Project description:One of the critical substances that mammals highly regulate via the respiratory, cardiovascular and neurologic systems is O2. Both low and high O2 levels can induce major morbidities as well as mortality. Indeed, O2 has been often considered as both an elixir and a poison in humans. In current study, we have used an experimental selection approach to generate Drosophila strains that are tolerant to severe hyperoxic environment. Gene expression profiling is then applied to investigate the mechanisms underlying hyperoxia tolerance in the newly generated strains. 27 isogenic D. melanogaster Lines were pooled and following long-term selection over generations with increased oxygen level in the culture environment. The differences in gene expression were compared between adapted flies and generation matched naive controls by microarray.
Project description:Transcriptional profiling of 3 day old virgin male and female adults comparing control male Drosophila melanogaster (MDM) versus male D sechellia (MDS) and comparing control female Drosophila melanogaster (FDM) versus female D sechellia (FDS). Goal was to determine why D sechellia is tolerant to octanoïc acid, the major toxic compound of Morinda citrifolia fruit
Project description:It is well appreciated that reactive oxygen species (ROS) are deleterious to mammals, including humans, especially when generated in abnormally large quantities from cellular metabolism. Whereas the mechanisms leading to the production of ROS are rather well delineated, the mechanisms underlying tissue susceptibility or tolerance to oxidant stress remain elusive. Through an experimental selection over many generations, we have previously generated Drosophila melanogaster flies that tolerate tremendous oxidant stress and have shown that the family of antimicrobial peptides (AMP) is over-represented in these tolerant flies. Furthermore, we have also demonstrated that overexpression of even one AMP at a time (e.g. Diptericin) allows wild type flies to survive much better in hyperoxia. In the current study, we used a number of experimental approaches to investigate the potential mechanisms underlying hyperoxia tolerance in flies with antimicrobial peptide overexpression. We demonstrate that flies with Diptericin overexpression resist oxidative stress by increasing antioxidant enzyme activities and preventing an increase in ROS level after hyperoxia. Depleting the GSH pool using buthionine sulfoximine limits fly survival, thus confirming that enhanced survival observed in these flies is related to improved redox homeostasis. We conclude that a) AMPs play an important role in tolerance to oxidant stress; b) overexpression of Diptericin changes the cellular redox balance between oxidant and antioxidant, and c) this change in redox balance plays an important role in survival in hyperoxia. Expression profiles of Drosophila melanogaster with anti-microbial peptide over-expression (experimental sample; n=3) and controls (UAS-AMP alone not crossed to da-GAL4; n=3) were determined using Affymetrix Drosophila Genome 2.0 Arrays.
Project description:One of the critical substances that mammals highly regulate via the respiratory, cardiovascular and neurologic systems is O2. Both low and high O2 levels can induce major morbidities as well as mortality. Indeed, O2 has been often considered as both an elixir and a poison in humans. In current study, we have used an experimental selection approach to generate Drosophila strains that are tolerant to severe hyperoxic environment. Gene expression profiling is then applied to investigate the mechanisms underlying hyperoxia tolerance in the newly generated strains.
Project description:It is well appreciated that reactive oxygen species (ROS) are deleterious to mammals, including humans, especially when generated in abnormally large quantities from cellular metabolism. Whereas the mechanisms leading to the production of ROS are rather well delineated, the mechanisms underlying tissue susceptibility or tolerance to oxidant stress remain elusive. Through an experimental selection over many generations, we have previously generated Drosophila melanogaster flies that tolerate tremendous oxidant stress and have shown that the family of antimicrobial peptides (AMP) is over-represented in these tolerant flies. Furthermore, we have also demonstrated that overexpression of even one AMP at a time (e.g. Diptericin) allows wild type flies to survive much better in hyperoxia. In the current study, we used a number of experimental approaches to investigate the potential mechanisms underlying hyperoxia tolerance in flies with antimicrobial peptide overexpression. We demonstrate that flies with Diptericin overexpression resist oxidative stress by increasing antioxidant enzyme activities and preventing an increase in ROS level after hyperoxia. Depleting the GSH pool using buthionine sulfoximine limits fly survival, thus confirming that enhanced survival observed in these flies is related to improved redox homeostasis. We conclude that a) AMPs play an important role in tolerance to oxidant stress; b) overexpression of Diptericin changes the cellular redox balance between oxidant and antioxidant, and c) this change in redox balance plays an important role in survival in hyperoxia.
Project description:Identification of the interaction partners of the protein ecdysoneless (Ecd) in Drosophila melanogaster S2 cells as well as profiling of the changes in binding for mutant, truncated Ecd del34 protein.