Abstract
Glycerol-3-phosphate (G3P) is an important metabolite that contributes to the growth and disease-related physiologies of prokaryotes, plants, animals and humans alike. Here we show that G3P serves as the inducer of an important form of broad-spectrum immunity in plants, termed systemic acquired resistance (SAR). SAR is induced upon primary infection and protects distal tissues from secondary infections. Genetic mutants defective in G3P biosynthesis cannot induce SAR but can be rescued when G3P is supplied exogenously. Radioactive tracer experiments show that a G3P derivative is translocated to distal tissues, and this requires the lipid transfer protein, DIR1. Conversely, G3P is required for the translocation of DIR1 to distal tissues, which occurs through the symplast. These observations, along with the fact that dir1 plants accumulate reduced levels of G3P in their petiole exudates, suggest that the cooperative interaction of DIR1 and G3P orchestrates the induction of SAR in plants.
Original language | English |
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Pages (from-to) | 421-429 |
Number of pages | 9 |
Journal | Nature Genetics |
Volume | 43 |
Issue number | 5 |
DOIs | |
State | Published - May 2011 |
Bibliographical note
Funding Information:Salicylic acid and salicylic acid glucoside were extracted and measured from ~0.3 g of fresh-weight leaf tissue, as described before35. Fatty acid, lipid and jasmonic acid extractions were carried out as described earlier13. Lipid profiling was carried out at Kansas Lipidomics Research Center Analytical Laboratory, which is supported by grants from National Science Foundation-EPSCoR program, Kansas Technology Enterprise Corporation and Kansas State University.
Funding Information:
We thank D. Smith and J. Shanklin for useful discussions, M. Goodin for providing the pSITE-2NA and TMV-MP30-GFP vectors and GFP antibodies and J. Johnson for help with gas chromatography. We thank L. Lapchyk for technical help and A. Crume for managing the plant growth facility. This work was supported by grants from the National Science Foundation (IOS#0749731) to A.K. and P.K. and United Soybean Board (#9444) to A.K.
ASJC Scopus subject areas
- Genetics