Project description:Disease outbreaks due to the consumption of legume seedlings contaminated with human enteric bacterial pathogens like Escherichia coli O157:H7 and Salmonella enterica are reported every year. We found surface and internal colonization of Medicago truncatula by Salmonella enterica and Escherichia coli O157:H7 even with inoculum levels as low as two bacteria per plant. Expression analyses using microarray revealed that some Medicago truncatula genes were regulated in a similar manner in response to both of these enteric pathogens. Medicago truncatula roots were inoculated with low inoculum levels of two enteric bacteria per plant (E. coli O157:H7 and Salmonella). 10 days post inoculated plants were used for RNA extraction and hybridization on Affymetrix microarrays.
Project description:Disease outbreaks due to the consumption of legume seedlings contaminated with human enteric bacterial pathogens like Escherichia coli O157:H7 and Salmonella enterica are reported every year. We found surface and internal colonization of Medicago truncatula by Salmonella enterica and Escherichia coli O157:H7 even with inoculum levels as low as two bacteria per plant. Expression analyses using microarray revealed that some Medicago truncatula genes were regulated in a similar manner in response to both of these enteric pathogens.
Project description:The enteric nervous system (ENS) controls several intestinal functions including motility and nutrient handling, which can be disrupted by infection-induced neuropathies or neuronal cell death. We investigated possible tolerance mechanisms preventing neuronal loss and disruption in gut motility after pathogen exposure. We found that following enteric infections, muscularis macrophages (MMs) acquire a tissue-protective phenotype that prevents neuronal loss and dysmotility during subsequent challenge with unrelated pathogens. Bacteria-induced neuroprotection relied on activation of gut-projecting sympathetic neurons and signaling via b2-adrenergic receptors (b2AR) on MMs. In contrast, helminth-mediated neuroprotection was dependent on T cells and systemic production of interleukin (IL)-4 and -13 by eosinophils, which induced arginase-expressing MMs that prevented neuronal loss from an unrelated infection located in a different intestinal region. Collectively, these data suggest that distinct enteric pathogens trigger a state of disease- or tissue tolerance that preserves ENS number and functionality.
Project description:Lettuce is one of most consumed vegetables globally. This crop is susceptible to abiotic stresses. To understand the molecular mechanisms of stress response in lettuce, global transcriptome analysis was conducted. This analysis revealed distinctive temporal expression patterns among the stress-regulated genes in lettuce plants exposed to abiotic stresses
Project description:The draft genome of L. sativa (lettuce) cv. Tizian was sequenced in two Illumina sequencing runs, mate pair and shotgun. This entry contains the RAW sequencing data.
Project description:The cell wall is among the first plant structures encountered by necrotrophic fungal pathogens, such as Botrytis cinerea. The composition of plant cell walls varies depending on the species, type of cell or tissue, and stage of development. Cell walls are important reservoirs of energy-rich sugars for pathogens, but also are barriers that impair colonization of host tissues. Growing fungal hyphae secrete enzymes that hydrolyze cell wall polysaccharides. Degradation of wall polysaccharides provides nutrients for the pathogen and improves the access of secreted Botrytis enzymes to all host cell wall targets and cytoplasmic constituents. Destruction of host cell walls results in tissue maceration, a hallmark of diseases caused by Botrytis. The Botrytis genome encodes 1,155 predicted carbohydrate-active enzyme (CAZy) genes; products of 275 are potentially secreted. Transcriptome sequencing identified Botrytis CAZy genes expressed during infections of lettuce leaves, ripe tomato fruit and grape berries. On all three hosts, Botrytis expresses a common group of 229 predicted CAZy genes including 28 pectin-modifying enzymes, 21 hemicellulose-modifying proteins, 18 enzymes targeting pectin and hemicellulose side-branches, and 16 enzymes that may degrade cellulose. Pectin polysaccharides are abundant in grape and tomato cell walls, but lettuce leaf walls are predominantly hemicelluloses and cellulose. These results suggest that Botrytis targets similar wall polysaccharide networks; e.g., pectins, on leaves and fruit, but also attacks unique host wall polysaccharide substrates The diversity of the Botrytis CAZy proteins may be partly responsible for its wide host range. 3 biological replicates consisting of groups of infected tomato fruits from different plants
Project description:The cell wall is among the first plant structures encountered by necrotrophic fungal pathogens, such as Botrytis cinerea. The composition of plant cell walls varies depending on the species, type of cell or tissue, and stage of development. Cell walls are important reservoirs of energy-rich sugars for pathogens, but also are barriers that impair colonization of host tissues. Growing fungal hyphae secrete enzymes that hydrolyze cell wall polysaccharides. Degradation of wall polysaccharides provides nutrients for the pathogen and improves the access of secreted Botrytis enzymes to all host cell wall targets and cytoplasmic constituents. Destruction of host cell walls results in tissue maceration, a hallmark of diseases caused by Botrytis. The Botrytis genome encodes 1,155 predicted carbohydrate-active enzyme (CAZy) genes; products of 275 are potentially secreted. Transcriptome sequencing identified Botrytis CAZy genes expressed during infections of lettuce leaves, ripe tomato fruit and grape berries. On all three hosts, Botrytis expresses a common group of 229 predicted CAZy genes including 28 pectin-modifying enzymes, 21 hemicellulose-modifying proteins, 18 enzymes targeting pectin and hemicellulose side-branches, and 16 enzymes that may degrade cellulose. Pectin polysaccharides are abundant in grape and tomato cell walls, but lettuce leaf walls are predominantly hemicelluloses and cellulose. These results suggest that Botrytis targets similar wall polysaccharide networks; e.g., pectins, on leaves and fruit, but also attacks unique host wall polysaccharide substrates The diversity of the Botrytis CAZy proteins may be partly responsible for its wide host range. 4 biological replicates consisting of groups of infected berries from different plants