Background: Among full autosomal trisomies, only trisomies of chromosome 21 (Down syndrome, DS), 18 (Edward syndrome, ES) and 13 (Patau syndrome, PS) are compatible with postnatal survival. But the mechanisms, how a supernumerary chromosome disrupts the normal development and causes specific phenotypes, are still not fully explained. As an alternative to gene dosage effects due to the trisomic chromosome, a genome-wide transcriptional dysregulation has been postulated. The aim of this study was to define the transcriptional changes in trisomy 13, 18, and 21 during early fetal development in order to define whether (1) overexpression of genes of the trisomic chromosome contributes solely to the phenotype, if (2) all genes of the trisomic chromosome are upregulated similarly and whether the ratio of gene expression is in agreement with the gene dosis, (3) whether the different trisomies behave similarly in the characteristics of transcriptional dysregulation, and (4) whether transcriptional pattern can be potentially used in prenatal diagnosis. Methods: Using oligonucleotide microarrays (Affymetrix, U133 Plus 2.0), we analyzed whole genome expression profiles representing 54.000 probe sets in cultured amniocytes (AC) and chorion villus cells (CV) from pregnancies with a normal karyotype and with trisomies of human chromosomes 21, 18 and 13. Findings: We observed a low to moderate up-regulation for a subset of genes of the trisomic chromosomes. Transcriptional level of approximately 12-13 % of the supernumerary chromosome appeared similar to the respective chromosome pair in normal karyotypes. Expression values as well as the expression patterns of genes from the trisomic chromosome can distinguish the respective trisomic samples from euploid controls. A subset of chromosome 21-genes including the DSCR1-gene involved in fetal heart development was consistently up-regulated in different tissues (AC, CV) of trisomy 21 fetuses whereas only minor changes were found for genes of all other chromosomes. In contrast, in trisomy 13 and trisomy 18 vigorous downstream transcriptional changes were found. Interpretation: Global transcriptome analysis for autosomal trisomies 13, 18, and 21 supported a combination of the two major hypotheses. As several transcriptional pathways are altered, complex regulatory mechanisms are involved in the pathogenesis of autosomal trisomies. A genome-wide transcriptional dysregulation was predominantly observed in trisomies 13 and 18, whereas a more to chromosome 21 restricted expression alteration was found in trisomy 21.
Specific transcriptional changes in human fetuses with autosomal trisomies.
Sex, Age, Specimen part
View SamplesAnopheles gambiae,the primary African malarial mosquito, exhibits numerous behaviors that are under diel and circadian control, including locomotor activity, swarming, mating, host seeking, eclosion, egg laying and sugar feeding. However, little has been performed to elucidate the molecular basis for these daily rhythms. To study how gene expression is globally regulated by diel and circadian mechanisms, we have undertaken a DNA microarray analysis ofA. gambiaehead and bodies under 12:12 light:dark cycle (LD) and constant dark (DD, free-running) conditions. Zeitgeber Time (ZT) with ZT12 defined as time of lights OFF under the light:dark cycle, and ZT0 defined as end of the dawn transition. Circadian Time (CT) with CT0 defined as subjective dawn, inferred from ZT0 of the previous light:dark cycle.
Genome-wide profiling of diel and circadian gene expression in the malaria vector Anopheles gambiae.
Sex, Specimen part
View SamplesChronic inflammation during placental malaria (PM) caused by Plasmodium falciparum is most frequent in first-time mothers and is associated with poor maternal and fetal outcomes. In the first genome wide analysis of the local human response to sequestered malaria parasites, we identified genes associated with chronic PM, then localized the corresponding proteins and immune cell subsets in placental cryosections.
Genome-wide expression analysis of placental malaria reveals features of lymphoid neogenesis during chronic infection.
No sample metadata fields
View SamplesWe have used deep sequencing to explore the repertoire of both poly(A)+ and poly(A)- RNAs from two standard cell lines, HeLa cells and human embryonic stem cell (hESC) H9 cells. Overall design: Examination of nonpolyadenylated and polyadenylated in 2 cell types.
Genomewide characterization of non-polyadenylated RNAs.
Cell line, Subject
View SamplesEstrogen-related receptor (ERR) alpha is an orphan nuclear receptor highly expressed in the kidneys. ERRalpha is implicated in renal sodium and potassium homeostasis and blood pressure regulation. We used microarray analysis to identify differentially expressed genes in ERR alpha knockout mice kidneys versus wild-type. The results provide insight on the roles of ERRalpha in the kidney.
Physiological genomics identifies estrogen-related receptor alpha as a regulator of renal sodium and potassium homeostasis and the renin-angiotensin pathway.
Sex, Specimen part
View SamplesWe have used deep sequencing to explore the repertoire of both poly(A)+ and poly(A)- RNAs from two standard cell lines, HeLa cells and human embryonic stem cell (hESC) H9 cells. Overall design: Examination of nonpolyadenylated and polyadenylated RNA in 2 cell types.
Genomewide characterization of non-polyadenylated RNAs.
No sample metadata fields
View SamplesPurpose: we tested the hypothesis that Hltf deletion in placenta either caused or exacerbated neonatal hypoglycemia via Hif-1a regulation of nutrient transporters. Methods: Individual samples [1 term placenta/sample x 5 biological replicates for test and control littermate female mice = 10 total samples] were flash frozen and sent to Otogenetics Corp. (Norcross, GA) for RNA-seq assays. Paired-end 100 nucleotide reads were aligned to genomic assembly mm10 and analyzed using the platform provided by DNAnexus, Inc. (Mountain View, CA). Results: There was no measureable evidence of uteroplacental dysfunction or fetal compromise. Conclusion: Our study is the first to show only the truncated Hltf isoform is expressed in E18.5 term placenta, and we identified a functional link between alternative splicing of Hltf and immunosuppression at the feto-maternal interface. Overall design: Placental mRNA profiles of E18.5 term placenta from five wild type control and five Hltf null mouse samples were generated by deep sequencing by Illumina HiSeq2000/2500.
Alternative splicing of helicase-like transcription factor (Hltf): Intron retention-dependent activation of immune tolerance at the feto-maternal interface.
Specimen part, Cell line, Subject
View SamplesWe describe a chemical method to label and purify 4-thiouridine (s4U) -containing RNA. We demonstrate that methanethiolsulfonate (MTS) reagents form disulfide bonds with s4U more efficiently than the commonly used HPDP-biotin, leading to higher yields and less biased enrichment. This increase in efficiency allowed us to use s4U-labeling to study global microRNA (miRNA) turnover in proliferating cultured human cells without perturbing global miRNA levels or the miRNA processing machinery. This improved chemistry will enhance methods that depend on tracking different populations of RNA such as 4-thiouridine-tagging to study tissue-specific transcription and dynamic transcriptome analysis (DTA) to study RNA turnover. Overall design: s4U metabolic labeling of RNA in 293T cells, followed by biochemical enrichment of labeled RNA with two biotinylation reagents, RNAs >200nt and miRNAs in separate experiments
Tracking Distinct RNA Populations Using Efficient and Reversible Covalent Chemistry.
No sample metadata fields
View SamplesNo description.
Conservation of an RNA regulatory map between Drosophila and mammals.
Cell line, Subject
View SamplesTotal RNA was isolated from 3 WT and 3 ERRa null hearts and independent hybridizations were performed using MOE430 2.0 microarrays. Expression profiling was conducted to determine changes in gene expression in hearts lacking ERRa. The expression of genes involved in heart and muscle development, muscle contraction, lipid metabolism, OxPhos, protein metabolism and transcription were affected by the loss of ERRa.
Genome-wide orchestration of cardiac functions by the orphan nuclear receptors ERRalpha and gamma.
Sex, Specimen part
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