Sweet orange genes regulated by Xanthomonas citri (Xc) in the presence or absence of cycloheximide (Ch), or Ch alone
ABSTRACT: Microarray analyses of sweet orange leaves infiltrated with Xc in the presence or absence of Ch, or Ch alone This experiment was used to identify genes up-regulated by Xc independently of protein synthesis Citrus leaves were infiltrated with a suspension of Xc with or without Ch, and mRNA was extrated and processed 8h post inoculation (8hpi)
Project description:We have used the citrus GeneChip array (GPL5731) to survey the transcription profiles of sweet orange in response to the bacterial pathogens Xanthomonas axonopodis pv. citri (Xac) and Xanthomonas axonopodis pv. aurantifolii (Xaa). Xac is the causal agent of the citrus canker disease on a wide range of citrus species, including sweet oranges (Citrus sinensis). On the other hand, Xaa is pathogenic to Mexican lime (Citrus aurantifolia) only, and in sweet orange it triggers a defense response. In order to identify the genes induced during the defense response (Xaa-responsive genes) or citrus canker development (Xac-responsive genes), we conducted microarrays hybridization experiments at 6 and 48 hours after bacterial infiltration (habi). The analysis revealed that genes commonly modulated by Xac and Xaa are associated with basal defenses normally triggered by pathogen-associated molecular patterns, including those involved in reactive oxygen species production and lignification. Significantly, Xac-infected leaves showed considerable changes in the transcriptional profiles of defense-, cell wall-, vesicle trafficking- and cell growth-related genes between 6 and 48 habi. This is consistent with the notion that Xac suppresses host defenses near the beginning of the infection and simultaneously changes the physiological status of the host to promote cell enlargement and division. Finally, Xaa triggered a MAP kinase signaling pathway involving WRKY and ethylene-responsive transcriptional factors known to activate downstream defense genes. Keywords: Comprehensive transcriptional analysis of the Citrus-Xanthomonas interaction Adult leaves of sweet orange were infiltrated with the bacterial suspensions or water (mock control). Two stages were selected after bacterial infiltration for RNA extraction and hybridization on Affymetrix microarrays. In total, these experiments consist of two biological replicates of six samples: water-infiltrated leaves, Xaa-infiltrated leaves and Xac-infiltrated leaves, at both 6 and 48 (habi).
Project description:Identification of AvrRpt2-mediated differential gene expression in Arabidopsis Four-week-old leaves of Arabidopsis Col-0 plant were infiltrated with Pseudomonas syringae pv. Maculicola carring effector AvrRpt2 at OD0.01. Samples were collected at 0 or 6 hours after infiltration. Each time point contains three biological replicates.
Project description:Comparative transcriptome analysis was performed to study differentially expressed genes (DEGs) between CK and Cocytodes caerulea Guenée challenged (CH) leaves of ramie.We obtained 40.2 and 62.8 million reads for CH and CK libraries respectively.De novo assembling of these reads generated 26,759 and 29,988 unigenes respectively. After a integrate assembly for all data of these two libraries, a total of 46,533 unigenes with an average length of 845 bp were obtained.A total of 1179 genes were identified as DEGs, 657 and 1230 of them were up- and down- regulated respectively, in response to C.caerulea infestation. Leaf samples of Cocytodes caerulea infested (T2) and un-infested (T1) ramie were RNA-Seq sequenced to compare differented expressed genes.
Project description:Identification of differential gene expression during RPS2-mediated effector-triggered immunity in Arabidopsis Four-week-old leaves of Arabidopsis Col-0 wild type and rps2 mutant plant were infiltrated with Pseudomonas syringae pv. Maculicola carring effector AvrRpt2 at OD 0.01. Samples were collected at 0, 6 and 10 hours after infiltration for WT plants and at 0 and 10 hours after infiltration for rps2 plants. Three biological replicates were performed per genotype per time point.
Project description:Microbe associated molecular pattern (MAMP)-responsive genes were identified in leaves of four different genotypes. The genotypes used in this study were: LD0-2817P; LDX01-1-65; Ripley and EF59. Leaves from three-weeks old plants were used in this study We used microarray to identified the MAMP-responsive genes in leaves of four soybean genotypes trated with 1 uM flg22 and 50 ug/ml chitin for 30 minutes Trifoliolate leaves from three-week-old plants were detached and then vacuumed infiltrated with ddiH2O for 2 min. Water-infiltrated trifoliolate leaves from five different plants of each genotype were pooled and cut into approximately 1 cm2 slices. Equal amount of leaf slices (~30 slices) were transferred into two different Petri dishes and then floated overnight on autoclaved ddiH2O. Water was removed from both Petri dishes and was replaced with 5 ml of MAMP solution [1 mM flagellin 22 (flg22) and 50 mg of crab shell chitin (called in this study as chitin)], or 5 ml of mock solution [autoclaved ddiH2O plus equivalent amount of dimethyl sulfoxide (DMSO). DMSO was included since it was contained in the solution used to dissolve the flg22 peptide]. After a 30 min treatment, mock- and MAMP-treated leaf slices were harvested into different tubes and immediately frozen in liquid nitrogen. Samples were stored at -80 until use. All procedures described above were performed under dark conditions.
Project description:This study aimed at decrypting the transcriptomic response of 2 months-old grown tender wheat (cv Chinese Spring) to a the Xanthomonas translucens pathogen infection by infiltration. The response was monitored by RNAseq 24h post leaf clipping. Triticum aestivum cv. Chinese Spring plants were maintained in a growth chamber with cycles of 12 h of light at 21C and 50% relative humidity (RH) and 12 h of dark at 21C and 50% RH. Leaves of 49 days-old plants were infiltrated with a bacterial suspension in water with an optical density at 600 nm (OD600) of 0.5 using a needleless syringe. Plants inoculated with water were used as controls. For transcriptomic and proteomic analyses, leaves and root tissues were harvested 1 day post-inoculation (dpi), when symptoms were not visible yet. Three biological replicates per treatment were performed, and each with pooled leaves from two independent plants per replicate. The files per conditions and replicates are:Sample 1 Root tissue with 3 replicates: CONTROL * control condition for roots (wheat without pathogen infection): 3 replicates: 1.1R,1.2R, 1.3R * control condition for leaves (wheat without pathogen infection): 3 replicates1.1L,1.2L, 1.3L * Wheat Roots infected by Xanthomonas translucens: 3 replicates: 5.1R, 5.2R, 5.3R * Wheat Leaves infected by Xanthomonas translucens: 3 replicates: 5.1L, 5.2L, 5.3L
Project description:Citrus Huanglongbing (HLB, or greening) is one of the most severe diseases of citrus. Plant disease symptom development is considered to be the consequence of a number of molecular, cellular and physiological changes, and may also be associated with host defense responses. Understanding citrus host response to HLB may contribute to the development of new strategies to control this destructive disease. We performed microarray analysis to identify the differentially expressed genes in sweet orange in response to HLB infection using the Affymetrix GeneChip® citrus genome array. Two-year-old seedlings of ‘Madam Vinous’ sweet orange (Citrus sinensis L. Osbeck) were inoculated by grafting with bud sticks from HLB-diseased, PCR positive sweet orange plants. For mock-inoculated controls, the same types of plants were grafted with bud sticks from HLB-free, PCR negative sweet orange. At 7 months after inoculation, mature leaves were sampled from 3 individual HLB-diseased plants, and healthy leaves from 3 mock-inoculated plants as control. Total RNA was extracted from leaf samples and hybridized on Affymetrix microarrays.
Project description:Treatment of rice tissues with purified preparations of a Xanthomonas oryzae pv. oryzae (Xoo) secreted plant cell wall degrading enzyme, Lipase/Esterase (LipA), elicits cell wall damage induced innate immune responses. LipA activity is required for induction of defense responses. In order to characterize the early events during elaboration of cell wall degrading enzyme, Lipase/Esterase (LipA) induced innate immune response in rice, we have performed global gene expression profiling of rice leaves treated with purified LipA at early time points, 30 minutes and 120min, after treatment. Whole genome transcriptional profiling was performed using Affymetrix Rice GeneChips Leaves of two weeks old green house grown susceptible rice cultivar (Taichung Native-1; TN-1) were infiltrated with either 30-40μl of purified Xoo Lipase/Esterase (LipA)(500μg/ml) or with buffer (10mM potassium phosphate buffer pH 6.0) alone (as described in Jha et al. 2007; MPMI vol 20, pp 31-40). The plants were shifted to a growth chamber (28oC; 80% relative humidity; 12/12h light/dark cycle) 48 hours before the treatment. 20-30 leaf pieces covering the infiltrated zone from each of the treatments were harvested 30 min. and 120 min. after infiltration. Total RNA isolated from the pooled samples was subjected for expression analysis using Affymetrix GeneChip System. The experiment was repeated with three different biological replicates using RNA isolated from three batches of rice leaves treated with the freshly purified Xoo Lipase/Esterase (LipA)and the buffer Gene Expression profiling of rice leaves undergoing an innate immune respone induced by LipA (Lipase/Esterase A) enzyme
Project description:• A comparison of the transcriptomes of russeted vs. waxy apple exocarps previously highlighted a tight relationship between a gene encoding a MYB-type transcription factor, MdMYB93, and some key suberin biosynthetic genes. The present work assesses the role of this transcription factor in the suberization process. • A phylogenetic analysis of MdMYB93 and Arabidopsis thaliana MYBs was performed and the function of MdMYB93 was further investigated using Agrobacterium-mediated transient overexpression in Nicotiana benthamiana leaves. An RNA-Seq analysis was performed to highlight the MdMYB93-regulated genes. UPLC-TripleTOF and GC-MS were used to investigate alterations in phenylpropanoid, soluble free lipid, and lipid polyester contents. • A massive accumulation of suberin and its biosynthetic precursors in MdMYB93 agro-infiltrated leaves was accompanied by a remobilization of phenylpropanoids and an increased amount of lignin precursors. Gene expression profiling displayed a concomitant alteration of lipid and phenylpropanoid metabolism, cell wall development, and extracellular transport, with a large number of induced transcripts predicted to be involved in suberin deposition. • The present work supports a major role of MdMYB93 in the regulation of suberin deposition in russeted apple skins, from the synthesis of monomeric precursors, their transport, polymerization, and final deposition as suberin in primary cell wall. In order to draw a consistent picture of a gene expression profile of the MYB93 induced was performed comparing of 4 biological replicates of Nicotiana benthamiana leaves infiltrated with Pearleygate103 35S::MdMYB93 and 4 biological replicates of control plants infiltrated with P19 only.