Drosophila melanogaster
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA138531 | ENA |
REPOSITORIES: ENA
Similar Datasets
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
2008-03-20 | GSE9639 | GEO
Project description:Copy number variants (CNVs) reshape gene structure, modulate gene expression, and contribute to significant phenotypic variation. Previous studies have revealed CNV patterns in natural populations of Drosophila melanogaster and suggested that selection and mutational bias shape genomic patterns of CNV. While previous CNV studies focused on heterogeneous strains, here we established a number of second-chromosome substitution lines to uncover CNV characteristics when homozygous. The percentage of genes harboring CNVs is higher than found in previous studies. More CNVs are detected in homozygous than heterozygous substitution strains, suggesting the comparative genomic hybridization arrays underestimate CNV owing to heterozygous masking. We incorporated previous gene expression data collected from some of the same substitution lines to investigate relationships between CNV gene dosage and expression. Most genes present in CNVs show no evidence of increased or diminished transcription, and the fraction of such dosage-insensitive CNVs is greater in heterozygotes. More than 70% of the dosage-sensitive CNVs are recessive with undetectable effects on transcription in heterozygotes. A deficiency of singletons in recessive dosage-sensitive CNVs supports the hypothesis that most CNVs are subject to negative selection. On the other hand, relaxed purifying selection might account for the higher number of protein-protein interactions in dosage insensitive CNVs than in dosage-sensitive CNVs. Dosage-sensitive CNVs that are up-regulated and down-regulated coincide with copy number increases and decreases. Our results help clarify the relation between CNV dosage and gene expression in the D. melanogaster genome.
2011-03-03 | GSE27632 | GEO
Project description:Copy number variants (CNVs) reshape gene structure, modulate gene expression, and contribute to significant phenotypic variation. Previous studies have revealed CNV patterns in natural populations of Drosophila melanogaster and suggested that selection and mutational bias shape genomic patterns of CNV. While previous CNV studies focused on heterogeneous strains, here we established a number of second-chromosome substitution lines to uncover CNV characteristics when homozygous. The percentage of genes harboring CNVs is higher than found in previous studies. More CNVs are detected in homozygous than heterozygous substitution strains, suggesting the comparative genomic hybridization arrays underestimate CNV owing to heterozygous masking. We incorporated previous gene expression data collected from some of the same substitution lines to investigate relationships between CNV gene dosage and expression. Most genes present in CNVs show no evidence of increased or diminished transcription, and the fraction of such dosage-insensitive CNVs is greater in heterozygotes. More than 70% of the dosage-sensitive CNVs are recessive with undetectable effects on transcription in heterozygotes. A deficiency of singletons in recessive dosage-sensitive CNVs supports the hypothesis that most CNVs are subject to negative selection. On the other hand, relaxed purifying selection might account for the higher number of protein-protein interactions in dosage insensitive CNVs than in dosage-sensitive CNVs. Dosage-sensitive CNVs that are up-regulated and down-regulated coincide with copy number increases and decreases. Our results help clarify the relation between CNV dosage and gene expression in the D. melanogaster genome. To determine copy number variation, the genomic DNA from five homozygous and two heterozygous second chromosome substitution lines were extracted and compared to another second chromosome substitution line. Gene expression levels can be referred to at Series GSE12191 (Lemos et al. (2008) PMID:18791071).
2011-03-03 | E-GEOD-27632 | biostudies-arrayexpress
Project description:Naturally occurring copy-number polymorphism in Drosophila melanogaster
| PRJNA103499 | ENA
Project description:Genome sequencing of six Drosophila melanogaster lines for the study of copy number variations
| PRJNA282433 | ENA
Project description:Parallel Geographic Variation in Drosophila melanogaster
| PRJNA237820 | ENA
Project description:The role natural selection plays in governing the locations and early evolution of copy number mutations remains largely unexplored. Here we employ high-density full-genome tiling arrays to create a fine-scale genomic map of copy number polymorphisms (CNPs) in Drosophila melanogaster. We inferred a total of 2,658 independent CNPs, 56% of which overlap genes. These include CNPs likely to be under positive selection, most notably high frequency duplications encompassing toxin-response genes. The locations and frequencies of CNPs are strongly shaped by purifying selection with deletions under stronger purifying selection than duplications. Among duplications, those overlapping exons or introns and those falling on the X-chromosome seem to be subject to the strongest purifying selection. In order to characterize copy number polymorphisms (CNPs) in Drosophila malanogaster, we applied comparative genome hybridization (CGH) using tiling arrays covering the full euchromatic genome of Drosophila melanogaster. We inferred copy number changes with a Hidden Markov Model (HMM) that returned the posterior probabilities for copy number by comparing DNA hybridization intensities between natural isolates and the reference genome strain. Training data for copy number changes were obtained via hybridization with a line known to contain a ~200kb homozygous duplication and from a set of 52 validated homozygous deletions. The probabilities of mutation were parsed to make CNP calls. Key words: comparative genomic hybridization, CGH, copy number polymorphism, CNP, copy number variation, CNV, duplication, deletion
2008-06-06 | GSE11326 | GEO
Project description:To investigate the effect of sex on within- and between-population variation in gene expression, we performed a microarray analysis of adult females from 16 strains of Drosophila melanogaster, including eight strains from the putative ancestral range in sub-Saharan Africa and eight strains from a European population. The results were compared to those of a previous study of adult male gene expression variation among the same strains (GSE8843).
2010-12-23 | GSE23662 | GEO
Project description:Drosophila melanogaster strain:SIM Variation
| PRJNA257179 | ENA