K. Nadarajah
School of BioScience and Biotechnology, Faculty of Science and Technology,
University Kebangsaan Malaysia, Bangi, Selangor, Malaysia
ABSTRACT
The system of plant defence against fungi is complex. It encompasses several cross-talking pathways that respond to various signals. Methyl jasmonate, a plant growth regulator is one of the various signals that stimulate a defence response. In order to comprehend the involvement of jasmonate in the defence of Arabidopsis against Erysiphe cruciferarum, a mutant that is defective in jasmonate accumulation, was used (fad3-2fad7-2fad8). This mutant is susceptible to E.cruciferarum infection, which results in powdery mildew. The wild type plants were resistant towards powdery mildew. Mutant plants sprayed with methyl jasmonate received substantial protection against E.cruciferarum infections. The incidence of disease in methyl jasmonate treated mutants was reduced to levels observed in the wildtype. The coi1 mutant however was not protected through treatment with methyl jasmonate. This therefore indicates that methyl jasmonate induces the plants resistance through the activation of the plants defence system and not as an antifungal agent. One of the genes activated in the defence response is the AtVSP gene. The transcript in wildtype plants was induced when infected by E.cruciferarum. Transcript levels in mutants were comparable to the constitutive levels observed in the controls. Therefore it is apparent that jasmonate-signalling is essential in protection against E.cruciferarum infections of Arabidopsis.
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How to cite this article
K. Nadarajah, 2001. The Signalling Pathway Involved in Plant-pathogen Interactions in Arabidopsis thaliana. Pakistan Journal of Biological Sciences, 4: 508-510.
DOI: 10.3923/pjbs.2001.508.510
URL: https://scialert.net/abstract/?doi=pjbs.2001.508.510
DOI: 10.3923/pjbs.2001.508.510
URL: https://scialert.net/abstract/?doi=pjbs.2001.508.510
REFERENCES
- Benedetti, C.E., D. Xie and J.G. Turner, 1995. Coi1 dependent expression of an Arabidopsis vegetative storage protein in flowers and siliques and in response to coronatine or methyl jasmonate. Plant Physiol., 109: 567-572.
Direct Link - Blechert, S., W. Brodschelm, S. Holder, L. Kamerer and T.M. Kutchan, 1995. The octadecanoid pathway signal molecules for the regulation of secondary pathways. Proc. Natl. Acad. Sci. USA., 92: 4099-4105.
Direct Link - Creelman, R.A. and J.E. Mullet, 1997. Biosynthesis and action of jasmonates in plants. Ann. Rev. Plant Physiol. Plant Mol. Biol., 48: 355-381.
CrossRefPubMedDirect Link - Doares, S.H., J.N. Vesquez, A. Conconi and C.A. Ryan, 1995. Salicylic acid inhibition of proteinase inhibitors in tomato leaves induced by systemin and jasmonic acid. Plant Physiol., 108: 1741-1746.
Direct Link - Epple, P., K. Apel and H. Boulman, 1995. An Arabidopsis thaliana thionin gene is inducible via a signal transduction pathway different from that for pathogenesis-related proteins. Plant Physiol., 109: 813-820.
Direct Link - Feys, B.J.F., C.E. Benedetti, C.N. Penfold and J.G. Turner, 1994. Arabidopsis mutants selected for resistance to the phytoalexin coronatine are male sterile insensitive to methyl jasmonate and resistant to bacterial pathogen. Plant Cell, 6: 751-759.
Direct Link - Koiwa, H., R.A. Bressan and P.M. Hasegawa, 1997. Regulation of protease inhibitors and plant defense. Trends Plant Sci., 2: 379-384.
CrossRefDirect Link - McConn, M. and J. Browse, 1996. The critical requirement for linolenic acid in pollen development, not photosynthesis in Arabidopsis mutant. Plant Cell, 8: 403-416.
Direct Link - Somssich, I.E. and K. Halhbrock, 1998. Pathogen defence in plants: a paradigm of biological complexity. Trends Plant Sci., 3: 86-90.
Direct Link - Vijayan, P., J. Shockey, C.A. Levesque, R.J. Cook and J. Browse, 1998. A role for jasmonate in pathogen defence of Arabidopsis. Proc. Natl. Acad. Sci. USA., 95: 7209-7214.
Direct Link