Project description:These arrays were done in the context of a study to probe gene expression variation across Y-chromosome substitution lines of Drosophila melanogaster Keywords: polymorphism, evolution, chromosome substitution
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:These arrays were done in the context of a study to probe gene expression variation across Y-chromosome substitution lines of Drosophila melanogaster Keywords: polymorphism, evolution, chromosome substitution This series contains all the arrays and designs described in Lemos et al.
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).
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 Loop design with 8 genotypes
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.