Project description:Comparison of the binding of GOLDEN2-LIKE (GLK) transcription factors in tomato, tobacco, Arabidopsis, maize and rice, show that genome cis-variation caused wide-spread TF binding divergence, and most of the TF binding sites are genetically redundant.
Project description:To investigate and compare the influence of root exudates of tomato and maize on Pseudomonas donghuensis P482, we have grown the strain up to a stationary phase in M9 0.4% glucose medium supplemented with maize exudates (Maize), tomato exudates (Tomato) or without supplementation (Control). We then performed differential gene expression analysis, identifying changes in transcriptome profiles between each treatment (Tomato, Maize) and the Control as reference conditions, and between the two treatments.
Project description:To test the hypothesis that gene expression by the fungal partner in this beneficial interaction is modulated by the plant host, Trichoderma virens was co-cultured with maize or tomato in a hydroponic system allowing interaction with the roots. The transcriptomes for T. virens alone were compared with fungus-inoculated tomato or maize roots by hybridization on oligonucleotide microarrays Based on the relevant role of Trichoderma virens as a biological control agent this study provides a better knowledge of its crosstalk with plants in a host-specific manner.
Project description:To test the hypothesis that gene expression by the fungal partner in this beneficial interaction is modulated by the plant host, Trichoderma virens was co-cultured with maize or tomato in a hydroponic system allowing interaction with the roots. The transcriptomes for T. virens alone were compared with fungus-inoculated tomato or maize roots by hybridization on oligonucleotide microarrays Based on the relevant role of Trichoderma virens as a biological control agent this study provides a better knowledge of its crosstalk with plants in a host-specific manner. Trichoderma virens was co-cultured for three days with maize or tomato in a hydroponic system allowing interaction with the roots. 3 experiments were performed for each treatment, and compared to 5 experiments with T. virens grown under the same conditions without plants.
Project description:An intriguing new paradigm in plant biology is that systemically-mobile mRNAs play a role in coordinating development. In this process, specific mRNAs are loaded into the phloem transport stream for translocation to distant tissues, where they may impact developmental processes. However, despite its potential significance for plant growth regulation, mRNA trafficking remains poorly understood and challenging to study. Here we show that phloem-mobile mRNAs can also traffic between widely divergent species from a host to the plant parasite, lespedeza dodder (Cuscuta pentagona Engelm.). Reverse transcriptase PCR (RT-PCR) and microarray analysis were used to detect specific tomato transcripts in dodder grown on tomato (Lycopersicon esculentum Mill.) that were not present in control dodder grown on other host species. The foreign transcripts included LeGAI, which has been previously shown to be translocated in the phloem, as well as nine other transcripts not reported to be mobile. Dodders are parasitic plants that obtain resources by drawing from the phloem of a host plant, and have joint plasmodesmata with host cortical cells. Although viruses are known to move between dodder and its hosts, translocation of endogenous plant mRNA has not been reported. These results point to a potentially new level of interspecies communication, and raise questions about the ability of parasites to recognize, use, and respond to transcripts acquired from their hosts. Experiment Overall Design: In order to identify potential tomato transcripts in dodder, microarray analysis was performed on RNA from dodder and hosts. Total RNA was extracted from the tomato host and from dodder grown on tomato, Arabidopsis, tobacco, or pumpkin. The host tomato RNA was included to verify that any transcripts detected in the parasite were in fact expressed in the host. The dodder samples grown on tobacco, Arabidopsis, and pumpkin served as controls for dodder genes that may cross-hybridize with tomato array probes, with three different host species used to minimize any host-specific effects on dodder gene expression. Samples were analyzed using the Affymetrix GeneChip Tomato Array and transcripts scored for presence or absence in each sample. Considering that host transcripts present in dodder would be at low levels and diluted with dodder transcripts, a P-value of 0.06 in at least two of three biological replicates was used as the threshold for scoring a transcript as being present.
Project description:The depiction of maize chromatin architecture using Assay for Transposase Accessible Chromatin with high-throughput sequencing (ATAC-seq) provides great opportunities to investigate cis-regulatory elements, which is crucial for crop improvement. We demonstrate a streamlined ATAC-seq protocol for maize in which nuclei purification can be achieved without cell sorting, and using only a standard bench-top centrifuge. Our protocol, coupled with the bioinformatic analysis, provides a precise and efficient assessment of the maize chromatin landscape.
Project description:Transcriptome analysis in tobacco mutant plants using tomato Genechip Genome array Tobacco (Nicotiana tabacum cv. Petit Havanna) psaA and psbA deletion mutants were constructed through a targeted deletion of 767 and 1152 nucleotides of coding regions, respectively with two gene cassettes: psbAproR:uidA:psbterR and rrnR:aadA:rbcLterR coding for GUS reporter and spectinomycin selectable marker genes, respectively. Standard established procedures were followed for chloroplast transformation to generate the psaA and psbA deletion mutants based on the homologous recombination. Gene expression profiles in psaA and psbA tobacco mutant plants were analyzed using tomato Genechip Genome array to study the global changes in the expression of genome.
Project description:The soil-borne bacterial pathogen Ralstonia solanacearum invades a broad range of plants through roots, resulting in wilting of the plant, but no effective protection against this disease has been developed. Two R. solanacearum resistance-inducing compounds were biochemically isolated from tobacco and identified as sclareol and cis-abienol, diterpenes. When exogenously applied to their roots, these diterpenes induced resistance to R. solanacearum in tobacco, tomato, and Arabidopsis plants without exhibiting any antimicrobial activity. Structure-activity correlation analysis of sclareol-related compounds revealed that the hydroxyl group at the eighth carbon position is responsible for the activity for inducing resistance. Microarray analysis identified many sclareol-responsive Arabidopsis genes, such as those encoding or with role in ABC transporters, biosynthesis and signaling of defense-related signal molecules, and mitogen-activated protein kinase (MAPK) cascades. Sclareol-induced R. solanacearum resistance was partially compromised in Arabidopsis mutants defective in the ABC transporter AtPDR12, the MAPK MPK3, and ethylene and abscisic acid signaling pathways. Transgenic tobacco plants in which NtPDR1, a tobacco homolog of AtPDR12, was silenced exhibited also reduced resistance. These results suggest that multiple host factors are involved in resistance to R. solanacearum induced by sclareol and its related compounds and that these compounds can be used to protect crops from bacterial wilt disease.
Project description:Maize (Zea mays) is one of the most important crop in the world. Better understanding the maize chromatin architecture points to novel approaches to improve crop yield. Here, we describe the first ATAC-seq protocol to assess the maize genome. Fresh leaf tissue was gently chopped by a blade to release intact nuclei which later were fractionated using Percoll-sucrose gradient. The isolated nuclei were treated with a transposase that fragments and tags the genome; these fragments were subjected to two rounds of PCR to generate the ATAC-seq library. In the first round of PCR, these fragments were amplified with 5 cycles and sequencing barcodes were added. A fraction of the first PCR product was subjected to qPCR to determine the optimal amplification cycle number in the second round of PCR. The library quality can be assessed by a Bioanalyzer prior to sequencing. The distinct bands indicated good quality. After sequencing, the computational analysis of fragment size distribution may show patterns of periodicity that is a characteristic to ATAC-seq libraries. In our preliminary analysis, we found that 85% percent of the identified regions deviate from closed regions previously identified by MNase-seq, suggesting that the ATAC-seq library preparation procedure described here is effective in identifying open chromatin regions of the maize genome.