Filters
Technology
Platform
SRP070060
Homo sapiens
2 Downloadable Samples
IlluminaHiSeq2000
Description
Mitochondrial DNA (mtDNA) mutations cause inherited diseases and are implicated in the pathogenesis of common late-onset disorders, but it is not clear how they arise and propagate in the humans. Here we show that mtDNA mutations are present in primordial germ cells (PGCs) within healthy female human embryos. Close scrutiny revealed the signature of selection against non-synonymous variants in the protein-coding region, tRNA gene variants, and variants in specific regions of the non-coding D-loop. In isolated single PGCs we saw a profound reduction in the cellular mtDNA content, with discrete mitochondria containing ~5 mtDNA molecules during early germline development. Single cell deep mtDNA sequencing showed rare variants reaching higher heteroplasmy levels in later PGCs, consistent with the observed genetic bottleneck, and predicting >80% levels within isolated organelles. Genome-wide RNA-seq showed a progressive upregulation of genes involving mtDNA replication and transcription, linked to a transition from glycolytic to oxidative metabolism. The metabolic shift exposes deleterious mutations to selection at the organellar level during early germ cell development. In this way, the genetic bottleneck prevents the relentless accumulation of mtDNA mutations in the human population predicted by Muller's ratchet. Mutations escaping this mechanism will, however, show massive shifts in heteroplasmy levels within one human generation, explaining the extreme phenotypic variation seen in human pedigrees with inherited mtDNA disorders. Overall design: RNA-Seq and NGS analysis to investigate transcriptomes and mtDNA sequences of fetal hPGCs
Publication Title
Segregation of mitochondrial DNA heteroplasmy through a developmental genetic bottleneck in human embryos.
Sample Metadata Fields
No sample metadata fields
View Samples- Mus musculus
- 16 Downloadable Samples
- Illumina HiSeq 2000
Description
Neural circuits in the medial entorhinal cortex (MEC) encode an animal’s position and orientation in space. Within the MEC spatial representations, including grid and directional firing fields, have a laminar and dorsoventral organization that corresponds to a similar topography of neuronal connectivity and cellular properties. Yet, in part due to the challenges of integrating anatomical data at the resolution of cortical layers and borders, we know little about the molecular components underlying this organization. To address this we develop a new computational pipeline for high-throughput analysis and comparison of in situ hybridization (ISH) images at laminar resolution. We apply this pipeline to ISH data for over 16,000 genes in the Allen Brain Atlas and validate our analysis with RNA sequencing of MEC tissue from adult mice. We find that differential gene expression delineates the borders of the MEC with neighboring brain structures and reveals its laminar and dorsoventral organization. Our analysis identifies ion channel-, cell adhesion- and synapse-related genes as candidates for functional differentiation of MEC layers and for encoding of spatial information at different scales along the dorsoventral axis of the MEC. Our results support the hypothesis that differences in gene expression contribute to functional specialization of superficial layers of the MEC and dorsoventral organization of the scale of spatial representations. Overall design: Examination of dorsal and ventral regions from 4 replicate samples each containing pooled data from 3-4 mice
Publication Title
Laminar and dorsoventral molecular organization of the medial entorhinal cortex revealed by large-scale anatomical analysis of gene expression.
Sample Metadata Fields
No sample metadata fields
View Samples- Mus musculus
- 18 Downloadable Samples
Affymetrix Mouse Gene 1.0 ST Array (mogene10st)
Description
DNA microarray analysis was performed with mouse multipotent adult germline stem cells (maGSCs) and embryonic stem cells (ESCs) from different genetic backgrounds cultured under standard ESC culture conditions and under differentiation-promoting conditions by the withdrawal of Leukemia Inhibitory Factor (LIF) and treatment with Retinoic Acid (RA). The analyzed undifferentiated cell lines are very similar based on their global gene expression pattern and show 97-99% identity dependent on the analyzed background. Only 621 genes are differentially expressed in cells derived from mouse 129SV-background, and 72 genes show differences in expression in cells generated from transgenic Stra8-EGFP/Rosa26-LacZ-background. Both maGSCs and ESCs express the same genes involved in the regulation of pluripotency, and even show no differences in the expression level of these genes. When comparing maGSCs with previously published signature genes of other pluripotent cell lines we could find that maGSCs share a very similar gene expression pattern with embryonic germ cells (EGCs). Also after differentiation of maGSCs and ESCs the transcriptomes of the cell lines are nearly identical which suggests that both cell types differentiate spontaneously in a very similar way. This is the first study comparing ESCs and a pluripotent cell line derived from an adult organism (maGSCs) on transcriptome level.
Publication Title
Pluripotent embryonic stem cells and multipotent adult germline stem cells reveal similar transcriptomes including pluripotency-related genes.
Sample Metadata Fields
Specimen part
View Samples- Gallus gallus
- 3 Downloadable Samples
- Illumina Genome Analyzer IIx
Description
Avian pathogenic Escherichia coli (APEC) is considered one of the most common infectious bacterial diseases resulting in significant economic losses in poultry industry worldwide. In order to investigate the association between host immune resistance and miRNA expression in the pathogenic process induced by APEC, miRNA expression profiles in broilers spleen were performed by Solexa deep sequencing from three different treatment groups including non-challenged (NC), challenged-mild pathology (MD), and challenged-severe pathology (SV).In total, 3 462 706, 3 586 689, and 3 591 027 clean reads were obtained for NC, MD, and SV, respectively. After comparing the miRNA expression patterns, 27 differentially expressed miRNAs were identified among the three response groups, which included 13 miRNAs between NC and MD, 17 between NC and SV, and 14 between MD and SV. For these miRNAs, different expression in MD and SV suggested they may have resistance activity in APEC infection. Through integrated analysis of miRNA and mRNA expression patterns, 43 negative pairs between miRNA and mRNA (r < -0.80) were obtained. 4 miRNAs were validated to be significant negatively correlated to targets by quantitative real time PCR: gga-miR-21 (CLEC3B and GGTLA1), gga-miR-429 (TMEFF2, CDC20, SHISA2 and NOX4), gga-miR-146b (LAT2 and WNK1), and gga-miR-215 (C7 and ASL2). Additionally, the expression of gga-miR-21 and gga-miR-146b was significantly up-regulated by LPS induced in HD11 macrophage cell. In contrast, gga-miR-429 has no significant change. In summary, we present the first report that characterized the miRNA profiles of chicken spleen in response to APEC infection, and identified several candidate miRNAs which might accelerate host immune response through down-regulating their specific target genes. Overall design: Through the intra-air sac route into the left thoracic air sac, 240 non-vaccinated males at 4 weeks of age were challenged with 0.1 ml APEC O1 (10^8 colony forming units) and another 120 non-vaccinated males were non-challenged but treated with 0.1 ml PBS. Detailed information on the APEC O1 strain and challenge process was described by previously described study. Necropsy was performed at 1 day post challenge, and a summarized lesion ranging from 0 to 7 was determined for each APEC-challenged bird. Birds with lesions scoring 0-2 were regarded as mild infection, and those scoring 4-7 were designated as severe infection. The mild and severe pathology meant that birds were resistant and susceptible to APEC infection, respectively. Then, spleens from three groups, consisting of non-challenged, challenged-mild pathology and challenged-severe pathology were subjected to Solexa deep sequencing to investigate the dynamics of chicken miRNA expression.
Publication Title
Novel MicroRNA Involved in Host Response to Avian Pathogenic Escherichia coli Identified by Deep Sequencing and Integration Analysis.
Sample Metadata Fields
Sex, Age, Specimen part, Subject
View Samples- Anopheles gambiae
- 60 Downloadable Samples
- Affymetrix Plasmodium/Anopheles Genome Array (plasmodiumanopheles)
Description
Background.
Publication Title
A comprehensive gene expression atlas of sex- and tissue-specificity in the malaria vector, Anopheles gambiae.
Sample Metadata Fields
Sex, Specimen part
View Samples- Homo sapiens
- 9 Downloadable Samples
- Illumina HiSeq 2000
Description
We describe the preparation, evaluation, and application of an S100A12 protein-conjugated solid support, hereafter the “A12-resin,” that can remove 99% of Zn(II) from complex biological solutions without significantly perturbing the concentrations of other metal ions. The A12-resin can be applied to selectively deplete Zn(II) from diverse tissue culture media and from other biological fluids including human sera. To further demonstrate the utility of this approach, we investigated metabolic, transcriptomic, and metallomic responses of HEK293T cells cultured in medium depleted of Zn(II) using S100A12. Our data indicate that dividing cells can maintain a constant pool of free Zn(II), even under conditions of severe Zn(II) deprivation. We expect that the A12-resin will facilitate interrogation of disrupted Zn(II) homeostasis in biological settings, uncovering novel roles for Zn(II) in biology. Overall design: Defining the response of a cell line to Zn(II) starvation
Publication Title
A Method for Selective Depletion of Zn(II) Ions from Complex Biological Media and Evaluation of Cellular Consequences of Zn(II) Deficiency.
Sample Metadata Fields
Cell line, Subject
View Samples- Arabidopsis thaliana
- 53 Downloadable Samples
- Illumina HiSeq 2000
Description
We report global gene expression profilies of Brassinosteroid related Arabidopsis mutants in response to dehydration and fixed-carbon starvation stresses by RNA-seq Overall design: Arabidopsis plants of listed genotypes were grown for 4 weeks under long day (16 hour light) conditions before being subjected to control, 4 hour dehydration, or 5 day fixed carbon starvation treatments.
Publication Title
Arabidopsis WRKY46, WRKY54, and WRKY70 Transcription Factors Are Involved in Brassinosteroid-Regulated Plant Growth and Drought Responses.
Sample Metadata Fields
Specimen part, Treatment, Subject
View Samples- Drosophila melanogaster
- 9 Downloadable Samples
- Affymetrix Drosophila Genome 2.0 Array (drosophila2)
Description
Cardiogenesis involves multiple biological processes acting in concert during development, a coordination achieved by the regulation of diverse cardiac genes by a finite set of transcription factors (TFs). Previous work from our laboratory identified the roles of two Forkhead TFs, Checkpoint suppressor homologue (CHES-1-like) and Jumeau (Jumu) in governing cardiac progenitor cell divisions by regulating Polo kinase activity. These TFs were also implicated in the regulation of numerous other cardiac genes. Here we show that these two Forkhead TFs play an additional and mutually redundant role in specifying the cardiac mesoderm (CM): eliminating the functions of both CHES-1-like and jumu in the same embryo results in defective hearts with missing hemisegments. Our observations indicate that this process is mediated by the Forkhead TFs regulating the fibroblast growth factor receptor Heartless (Htl) and the Wnt receptor Frizzled (Fz), both previously known to function in cardiac progenitor specification: CHES-1-like and jumu exhibit synergistic genetic interactions with htl and fz in CM specification, thereby implying function through the same genetic pathways, and transcriptionally activate the expression of both receptor-encoding genes. Furthermore, ectopic overexpression of either htl or fz in the mesoderm partially rescues the defective CM specification phenotype seen in embryos doubly homozygous for mutations in jumu and CHES-1-like. Together, these data emphasize the functional redundancy that leads to robustness in the cardiac progenitor specification process mediated by Forkhead TFs regulating the expression of signaling pathway receptors, and illustrate the pleiotropic functions of this class of TFs in different aspects of cardiogenesis.
Publication Title
Two forkhead transcription factors regulate the division of cardiac progenitor cells by a Polo-dependent pathway.
Sample Metadata Fields
Specimen part
View Samples- Drosophila melanogaster
- 5 Downloadable Samples
- Affymetrix Drosophila Genome Array (drosgenome1)
Description
The development of a complex organ requires the specification of appropriate numbers of each of its constituent cell types, as well as their proper differentiation and correct positioning relative to each other. During Drosophila cardiogenesis, all three of these processes are controlled by jumeau (jumu) and Checkpoint suppressor homologue (CHES-1-like), two genes encoding forkhead transcription factors that we discovered utilizing an integrated genetic, genomic and computational strategy for identifying novel genes expressed in the developing Drosophila heart. Both jumu and CHES-1-like are required during asymmetric cell division for the derivation of two distinct cardiac cell types from their mutual precursor, and in symmetric cell divisions that produce yet a third type of heart cell. jumu and CHES-1-like control the division of cardiac progenitors by regulating the activity of Polo, a kinase involved in multiple steps of mitosis. This pathway demonstrates how transcription factors integrate diverse developmental processes during organogenesis.
Publication Title
Two forkhead transcription factors regulate the division of cardiac progenitor cells by a Polo-dependent pathway.
Sample Metadata Fields
Specimen part
View Samples- Drosophila melanogaster
- 6 Downloadable Samples
- Affymetrix Drosophila Genome 2.0 Array (drosophila2)
Description
The development of a complex organ requires the specification of appropriate numbers of each of its constituent cell types, as well as their proper differentiation and correct positioning relative to each other. During Drosophila cardiogenesis, all three of these processes are controlled by jumeau (jumu) and Checkpoint suppressor homologue (CHES-1-like), two genes encoding forkhead transcription factors that we discovered utilizing an integrated genetic, genomic and computational strategy for identifying novel genes expressed in the developing Drosophila heart. Both jumu and CHES-1-like are required during asymmetric cell division for the derivation of two distinct cardiac cell types from their mutual precursor, and in symmetric cell divisions that produce yet a third type of heart cell. jumu and CHES-1-like control the division of cardiac progenitors by regulating the activity of Polo, a kinase involved in multiple steps of mitosis. This pathway demonstrates how transcription factors integrate diverse developmental processes during organogenesis.
Publication Title
Two forkhead transcription factors regulate the division of cardiac progenitor cells by a Polo-dependent pathway.
Sample Metadata Fields
Specimen part
View Samples