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The Plant Immune System: Induction, Memory and De-Priming of Defense

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The Plant Immune System: Induction, Memory and De-Priming of Defense The plant immune system : induction, memory and de-priming of defense responses by endogenous, exogenous and synthetic elicitors Kay Gully To cite this version: Kay Gully. The plant immune system : induction, memory and de-priming of defense responses by endogenous, exogenous and synthetic elicitors. Agricultural sciences. Université d’Angers, 2019. English. NNT : 2019ANGE0001. tel-02419987 HAL Id: tel-02419987 https://tel.archives-ouvertes.fr/tel-02419987 Submitted on 19 Dec 2019 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Table of contents 1. Abbreviations ................................................................................................................... iv 2. Summary ......................................................................................................................... viii 2.1. Résumé en français ......................................................................................................... x 3. General Introduction ......................................................................................................... 1 3.1. MAMPs and DAMPs – defense inducing molecular signatures ...................................... 2 3.2. Phytocytokines and small endogenous signaling peptides ............................................ 7 3.3. Plant innate immunity .................................................................................................. 11 3.4. Defense responses induced during PTI ......................................................................... 15 3.5. Systemic acquired resistance (SAR) .............................................................................. 20 3.6. Defense priming – The third layer of defense? ............................................................ 24 3.7. Antisense transcription ................................................................................................. 32 3.8. The aims of this thesis. .................................................................................................. 33 4. The SCOOP12 peptide regulates defense responses and root development in Arabidopsis thaliana. .............................................................................................................. 35 4.1. Abstract ......................................................................................................................... 35 4.2. Introduction .................................................................................................................. 36 4.3. Results ........................................................................................................................... 38 4.4. Discussion ...................................................................................................................... 55 4.5. Material and methods .................................................................................................. 57 5. The SCOOP family contains several defense-response inducing peptides that can regulate root growth ............................................................................................................... 61 i 5.1. Abstract ......................................................................................................................... 61 5.2. Introduction .................................................................................................................. 62 5.3. Results ........................................................................................................................... 63 5.4. Discussion ...................................................................................................................... 70 5.5. Material and methods .................................................................................................. 74 5.6. Appendix: Are PROSCOOP genes under epigenetic control? ....................................... 77 6. Biotic stress-induced priming and de-priming of transcriptional memory in Arabidopsis and apple ................................................................................................................................. 81 6.1. Abstract ......................................................................................................................... 82 6.2. Introduction .................................................................................................................. 82 6.3. Results ........................................................................................................................... 85 6.4. Discussion ...................................................................................................................... 98 6.5. Material and methods ................................................................................................ 102 6.6. Appendix: Does BTH/flg22 application influence defense responses and Pseudomonas resistance in a long-time memory fashion? ...................................................................... 106 7. General Discussion ........................................................................................................ 111 7.1. The discovery of the SCOOP peptide family ............................................................... 111 7.2. Possible posttranscriptional modifications of the SCOOP family ............................... 112 7.3. The identification of the SCOOP receptor(s) – the next big challenge ....................... 113 7.4. Phytocytokines – peptides between defense and development ............................... 114 7.5. DAMPs and synthetic elicitors as plant defense stimulating compounds .................. 116 7.6. Is a plant able to forget? ............................................................................................. 118 7.7. Molecular mechanism of de-priming.......................................................................... 120 7.8. Conclusion ................................................................................................................... 122 7.9. Outlook ....................................................................................................................... 124 ii 8. Acknowledgements ....................................................................................................... 127 9. References ..................................................................................................................... 128 10. Appendix: Scientific publication (Gully et.al., 2018 Journal of experimental botany) . .................................................................................................................................... 154 11. Curriculum Vitae ........................................................................................................ 195 iii 1. Abbreviations aa Amino acid ABA Abscisic acid ASM Acibenzolar-S-methyl ester (commercialized as Bion) (see also BTH) BA benzyl adenine, a cytokinin for growth media BABA Beta-aminobutyric acid BAK1 BRI1 associated kinase 1 BIK1 BOTRYTIS-INDUCED KINASE1 BTH Benzothiadiazole (commercialized as Bion) bZIP Basic leucin zipper transcription factors CD2-1 C-terminal epitope of flagellin cDNA Complementing DNA CDPK Calcium-dependent protein kinase CEP1 C-TERMINAL ENCODED PEPTIDE 1 CERK1 Chitin elicitor receptor kinase 1 cfu Colony forming units CLE CLAVATA3/EMBRYO-SURROUNDING REGION COI1 Coronatine-insensitive 1 Col-0 Columbia-0 Ecotype CRP Cysteine-Rich Peptide dag Days after germination DAMPs Damage/danger associated molecular pattern dap Days after propagation DDM1 DECREASE IN DNA METHYLATION 1 DET Differently expressed transcripts DORN1 DOES NOT RESPOND TO NUCLEOTIDES 1 DRM DOMAINS REARRANGED METHYLTRANSFERASE dsRNA Double stranded RNA eATP Extracellular ATP eDNA Extracellular DNA EFR Elongation factor Tu receptor iv EF-Tu Elongation factor thermo unstable EGF Epidermal growth factor elf18/26 18/26 amino acids peptide of the N-terminus of EF-Tu ETI Effector triggered immunity ETS Effector-triggered susceptibility FER Feronia , RALF receptor FLC FLOWERING LOCUS C flg22 22 amino acids peptide of the N-terminus of flagellin FLS2 Flagellin sensing 2 FRK1 Flagellin responsive kinase 1 GLV Green-leaf volatiles gRNA Guide RNA H3ac Histone 3 acetylation H3K4me2 Histone 4 lysine 4 di-methylation H3K4me3 Histone 4 lysine 4 tri-methylation H3K9ac Histone 3 lysin 9 acetylation H4ac Histone 4 acetylation HAC1 Histone acetyltransferase 1 HR Hypersensitive response HypSys Hydroxyproline-containing glycopeptides IBA Indole-3-butyric acid, auxin used for growth media INA 2,6-dichloro-isonicotinic acid ISR Induced systemic resistance JA Jasmonic acid JA-Ile Jasmonoyl-Isoleucine LPS Lipopolysaccharides LRR Leucin rich repeat LysM Lysine motif MAMP Microbe associated molecular pattern MAPK Mitogen-Activated Protein Kinase MET1 METHYLTRANSFERASE1 miRNA MicroRNA MOM1 MORPHEUS´MOLECULE 1 v mRNA Messenger RNA MS Murashige & Skoog Medium MTI Microbe triggered immunity NADPH Nicotinamidadenine Dinucleotidephosphate NPR1 NON-EXPRESSOR OF
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