Project description:Chromosomal and segmental aneuploidies are usually lethal or common features of cancer cells and variety of disease, but little is known about how copy number relates to gene expression. Drosophila males have a single X chromosome and two sets of autosomes, but X chromosome and autosome transcripts are equally abundant. This 2-fold increase in X chromosome gene expression requires a dosage compensation complex (MSL) that acetylates histone 4 at lysine 16 (H4AcK16). To determine the contribution of general buffering and MSL to X chromosome dosage compensation, we analyzed genome-wide copy number, expression and histone modification pattern in male Drosophila S2 cells with and without MSL. Keywords: Gene Regulation Study, genomic analyses
Project description:Aneuploidy, i.e., variation in the number of individual chromosomes (chromosomal aneuploidy) or chromosome segment (segmental aneuploidy) is associated with developmental abnormalities and reduced fitness in all species examined, is the leading cause of miscarriages and mental retardations and a hallmark of cancer. Despite their documented importance in disease the effects of aneuploidies on the transcriptome remains largely unknown. Here we have examined the expression output in seven deficiency heterozygotes as single deficiencies and in all pairwise combinations. The results show that genes in one copy are buffered, i.e., are expressed above the expected 50% expression level compared to wild type and the buffering is general and not influenced by additional haploid regions. Long genes are significantly better buffered than short genes and our analysis suggests that gene length is the primary determinant for the degree of buffering. For short genes the degree of buffering depends on expression level and expression pattern. Furthermore, the results show that in deficiency heterozygotes the expression of genes involved in proteolysis is enhanced and negatively correlates with the degree of buffering. Our results suggest that proteolysis is a general response induced by aneuploidy.
Project description:Aneuploidy, i.e., variation in the number of individual chromosomes (chromosomal aneuploidy) or chromosome segment (segmental aneuploidy) is associated with developmental abnormalities and reduced fitness in all species examined, is the leading cause of miscarriages and mental retardations and a hallmark of cancer. Despite their documented importance in disease the effects of aneuploidies on the transcriptome remains largely unknown. Here we have examined the expression output in seven deficiency heterozygotes as single deficiencies and in all pairwise combinations. The results show that genes in one copy are buffered, i.e., are expressed above the expected 50% expression level compared to wild type and the buffering is general and not influenced by additional haploid regions. Long genes are significantly better buffered than short genes and our analysis suggests that gene length is the primary determinant for the degree of buffering. For short genes the degree of buffering depends on expression level and expression pattern. Furthermore, the results show that in deficiency heterozygotes the expression of genes involved in proteolysis is enhanced and negatively correlates with the degree of buffering. Our results suggest that proteolysis is a general response induced by aneuploidy. We prepared total RNA from flies heterozygous for seven different deletions, Df(3R)ED10953, Df(2L)ED4559, Df(2R)ED1770, Df(2R)ED1612, Df(2L)ED3, Df(3R)ED5071 or Df(3R)ED7665 in two or three single biological replicates or in pairwise combinations, as well as from six biological replicates of wild type control flies.
Project description:Chromosomal and segmental aneuploidies are usually lethal or common features of cancer cells and variety of disease, but little is known about how copy number relates to gene expression. Drosophila males have a single X chromosome and two sets of autosomes, but X chromosome and autosome transcripts are equally abundant. This 2-fold increase in X chromosome gene expression requires a dosage compensation complex (MSL) that acetylates histone 4 at lysine 16 (H4AcK16). To determine the contribution of general buffering and MSL to X chromosome dosage compensation, we analyzed genome-wide copy number, expression and histone modification pattern in male Drosophila S2 cells with and without MSL. Keywords: Gene Regulation Study, genomic analyses RNA-seq and microarray were performed in Drosophila non-treated or RNAi treated S2 cells. Two biological replicates were used for expression profile. DNA-seq and CGH were performed (CGH data forthcoming) to check the copy number variation in S2 cells. Chromatin immunoprecipitations were performed in Drosophila non-treated or RNAi treated S2 cells with different histone modification antibodies. At least three biological replicates were performed for each antibody and treatment.
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.