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GSE33252
Mus musculus
19 Downloadable Samples
Affymetrix Mouse Gene 1.0 ST Array (mogene10st)
Description
Messenger RNA levels in eukaryotes are balanced by two consecutive regulatory layers. Primary, transcriptional regulation at the level of chromatin and secondary, post-transcriptional regulation of the initial transcript in the cytoplasm. Each layer is individually studied in mechanistic detail, while integration of both processes is required to quantify the individual contribution to steady-state RNA levels. Here we show that chromatin features are sufficient to model transcription rate but with different sensitivities in dividing versus post mitotic cells. In both cases chromatin derived transcript levels explains over 80% of variance in measured RNA level enabling to separate transcription from different post-transcriptional processes. By further inclusion of measurements of mRNA half-life and micro RNA expression data we identify a low quantitative contribution of RNA decay by either micro RNA or general differential turnover to final mRNA levels. Together this establishes a chromatin based quantitative model for the contribution of transcriptional and posttranscriptional processes to steady-state levels of messenger RNA.
Publication Title
Chromatin measurements reveal contributions of synthesis and decay to steady-state mRNA levels.
Sample Metadata Fields
Specimen part, Disease, Treatment, Time
View Samples- Mus musculus
- 41 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
The development of complex tissues requires that mitotic progenitor cells integrate information from the environment. The highly varied outcomes of such integration processes undoubtedly depend at least in part upon variations among the gene expression programs of individual progenitor cells. To date, there has not been a comprehensive examination of these differences among progenitor cells of a particular tissue. Here, we used comprehensive gene expression profiling to define these differences among individual progenitor cells of the vertebrate retina. Retinal progenitor cells (RPCs) have been shown by lineage analysis to be multipotent throughout development and to produce distinct types of daughter cells in a temporal, conserved order. A total of 42 single RPCs were profiled on Affymetrix arrays. An extensive amount of heterogeneity in gene expression among RPCs, even among cells isolated from the same developmental time point, was observed. While many classes of genes displayed heterogeneity of gene expression, the expression of transcription factors constituted a significant amount of the observed heterogeneity. Additionally, the expression of cell cycle related transcripts showed differences among those associated with G2 and M, versus G1 and S phase, suggesting different levels of regulation for these genes. These data provide insights into the types of processes and genes that are fundamental to cell fate choices, proliferation decisions, and, for cells of the central nervous system, the underpinnings of the formation of complex circuitry.
Publication Title
Individual retinal progenitor cells display extensive heterogeneity of gene expression.
Sample Metadata Fields
Specimen part
View Samples- Mus musculus
- 28 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
Retinitis Pigmentosa (RP) is a progressive retinal degeneration in which the retina loses nearly all of its photoreceptor cells and undergoes major structural changes. Little is known regarding the role the resident glia, the Mller glia, play in the progression of the disease. Here we define gene expression changes in Mller glial cells (MGCs) from two different mouse models of RP, the retinal degeneration 1 (rd1) and rhodopsin knock-out (Rhod-ko) models. The RNA repertoire of 28 single MGCs was comprehensively profiled, and a comparison was made between MGC from wild type (WT) and mutant retinas. Two time points were chosen for analysis, one at the peak of rod photoreceptor death and one during the period of cone photoreceptor death. MGCs have been shown to respond to retinal degeneration by undergoing gliosis, a process marked by the upregulation of GFAP. In this data, many additional transcripts were found to change. These can be placed into functional clusters, such as retinal remodeling, stress response, and immune related response. It is noteworthy that a high degree of heterogeneity among the individual cells was observed, possibly due to their different spatial proximities to dying cells, and/or inherent heterogeneity among MGCs.
Publication Title
Gene expression changes within Müller glial cells in retinitis pigmentosa.
Sample Metadata Fields
Specimen part
View Samples- Mus musculus
- 25 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
The vertebrate retina uses diverse neuronal cell types arrayed into complex neural circuits to extract, process and relay information from the visual scene to the higher order processing centers of the brain. Amacrine cells, a diverse class of inhibitory interneurons, are thought to mediate the majority of the processing of the visual signal that occurs within the retina. Despite morphological characterization, the number of known molecular markers of amacrine cell types is still much smaller than the 26 morphological types that have been identified. Furthermore, it is not known how this diversity arises during development. Here, we have combined in vivo genetic labeling and single cell genome-wide expression profiling to: 1) Identify specific molecular types of amacrine cells; 2) Demonstrate the molecular diversity of the amacrine cell class.
Publication Title
Development and diversification of retinal amacrine interneurons at single cell resolution.
Sample Metadata Fields
No sample metadata fields
View Samples- Caenorhabditis elegans
- 8 Downloadable Samples
Illumina HiSeq 2500
Description
XRN2 is a conserved 5’-->3’ exoribonuclease that complexes with XTB-domain containing proteins. Thus, in Caenorhabditis elegans (C. elegans), the XTBD-protein PAXT-1 stabilizes XRN2 to retain its activity. XRN2 activity is also promoted by 3''(2''),5''-bisphosphate nucleotidase 1 (BPNT1) through its hydrolysis of 3’-phosphoadenosine-5''-bisphosphate (PAP), an endogenous XRN inhibitor. Here, we find through unbiased screening that loss of bpnt-1 function suppresses lethality caused by paxt-1 deletion. This unexpected finding is explained by XRN2 autoregulation, which occurs through repression of a cryptic promoter activity and destabilization of the xrn-2 transcript. Autoregulation appears to be triggered at different thresholds of XRN2 inactivation, such that more robust XRN2 perturbation, by elimination of both PAXT-1 and BPNT1, is less detrimental to worm viability than absence of PAXT-1 alone. Like more than 15% of C. elegans genes, xrn-2 occurs in an operon, and we identify additional operons under its control, consistent with a broader function of XRN2 in polycistronic gene regulation. Regulation occurs through intercistronic regions that link genes in an operon, but similar mechanisms may allow XRN2 to operate on monocistronic genes in organisms lacking operons. Overall design: Wild-type C. elegans worms were subjected to mock or xrn-2 RNAi from L1 to L4 stage at 20°C. Total RNA was extracted from the worms, and polyadenylated RNA was analyzed.
Publication Title
XRN2 Autoregulation and Control of Polycistronic Gene Expresssion in Caenorhabditis elegans.
Sample Metadata Fields
Cell line, Subject
View Samples- Homo sapiens
- 52 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
RHAU (RNA helicase-associated with AU-rich element) is a DExH protein that was originally identified as a factor accelerating AU-rich element-mediated mRNA degradation. The finding that RHAU is predominantly localized in the nucleus, despite that mRNA degradation occurs in cytoplasm, prompted us to consider nuclear functions of RHAU. In HeLa cells, RHAU was localized throughout the nucleoplasm with some concentration in nuclear speckles in a manner dependent on ATPase activity. Transcriptional arrest altered its localization to nucleolar caps where it was colocalized with other RNA helicases, p68 and p72, suggesting that RHAU is involved in transcription-related RNA metabolism in the nucleus. To see whether RHAU affects global gene expression either transcriptionally or posttranscriptionally, we performed microarray analysis using total RNA prepared from RHAU-depleted HeLa cell lines, measuring both steady-state mRNA levels and mRNA half-lives by ActinomycinD-chase. We found that most transcripts whose steady-state levels were affected by RHAU knockdown did not show changes in their half-lives, suggesting the involvement of transcriptional regulation for these transcripts. We propose that RHAU has dual functions involved in synthesis and degradation of mRNA in different subcellular compartments.
Publication Title
Transcription-dependent nucleolar cap localization and possible nuclear function of DExH RNA helicase RHAU.
Sample Metadata Fields
Sex
View Samples- Drosophila melanogaster
- 10 Downloadable Samples
- Affymetrix Drosophila Genome 2.0 Array (drosophila2)
Description
The replication of a genomic region during S-phase can be highly dynamic between cell types that differ in transcriptome and epigenome. Replication timing has been positively correlated with several histone modifications that occur at active genes, while repressive histone modifications mark late replicating regions. This raises the question if chromatin modulates the initiating events of replication. To gain insights into this question we have studied the function of heterochromatin protein 1 (HP1), a reader of to the repressive histone lysine 9 methylation of H3, in genome-wide organization of replication. Cells with reduced levels of HP1 show an advanced replication timing of centromeric repeats in agreement with the model that repressive chromatin mediates the very late replication of large clusters of constitutive heterochromatin. Surprisingly however regions with high levels of interspersed repeats on the chromosomal arms in particular on chromosome 4 and in pericentromeric regions of chromosome 2 behave differently. Here loss of HP1 results in delayed replication timing. The fact that these regions are bound by HP1 suggests a direct effect. Thus while HP1 mediates very late replication of centromeric DNA it is also required for early replication of autosomal regions with high levels of repeats. This observation of opposing functions of HP1 suggests a model where repeat inactivation on autosomes is required for proper activation of origins of replication that fire early, while HP1 mediated repression at constitutive heterochromatin is required to ensure replication of centromeric repeats at the end of S phase.
Publication Title
Heterochromatin protein 1 (HP1) modulates replication timing of the Drosophila genome.
Sample Metadata Fields
Sex, Specimen part
View Samples- Mus musculus
- 12 Downloadable Samples
- Affymetrix Mouse Expression 430A Array (moe430a)
Description
Transcriptomes of mouse embryonic autopods were generated detecting expression of approximately 26179 transcripts in the developing forelimb or hindlimb autopods, representing about 58 % of the probe sets on MOE-430 A/B GeneChip. Three biological replicate array experiments were finished for each condition and MAS5.0 signal were used to do data analysis. Forty-four transcripts with expression differences higher than 2-fold were detected(T test, P<0.05), including Tbx4, Tbx5, Hoxc10 and Pitx1 which were previously shown to be differentially expressed in developing forelimb and hindlimb bud by in situ hybridization and SAGE study (Margulies 2001). RTPCR and in situ experiments confirmed several top differentially expressed genes which were newly discovered by our experiments. Vast amount of transcripts and its family members such as Bmp, Fgf, Epha, Wnt, T-box and Hox families detected to be highly expressed or differentially expressed in developing autopods, suggesting that the complexity of transcriptomes of developing autopods and dynamic differential expression and differential combinations of gene expression signals in the developing limb tissue contributes to differences in forelimb versus hindlimb patterning. The differentially expressed genes are the essential factors for morphological diversification of developing limb structures.
Publication Title
Transcriptome analysis of the murine forelimb and hindlimb autopod.
Sample Metadata Fields
No sample metadata fields
View Samples- Caenorhabditis elegans
- 10 Downloadable Samples
- Illumina HiSeq 2000
Description
microRNAs (miRNAs) constitute a class of small non-coding RNAs (~22nt). They are thought to be generally stable with half-lives of many hours or even days. However, several miRNAs have been reported to decay rapidly in specific situations. In order to examine miRNA stability on a global scale, we quantify relative decay rates of miRNA in first larval stage C. elegans worms that are treated with a transcription inhibitor alpha-amanitin by deep sequencing. Several miRNAs including members of the miR-35 and miR-51 families exhibit accelerated decay. Moreover, biogenesis of miRNAs involves generation of a miRNA duplex intermediate consisting of the miRNA guide strand (miR) and the miRNA passenger strand (miR*). miR and miR* names were originally assigned based on the relative abundance of each strand, with the less abundant strand presumed to be inactive, and thus the miR*. However, subsequent research showed that at least individual miR*s can have biological activity. Our sequencing data reveal that miR*s, operationally defined on the basis of their relative abundance at time point t=1h, are substantially less stable than miRs. This would appear to support the notion that miR*s mainly constitute processing byproducts rather than a less abundant class of functional miRNAs. Overall design: Examination of microRNA decay rates in the first larval stage C. elegans worms.
Publication Title
Engineering of a conditional allele reveals multiple roles of XRN2 in Caenorhabditis elegans development and substrate specificity in microRNA turnover.
Sample Metadata Fields
Specimen part, Cell line, Treatment, Subject
View Samples- Mus musculus
- 10 Downloadable Samples
- Affymetrix Mouse Gene 1.0 ST Array (mogene10st)
Description
This SuperSeries is composed of the SubSeries listed below.
Publication Title
A chromatin-modifying function of JNK during stem cell differentiation.
Sample Metadata Fields
Specimen part, Treatment
View Samples