Huanglongbing (HLB) (=citrus greening) is a destructive disease of citrus which is caused by a fastidious, phloem-inhabiting bacterium of the genus Candidatus Liberibacter. Large-scale analysis of gene expression changes in Valencia orange leaves were studied during the course of 19 weeks after inoculation with Ca. L. asiaticus using the Affymetrix GeneChip citrus genome array to provide new insights into the molecular basis of citrus response to this pathogen. Of the more than 33,000 probe sets on the microarray 21,067 were expressed in the leaves, of which 279 and 515 were differentially expressed (FDR 0.05) five to nine and 13-17 weeks after inoculation, respectively. Results from semi-quantitative RT-PCR analysis performed on 14 selected genes were highly correlated with those observed with the microarray. Gene expression changes involved a variety of different processes including cell defense, transport, cellular organization, photosynthesis, and carbohydrate metabolism. Notable was the pathogen-induced accumulation of transcripts for a phloem-specific lectin PP2-like protein. Transcriptional changes and their relation to disease symptom development are discussed. This is the first study of transcriptional profiling in citrus in response to liberibacter infection using microarray technology.
No associated publication
Specimen part
View SamplesUnderstanding the mechanism of low temperature (LT) adaptation is crucial to the development of cold-tolerant crops. To identify the genes involved in the development of LT tolerance in the crown of hexaploid wheat we examined the global changes in genes expression during cold-treatment using the Affymetrix Wheat Genome Chip.
Genome-wide gene expression analysis supports a developmental model of low temperature tolerance gene regulation in wheat (Triticum aestivum L.).
No sample metadata fields
View SamplesOzone pollution decreases plant growth and yield worldwide. Some of the effects are genetically-mediated and are reported to involve G-protein signaling pathways. Effects of ozone on gene expression were examined in wild-type and G-protein null mutants to determine affected genes and to determine differential responses that may help define affected pathways.
Minimal influence of G-protein null mutations on ozone-induced changes in gene expression, foliar injury, gas exchange and peroxidase activity in Arabidopsis thaliana L.
Treatment, Time
View SamplesMicroarray expression profiling was used to identify genes expressed in developing soybean (Glycine max) seeds that are controlled by the circadian clock. Plants with developing seeds were entrained to 12hour light: 12 hour dark cycles and sampled in constant light conditions.
No associated publication
Specimen part, Time
View SamplesThe embryo to neonate transition is a critical period of development that has significant impact on broiler production. During this time important genetic programs governing metabolism and growth are established. The goal of this work was to study the effects of early post-hatch (PH) development and time of initiation of feeding on activation of the genetic programs regulating tissue growth and metabolism in liver, brain, duodenum and breast muscle in broiler chickens.
No associated publication
Sex, Age, Specimen part
View SamplesWe were interested in investigating the transcriptome responses to exogenous applications of brassinosteroid hormone when Arabidopsis seedlings are pre-stressed with a reactive oxygen species, hydrogen peroxide. We were interested in seeing which subsets of BR-responsive gene transcripts were most affected and how BR-responsive gene transcripts responded to increasing concentrations of hydrogen peroxide both as a whole and individually.
No associated publication
Specimen part
View SamplesBackground:
Natural variants of AtHKT1 enhance Na+ accumulation in two wild populations of Arabidopsis.
Specimen part
View SamplesMicroarray expression profiling was used to identify genes expressed misexpressed in wild-type Arabidopsis seedlings treated with 5-aza-2 deoxyctidine (5AC) or trichostatin A (TSA), and in decrease in dna methylation1 (ddm1) mutant seedlings.
Changes in global gene expression in response to chemical and genetic perturbation of chromatin structure.
Specimen part
View SamplesABSTRACT: Background: Though central to our understanding of how roots perform their vital function of scavenging water and solutes from the soil, no direct genetic evidence currently exists to support the foundational model that suberin acts to form a chemical barrier limiting the extracellular, or apoplastic, transport of water and solutes in plant roots.
Root suberin forms an extracellular barrier that affects water relations and mineral nutrition in Arabidopsis.
Specimen part
View SamplesWe performed a genome-wide transcriptional analysis in the mammary gland in a mouse model of E. coli mastitis using high-density mouse oligonucleotide microarrays.
No associated publication
No sample metadata fields
View Samples