Ludwig Institute/UCSD ENCODE project March 2007 Release
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
SUBMITTER: R Hawkins
PROVIDER: E-GEOD-7118 | biostudies-arrayexpress |
REPOSITORIES: biostudies-arrayexpress
Publications
Histone modifications at human enhancers reflect global cell-type-specific gene expression.
Heintzman Nathaniel D ND Hon Gary C GC Hawkins R David RD Kheradpour Pouya P Stark Alexander A Harp Lindsey F LF Ye Zhen Z Lee Leonard K LK Stuart Rhona K RK Ching Christina W CW Ching Keith A KA Antosiewicz-Bourget Jessica E JE Liu Hui H Zhang Xinmin X Green Roland D RD Lobanenkov Victor V VV Stewart Ron R Thomson James A JA Crawford Gregory E GE Kellis Manolis M Ren Bing B
Nature 20090318 7243
The human body is composed of diverse cell types with distinct functions. Although it is known that lineage specification depends on cell-specific gene expression, which in turn is driven by promoters, enhancers, insulators and other cis-regulatory DNA sequences for each gene, the relative roles of these regulatory elements in this process are not clear. We have previously developed a chromatin-immunoprecipitation-based microarray method (ChIP-chip) to locate promoters, enhancers and insulators ...[more]
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Project description:The readout of genome information is controlled by transcriptional regulatory elements, but a comprehensive view of the combinatorial control by these DNA sequences, which bind regulatory protein and/or the modified histones in regulating gene transcription, is clearly preliminary. We have developed an experimental strategy for comprehensive determination of such functional elements in human DNA. This strategy involves the application of genome-wide location analysis, also known as ChIP-chip, to a panel of well-characterized regulatory proteins and histones with specific modifications, known to generally associate with transcriptional regulatory elements in vivo. Identification of their genomic binding sites will allow us to determine the sequence features in the human genome that carry out transcriptional regulatory function. We have designed and produced DNA microarrays to represent all the non-repetitive sequences in the 30 million basepair ENCODE regions of the human genome to map various types of transcriptional regulatory elements in three model cell types. We have identified promoters by mapping the genomic sequences associated with RNA polymerase II and the general transcription factor TFIID in cells, enhancer elements by mapping the genomic sequences associated with transcriptional co-activators and enhancer-specific chromatin modifications, and insulators by mapping the genomic sequences associated with the insulator binding protein CTCF. The raw microarray results are released periodically prior to publication. Keywords: ChIP-chip ENCODE ChIP-chip analyses were performed for various transcription factors and chromatin modifications in various cell types. Details to be described in publications. Ren B, Glass CK, Rosenfeld MG, Webster N, Ching KA, Harp L, Ye Z, Stuart RK, Calcar SV, Kim TH, Hawkins RD, Hon G, Barrera LO, Luna R, Wang K
2010-05-15 | E-GEOD-8887 | biostudies-arrayexpress
Project description:The readout of genome information is controlled by transcriptional regulatory elements, but a comprehensive view of the combinatorial control by these DNA sequences, which bind regulatory protein and/or the modified histones in regulating gene transcription, is clearly preliminary. We have developed an experimental strategy for comprehensive determination of such functional elements in human DNA. This strategy involves the application of genome-wide location analysis, also known as ChIP-chip, to a panel of well-characterized regulatory proteins and histones with specific modifications, known to generally associate with transcriptional regulatory elements in vivo. Identification of their genomic binding sites will allow us to determine the sequence features in the human genome that carry out transcriptional regulatory function. We have designed and produced DNA microarrays to represent all the non-repetitive sequences in the 30 million basepair ENCODE regions of the human genome to map various types of transcriptional regulatory elements in three model cell types. We have identified promoters by mapping the genomic sequences associated with RNA polymerase II and the general transcription factor TFIID in cells, enhancer elements by mapping the genomic sequences associated with transcriptional co-activators and enhancer-specific chromatin modifications, and insulators by mapping the genomic sequences associated with the insulator binding protein CTCF. The raw microarray results are released periodically prior to publication. Keywords: ChIP-chip ENCODE ChIP-chip analyses were performed for various transcription factors and chromatin modifications in various cell types. Details to be described in publications. Ren B, Glass CK, Rosenfeld MG, Webster N, Ching KA, Harp L, Ye Z, Stuart RK, Calcar SV, Kim TH, Hawkins RD, Hon G, Barrera LO, Luna R, Wang K
2007-06-01 | E-GEOD-7872 | biostudies-arrayexpress
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2009-08-31 | E-GEOD-17070 | biostudies-arrayexpress
Project description:Anopheles gambiae mosquitoes exhibit an endophilic, nocturnal blood feeding behavior. Despite the importance of light as a regulator of malaria transmission, our knowledge on the molecular interactions between environmental cues, the circadian oscillators and the host seeking and feeding systems of the Anopheles mosquitoes is limited. In the present study, we show that the blood feeding behavior of mosquitoes is under circadian control and can be modulated by light pulses, both in a clock dependent and in an independent manner. Short light pulses (~2-5 min) in the dark phase can inhibit the blood-feeding propensity of mosquitoes momentarily in a clock independent manner, while longer durations of light stimulation (~1-2 h) can induce a phase advance in blood-feeding propensity in a clock dependent manner. The temporary feeding inhibition after short light pulses may reflect a masking effect of light, an unknown mechanism which is known to superimpose on the true circadian regulation. Nonetheless, the shorter light pulses resulted in the differential regulation of a variety of genes including those implicated in the circadian control, suggesting that light induced masking effects also involve clock components. Light pulses (both short and longer) also regulated genes implicated in feeding as well as different physiological processes like metabolism, transport, immunity and protease digestions. RNAi-mediated gene silencing assays of the light pulse regulated circadian factors timeless, cryptochrome and three takeout homologues significantly up-regulated the mosquito's blood-feeding propensity. In contrast, gene silencing of light pulse regulated olfactory factors down-regulated the mosquito's propensity to Our study suggests that the mosquitoâs feeding behavior is under circadian control. Long and short light pulses can induce inhibition of blood-feeding through circadian and unknown mechanisms, respectively, that involve chemosensory factors. A series of assays were performed to assess transcriptomic changes in mosquitoes upon light stimulation and blood feeding in order to assess relationships between photic stimulation and modulation of feeding behavior.
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Project description:The complete genome sequence of the P. vivax Sal-1 strain allowed the design of a first version array representing 1 oligo/2 kb of coding sequences (http://zblab.sbs.ntu.edu.sg/vivax/index.html). Here, proof-of-principle experiments using total RNA of parasites obtained from the Sal-1 strain, from P. falciparum and from parasites obtained directly from two human patients are presented. To determine the extent of cross-hybridization of P. falciparum with P. vivax, and to determine overlaps in expression profiles of the P. vivax Sal1 monkey-adapted strain vs wild isolates, single dual hybridization analyses were performed.
2008-04-12 | E-GEOD-11075 | biostudies-arrayexpress
Project description:Background: The mosquito Anopheles gambiae is a major vector of human malaria. Increasing evidence indicates that blood cells (hemocytes) comprise an essential arm of the mosquito innate immune response against both bacteria and malaria parasites. To further characterize the role of hemocytes in mosquito immunity, we undertook the first genome-wide transcriptomic analyses of adult female An. gambiae hemocytes following infection by two species of bacteria and a malaria parasite. Results: We identified 4047 genes expressed in hemocytes, using An. gambiae genome-wide microarrays. While 279 transcripts were significantly enriched in hemocytes relative to whole adult female mosquitoes, 959 transcripts exhibited immune challenge-related regulation. The global transcriptomic responses of hemocytes to challenge with different species of bacteria and/or different stages of malaria parasite infection revealed discrete, minimally overlapping, pathogen-specific signatures of infection-responsive gene expression; 105 of these represented putative immunity-related genes including anti-Plasmodium factors. Of particular interest was the specific co-regulation of various members of the Imd and JNK immune signaling pathways during malaria parasite invasion of the mosquito midgut epithelium. Conclusion: Our genome-wide transcriptomic analysis of adult mosquito hemocytes reveals pathogen-specific signatures of gene regulation and identifies several novel candidate genes for future functional studies. In order to identify hemocyte-specific and immune-responsive transcripts, we first compared transcripts expressed in hemocytes from one day old sugar-fed mosquitoes to transcripts detected in whole mosquitoes of the same age and feeding status. This resulted in identification of the hemocyte-enriched transcriptome. We then compared hemocytes from 1 day old mosquitoes, 1 hour after immune challenge with heat-killed Escherichia coli or Micrococcus luteus, to control female mosquitoes injected with sterile PBS to determine the bacteria challenge responsive transcriptomes. We used heat-killed bacteria in these assays, because our primary interest was in identifying the bacterial responsive transcriptome and to avoid the potentially confounding effects of altered gene expression due to the lethal effects of a systemic infection associated with injection of living bacteria. Lastly, we compared hemocytes from mosquitoes at 24 hours and 19 days after ingestion of a blood meal infected with Plasmodium berghei to mosquitoes of the same age fed a non-infected blood meal to determine the ookinete and sporozoite infection responsive transcriptomes, respectively. This design resulted in a total of five experimental treatments. The following samples are not included in this submission: Hemo E coli vs. hemo unchallenged A Hemo E coli vs. hemo unchallenged B Hemo m luteus vs. hemo unchallenged A Hemo m luteus vs. hemo unchallenged B
2011-10-31 | E-GEOD-33269 | biostudies-arrayexpress
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2010-05-27 | E-GEOD-9862 | biostudies-arrayexpress
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2010-05-27 | E-GEOD-2069 | biostudies-arrayexpress
Project description:Fetal lung development is a complex biological process, which involves temporal and spatial regulations of many genes. To understand molecular mechanisms of this process, we investigated gene expression profiling of lungs at gestational day 18, 19, 20, 21, new born, and adult rats using in-house rat DNA microarray containing 6,000 known genes and 4,000 ESTs. 1,512 genes passed SAM test and 583 genes (402 known genes and 181 ESTs) had a 2-fold change at least at one time point. K-means cluster analysis revealed 7 major expression patterns. Furthermore, using GeneMapp, we identified 3 regulatory pathways: TGF beta signaling pathway, cell cycle, and G-protein signaling; and 2 metabolism pathways: proteasome degradation and glycolysis. Our results suggest a complex regulatory pathway for fetal lung development. Loop Design as following: D18-D19-D20-D21-NB-AD-D18
2010-07-01 | E-GEOD-3302 | biostudies-arrayexpress
Project description:We have designed a zebrafish genomic microarray to identify DNA-protein interactions in the proximal promoter regions of over 11,000 zebrafish genes. Using these microarrays, together with chromatin immunoprecipitation with an antibody directed against tri-methylated lysine 4 of Histone H3, we demonstrate the feasibility of this method in zebrafish. This approach will allow investigators to determine the genomic binding locations of DNA interacting proteins during development and expedite the assembly of the genetic networks that regulate embryogenesis. Genomic array design Microarrays were designed as described below and manufactured by Agilent Technologies (www.agilent.com). Further information on design can be found at http://jura.wi.mit.edu/bioc/gbell/zfish_chip/. Selection of transcription start sites and identification of promoter sequences We interrogated 5 databases: Ensembl, VEGA, Refseq, ZGC full length clones and a database provided by Dr. Leonard Zon (Harvard Medical School, Boston, USA) in order to assemble an extensive list of zebrafish transcripts. The Zon lab database is a hand-curated database of zebrafish genes that have homologues in other species. We included all transcripts that appeared in the manually annotated databases (VEGA, Zon) and in the ZGC full length database. We also identified genes present in any 2 of the 5 databases and included those not already selected. The transcripts were mapped to the zebrafish genome (Zv4, June 2004) obtained from UCSC Bioinformatics (http://genome.ucsc.edu) and the transcription start site (TSS) for each transcript was determined. Transcripts with TSSs within 500bp were clustered into a transcriptional unit (TU) and promoter regions were identified relative to the most upstream TSS. This resulted in the identification of 13,413 TUs and corresponding promoter regions. Each promoter region was extracted and masked for repetitive sequence by RepeatMasker. If the promoter region contained a gap the upstream sequence was also masked. Information on the transcriptional units that were included in the final design can be found at http://jura.wi.mit.edu/bioc/gbell/zfish_chip/. Selection of oligonucleotides 60-mer oligonucleotide probes representing the region between 1.5kb upstream and 0.5kb downstream of the annotated TSS of each transcriptional unit were then designed. Although transcription factors and other DNA binding proteins are known to regulate genes from distances of greater than -1.5kb or + 0.5kb, much information can be gained from regions close to the TSS [45], and the H3K4Me3 mark studied in this paper is found at the most 5â end of a gene, close to the TSS. Selection of 60-mers for the microarrays was essentially as described in [14] using the Zv4 build of the zebrafish genome and a locally customized version of ArrayOligoSelector. 60-mers were chosen so that promoter regions contained approximately one probe every 250bp with a maximum distance between probes for each promoter region set at 600bp. In cases where only one probe could be designed for a particular TU these were not included in the final design. This process yielded 80,839 probes for 11,171 promoter regions We also incorporated several sets of control probes, both positive and negative. On each array there are 1090 probes designed against âgene desertâ regions, which are genomic regions that are unlikely to be bound by transcriptional regulators, and 270 probes designed against Arabidopsis thaliana genes, which are not present in the zebrafish genome (by BLAST). In addition, because our main motivation for making these microarrays is to identify mesodermally-regulated genes we included 7 genes expressed in mesoderm during gastrulation as positive controls (wnt11, flh, vent, msgn1, myod, fgf8, pcdh8). Probes designed against these promoters, which flank from 3-4kb around each TSS, are arrayed 2-4 times on each slide. Since these genes are expressed at gastrula stages to varying degrees, they also serve as a positive controls in this study. Finally there are 2256 controls added by Agilent and a variable number of blank spots. These probes were divided between two microarray slides each with 44,290 features. We refer to these two microarray slides as the âproximal promoter setâ. A proximal promoter set based on these designs as well as an expanded set of 9 slides which contain regions from â9kb to + 3kb relative to the TSS, are available by contacting Agilent (www.agilent.com) or by downloading the design files from http://jura.wi.mit.edu/bioc/gbell/zfish_chip/ for self-manufacture.
2010-07-01 | E-GEOD-4863 | biostudies-arrayexpress