Project description:We used RNAseq to quantify trascript expression from three populations of Conyza sumatrensis before and 5 hours after treatment with 2,4-D. This study investigates different responses between a 2,4-D resistant biotype compared to a 2,4-D sensitive biotype.
Project description:Nontarget-site resistance due to rapid physiological response in 2,4-D resistant Conyza sumatrensis: Reduced 2,4-D translocation and auxin-induced gene expression
Project description:Resistance to the phenoxy synthetic auxin herbicide 2,4-D is conferred by a deletion mutation in the degron tail of IAA2. An RNA-Seq experiment was used to assemble a reference transcriptome for the weed species Sisymbrium orientale, to quantify gene expression, and to identify sequence variants in the alignments. A 27 bp deletion was identified in the IAA2 gene. Forward genetics supported the role of this deletion mutation in resistance. The IAA2 deletion allele was transformed into Arabidopsis thaliana to confirm that it conferred 2,4-D resistance.
Project description:Giant ragweed (Ambrosia trifida) is an economically disruptive weed in US corn and soybean production. Populations of this species have evolved a unique glyphosate resistance mechanism involving rapid cell death in mature leaves, also known as rapid necrosis. This abiotic stress resistance mechanism may be due to utilization of stress response pathways typically associated with biotic stresses such as pathogens. To study the genetic basis of this rapid response, an RNA-Seq time course study was conducted on young and mature leaves of glyphosate-resistant and -susceptible individuals, before and after glyphosate treatment. A major difference in gene regulation following glyphosate application was observed between young and mature leaves in the glyphosate-resistant individuals. Many differentially expressed genes were related to broad plant pathways with cross-functionality including plant stress and cell death pathways, phytohormone synthesis, response to oxidative stress, cellular metabolism, and pathogen defense pathways. Metabolic network analysis revealed that most of the genes involved in jasmonate biosynthesis were up regulated in response to glyphosate treatment in resistant mature leaves whereas this pathway was not induced in susceptible plants. The glyphosate-resistant plants appear to perceive glyphosate differently than susceptible plants, pointing to the potential role of a yet to be characterized receptor that senses glyphosate or its action and triggers the rapid necrosis response in mature leaves. Additional steps are needed for functional validation to test the hypothesis of causal relationship between function of these candidate genes of interest and the glyphosate resistance rapid response phenotype.
Project description:To identify intrinsic mechanismis that mediating Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) resistance , gene expression analysis was performed on MDA-MB-231 cell lines exposed to TRAIL, in parental (Sensitive) or treat to resistance (TTR) conditions.
