Project description:High throughput seqeuncing of small RNAs (PAGE isolated from total RNA or Argonaute immunoprecipitates) from Drosophila melanogaster using the Illumina platform. Adapter ligation requires 5' monophosphate and 3' OH. Full analysis of all libraries in this set is published (Czech B. et al. 2008), leading to the description of endogenous siRNAs in flies. Keywords: Solexa sequences
Project description:Transfer RNAs (tRNAs) are vital in determining the specificity of translation. Mutations in tRNAs can result in the mis-incorporation of amino acids into nascent polypeptides in a process known as mistranslation. Here, our goal was to test the impacts of different types of mistranslation in the model organism Drosophila melanogaster, as impact of mistranslation depends on the type of amino acid substitution. We created two fly lines - one expressing a serine tRNA variant with valine anticodon and the other with a serine tRNA variant with a threonine anticodon. Using mass spectrometry, we measure the amount of mistranslation at various points in fly development.
Project description:Knowledge of the genetic mechanisms underlying among-individual variation in response to environmental variables or treatment is important in many research areas; for example, acquaintance of the set of causal genetic variants for drug responses could revolutionize the field of personalized medicine. We used Drosophila melanogaster to investigate the genetic signature underlying variability in response to methylphenidate (MPH), a drug used in treatment of ADHD. We exposed a wild type D. melanogaster population to MPH or a control treatment and observed an increase in locomotor activity in individuals exposed to MPH. Whole-genome transcriptomic analyses revealed that the behavioral response to MPH was associated with abundant gene expression alterations. To confirm these patterns in a different genetic background, and to further advance knowledge on the genetic signature of drug response variability, we used a system of sequenced inbred lines, the Drosophila Genetic Reference Panel. Utilizing an integrative genomic approach we incorporated the transcriptomic data as well as gene interactions into the genomic analyses, from which we identified putative candidate genes for drug response variability. We successfully validated 70% of the investigated putative candidate genes by gene expression knockdown. Furthermore, we showed that MPH has cross generational behavioral- and transcriptomic effects.
Project description:Thomas Hunt Morgan and colleagues identified variation in gene copy number in Drosophila in the 1920s and 1930s and linked such variation to phenotypic differences [Bridges, C. B. (1936) Science 83, 210]. Yet the extent of variation in the number of chromosomes, chromosomal regions, or gene copies, and the importance of this variation within species, remain poorly understood. Here, we focus on copy-number variation in Drosophila melanogaster. We characterize copy-number polymorphism (CNP) across genomic regions, and we contrast patterns to infer the evolutionary processes acting on this variation. Copy-number variation in D. melanogaster is non-randomly distributed, presumably due to a mutational bias produced by tandem repeats or other mechanisms. Comparisons of coding and noncoding CNPs, however, reveal a strong effect of purifying selection in the removal of structural variation from functionally constrained regions. Most patterns of CNP in D. melanogaster suggest that negative selection and mutational biases are the primary agents responsible for shaping structural variation. Keywords: comparative genomic hybridization