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
Project description:Transcriptional profiling of Drosophila melanogaster 2nd chromosome substitution lines; Background chromosomes are identical across lines; 2nd chromosomes are different across line and can be homozygous or heterozygous within each line Keywords: Natural variation
Project description:Absolute (molar) quantification determines proteins stoichiometry in complexes, networks and metabolic pathways. We employed MS Western workflow to determine molar abundances of proteins critical for morphogenesis and phototransduction (PT) in eyes of Drosophila melanogaster using a single chimeric 264 kDa protein standard that covers, in total, 197 peptides from 43 proteins. Each protein was independently quantified with 2 to 4 proteotypic peptides with the coefficient of variation of less than 15 %, better than 1000-fold dynamic range and sub-femtomole sensitivity. We determined molar abundances and stoichiometric ratios of the components of the PT machinery and the rhabdomere, and how they are changing when rhabdomere morphogenesis is perturbed by genetic manipulation of the evolutionary conserved gene crumbs (crb).
Project description:Thermal acclimation study on Drosophila melanogaster reared at 3 different temperatures (12, 25, and 31oC). The proteomic profiles of D. melanogaster under these different temperatures were analyzed and compared using label-free tandem mass spectrometry.