在病原菌誘發植物先天性免疫反應中，許多MAPK路徑之調控已被證實參與在其中，然而對於其下游影響之路徑有許多仍屬未知，此外，不同之病原菌相關分子 ( pathogen-associated molecular pattern, PAMP ) 及效應蛋白 ( effector protein ) 雖可以誘導同樣之PTI ( PAMP-triggered immunity ) 及ETI ( effector-triggered immunity ) 免疫反應，但各個免疫反應下游調控之基因亦可能不同。近年來已有許多研究證實細菌可藉由分泌細菌揮發物影響植物之生長與發育，為了解細菌揮發化合物誘導植物免疫反應之防禦情形， 本研究利用實驗室先前篩出的植物生長抑制菌 Enterobacter aerogenes 所分泌的揮發性化合物C2來處理阿拉伯芥，並觀察其所誘導的免疫反應。透過利用即時聚合酶鏈鎖反應 ( Real-time polymerase chain reaction, qPCR )，了解先天性免疫誘發、防禦性賀爾蒙乙烯及茉莉酸之訊息傳遞路徑與植物防禦素 camalexin 生合成路徑之相關基因的表現量，並且觀察處理 C2 後氣孔開閉情形與胝質降解反應，來了解 C2 對於植物產生免疫反應的影響。且經mkk3突變株相關實驗，發現到AtMKK3可能參與阿拉伯芥受到C2揮發性化合物誘導camalexin生合成的途徑。本研究的結果可以幫助我們對於微生物影響植物生長有更深入的了解，也利於為來進行相關的農業應用。

Recent studies have identified several MAPK cascades involved in plant innate immunity regulation. However, the downstream signaling pathway of MAPK cascades still needs to be elucidated. Even though different pathogens and pathgen derived elicitors can trigger similar PTI and ETI, the downstream regulation components might be different. It has been proved that bacteria will affect plant growth by emitting volatile compounds (VCs). To investigate the bacterial effects on plant innate immunity, plants was treated by C2 compound, which was extracted from Enterobacter aerogenes , and it could inhibit the growth in Arabidopsis thaliana Col-0. By analyzing the expression level of innate immunity related genes, ethylene signaling related genes, Jasmonic acid signaling related genes and camalexin biosynthesis related genes, we found that C2 compound could not only trigger the Arabidopsis innate immunity but also involve in Jasmonic acid and ethylene signaling pathway. In addition, there are complex regulation network under C2 stress through stomatal aperture. We also found that Arabidopsis might regulate camalexin biosynthesis by MKK3-dependent signaling pathway when under C2 stress. However, C2 compound can trigger callose deposition in MKK3-independent pattern.

Alstrom, S. and Burns, R.G. Cyanide production by rhizobacteria as a possible mechanism of plant growth inhibition. Biology and Fertility of Soils, 7, 232-238 (1989)
Ausubel, F.M., Katagiri, F., Mindrinos, M., and Glazebrook, J. Use of Arabidopsis thaliana defense-related mutants to dissect the plant-response to pathogens. Proc. Natl. Acad. Sci. U.S.A., 92, 4189-4196 (1995)
Brown, I., Trethowan, J., Kerry, M., Mansfield, J., and Bolwell, G.P. Localization of components of the oxidative cross-linking of glycopro- teins and of callose synthesis in papillae formed during the interaction between non-pathogenic strains of Xanthomonas campestris and French bean mesophyll cells. Plant J., 15, 333-343. (1998)
Asai, T., Tena, G., Plotnikova, J., Willmann, M.R., Chiu, W.L., Gomez-Gomez, L., Boller, T., Ausubel, F.M., Sheen, J. MAP kinase signalling cascade in Arabidopsis innate immunity. Nature, 415, 977-983 (2002)
Bednarek, P., Kwon, C., Schulze-Lefert, P. Not a peripheral issue: secretion in plant-microbe interactions. Curr. Opin. Plant Biol., 13, 378-387 (2010)
Blom, D., Fabbri, C., Eberl, L., Weisskopf, L. Volatile-mediated killing of Arabidopsis thaliana by bacteria is mainly due to hydrogen cyanide. Appl Environ Microbiol, 77, 1000-1008 (2011)
Bethke, G., Pecher, P., Eschen-Lippold, L., Tsuda, K., Katagiri, F., Glazebrook, J., Scheel, D., and Lee, J. Activation of the Arabidopsis thaliana mitogen-activated protein kinase MPK11 by the flagellin-derived elicitor peptide, flg22. Mol. Plant Microbe Interact, 25, 471-480 (2012)
Colcombet, J. and Hirt, H. Arabidopsis MAPKs: a complex signalling network involved in multiple biological processes. Biochem. J., 413, 217-226. (2008)
Clay, N.K., Adio, A.M., Denoux, C., Jander, G., Ausubel, F.M. Glucosinolate Metabolites Required for an Arabidopsis Innate Immune Response. Science, 323, 95-100 (2009)
Carvalho Ade, O., Gomes, V.M. Plant defensins—Prospects for the biological functions and biotechnological properties. Peptides, 30, 1007-1020. (2009)
Carvalho Ade, O., Gomes, V.M. Plant defensins and defensin-like peptides—Biological activities and biotechnological applications. Curr. Pharm. Des., 17, 4270-4293 (2011)
De Coninck, B., Cammue, B.P.A., Thevissen, K. Modes of antifungal action and in planta functions of plant defensins and defensin-like peptides. Fungal Biol. Rev., 26, 109-120 (2013)
DebRoy, S., Thilmony, R., Kwack, Y.B., Nomura, K., He, S.Y. A family of conserved bacterial effectors inhibits salicylic acid-mediated basal immunity and promotes disease necrosis in plants. PNAS, 101, 9927-9932 (2004)
Doczi, R., Brader, G., Pettko-Szandtner, A., Rajh, I., Djamei, A., Pitzschke, A., Teige, M., Hirt, H. The Arabidopsis mitogen-activated protein kinase kinase MKK3 is upstream of group C mitogen-activated protein kinases and participates in pathogen signaling. Plant Cell, 19, 3266-3279 (2007)
Denoux, C., Galletti, R., Mammarella, N., Gopalan, S., Werck, D., De Lorenzo, G., Ferrari, S., Ausubel, F.M., Dewdney, J. Activation of defense response pathways by OGs and Flg22 elicitors in Arabidopsis seedlings. Mol Plant, 1, 423-445 (2008)
Dodds, P.N., Rathjen, J.P., Plant immunity: towards an integrated view of plant-pathogen interactions. Nat Rev Genet, 11, 539-548 (2010)
Gomez-Gomez, L., Felix, G., and Boller, T. A single locus deter- mines sensitivity to bacterial flagellin in Arabidopsis thaliana. Plant J., 18, 277-284 (1999a)
Hanks, J.N., Snyder, A.K., Graham, M.A., Shah, R.K., Blaylock, L.A., Harrison, M.J., Shah, D.M. Defensin gene family in Medicago truncatula: Structure, expression and induction by signal molecules. Plant Mol. Biol., 58, 385-399 (2005)
Hiruma, K., Nishiuchi, T., Kato, T., Bednarek, P., Okuno, T., Schulze-Lefert, P., Takano, Y. Arabidopsis ENHANCED DISEASE RESISTANCE 1 is required for pathogen-induced expression of plant defensins in nonhost resistance, and acts through interference of MYC2-mediated repressor function. Plant J, 67, 980-992 (2011)
Ichimura, K., Shinozaki, K., Tena, G., Sheen, J., Henry, Y., Champion, A., Kreis, M., Zhang, S., Hirt, H., Wilson, C., Heberle-Bors, E., Ellis, B. E., Morris, P.C., Innes, R.W., Ecker, J.R., Scheel, D., Klessig, D.F., Machida, Y., Mundy, J., Ohashi, Y., and Walker, J.C. Mitogen-activated protein kinase cascades in plants: a new nomenclature. Trends Plant Sci., 7, 301-308 (2002)
Inamdar, A.A., Masurekar, P., Bennett, J.W., Neurotoxicity of fungal volatile organic compounds in Drosophila melanogaster. Toxicol Sci, 117, 418-426. (2010)
Inamdar, A.A., Zaman, T., Morath, S.U., Pu, D.C., Bennett, J.W. Drosophila melanogaster as a model to characterize fungal volatile organic compounds. Environ Toxicol, 29, 829-836 (2014)
Kai, M., Haustein, M., Molina, F., Petri, A., Scholz, B. and Piechulla, B. Bacterial volatiles and their action potential. Applied Microbiology and Biotechnology, 81, 1001-1012 (2008)
Korpi, A., Jarnberg, J., Pasanen, A.L., Microbial volatile organic compounds. Crit Rev Toxicol, 39, 139-193 (2009)
Leon, J., Rojo, E., and Sanchez-Serrano, J.J. Wound signalling in plants. J. Exp. Bot., 52, 1-9 (2001)
Luna, E., Pastor, V., Robert, J., Flors, V., Mauch-Mani, B., Ton, J. Callose Deposition: A Multifaceted Plant Defense Response. Molecular Plant-Microbe Interactions, 24, 183-193 (2011)
Maitra, N., Cushman, J.C. lsolation and Characterization of a Drought-lnduced Soybean cDNA Encoding a D95 Family late-Embryogenesis-Abundant Protein. Plant Physiol, 106, 805-806 (1994)
Manners, J.M., Penninckx, I.A., Vermaere, K., Kazan, K., Brown, R.L., Morgan, A., Maclean, D.J., Curtis, M.D., Cammue, B.P., Broekaert, W.F. The promoter of the plant defensin gene PDF1.2 from Arabidopsis is systemically activated by fungal pathogens and responds to methyl jasmonate but not to salicylic acid. Plant Mol. Biol., 38, 1071-1080 (1998)
Melotto, M., Underwood, W., Koczan, J., Nomura, K., He, S.Y. Plant stomata function in innate immunity against bacterial invasion. Cell, 126, 969-980 (2006)
Mao, G., Meng, X., Liu, Y., Zheng, Z., Chen, Z. and Zhang, S. Phosphorylation of a WRKY Transcription Factor by Two Pathogen-Responsive MAPKs Drives Phytoalexin Biosynthesis in Arabidopsis. Plant Cell, 23, 1639- 1653 (2011)
Nafisi, M., Goregaoker, S., Botanga, C. J., Glawischnig, E., Olsen, C. E., Halkier, B. A., and Glazebrook, J. Arabidopsis cytochrome P450 monooxygenase 71A13 catalyzes the conversion of indole-3- acetaldoxime in camalexin synthesis. Plant Cell, 19, 2039-2052. (2007)
Petersen, M., Brodersen, P., Naested, H., Andreasson, E., Lindhart, U., Johansen, B., Nielsen, H. B., Lacy, M., Austin, M. J., Parker, J. E., Sharma, S. B., Klessig, D. F., Mar- tienssen, R., Mattsson, O., Jensen, A. B., and Mundy, J. Arabidopsis MAP kinase 4 negatively regulates systemic acquired resistance. Cell, 103, 1111-1120 (2000)
Rasmussen, M.W., Roux, M., Petersen, M., Mundy, J. MAP Kinase Cascades in Arabidopsis Innate Immunity. Front Plant Sci, 3, 169 (2012)
Saga, H., Ogawa, T., Kai, K., Suzuki, H., Ogata, Y., Sakurai, N., Shibata, D., Ohta, D. Identification and Characterization of ANAC042, a Transcription Factor Family Gene Involved in the Regulation of Camalexin Biosynthesis in Arabidopsis. Molecular Plant-Microbe Interactions, 25, 684-696 (2012)
Takahashi, F., Yoshida, R., Ichimura, K., Mizoguchi, T., Seo, S., Yonezawa, M., Maruyama, K., Yamaguchi-Shinozaki, K., Shinozaki, K. The mitogen-activated protein kinase cascade MKK3-MPK6 is an important part of the jasmonate signal transduction pathway in Arabidopsis. Plant Cell, 19, 805-818 (2007)
Ton, J., Flors, V., Mauch-Mani, B. The multifaceted role of ABA in disease resistance. Trends Plant Sci, 14, 310-317 (2009)
Taj, G., Agarwal, P., Grant, M., and Kumar, A. MAPK machinery in plants: Recognition and respose to different stresses through multiple signal trsansduction pathways. Plant Signaling & Behavior, 5, 1370-1378 (2010)
Tena, G., Boudsocq, M. and Sheen, J. Protein kinase signaling networks in plant innate immunity. Curr. Opin. Plant Biol., 14, 519-529 (2011)
Tahir, H.A., Gu, Q., Wu, H., Raza, W., Hanif, A., Wu, L., Colman, M.V., Gao, X. Plant Growth Promotion by Volatile Organic Compounds Produced by Bacillus subtilis SYST2. Front Microbiol, 8, 171 (2017)
Vespermann, A., Kai, M. and Piechulla, B. Rhizobacterial Volatiles affect the growth of fungi and Arabidopsis thaliana. Applied and Environmental Microbiology, 73, 5639-5641 (2007)
Wenke, K., Wanke, D., Kilian, J., Berendzen, K., Harter, K., Piechulla, B. Volatiles of two growth-inhibiting rhizobacteria commonly engage AtWRKY18 function. Plant J, 70, 445-459 (2012)
Xu, J., Meng, J., Meng, X., Zhao, Y., Liu, J., Sun, T., Liu, Y., Wang, Q., Zhang, S. Pathogen-Responsive MPK3 and MPK6 Reprogram the Biosynthesis of Indole Glucosinolates and Their Derivatives in Arabidopsis Immunity. Plant Cell, 28, 1144-1162 (2016)
Yang, J., Kloepper, J.W., Ryu, C.M. Rhizosphere bacteria help plants tolerate abiotic stress. Trends Plant Sci, 14, 1-4 (2009)
Zhou, N., Tootle, T. L., and Glaze-brook, J. Arabidopsis PAD3, a gene required for camalexin biosynthesis, encodes a putative cytochrome P450 monooxygenase. Plant Cell, 11, 2419-2428 (1999)
Zheng, Z., Qamar, S. A., Chen, Z., and Mengiste, T. Arabidopsis WRKY33 transcription factor is required for resistance to necrotrophic fungal pathogens. Plant J., 48, 592-605 (2006)
Zeng, W., Melotto, M., He, S.Y. Plant stomata: a checkpoint of host immunity and pathogen virulence. Curr Opin Biotechnol, 21, 599-603. (2010)
Zou, C., Li, Z., and Yu, D. Bacillus megaterium strain XTBG34 promotes plant growth by producing 2-pentylfuran. J. Microbiol., 48, 460-466. (2010)
Zhang, Z., Wu, Y., Gao, M., Zhang, J., Kong, Q., Liu, Y., Ba, H., Zhou, J., and Zhang, Y. Disruption of PAMP-induced MAP kinase cascade by a Pseudomonas syringae effector activates plant immunity mediated by the NB-LRR protein SUMM2. Cell Host Microbe, 11, 253-263 (2012)