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Live-cell Imaging of Fungal Cells to Investigate Modes of Entry and Subcellular Localization of Antifungal Plant Defensins
Published on: December 24, 2017
A defensin from tomato with dual function in defense and development.
Henrik U Stotz1, Brandi Spence, Yueju Wang
1Horticulture Department, Oregon State University, Corvallis, OR 97331, USA.
Plant Molecular Biology
|June 18, 2009
Summary
Tomato defensin DEF2 plays a dual role in plant immunity and reproduction. Its expression impacts flower development, pollen viability, and resistance to fungal pathogens like Botrytis cinerea.
Area of Science:
- Plant Biology
- Immunology
- Molecular Genetics
Background:
- Defensins are crucial antimicrobial peptides in innate immunity.
- They defend against pathogens by disrupting microbial membranes and mediating cellular signaling.
- Plant defensins share functional similarities with their animal counterparts.
Purpose of the Study:
- To investigate the role of tomato defensin DEF2 in plant development and defense.
- To understand the regulation of DEF2 expression during flower development.
- To explore the functional diversity of plant defensins.
Main Methods:
- Analysis of DEF2 mRNA and peptide expression during flower development.
- Gene manipulation using antisense suppression and constitutive overexpression of DEF2.
- Assessing pollen viability, seed production, and organ growth in transgenic tomatoes.
- Evaluating foliar resistance to Botrytis cinerea and testing leaf extracts for antifungal activity.
Main Results:
- DEF2 is expressed during early tomato flower development, with differential regulation of its mRNA, peptide, and processing.
- Altering DEF2 levels (suppression or overexpression) negatively impacts pollen viability and seed yield.
- Overexpression of DEF2 leads to pleiotropic effects on organ growth and enhances resistance to Botrytis cinerea.
- Leaf extracts from DEF2-overexpressing plants inhibit fungal growth.
Conclusions:
- Plant defensins, exemplified by tomato DEF2, exhibit multifaceted roles beyond direct pathogen defense.
- DEF2 is involved in regulating reproductive processes, including pollen viability and seed production.
- DEF2 contributes to both developmental processes and broad-spectrum disease resistance in plants.
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