Project description:Transcriptome profiling of three developmental stages of immature male gametophyte intobacco (Nicotiana tabacum) Total RNA isolated from tobacco microspores and early and late bicellular pollen was hybridised on Agilent Tobacco Gene Expression Microarray 4x44K in two biological replicates per sample
Project description:Gene expression was measured in different tissues throughout the lifecycle of the Nicotiana tabacum plant to generate the Tobacco Expression Atlas (TobEA).
Project description:A study was carried out to compare gene expression levels between technical replicate samples in order to test the reproducibility of a custom Affymetrix microarray for Tobacco (Nicotiana tabacum).
Project description:Pollen development is one of the most heat-sensitive developmental stages in a wide range of crops. Our longer-term goal is to understand the mechanism how starch metabolism in maturing pollen grains of the Solanaceae family contributes to maintaining higher pollen quality under heat-stress conditions. The specific aim of the suggested proposal is to characterize N. sylvestris WT and mutant (starch-deficient) transcriptomes during microgametogenesis under ambient and heat-stress conditions. Expression profiles of maturing microspores derived from flower buds at developmental stage of 4 to 2 days before flower opening will be obtained. Pollen was derived from WT and mutant plants exposed to either ambient or heat-stress conditions (exposing the plants to 45oC for 2.5 hours). Keywords: Loop design
Project description:The number of known proteins associated with plant lipid droplets (LDs) is small compared to other organelles. Many questions of LD biosynthesis and degradation remain open, also due to lack of candidate LD proteins whose characterization could help to elucidate their function in those processes. We performed a proteomic screen on LDs isolated from Nicotiana tabacum pollen tubes. Proteins that were highly enriched in the LD fraction compared to the total or cytosolic fraction where verified for LD localization via transient expression in tobacco pollen tubes. We also compared the isoforms of typical LD proteins found in the pollen tubes on a qualitative level to the isoforms found in tobacco seeds.
Project description:Although Pseudomonas aeruginosa is an opportunistic pathogen that does not often naturally infect alternate hosts such as plants, the plant-P. aeruginosa model has become a widely recognized system for identifying new virulence determinants and studying pathogenesis of this organism. Here we examine how both host factors and P. aeruginosa PAO1 gene expression are affected in planta after infiltration into incompatible and compatible cultivars of tobacco (Nicotiana tabacum L.) Nicotiana tabacum has a resistance gene (N) against tobacco mosaic virus; and although resistance to PAO1 infection correlated to the presence of a dominant N-gene, our data suggests that it is not a factor in resistance against Pseudomonas. We did observe that the resistant tobacco cultivar had higher basal levels of salicylic acid, and a stronger salicylic acid response upon infiltration of PAO1. Salicylic acid acts as a signal to activate defense responses in plants, limiting the spread of the pathogen and preventng access to nutrients. It has also been shown to have direct virulence modulating effects on P. aeruginosa. We also examined host effects on the pathogen by analyzing global gene expression profiles of bacteria removed from the intracellular fluid of the two plant hosts. We discovered that the availability of micronutrients, particularly sulfate and Pi, are important factors in in planta pathogenesis, and that the amounts of these nutrients made available to the bacteria may in turn have an effect on virulence gene expression. Indeed, there are several reports suggesting that P. aeruginosa virulence is influenced in mammalian hosts by the availability of iron and by levels of O2. Experiment Overall Design: Pseudomonas aeruginosa cells were removed from leaf tissue 24 hours post-infiltration and RNA was directly extracted from these cells. Comparisons are between cells removed from a susceptible cultivar of Nicotiana tabacum (cv. Samsun) and a resistant cultivar (cv. Xanthi). Three biological replicates per cultivar were analyzed.
Project description:Fatty acid-amino acid conjugates (FACs) in the oral secretion (OS) of the Manduca sexta larvae are necessary and sufficient to elicit the herbivory-specific responses in Nicotiana attenuata, an annual wild tobacco species. We used SuperSAGE combined with 454 sequencing to quantify the early transcriptional changes elicited by the FAC N-linolenoyl-glutamic acid (18:3-Glu) in N. attenuata. The second fully expanded leaf of rosette stage plants were wounded by rolling a fabric pattern wheel three times on each side of the midvein and the wounds were immediately supplied with either 20 uL of 0.02% (v/v) Tween-20/water (solvent control) or 10 uL of synthetic N-linolenoyl-glutamic acid (18:3-Glu; 0.03 nmol/µL in 0.02% (v/v) Tween-20/water). Tissue was collected after 30 min of the treatments and frozen in liquid nitrogen. Total RNA was extracted by the phenol/chloroform-LiCl method and poly(A)+-RNA was purified from total RNA. Subsequent steps for the construction of the SuperSAGE libraries and 454 sequencing were performed as previously described using double NlaIII digestions (Molina et al., 2008, BMC Genomics, 9:553). Two SuperSAGE libraries were generated after wounding and FAC elicitation of Nicotiana attenuata leaves. Leaves were harvested after 30 min of the treatments, total RNA extracted, polyA+ mRNA isolated and used for cDNA synthesis and SuperSAGE analysis as described my Matsumura et al (2003).