Project description:Genome-wide expression analysis comparison with and without ionizing radiation in p53 mutant and wild type Drosophila larvae Genome-wide expression analysis comparison with and without ionizing radiation in p53 mutant (p53^5A-1-4) and wild type (y^1 w^1118) Drosophila third instar larvae. 4000R of X-rays used in IR-treated Drosophila. Analyzed 2hr and 18hr after exposure with age-matched larvae in non-treated controls.
Project description:Gene expression changes in response to aging compared to heat stress, oxidative stress and ionizing radiation in Drosophila melanogaster
Project description:Gene expression changes in response to aging, hyperoxia, hydrogen peroxide, ionizing radiation, and heat stress were compared using microarrays. While aging shared features with each stress, aging was more similar to the stresses most associated with oxidative stress (hydrogen peroxide, hyperoxia, ionizing radiation) than to heat stress. Aging is associated with down-regulation of numerous mitochondrial genes, including electron-transport-chain (ETC) genes and mitochondrial metabolism genes, and a sub-set of these changes was also observed upon hydrogen peroxide stress and ionizing radiation stress. Aging shared the largest number of gene expression changes with hyperoxia. The extensive down-regulation of mitochondrial and ETC genes during aging is consistent with an aging-associated failure in mitochondrial maintenance, which may underlie the oxidative stress-like and proteotoxic stress-like responses observed during aging. Thirty five sample of RNA including Stress Controls (4 replicates), Heat Stress (3 replicates), Ionizing Radiation (4 replicates), Sugar (4 replicates), Hydrogen Peroxide (4 replicates), Young Controls (6 replicates) , Hyperoxia (6 replicates) and Old (4 replicates) adult Drosophila were analysed by Affymetrix microarrays. Stress Controls were used as controls for Heat Stress, Ionizing Radiation, Sugar and Hydrogen Peroxide samples. Young Controls were used as controls for Hyperoxia and Old samples. All flies were male progeny of a cross between Oregon-R wildtype and transgenic strain w[1118];P{w+ rtTA}(3)[E2]/ TM3. Flies lacking the balancer but bearing the transgene were used.
Project description:The innate immune response of insects relies on several humoral and cellular mechanisms that require the activation of circulating proteases in the hemolymph to be functional. Here, we analyzed the gelatinase and caseinase activities of Drosophila larval hemolymph under normal and pathogenic conditions (bacterial lipopolysaccharides or endoparasitoid Leptopilina boulardi) using in gel zymography. Gelatinase activity was more intense than caseinase activity and qualitative and quantitative variations were observed between D. melanogaster strains and Drosophila species. Mass spectrometry identified a large number of serine proteases in gel bands equivalent to the major gelatinase and caseinase bands and of these, the most abundant and redundant were Tequila and members of the Jonah and Trypsin protease families. However, hemolymph from Tequila null mutant larvae showed no obvious changes in zymographic bands. Nor did we observe any significant changes in hemolymph gelatinases activity 24 h after injection of bacterial lipopolysaccharides or after oviposition by endoparasitoid wasps. These data confirmed that many serine proteases are present in Drosophila larval hemolymph but those with gelatinase and caseinase activity may not change drastically during the immune response.
Project description:We investigate the biological effects of radiation using Drosophila Melanogaster as a model organism, focusing on gene expression and lifespan analysis to determine the effect of different radiation doses. Our results support a threshold effect in response to radiation: no effect on lifespan and no permanent effect on gene expression is seen at doses below 10,000 Roentgens.