechanisms between plant hormonal pathways and vertebrate hormone signalling.
Main Methods:
- Analysis of chemical signal interactions in legume-bacteria symbiosis.
- Assessment of EDC effects on plant-microbe communication pathways.
Main Results:
- Certain EDCs were found to disrupt the symbiotic signalling process required for nitrogen fixation.
- The study identified interference in the chemical communication critical for establishing nitrogen-fixing symbiosis.
Conclusions:
- EDCs can negatively affect nitrogen fixation, a vital ecological process.
- The findings suggest that plant hormone-like pathways may be targets for EDCs, with implications for plant health and ecosystems.
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