Next Article in Journal
Multifaceted Role of Pneumolysin in the Pathogenesis of Myocardial Injury in Community-Acquired Pneumonia
Next Article in Special Issue
Expressing OsMPK4 Impairs Plant Growth but Enhances the Resistance of Rice to the Striped Stem Borer Chilo suppressalis
Previous Article in Journal
CD147 Promotes CXCL1 Expression and Modulates Liver Fibrogenesis
Previous Article in Special Issue
A Comparison of the Effects of FATTY ACID DESATURASE 7 and HYDROPEROXIDE LYASE on Plant–Aphid Interactions
Article Menu
Issue 4 (April) cover image

Export Article

Open AccessReview
Int. J. Mol. Sci. 2018, 19(4), 1146; https://doi.org/10.3390/ijms19041146

Signals of Systemic Immunity in Plants: Progress and Open Questions

1
Plant Protection Institute, Centre for Agricultural Research, Hungarian Academy of Sciences, 15 Herman Ottó út, H-1022 Budapest, Hungary
2
Phytophthora Research Centre, Department of Forest Protection and Wildlife Management, Faculty of Forestry and Wood Technology, Mendel University in Brno, Zemědělská 3, 613 00 Brno, Czech Republic
*
Author to whom correspondence should be addressed.
Received: 15 February 2018 / Revised: 28 March 2018 / Accepted: 31 March 2018 / Published: 10 April 2018
(This article belongs to the Special Issue Plant Innate Immunity 2.0)
Full-Text   |   PDF [4101 KB, uploaded 3 May 2018]   |  

Abstract

Systemic acquired resistance (SAR) is a defence mechanism that induces protection against a wide range of pathogens in distant, pathogen-free parts of plants after a primary inoculation. Multiple mobile compounds were identified as putative SAR signals or important factors for influencing movement of SAR signalling elements in Arabidopsis and tobacco. These include compounds with very different chemical structures like lipid transfer protein DIR1 (DEFECTIVE IN INDUCED RESISTANCE1), methyl salicylate (MeSA), dehydroabietinal (DA), azelaic acid (AzA), glycerol-3-phosphate dependent factor (G3P) and the lysine catabolite pipecolic acid (Pip). Genetic studies with different SAR-deficient mutants and silenced lines support the idea that some of these compounds (MeSA, DIR1 and G3P) are activated only when SAR is induced in darkness. In addition, although AzA doubled in phloem exudate of tobacco mosaic virus (TMV) infected tobacco leaves, external AzA treatment could not induce resistance neither to viral nor bacterial pathogens, independent of light conditions. Besides light intensity and timing of light exposition after primary inoculation, spectral distribution of light could also influence the SAR induction capacity. Recent data indicated that TMV and CMV (cucumber mosaic virus) infection in tobacco, like bacteria in Arabidopsis, caused massive accumulation of Pip. Treatment of tobacco leaves with Pip in the light, caused a drastic and significant local and systemic decrease in lesion size of TMV infection. Moreover, two very recent papers, added in proof, demonstrated the role of FMO1 (FLAVIN-DEPENDENT-MONOOXYGENASE1) in conversion of Pip to N-hydroxypipecolic acid (NHP). NHP systemically accumulates after microbial attack and acts as a potent inducer of plant immunity to bacterial and oomycete pathogens in Arabidopsis. These results argue for the pivotal role of Pip and NHP as an important signal compound of SAR response in different plants against different pathogens. View Full-Text
Keywords: Arabidopsis; azelaic acid; glycerol-3-phosphate; light dependent signalling; methyl salicylate; N-hydroxypipecolic acid; pipecolic acid; salicylic acid; SAR signalling; spectral distribution of light; tobacco Arabidopsis; azelaic acid; glycerol-3-phosphate; light dependent signalling; methyl salicylate; N-hydroxypipecolic acid; pipecolic acid; salicylic acid; SAR signalling; spectral distribution of light; tobacco
Figures

Graphical abstract

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. (CC BY 4.0).
SciFeed

Share & Cite This Article

MDPI and ACS Style

Ádám, A.L.; Nagy, Z.Á.; Kátay, G.; Mergenthaler, E.; Viczián, O. Signals of Systemic Immunity in Plants: Progress and Open Questions. Int. J. Mol. Sci. 2018, 19, 1146.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics

1

Comments

[Return to top]
Int. J. Mol. Sci. EISSN 1422-0067 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top