Analysis of baseline gene expression in bone marrow derived dendritic cells (BMDC) from female CBA/J (CBA) and C57BL/6 (BL/6) mice. Results provide insight into strain-dependent differences in gene expression.
CD209a expression on dendritic cells is critical for the development of pathogenic Th17 cell responses in murine schistosomiasis.
Specimen part
View SamplesMessenger 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.
Chromatin measurements reveal contributions of synthesis and decay to steady-state mRNA levels.
Specimen part, Disease, Treatment, Time
View SamplesSingle cell sequencing of microglia and perivascular macrophages was performed on brain tissue from different brain regions to obtain single cell expression profiles dependent on celltype and regional location. Overall design: 425 cells from mouse (CD-1) brains at different postnatal ages as well as embryonic day E11.5-E18.5.
Spatial and temporal heterogeneity of mouse and human microglia at single-cell resolution.
Subject
View SamplesMicroglia play critical roles in neural development and homeostasis. They are also implicated in neurodegenerative and neuroinflammatory diseases of the central nervous system (CNS). However, little is known about the presence of spatially and temporally restricted subclasses of microglia during CNS development and disease. Here, we combined massively parallel single-cell analysis, single-molecule FISH, advanced immunohistochemistry and computational modelling to comprehensively characterize novel microglia subclasses, which were transcriptionally different from perivascular macrophages, in up to six different CNS regions during development and diseases. Single-cell analysis revealed specific time- and region-dependent microglia subtypes during homeostasis. In contrast, demyelinating and neurodegenerative diseases evoked context-dependent microglia subtypes with distinct molecular hallmarks and diverse cellular kinetics. Finally, diverse microglia subsets were also identified in normal and diseased human brains. Our data provide new insights into the CNS endogenous immune system during development, health and perturbations. Overall design: CD45+ cells isolated from healthy and MS-affected human brains were FACS-sorted in 384-well plates and used for scRNAseq. The patients were aged between 22 and 25 years. Data comprises 5 healthy and 5 MS patients. CEL-Seq2 protocol was used for single cell sequencing (Hashimshony et al. 2016).
Spatial and temporal heterogeneity of mouse and human microglia at single-cell resolution.
Specimen part, Subject
View SamplesThe 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.
Individual retinal progenitor cells display extensive heterogeneity of gene expression.
Specimen part
View SamplesRetinitis 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.
Gene expression changes within Müller glial cells in retinitis pigmentosa.
Specimen part
View SamplesRNAPII pausing/termination shortly after initiation is a hallmark of gene regulation. However, the molecular mechanisms involved are still to be uncovered. Here, we show that NELF interacts with Integrator complex subunits (INTScom) forming a stable complex with RNPII and Spt5. The interaction between NELF and INTScom subunits is RNA and DNA independent. Using both HIV-1 promoter and genome wide analyses, we demonstrate that Integrator subunits specifically control NELF-mediated RNAPII pause/release at coding genes. The strength of RNAPII pausing is determined by the nature of the NELF-associated complex. Interestingly, in addition to controlling RNAPII pause release INTS11 catalytic subunit of the INTScom is required for the synthesis of full length mRNA. Finally, INTScom-target genes are enriched in HIV-1 TAR/ NELF-binding element and in a 3'box sequence required for snRNA biogenesis. Revealing these unexpected functions of INTScom in regulating RNAPII pausing/release and completion of mRNA synthesis of NELF-target genes will contribute to our understanding of the gene expression cycle. Overall design: Genome-wide expression in HeLa cells in the absence of Integrator 11, or NELF or mock (control) depleted by strand-specific RNASeq (Illumina)
Integrator complex regulates NELF-mediated RNA polymerase II pause/release and processivity at coding genes.
No sample metadata fields
View SamplesThe 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.
Development and diversification of retinal amacrine interneurons at single cell resolution.
No sample metadata fields
View SamplesXRN2 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.
XRN2 Autoregulation and Control of Polycistronic Gene Expresssion in Caenorhabditis elegans.
Cell line, Subject
View SamplesRHAU (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.
Transcription-dependent nucleolar cap localization and possible nuclear function of DExH RNA helicase RHAU.
Sex
View Samples