Transcription profiling of maize to identify gene expression changes after chilling for 28 hours (acclimation phase)
Ontology highlight
ABSTRACT: The aim of this study was to identify alarm (fast) and acclimation phase (delayed) changes in the gene expression pattern in leaves of maize (CM 109 genotype) subjected to moderate chilling for 28 hours.
Project description:Mating is a complex process that causes many behavioral and physiological changes, but the factors triggering these changes and the underlying molecular processes are not well characterized. Honey bee queens provide a convenient system for dissecting these factors (e.g., physical manipulation, insemination volume, insemination substance) via instrumental insemination. We examined the effects of carbon dioxide (CO2), a commonly used anesthetic in instrumental insemination that causes changes similar to those observed after mating, and physical manipulation, which presumably mimics the act of copulation, on the brain transcriptional changes in honey bee queens. We found significant gene overlap between our study and previous mating studies in honey bee queens and Drosophila. This suggests that molecular pathways regulating the mating process are conserved across different mating regimes of honey bees as well as across insect orders.
Project description:This experiment evaluates quick (alarm) response to chilling in chilling-sensitive maize plants.<br>Maize inbred line cm109 were grown in optimal conditions until third leaf was fully developed. <br>At this stage plants were divided into three experimental variants: k0 - control plants, frozen<br>at the beginning of daylight, k4 - control plants kept in the same conditions and frozen after 4 hours<br>since beginning of daylight, c4 - plants kept in 14 deg. C for 4 hours since "dawn". At the mentioned<br>moments, leaves were harvested and frozen in liquid nitrogen for RNA isolation.
Project description:Hypoxia results in the changes in expression of many genes, the majority of which are mediated via the transcriptional activity of the hypoxia inducible factor (HIF) complex. However, other mechanisms of gene regulation by hypoxia are likely and include control of mRNA stability, regulation of mRNA translation and regulation mediated by micrornas. The aim of this study is to identify microRNAs which expression is regulated by hypoxia. We chose the breast cancer line MCF7 for study as we had previously characterised the expression of the components of the HIF system in that cell line and undertaken an extensive study of the gene expression profile in response to hypoxia, a prolyl hydroxylase inhibitor dimethyloxalylglycine and HIF-1a isoform manipulations (Eldvidge. G.P. et al. (2006) JBC, vol. 281, 22, 15215-15226).
Project description:Identification of the régulation pathways implied in adventitious root formation control in Arabidopsis etiolated seedlings. 2 mutants : a null allele and a weak allele of the ARGONAUTE gene. 4 repetitions in 2 pools for each sample.
Project description:Newly emerged adult workers (24 hours old) were infected with 50,000 Nosema apis spores in sucrose solution. Controls were fed sucrose. Workers were maintained in cages in an incubator and collected at 2 and 7 days post-infection. Fat body tissue was dissected (eviscerated abdomen) and whole genome expression in this tissue was compared across treatments and collection time points using microarrays.
Project description:In order to study the physiological consequences of a high-copper diet on hepatic gene expression, 6 mM CuCl2 was added to the drinking water for a period of 1 month. After this period, livers of seven control mice and eight copper-treated mice were isolated and were subjected to microarray analysis and copper measurements. The hepatic gene expression profile of copper-treated mice was compared to non-treated mice using a pooled reference.
Project description:Nine time points for microarray analysis were chosen to study early and late transcriptional responses in copper metabolism upon copper overload in HepG2 cells. Samples of copper-treated cells were hybridized using non-treated samples as a reference.
Project description:BACKGROUND: Social insects, such as honey bees, use molecular, physiological and behavioral responses to combat pathogens and parasites. The honey bee genome contains all of the canonical insect immune response pathways, and several studies have demonstrated that pathogens can activate expression of immune effectors. Honey bees also use behavioral responses, termed social immunity, to collectively defend their hives from pathogens and parasites. These responses include hygienic behavior (where workers remove diseased brood) and allo-grooming (where workers remove ectoparasites from nestmates). We have previously demonstrated that immunostimulation causes changes in the cuticular hydrocarbon profiles of workers, which results in altered worker-worker social interactions. Thus, cuticular hydrocarbons may enable workers to identify sick nestmates, and adjust their behavior in response. Here, we test the specificity of behavioral, chemical and genomic responses to immunostimulation by challenging workers with a panel of different immune stimulants (saline, Sephadex beads and Gram-negative bacteria E. coli). RESULTS: While only bacteria-injected bees elicited altered behavioral responses from healthy nestmates compared to controls, all treatments resulted in significant changes in cuticular hydrocarbon profiles. Immunostimulation caused significant changes in expression of hundreds of genes, the majority of which have not been identified as members of the canonical immune response pathways. Furthermore, several new candidate genes that may play a role in cuticular hydrocarbon biosynthesis were identified. Finally, we identified common genes regulated by pathogen challenge in honey bees and other insects, suggesting that immune responses are conserved at the molecular level. CONCLUSIONS: These studies suggest that honey bee genomic responses to immunostimulation are substantially broader than expected, and may mediate the behavioral changes associated with social immunity by orchestrating changes in chemical signaling.
Project description:comparison of the transcriptome of Columbia-0 WT and the trienoic fatty acid deficient mutant fad3-2/fad7-2/fad8 in control conditions.
Project description:comparison of the transcriptome of Columbia WT and the jasmonate deficient mutant aos (allene oxide synthase)in control conditions.