Autoimmunity conferred by chs3-2D relies on CSA1, its adjacent TIR-NB-LRR encoding neighbour

Plant innate immunity depends on the function of a large number of intracellular immune receptor proteins, the majority of which are structurally similar to mammalian nucleotidebinding oligomerization domain (NOD)-like receptor (NLR) proteins. CHILLING SENSITIVE 3 (CHS3) encodes an atypical Toll/Interleukin 1 Receptor (TIR)-type NLR protein with an additional Lin-11, Isl-1 and Mec-3 (LIM) domain at its C-terminus. The gain-of-function mutant allele chs3-2D exhibits severe dwarfism and constitutively activated defense responses, including enhanced resistance to virulent pathogens, high defence marker gene expression, and salicylic acid accumulation. To search for novel regulators involved in CHS3-mediated immune signaling, we conducted suppressor screens in the chs3-2D and chs3-2D pad4-1 genetic backgrounds. Alleles of sag101 and eds1-90 were isolated as complete suppressors of chs3-2D, and alleles of sgt1b were isolated as partial suppressors of chs3-2D pad4-1. These mutants suggest that SAG101, EDS1-90, and SGT1b are all positive regulators of CHS3-mediated defense signaling. Additionally, the TIR-type NLR-encoding CSA1 locus located genomically adjacent to CHS3 was found to be fully required for chs3-2D-mediated autoimmunity. CSA1 is located 3.9kb upstream of CHS3 and is transcribed in the opposite direction. Altogether, these data illustrate the distinct genetic requirements for CHS3-mediated defense signaling

Allele-Specific Virulence Attenuation of the Pseudomonas syringae HopZ1a Type III Effector via the Arabidopsis ZAR1 Resistance Protein

Plant resistance (R) proteins provide a robust surveillance system to defend against potential pathogens. Despite their importance in plant innate immunity, relatively few of the ∼170 R proteins in Arabidopsis have well-characterized resistance specificity. In order to identify the R protein responsible for recognition of the Pseudomonas syringae type III secreted effector (T3SE) HopZ1a, we assembled an Arabidopsis R gene T–DNA Insertion Collection (ARTIC) from publicly available Arabidopsis thaliana insertion lines and screened it for plants lacking HopZ1a-induced immunity. This reverse genetic screen revealed that the Arabidopsis R protein HOPZ-ACTIVATED RESISTANCE 1 (ZAR1; At3g50950) is required for recognition of HopZ1a in Arabidopsis. ZAR1 belongs to the coiled-coil (CC) class of nucleotide binding site and leucine-rich repeat (NBS–LRR) containing R proteins; however, the ZAR1 CC domain phylogenetically clusters in a clade distinct from other related Arabidopsis R proteins. ZAR1–mediated immunity is independent of several genes required by other R protein signaling pathways, including NDR1 and RAR1, suggesting that ZAR1 possesses distinct signaling requirements. The closely-related T3SE protein, HopZ1b, is still recognized by zar1 Arabidopsis plants indicating that Arabidopsis has evolved at least two independent R proteins to recognize the HopZ T3SE family. Also, in Arabidopsis zar1 plants HopZ1a promotes P. syringae growth indicative of an ancestral virulence function for this T3SE prior to the evolution of recognition by the host resistance protein ZAR1. Our results demonstrate that the Arabidopsis resistance protein ZAR1 confers allele-specific recognition and virulence attenuation of the Pseudomonas syringae T3SE protein HopZ1a

Identification, characterization, and gene expression analysis of nucleotide binding site (NB)-type resistance gene homologues in switchgrass

Abstract Background Switchgrass (Panicum virgatum L.) is a warm-season perennial grass that can be used as a second generation bioenergy crop. However, foliar fungal pathogens, like switchgrass rust, have the potential to significantly reduce switchgrass biomass yield. Despite its importance as a prominent bioenergy crop, a genome-wide comprehensive analysis of NB-LRR disease resistance genes has yet to be performed in switchgrass. Results In this study, we used a homology-based computational approach to identify 1011 potential NB-LRR resistance gene homologs (RGHs) in the switchgrass genome (v 1.1). In addition, we identified 40 RGHs that potentially contain unique domains including major sperm protein domain, jacalin-like binding domain, calmodulin-like binding, and thioredoxin. RNA-sequencing analysis of leaf tissue from ‘Alamo’, a rust-resistant switchgrass cultivar, and ‘Dacotah’, a rust-susceptible switchgrass cultivar, identified 2634 high quality variants in the RGHs between the two cultivars. RNA-sequencing data from field-grown cultivar ‘Summer’ plants indicated that the expression of some of these RGHs was developmentally regulated. Conclusions Our results provide useful insight into the molecular structure, distribution, and expression patterns of members of the NB-LRR gene family in switchgrass. These results also provide a foundation for future work aimed at elucidating the molecular mechanisms underlying disease resistance in this important bioenergy crop

Towards Establishment of a Rice Stress Response Interactome

Rice (Oryza sativa) is a staple food for more than half the world and a model for studies of monocotyledonous species, which include cereal crops and candidate bioenergy grasses. A major limitation of crop production is imposed by a suite of abiotic and biotic stresses resulting in 30%–60% yield losses globally each year. To elucidate stress response signaling networks, we constructed an interactome of 100 proteins by yeast two-hybrid (Y2H) assays around key regulators of the rice biotic and abiotic stress responses. We validated the interactome using protein–protein interaction (PPI) assays, co-expression of transcripts, and phenotypic analyses. Using this interactome-guided prediction and phenotype validation, we identified ten novel regulators of stress tolerance, including two from protein classes not previously known to function in stress responses. Several lines of evidence support cross-talk between biotic and abiotic stress responses. The combination of focused interactome and systems analyses described here represents significant progress toward elucidating the molecular basis of traits of agronomic importance

Distinct colonization patterns and cDNA-AFLP transcriptome profiles in compatible and incompatible interactions between melon and different races of Fusarium oxysporum f. sp. melonis

Background: Fusarium oxysporum f. sp. melonis Snyd. & Hans. (FOM) causes Fusarium wilt, the most important infectious disease of melon (Cucumis melo L.). The four known races of this pathogen can be distinguished only by infection on appropriate cultivars. No molecular tools are available that can discriminate among the races, and the molecular basis of compatibility and disease progression are poorly understood. Resistance to races 1 and 2 is controlled by a single dominant gene, whereas only partial polygenic resistance to race 1,2 has been described. We carried out a large-scale cDNA-AFLP analysis to identify host genes potentially related to resistance and susceptibility as well as fungal genes associated with the infection process. At the same time, a systematic reisolation procedure on infected stems allowed us to monitor fungal colonization in compatible and incompatible host-pathogen combinations. Results: Melon plants (cv. Charentais Fom-2), which are susceptible to race 1,2 and resistant to race 1, were artificially infected with a race 1 strain of FOM or one of two race 1,2 w strains. Host colonization of stems was assessed at 1, 2, 4, 8, 14, 16, 18 and 21 days post inoculation (dpi), and the fungus was reisolated from infected plants. Markedly different colonization patterns were observed in compatible and incompatible host-pathogen combinations. Five time points from the symptomless early stage (2 dpi) to obvious wilting symptoms (21 dpi) were considered for cDNA-AFLP analysis. After successful sequencing of 627 transcript-derived fragments (TDFs) differentially expressed in infected plants, homology searching retrieved 305 melon transcripts, 195 FOM transcripts expressed in planta and 127 orphan TDFs. RNA samples from FOM colonies of the three strains grown in vitro were also included in the analysis to facilitate the detection of in planta-specific transcripts and to identify TDFs differentially expressed among races/strains. Conclusion: Our data suggest that resistance against FOM in melon involves only limited transcriptional changes, and that wilting symptoms could derive, at least partially, from an active plant response. We discuss the pathogen-derived transcripts expressed in planta during the infection process and potentially related to virulence functions, as well as transcripts that are differentially expressed between the two FOM races grown in vitro. These transcripts provide candidate sequences that can be further tested for their ability to distinguish between races. Sequence data from this article have been deposited in GenBank, Accession Numbers: HO867279-HO867981

A Secretory Protein of Necrotrophic Fungus Sclerotinia sclerotiorum That Suppresses Host Resistance

SSITL (SS1G_14133) of Sclerotinia sclerotiorum encodes a protein with 302 amino acid residues including a signal peptide, its secretion property was confirmed with immunolocalization and immunofluorescence techniques. SSITL was classified in the integrin alpha N-terminal domain superfamily, and its 3D structure is similar to those of human integrin α4-subunit and a fungal integrin-like protein. When S. sclerotiorum was inoculated to its host, high expression of SSITL was detected during the initial stages of infection (1.5-3.0 hpi). Targeted silencing of SSITL resulted in a significant reduction in virulence; on the other hand, inoculation of SSITL silenced transformant A10 initiated strong and rapid defense response in Arabidopsis, the highest expressions of defense genes PDF1.2 and PR-1 appeared at 3 hpi which was 9 hr earlier than that time when plants were inoculated with the wild-type strain of S. sclerotiorum. Systemic resistance induced by A10 was detected by analysis of the expression of PDF1.2 and PR-1, and confirmed following inoculation with Botrytis cinerea. A10 induced much larger lesions on Arabidopsis mutant ein2 and jar1, and slightly larger lesions on mutant pad4 and NahG in comparison with the wild-type plants. Furthermore, both transient and constitutive expression of SSITL in Arabidopsis suppressed the expression of PDF1.2 and led to be more susceptible to A10 and the wild-type strain of S. sclerotiorum and B. cinerea. Our results suggested that SSITL is an effector possibly and plays significant role in the suppression of jasmonic/ethylene (JA/ET) signal pathway mediated resistance at the early stage of infection

An allele of Arabidopsis COI1 with hypo- and hypermorphic phenotypes in plant growth, defence and fertility

Resistance to biotrophic pathogens is largely dependent on the hormone salicylic acid (SA) while jasmonic acid (JA) regulates resistance against necrotrophs. JA negatively regulates SA and is, in itself, negatively regulated by SA. A key component of the JA signal transduction pathway is its receptor, the COI1 gene. Mutations in this gene can affect all the JA phenotypes, whereas mutations in other genes, either in JA signal transduction or in JA biosynthesis, lack this general effect. To identify components of the part of the resistance against biotrophs independent of SA, a mutagenised population of NahG plants (severely depleted of SA) was screened for suppression of susceptibility. The screen resulted in the identification of intragenic and extragenic suppressors, and the results presented here correspond to the characterization of one extragenic suppressor, coi1-40. coi1-40 is quite different from previously described coi1 alleles, and it represents a strategy for enhancing resistance to biotrophs with low levels of SA, likely suppressing NahG by increasing the perception to the remaining SA. The phenotypes of coi1-40 lead us to speculate about a modular function for COI1, since we have recovered a mutation in COI1 which has a number of JA-related phenotypes reduced while others are equal to or above wild type levels.This work was supported by grant BIO201018896 from "Ministerio de Economia y Competitividad" (MINECO) of Spain and by grant ACOMP/2012/105 from "Generalitat Valenciana" to PT, a JAE-CSIC Fellowship to JVC, a FPI-MINECO to AD, and Fellowships from the European Molecular Biology Organization and the Human Frontier Science Program to BBHW. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Dobón Alonso, A.; Wulff, BBH.; Canet Perez, JV.; Fort Rausell, P.; Tornero Feliciano, P. (2013). An allele of Arabidopsis COI1 with hypo- and hypermorphic phenotypes in plant growth, defence and fertility. PLoS ONE. 1(8):55115-55115. https://doi.org/10.1371/journal.pone.0055115S551155511518Vlot, A. C., Dempsey, D. A., & Klessig, D. F. (2009). Salicylic Acid, a Multifaceted Hormone to Combat Disease. Annual Review of Phytopathology, 47(1), 177-206. doi:10.1146/annurev.phyto.050908.135202Mauch, F., Mauch-Mani, B., Gaille, C., Kull, B., Haas, D., & Reimmann, C. (2001). Manipulation of salicylate content in Arabidopsis thaliana by the expression of an engineered bacterial salicylate synthase. The Plant Journal, 25(1), 67-77. doi:10.1046/j.1365-313x.2001.00940.xGaffney, T., Friedrich, L., Vernooij, B., Negrotto, D., Nye, G., Uknes, S., … Ryals, J. (1993). Requirement of Salicylic Acid for the Induction of Systemic Acquired Resistance. Science, 261(5122), 754-756. doi:10.1126/science.261.5122.754Delaney, T. P., Uknes, S., Vernooij, B., Friedrich, L., Weymann, K., Negrotto, D., … Ryals, J. (1994). A Central Role of Salicylic Acid in Plant Disease Resistance. Science, 266(5188), 1247-1250. doi:10.1126/science.266.5188.1247Lawton, K. (1995). Systemic Acquired Resistance inArabidopsisRequires Salicylic Acid but Not Ethylene. Molecular Plant-Microbe Interactions, 8(6), 863. doi:10.1094/mpmi-8-0863Ross, A. F. (1961). Systemic acquired resistance induced by localized virus infections in plants. Virology, 14(3), 340-358. doi:10.1016/0042-6822(61)90319-1Pieterse, C. M. ., & van Loon, L. C. (1999). Salicylic acid-independent plant defence pathways. Trends in Plant Science, 4(2), 52-58. doi:10.1016/s1360-1385(98)01364-8Fonseca, S., Chico, J. M., & Solano, R. (2009). The jasmonate pathway: the ligand, the receptor and the core signalling module. Current Opinion in Plant Biology, 12(5), 539-547. doi:10.1016/j.pbi.2009.07.013Ton, J., De Vos, M., Robben, C., Buchala, A., Métraux, J.-P., Van Loon, L. C., & Pieterse, C. M. J. (2002). Characterization ofArabidopsisenhanced disease susceptibility mutants that are affected in systemically induced resistance. The Plant Journal, 29(1), 11-21. doi:10.1046/j.1365-313x.2002.01190.xCui, J., Bahrami, A. K., Pringle, E. G., Hernandez-Guzman, G., Bender, C. L., Pierce, N. E., & Ausubel, F. M. (2005). Pseudomonas syringae manipulates systemic plant defenses against pathogens and herbivores. Proceedings of the National Academy of Sciences, 102(5), 1791-1796. doi:10.1073/pnas.0409450102Robert-Seilaniantz, A., Navarro, L., Bari, R., & Jones, J. D. (2007). Pathological hormone imbalances. Current Opinion in Plant Biology, 10(4), 372-379. doi:10.1016/j.pbi.2007.06.003Garcion, C., Lohmann, A., Lamodière, E., Catinot, J., Buchala, A., Doermann, P., & Métraux, J.-P. (2008). Characterization and Biological Function of the ISOCHORISMATE SYNTHASE2 Gene of Arabidopsis. Plant Physiology, 147(3), 1279-1287. doi:10.1104/pp.108.119420Tornero, P., Chao, R. A., Luthin, W. N., Goff, S. A., & Dangl, J. L. (2002). Large-Scale Structure –Function Analysis of the Arabidopsis RPM1 Disease Resistance Protein. The Plant Cell, 14(2), 435-450. doi:10.1105/tpc.010393Bowling, S. A., Guo, A., Cao, H., Gordon, A. S., Klessig, D. F., & Dong, X. (1994). A mutation in Arabidopsis that leads to constitutive expression of systemic acquired resistance. The Plant Cell, 6(12), 1845-1857. doi:10.1105/tpc.6.12.1845Bowling, S. A., Clarke, J. D., Liu, Y., Klessig, D. F., & Dong, X. (1997). The cpr5 mutant of Arabidopsis expresses both NPR1-dependent and NPR1-independent resistance. The Plant Cell, 9(9), 1573-1584. doi:10.1105/tpc.9.9.1573Yu, I. -c., Parker, J., & Bent, A. F. (1998). Gene-for-gene disease resistance without the hypersensitive response in Arabidopsis dnd1 mutant. Proceedings of the National Academy of Sciences, 95(13), 7819-7824. doi:10.1073/pnas.95.13.7819Dietrich, R. A., Delaney, T. P., Uknes, S. J., Ward, E. R., Ryals, J. A., & Dangl, J. L. (1994). Arabidopsis mutants simulating disease resistance response. Cell, 77(4), 565-577. doi:10.1016/0092-8674(94)90218-6Rivas-San Vicente, M., & Plasencia, J. (2011). Salicylic acid beyond defence: its role in plant growth and development. Journal of Experimental Botany, 62(10), 3321-3338. doi:10.1093/jxb/err031Wang, D. (2005). Induction of Protein Secretory Pathway Is Required for Systemic Acquired Resistance. Science, 308(5724), 1036-1040. doi:10.1126/science.1108791Ritter, C. (1995). TheavrRpm1Gene ofPseudomonas syringaepv.maculicolaIs Required for Virulence on Arabidopsis. Molecular Plant-Microbe Interactions, 8(3), 444. doi:10.1094/mpmi-8-0444Debener, T., Lehnackers, H., Arnold, M., & Dangl, J. L. (1991). Identification and molecular mapping of a single Arabidopsis thaliana locus determining resistance to a phytopathogenic Pseudomonas syringae isolate. The Plant Journal, 1(3), 289-302. doi:10.1046/j.1365-313x.1991.t01-7-00999.xGrant, M., Godiard, L., Straube, E., Ashfield, T., Lewald, J., Sattler, A., … Dangl, J. (1995). Structure of the Arabidopsis RPM1 gene enabling dual specificity disease resistance. Science, 269(5225), 843-846. doi:10.1126/science.7638602Mindrinos, M., Katagiri, F., Yu, G.-L., & Ausubel, F. M. (1994). The A. thaliana disease resistance gene RPS2 encodes a protein containing a nucleotide-binding site and leucine-rich repeats. Cell, 78(6), 1089-1099. doi:10.1016/0092-8674(94)90282-8Coego, A., Ramirez, V., Gil, M. J., Flors, V., Mauch-Mani, B., & Vera, P. (2005). An Arabidopsis Homeodomain Transcription Factor, OVEREXPRESSOR OF CATIONIC PEROXIDASE 3, Mediates Resistance to Infection by Necrotrophic Pathogens. The Plant Cell, 17(7), 2123-2137. doi:10.1105/tpc.105.032375Pieterse, C. M. J., van Wees, S. C. M., van Pelt, J. A., Knoester, M., Laan, R., Gerrits, H., … van Loon, L. C. (1998). A Novel Signaling Pathway Controlling Induced Systemic Resistance in Arabidopsis. The Plant Cell, 10(9), 1571-1580. doi:10.1105/tpc.10.9.1571Berger, S., Bell, E., & Mullet, J. E. (1996). Two Methyl Jasmonate-Insensitive Mutants Show Altered Expression of AtVsp in Response to Methyl Jasmonate and Wounding. Plant Physiology, 111(2), 525-531. doi:10.1104/pp.111.2.525Attaran, E., Zeier, T. E., Griebel, T., & Zeier, J. (2009). Methyl Salicylate Production and Jasmonate Signaling Are Not Essential for Systemic Acquired Resistance in Arabidopsis. The Plant Cell, 21(3), 954-971. doi:10.1105/tpc.108.063164Yan, J., Zhang, C., Gu, M., Bai, Z., Zhang, W., Qi, T., … Xie, D. (2009). The Arabidopsis CORONATINE INSENSITIVE1 Protein Is a Jasmonate Receptor. The Plant Cell, 21(8), 2220-2236. doi:10.1105/tpc.109.065730Mittal, S. (1995). Role of the Phytotoxin Coronatine in the Infection ofAmbidopsis thalianabyPseudomonas syringaepv.tomato. Molecular Plant-Microbe Interactions, 8(1), 165. doi:10.1094/mpmi-8-0165Genoud, T., & Métraux, J.-P. (1999). Crosstalk in plant cell signaling: structure and function of the genetic network. Trends in Plant Science, 4(12), 503-507. doi:10.1016/s1360-1385(99)01498-3Lawton, K. A., Friedrich, L., Hunt, M., Weymann, K., Delaney, T., Kessmann, H., … Ryals, J. (1996). Benzothiadiazole induces disease resistance in Arabidopsis by activation of the systemic acquired resistance signal transduction pathway. The Plant Journal, 10(1), 71-82. doi:10.1046/j.1365-313x.1996.10010071.xFeys, B., Benedetti, C. E., Penfold, C. N., & Turner, J. G. (1994). Arabidopsis Mutants Selected for Resistance to the Phytotoxin Coronatine Are Male Sterile, Insensitive to Methyl Jasmonate, and Resistant to a Bacterial Pathogen. The Plant Cell, 751-759. doi:10.1105/tpc.6.5.751Sun, J., Xu, Y., Ye, S., Jiang, H., Chen, Q., Liu, F., … Li, C. (2009). Arabidopsis ASA1 Is Important for Jasmonate-Mediated Regulation of Auxin Biosynthesis and Transport during Lateral Root Formation. The Plant Cell, 21(5), 1495-1511. doi:10.1105/tpc.108.064303He, Y., Fukushige, H., Hildebrand, D. F., & Gan, S. (2002). Evidence Supporting a Role of Jasmonic Acid in Arabidopsis Leaf Senescence. Plant Physiology, 128(3), 876-884. doi:10.1104/pp.010843Shan, X., Zhang, Y., Peng, W., Wang, Z., & Xie, D. (2009). Molecular mechanism for jasmonate-induction of anthocyanin accumulation in Arabidopsis. Journal of Experimental Botany, 60(13), 3849-3860. doi:10.1093/jxb/erp223Yoshida, Y., Sano, R., Wada, T., Takabayashi, J., & Okada, K. (2009). Jasmonic acid control of GLABRA3 links inducible defense and trichome patterning in Arabidopsis. Development, 136(6), 1039-1048. doi:10.1242/dev.030585Borevitz, J. O., Xia, Y., Blount, J., Dixon, R. A., & Lamb, C. (2000). Activation Tagging Identifies a Conserved MYB Regulator of Phenylpropanoid Biosynthesis. The Plant Cell, 12(12), 2383-2393. doi:10.1105/tpc.12.12.2383Berger, S., Bell, E., Sadka, A., & Mullet, J. E. (1995). Arabidopsis thaliana Atvsp is homologous to soybean VspA and VspB, genes encoding vegetative storage protein acid phosphatases, and is regulated similarly by methyl jasmonate, wounding, sugars, light and phosphate. Plant Molecular Biology, 27(5), 933-942. doi:10.1007/bf00037021Feng, S., Ma, L., Wang, X., Xie, D., Dinesh-Kumar, S. P., Wei, N., & Deng, X. W. (2003). The COP9 Signalosome Interacts Physically with SCFCOI1 and Modulates Jasmonate Responses. The Plant Cell, 15(5), 1083-1094. doi:10.1105/tpc.010207Nawrath C, Métraux JP, Genoud T (2005) Chemical signals in plant resistance: salicylic acid. . In: Tuzun S, Bent E, editors. Multigenic and Induced Systemic Resistance in Plants. Dordrecht, Netherlands.: Springer US. pp. pp. 143–165.Kunkel, B. N., & Brooks, D. M. (2002). Cross talk between signaling pathways in pathogen defense. Current Opinion in Plant Biology, 5(4), 325-331. doi:10.1016/s1369-5266(02)00275-3Truman, W., Bennett, M. H., Kubigsteltig, I., Turnbull, C., & Grant, M. (2007). Arabidopsissystemic immunity uses conserved defense signaling pathways and is mediated by jasmonates. Proceedings of the National Academy of Sciences, 104(3), 1075-1080. doi:10.1073/pnas.0605423104Canet, J. V., Dobón, A., Ibáñez, F., Perales, L., & Tornero, P. (2010). Resistance and biomass in Arabidopsis: a new model for Salicylic Acid perception. Plant Biotechnology Journal, 8(2), 126-141. doi:10.1111/j.1467-7652.2009.00468.xCasimiro, I., Marchant, A., Bhalerao, R. P., Beeckman, T., Dhooge, S., Swarup, R., … Bennett, M. (2001). Auxin Transport Promotes Arabidopsis Lateral Root Initiation. The Plant Cell, 13(4), 843-852. doi:10.1105/tpc.13.4.843Celenza, J. L., Grisafi, P. L., & Fink, G. R. (1995). A pathway for lateral root formation in Arabidopsis thaliana. Genes & Development, 9(17), 2131-2142. doi:10.1101/gad.9.17.2131Traw, M. B., & Bergelson, J. (2003). Interactive Effects of Jasmonic Acid, Salicylic Acid, and Gibberellin on Induction of Trichomes in Arabidopsis. Plant Physiology, 133(3), 1367-1375. doi:10.1104/pp.103.027086Kloek, A. P., Verbsky, M. L., Sharma, S. B., Schoelz, J. E., Vogel, J., Klessig, D. F., & Kunkel, B. N. (2001). Resistance to Pseudomonas syringae conferred by an Arabidopsis thaliana coronatine-insensitive (coi1) mutation occurs through two distinct mechanisms. The Plant Journal, 26(5), 509-522. doi:10.1046/j.1365-313x.2001.01050.xXie, D. (1998). COI1: An Arabidopsis Gene Required for Jasmonate-Regulated Defense and Fertility. Science, 280(5366), 1091-1094. doi:10.1126/science.280.5366.1091Ellis, C., & Turner, J. (2002). A conditionally fertile coi1 allele indicates cross-talk between plant hormone signalling pathways in Arabidopsis thaliana seeds and young seedlings. Planta, 215(4), 549-556. doi:10.1007/s00425-002-0787-4Fernández-Arbaizar, A., Regalado, J. J., & Lorenzo, O. (2011). Isolation and Characterization of Novel Mutant Loci Suppressing the ABA Hypersensitivity of the Arabidopsis coronatine insensitive 1-16 (coi1-16) Mutant During Germination and Seedling Growth. Plant and Cell Physiology, 53(1), 53-63. doi:10.1093/pcp/pcr174He, Y., Chung, E.-H., Hubert, D. A., Tornero, P., & Dangl, J. L. (2012). Specific Missense Alleles of the Arabidopsis Jasmonic Acid Co-Receptor COI1 Regulate Innate Immune Receptor Accumulation and Function. PLoS Genetics, 8(10), e1003018. doi:10.1371/journal.pgen.1003018Xu, L., Liu, F., Lechner, E., Genschik, P., Crosby, W. L., Ma, H., … Xie, D. (2002). The SCFCOI1 Ubiquitin-Ligase Complexes Are Required for Jasmonate Response in Arabidopsis. The Plant Cell, 14(8), 1919-1935. doi:10.1105/tpc.003368Chini, A., Fonseca, S., Fernández, G., Adie, B., Chico, J. M., Lorenzo, O., … Solano, R. (2007). The JAZ family of repressors is the missing link in jasmonate signalling. Nature, 448(7154), 666-671. doi:10.1038/nature06006Grunewald, W., Vanholme, B., Pauwels, L., Plovie, E., Inzé, D., Gheysen, G., & Goossens, A. (2009). Expression of the Arabidopsis jasmonate signalling repressor JAZ1/TIFY10A is stimulated by auxin. EMBO reports, 10(8), 923-928. doi:10.1038/embor.2009.103Cao, H., Glazebrook, J., Clarke, J. D., Volko, S., & Dong, X. (1997). The Arabidopsis NPR1 Gene That Controls Systemic Acquired Resistance Encodes a Novel Protein Containing Ankyrin Repeats. Cell, 88(1), 57-63. doi:10.1016/s0092-8674(00)81858-9Century, K. S., Holub, E. B., & Staskawicz, B. J. (1995). NDR1, a locus of Arabidopsis thaliana that is required for disease resistance to both a bacterial and a fungal pathogen. Proceedings of the National Academy of Sciences, 92(14), 6597-6601. doi:10.1073/pnas.92.14.6597Wildermuth, M. C., Dewdney, J., Wu, G., & Ausubel, F. M. (2001). Isochorismate synthase is required to synthesize salicylic acid for plant defence. Nature, 414(6863), 562-565. doi:10.1038/35107108Lu, M., Tang, X., & Zhou, J.-M. (2001). Arabidopsis NHO1 Is Required for General Resistance against Pseudomonas Bacteria. The Plant Cell, 13(2), 437-447. doi:10.1105/tpc.13.2.437Ritter, C., & Dangl, J. L. (1996). Interference between Two Specific Pathogen Recognition Events Mediated by Distinct Plant Disease Resistance Genes. The Plant Cell, 251-257. doi:10.1105/tpc.8.2.251Tornero, P., & Dangl, J. L. (2002). A high-throughput method for quantifying growth of phytopathogenic bacteria in Arabidopsis thaliana. The Plant Journal, 28(4), 475-481. doi:10.1046/j.1365-313x.2001.01136.xMacho, A. P., Guevara, C. M., Tornero, P., Ruiz-Albert, J., & Beuzón, C. R. (2010). The Pseudomonas syringae effector protein HopZ1a suppresses effector-triggered immunity. New Phytologist, 187(4), 1018-1033. doi:10.1111/j.1469-8137.2010.03381.xTon, J., & Mauch-Mani, B. (2004). β-amino-butyric acid-induced resistance against necrotrophic pathogens is based on ABA-dependent priming for callose. The Plant Journal, 38(1), 119-130. doi:10.1111/j.1365-313x.2004.02028.xCANET, J. V., DOBÓN, A., ROIG, A., & TORNERO, P. (2010). Structure-function analysis of npr1 alleles in Arabidopsis reveals a role for its paralogs in the perception of salicylic acid. Plant, Cell & Environment, 33(11), 1911-1922. doi:10.1111/j.1365-3040.2010.02194.xJohnson, C. M., Stout, P. R., Broyer, T. C., & Carlton, A. B. (1957). Comparative chlorine requirements of different plant species. Plant and Soil, 8(4), 337-353. doi:10.1007/bf01666323Dobón, A., Canet, J. V., Perales, L., & Tornero, P. (2011). Quantitative genetic analysis of salicylic acid perception in Arabidopsis. Planta, 234(4), 671-684. doi:10.1007/s00425-011-1436-6Mehrtens, F., Kranz, H., Bednarek, P., & Weisshaar, B. (2005). The Arabidopsis Transcription Factor MYB12 Is a Flavonol-Specific Regulator of Phenylpropanoid Biosynthesis. Plant Physiology, 138(2), 1083-1096. doi:10.1104/pp.104.058032Konieczny, A., & Ausubel, F. M. (1993). A procedure for mapping Arabidopsis mutations using co-dominant ecotype-specific PCR-based markers. The Plant Journal, 4(2), 403-410. doi:10.1046/j.1365-313x.1993.04020403.xBell, C. J., & Ecker, J. R. (1994). Assignment of 30 Microsatellite Loci to the Linkage Map of Arabidopsis. Genomics, 19(1), 137-144. doi:10.1006/geno.1994.1023Swarbreck, D., Wilks, C., Lamesch, P., Berardini, T. Z., Garcia-Hernandez, M., Foerster, H., … Huala, E. (2007). The Arabidopsis Information Resource (TAIR): gene structure and function annotation. Nucleic Acids Research, 36(Database), D1009-D1014. doi:10.1093/nar/gkm965Jürgens G, Mayer U, Torres Ruiz RA, Berleth T, Mísera S (1991) Genetic analysis of pattern formation in the Arabidopsis embryo. Development (Supplement 1) : 27–38.Huang, W. E., Wang, H., Zheng, H., Huang, L., Singer, A. C., Thompson, I., & Whiteley, A. S. (2005). Chromosomally located gene fusions constructed in Acinetobacter sp. ADP1 for the detection of salicylate. Environmental Microbiology, 7(9), 1339-1348. doi:10.1111/j.1462-5822.2005.00821.xDeFraia, C. T., Schmelz, E. A., & Mou, Z. (2008). A rapid biosensor-based method for quantification of free and glucose-conjugated salicylic acid. Plant Methods, 4(1), 28. doi:10.1186/1746-4811-4-28Chenna, R. (2003). Multiple sequence alignment with the Clustal series of programs. Nucleic Acids Research, 31(13), 3497-3500. doi:10.1093/nar/gkg50

Meeting Disciplinary Literacy Demands in Content Learning: The Singapore Perspective

This chapter examines how systemic language and literacy support for content-area teachers to enhance their students’ learning is realised in Singapore with a focus on science at the secondary level. It highlights theoretical underpinnings that inform the perspective of disciplinary literacy guiding this work and describes how disciplinary literacy is contextualised in Singapore against what is broadly understood as effective communication. It unpacks the nature and extent of systemic support for developing literacy in science with specific reference to the professional learning courses and school-based collaborative research. The chapter addresses the challenges encountered and discusses the implications which impact curriculum and pedagogy in the integration of disciplinary literacy practices to meet students’ needs in the learning of science