The local protein composition of chromatin is important for the regulation of transcription and other functions. By integrative analysis of genome-wide binding maps of 53 broadly selected chromatin components in Drosophila cells, we show that the genome is segmented into five principal chromatin types that are defined by unique, yet overlapping combinations of proteins, and form domains that can extend over >100 kb. We identify a novel repressive chromatin type that covers about half of the genome and lacks classic heterochromatin markers. Furthermore, transcriptionally active euchromatin consists of two distinct types that differ in molecular organization and H3K36 methylation, and regulate distinct classes of genes. Finally, we provide evidence that the different chromatin types act as guides that help to target DNA-binding factors to specific subsets of their recognition motifs. These results uncover basic principles of chromatin organization in a higher eukaryote. For this study, we generated whole-genome DamID binding profiles of 45 chromatin proteins in Drosophila Kc167 cells. Additionally, we perused published binding data of 8 chromatin proteins and generated a binding profile of one exogenous (yeast) DNA binding factor in Kc167 cells. On the same array platform, we obtained ChIP-on-chip profiles of histone H3, H1, H3K9me2, H3K27me3, H3K4me2, and H3K79me3. See supplementary files below. Gene expression was measured by RNA tag profiling. See GeneCounts supplementary file below. Overall design: [1] RNA tag sequences were optained on an Illumina GAII with the digital gene expression (DGE) module from duplicate RNA samples. [2] All DamID and ChIP experiments were done in Drosophila Kc167 cells in duplicate. Samples were hybridized to 380k NimbleGen arrays with 300 bp probe spacing. Every experiment was done in duplicate in the reverse dye orientation, where Dam-fusion material was hybridized over Dam-only material. For ChIP, immunoprecipitated material was hybridized over ChIP input material. 18 previously-submitted Samples were included in this study. 10 of 18 Samples have been renormalized for the GSE22069 study: GSM509087, GSM509088, GSM509089, GSM509090, GSM509091, GSM509092, GSM509093, GSM509094, GSM509095, GSM509096 New GSM accession numbers have been issued for these 10 samples. 8 of 18 Samples are identical in the original studies and in GSE22069: GSM423290, GSM423291, GSM423298, GSM423299, GSM493592, GSM493593, GSM509085, GSM509086 [3] The genomic locations in files GSE22069_norm_aggregated_discretized_tiling_arrays.txt and GSE22069_norm_aggregated_tiling_arrays.txt are relative to FlyBase release 5 (BDGP R5/dm3).
Systematic protein location mapping reveals five principal chromatin types in Drosophila cells.
Cell line, Treatment, Subject
View SamplesObesity has been shown to increase risk for cardiovascular disease and type-2 diabetes. In addition, it has been implicated in aggravation of neurological conditions such as Alzheimer's. In the model organism Drosophila melanogaster, a physiological state mimicking diet-induced obesity can be induced by subjecting fruit flies to a solid medium disproportionately higher in sugar than protein (HSD) or that has been supplemented with a rich source of saturated fat (HFD). These flies can exhibit increased circulating glucose levels, increased triglyceride content, insulin-like peptide resistance, and behavior indicative of neurological decline, such as decreased climbing ability. We subjected Oregon-R-C flies to variants of the HSD, HFD, or normal (control) diet (ND), followed by a total RNA extraction from fly heads of each diet group for the purpose of Poly-A selected RNA-Sequencing. We targeted at least 50 million paired-end, stranded reads of 75 basepairs in size, and analyzed 4 biological replicates per dietary condition. Our objective was to identify the effects of obesogenic diets on transcriptome patterns, how they differed between obesogenic diets, and identify genes that may relate to pathogenesis accompanying an obesity-like state. Functional annotation and enrichment analysis among genes whose expression was significantly affected by the obesogenic diets indicated an overrepresentation of genes associated with immunity, metabolism, and hemocyanin in the HFD group, and CHK, cell cycle activity, and DNA binding and transcription in the HSD group. Heat map representation of genes affected by both diets illustrated a large fraction of differentially expressed genes between the two diet groups. Diets high in sugar and diets high in fat both have notableeffects on the Drosophila transcriptome in head tissue. The impacted genes, and how they may relate to pathogenesis in the Drosophila obesity-like state, warrant further experimental investigation. Our results also indicate differences in the effects of the HFD and HSD on expression profiles in head tissue of Oregon-R-C flies, despite the reportedly similar phenotypic impacts of the diets. Overall design: Flies were reared on one of three diets (high fat, high sugar, or normal). 6 replicates, with twenty flies each, from each diet treatment were collected for a total of 18 samples. The heads of the flies were then obtained, and RNA extracted from each of those samples. 4 of the RNA samples from each diet group (12 samples total) were sequenced.
RNA-Sequencing of <i>Drosophila melanogaster</i> Head Tissue on High-Sugar and High-Fat Diets.
Specimen part, Subject
View SamplesGene expression of the F1 Hybrids between two soybean parents (NMS4-44-329 and N7103) were compared. Changes in gene expression were correlated with agronomic traits. Overall design: RNA was isolated from leaf matrial harvested from the field in july of 2015. Four replicates were grown at two location in a random complete block design. Each samples is represented from three or four replications form each location
Changes in gene expression between a soybean F1 hybrid and its parents are associated with agronomically valuable traits.
Specimen part, Subject
View SamplesThe outcome of infections with Toxoplasma gondii in humans is dependent in part on the genetic makeup of the infecting organism. Recent studies have indicated that most infecting Toxoplasma organisms fall into 1 of 3 canonical lineages. Previous studies have investigated the effects of Toxoplasma on its host cell transcriptome. Little is known, however, about the effects of three canonical lineages on brain cells, the principal site of parasite lifelong persistence. In this study, we examined the transcriptional profile of human neuroepithelioma cells in response to T. gondii infection using microarray analysis to characterize the strain-specific host cell response to 3 canonical T. gondii strains. We found that the extent of the expression changes varied considerably among the three strains. Neuroepithelial cells infected with type I exhibited the most differential gene expression, whereas type II infected cells had a substantially smaller number of genes which were differentially expressed. Cells infected with type III exhibited intermediate effects on gene expression. The three strains also differed in the individual genes and gene pathways which were altered following cellular infection. For example, gene ontology (GO) analysis indicated that type I infection largely affects genes related to central nervous system while type III infection largely alters genes which affect nucleotide metabolism; type II infection does not alter expression of a clearly defined set of genes. Moreover, Ingenuity pathway analysis (IPA) revealed the sophistication of different strain in its interactions with the host. These differences may explain some of the variation in the neurobiological effects of different strains of Toxoplasma on infected individuals.
Differential effects of three canonical Toxoplasma strains on gene expression in human neuroepithelial cells.
Cell line
View SamplesSmyd3 is a histone methyltransferase implicated in tumorigenesis. Here we show that Smyd3 expression in mice is required but not sufficient for chemically induced liver and colon cancer formation. In these organs Smyd3 is functioning in the nucleus as a direct transcriptional activator of several key genes involved in cell proliferation, epithelial-mesenchymal transition, JAK/Stat3 oncogenic pathways, as well as of the c-myc and b-catenin oncogenes. Smyd3 specifically interacts with H3K4Me3-modified histone tails and is recruited to the core promoter regions of many but not all active genes. Smyd3 binding density on target genes positively correlates with increased RNA Pol-II density and transcriptional outputs. The results suggest that Smyd3 is an essential transcriptional potentiator of a multitude of cancer-related genes. Overall design: Standard Smyd3-deficient (Smyd3-KO) mice were generated using gene-trap ES cell clones (AS0527 from International Gene Trap Consortium), in which a selection cassette, containing the splice acceptor site from mouse EN2 exon 2 followed by the beta-galactosidase and neomycin resistance gene fusion gene and the SV40 polyadenylation sequence was inserted into the 5th intron of the Smyd3 gene. The resulting mice were devoid of Smyd3 mRNA and protein in all tissues, including liver and colon. For the generation of Smyd3-Tg mice the open reading frame of the mouse Smyd3 cDNA, which contained 3 Flag epitopes at the 3’ end was inserted into the StuI site of the pTTR1-ExV3 plasmid (Yan et al, 1990). The 6.8 kb HindIII fragment containing the mouse transthyretin enhancer/promoter, intron 1, Smyd3 cDNA, three Flag epitopes and SV40 poly-A site was used to microinject C57Bl/6 fertilized oocytes. Founder animals were identified by Southern blotting and crossed with F1 mice to generate lines. Specific overexpression in the liver was tested by RT-PCR analysis in different tissues.
Smyd3 Is a Transcriptional Potentiator of Multiple Cancer-Promoting Genes and Required for Liver and Colon Cancer Development.
No sample metadata fields
View SamplesTransactive response DNA-binding protein of 43 kDa (TDP-43), a heterogeneous nuclear ribonucleoprotein (hnRNP) with diverse activities, is a common denominator in several neurodegenerative disorders including amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD). Orthologs of TDP-43 exist from mammals to invertebrates, but their functions in lower organisms remain poorly understood. Here we systematically studied mutant Caenorhabditis elegans lacking the nematode TDP-43 ortholog, TDP-1. To understand the global gene expression regulation induced by the loss of tdp-1, the C. elegans transcriptomes were compared between the N2 WT animals and the tdp-1(ok803lf) mutant. Transcriptional profiling demonstrated that the loss of TDP-1 altered expression of genes functioning in RNA processing and protein folding. These results suggest that the C. elegans TDP-1 as an RNA-processing protein may have a role in the regulation of protein homeostasis and aging.
Caenorhabditis elegans RNA-processing protein TDP-1 regulates protein homeostasis and life span.
No sample metadata fields
View SamplesInvestigation of gene expression profiles among patients with COPD frequent exacerbations and to find gene targets as predictors of exacerbations
Altered gene expression in blood and sputum in COPD frequent exacerbators in the ECLIPSE cohort.
Sex, Age, Specimen part
View SamplesWe report RNA sequencing data from tenocytes treated with IGF1. Tenocytes were obtained from the tail tendons of adult C57Bl/6 mice via collagenase digestion. Tenocytes were grown to 60% confluence, and then treated with 100ng/mL of recombinant IGF1 for a period of 0, 1, 2, 6, or 24 hours. Experiments were conducted in quadruplicate. RNA was isolated and prepared for RNA sequencing. Overall design: Differential expression of mRNAs were evaluated from tenocytes isolated from tail tendons of adult wild type C57Bl/6 mice that were treated with recombinant IGF1 for 0, 1, 2, 6, and 24 hours.
Insulin-like growth factor 1 signaling in tenocytes is required for adult tendon growth.
Specimen part, Cell line, Subject
View SamplesRegulation of genes in shoots and roots and Arabidopsis in response to Zn-deficiency in wild-type and hma2 hma4 mutants plants
Systemic Upregulation of MTP2- and HMA2-Mediated Zn Partitioning to the Shoot Supplements Local Zn Deficiency Responses.
Age, Specimen part
View SamplesTranscription and pre-mRNA alternative splicing are highly regulated processes that play major roles in modulating eukaryotic gene expression. It is increasingly apparent that other pathways of RNA metabolism, including small RNA biogenesis, can regulate these processes. However, a direct link between alternative pre- mRNA splicing and small RNA pathways has remained elusive. Here we show that the small RNA pathway protein Argonaute-2 (Ago-2) regulates alternative pre-mRNA splicing patterns of specific transcripts in the Drosophila nucleus using genome-wide methods in conjunction with RNAi in cell culture and Ago-2 deletion or catalytic site mutations in Drosophila adults. Moreover, we show that nuclear Argonaute-2 binds to specific chromatin sites near gene promoters and negatively regulates the transcription of the Ago-2-associated target genes. These transcriptional target genes are also bound by Polycomb group (PcG) transcriptional repressor proteins and change during development, implying that Ago-2 may regulate Drosophila development. Impor- tantly, both of these activities were independent of the catalytic activity of Ago-2, suggesting new roles for Ago-2 in the nucleus. Finally, we determined the nuclear RNA-binding profile of Ago-2, found it bound to several splicing target transcripts, and identified a G-rich RNA-binding site for Ago-2 that was enriched in these transcripts. These results suggest two new nuclear roles for Ago-2: one in pre-mRNA splicing and one in transcriptional repression. Overall design: 2 Ago2 mutants, 51B and V966M, heterozygotes and homozygotes of both each sequenced in duplicate
Two new and distinct roles for Drosophila Argonaute-2 in the nucleus: alternative pre-mRNA splicing and transcriptional repression.
Sex, Subject
View Samples