The right ventricle (RV) differs in several aspects from the left ventricle (LV) including its embryonic origin, physiological role and anatomical design. In contrast to LV hypertrophy, little is known about the molecular circuits, which are activated upon RV hypertrophy (RVH). We established a highly reproducible model of RVH in mice using pulmonary artery clipping (PAC), which avoids detrimental RV pressure overload and thus allows long-term survival of operated mice. Magnetic resonance imaging revealed pathognomonic changes with striking similarities to human congenital heart disease- or pulmonary arterial hypertension- patients. Comparative, microarray based transcriptome analysis of right- and left-ventricular remodeling identified distinct transcriptional responses to pressure-induced hypertrophy of either ventricle, which were mainly characterized by stronger transcriptional responses of the RV compared to the LV myocardium. Hierarchic cluster analysis revealed a RV- and LV-specific pattern of gene activity after induction of hypertrophy, however, we did not find evidence for qualitatively distinct regulatory pathways in RV compared to LV. Data mining of nearly three thousand RV-enriched genes under PAC disclosed novel potential (co)-regulators of long-term RV remodeling and hypertrophy. We reason that specific inhibitory mechanisms in RV restrict excessive myocardial hypertrophy and thereby contribute to its vulnerability to pressure overload.
Identification of right heart-enriched genes in a murine model of chronic outflow tract obstruction.
Sex, Age, Specimen part
View SamplesLong non-coding RNAs (lncRNAs) contribute to (patho)physiological processes in the heart. Aging is the major risk factor for cardiovascular disease and cardiomyocyte apoptosis is an underlying cause for age-related cardiac dysfunction. RNA sequencing of cardiomyocytes from young and aged mouse hearts revealed several aging-regulated lncRNAs. An siRNA screen for caspase activity identified the aging-regulated lncRNA Sarrah (ENSMUST00000140003) as anti-apoptotic, which we confirmed in human cells (human SARRAH is annotated as OXCT1-AS1). Importantly, human engineered heart tissue showed impaired contractile force development upon SARRAH knockdown compared with controls. Computational prediction of RNA-DNA triple helix formation showed that SARRAH may directly bind the promoters of genes downregulated after SARRAH silencing, which mainly consist of cell survival genes. Indeed, nuclear magnetic resonance spectroscopy confirmed RNA-DNA triple helix formation and cardiomyocytes lacking the triple helix-forming domain of Sarrah showed an increase in apoptosis. One of the key direct SARRAH targets is NRF2, an anti-oxidant transcription factor. Restoration of NRF2 levels after SARRAH silencing partially rescues the reduction in cell viability. RNA affinity purification mass spectrometry analysis identified CRIP2 as main protein interaction partner. Furthermore, SARRAH associates with acetyltransferase p300 and acetylated histone H3K27. Finally, Sarrah was also profoundly downregulated after acute myocardial infarction (AMI) in mice. Adeno-associated virus-mediated overexpression of Sarrah in mice showed better recovery of cardiac contractile function after AMI compared to control mice, as measured by echocardiography and magnetic resonance imaging, consistent with a decrease in cardiomyocyte cell death and an increase in endothelial cell proliferation. In summary, we identified the anti-apoptotic evolutionary conserved lncRNA Sarrah, which is downregulated by aging, as a pivotal regulator of cardiomyocyte survival. Sarrah overexpression has beneficial effects on AMI recovery highlighting it as a potential therapeutic approach against heart failure.
Aging-regulated anti-apoptotic long non-coding RNA Sarrah augments recovery from acute myocardial infarction.
Specimen part
View SamplesWe have shown that activin promoted skin tumorigenesis in mice induced by the human papilloma virus 8 oncogenes. Activin attracted blood monocytes to the skin as revealed by depletion of CCR2-positive monocytes. To determine if activin also altered the gene expression profile of these cells, we performed RNA-Sequencing of macrophages FACS-sorted from the pre-cancerous ear skin. We have found that activin induces a pro-migratiory, pro-angiogenic and pro-tumorigenic genes in skin macrophages in vivo. This largely contributes to the pro-tumorigenic function of activin, since macrophage depletion delayed spontaneous tumorigenesis in HPV8-transgenic mice by reducing keratinocyte proliferation and angiogenesis. Overall design: F4/80+CD11b+CD45+ cells were FACS-sorted from the pre-cancerous ear skin of wt/wt, HPV8/wt, wt/Act and HPV8/Act mice and their expression profile was analysed by RNA-Sequencing. Experiment was performed in triplicates, for each replicate ear skin of 3-6 mice of corresponding genotype was pooled.
Activin promotes skin carcinogenesis by attraction and reprogramming of macrophages.
Specimen part, Cell line, Subject
View SamplesDuring HIV-1 infection, there is a massive perturbation of host gene expression, but as yet, genome-wide studies have not identified host genes affecting HIV-1 replication in lymphatic tissue, the primary site of virus-host interactions. In this study, we isolated RNA from the inguinal lymph nodes of 22 HIV-1-infected individuals and utilized a microarray approach to identify host genes critically important for viral replication in lymphatic tissue by examining gene expression associated with viral load. Strikingly, ~95% of the transcripts (558) in this data set (592 transcripts total) were negatively associated with HIV-1 replication. Genes in this subset (1) inhibit cellular activation/proliferation (ex.: TCFL5, SOCS5 and SCOS7, KLF10), (2) promote heterochromatin formation (ex.: HIC2, CREBZF, ZNF148/ZBP-89), (3) increase collagen synthesis (ex.: PLOD2, POSTN, CRTAP), and (4) reduce cellular transcription and translation. Potential anti-HIV-1 restriction factors were also identified (ex.: NR3C1, HNRNPU, PACT). Only ~5% of the transcripts (34) were positively associated with HIV-1 replication. Paradoxically, nearly all these genes function in innate and adaptive immunity, particularly highlighting a heightened interferon system. The predominance of negative correlations as well as the disconnect between host defenses and viral load point to the importance of genes that regulate target cell activation and genes that code for potentially new restriction factors as determinants of viral load rather than conventional host defenses.
Host genes associated with HIV-1 replication in lymphatic tissue.
Sex, Age, Specimen part, Race
View SamplesDifferentiating human dendritic cells were stimulated for 12 hours with RXR agonists (LG268, 9CRA, R- and S-9CDHRA) or agonists for RXR partners including GW3965 (LXR/ panagonist), RSG (PPAR agonist), and GW1516 (PPAR agonist) and AM580 (RARa agonist). The gene expression changes were detected globally by Affymetrix Human Genome U133 Plus 2.0 Arrays.
9-cis-13,14-Dihydroretinoic Acid Is an Endogenous Retinoid Acting as RXR Ligand in Mice.
Specimen part, Subject
View SamplesIn most embryos, the mid-blastula transition is a complex process featuring maternal RNA degradation, cell cycle pause, zygotic transcriptional activation and morphological changes. The nucleocytoplasmic (N/C) ratio has been proposed to control the multiple events at MBT. To understand the global transcriptional response to the changes of the N/C ratio, we profiled wild type and haploid embryos using cDNA microarrays at three developmental stages.
Coupling of zygotic transcription to mitotic control at the Drosophila mid-blastula transition.
No sample metadata fields
View SamplesKaposis sarcoma-associated hepesvirus (KSHV) encodes four genes with homology to human interferon regulatory factors (IRFs). One of these IRFs, the viral interferon regulatory factor 3 (vIRF-3) is expressed in latently infected PEL cells and required for their continuous proliferation. Moreover, vIRF-3 is known to be involved in modulation of the type I interferon response.
Kaposi's sarcoma-associated herpesvirus viral interferon regulatory factor 3 inhibits gamma interferon and major histocompatibility complex class II expression.
Specimen part, Cell line
View SamplesSystemic vaccination with the attenuated virus SIVmac239-Nef provides sterilizing or partial protection to rhesus monkeys challenged with WT SIV strains, providing important opportunities to study key immunological components of a protective host response. Here we show that intravenous vaccination with SIVmac239-Nef provides two potentially crucial immunological barriers localized at mucosal surfaces that correlate with the vaccines protective effects against WT SIVmac251 vaginal challenge: 1) a conditioned and coordinated response from the mucosal epithelium that blunts the early inflammatory and chemotactic signalling cascade that aids virus propagation and expansion; 2) early on-site generation/diversification of SIV-specific Abs from ectopic germinal center-like lymphoid aggregates. This unique host response to WT SIVmac251 in the female reproductive tract of SIVmac239-Nef-vaccinated animals points to a multi-layered strategy for a protective host response during immunodeficiency virus exposurerapid induction of humroal immunity at mucosal surfaces without the deleterious inflammatory side effects tied to innate recognition of virus. This vaccine-induced host response highlights potential key protective mechanisms needed for an effective HIV vaccine
Live simian immunodeficiency virus vaccine correlate of protection: immune complex-inhibitory Fc receptor interactions that reduce target cell availability.
Sex, Specimen part
View SamplesThe Early Growth Response (Egr) family of transcription factors consists of 4 members (Egr1-4) that are expressed in a wide variety of cell types. A large body of evidence point to a role for Egr transcription factors in growth, survival, and differentiation. A major unanswered question is whether Egr transcription factors serve similar functions in diverse cell types by activating a common set of target genes. Signal transduction cascades in neurons and lymphocytes show striking parallels. Activation of either cell type activates the Ras-MAPK pathway and, in parallel, leads to increases in intracellular calcium stimulating the calcineurin-NFAT pathway. In both cell types, the strength of the activation signal affects the cellular outcomes and very strong stimuli lead to cell death. Notably both these pathways converge on the induction of Egr genes. We believe that downstream targets of Egr transcription factors in lymphocytes may also be activated by Egr factors in activated neurons. There is precedence for common target gene activation in these two cell types: apoptosis in both activated T cells and methamphetamine stimulated neurons occurs via FasL induction by NFAT transcription factors. We propose to use developing T lymphocytes (thymocytes) as a model system for discovery of Egr-dependent target genes for several reasons. First, we have observed a prominent survival defect in thymocytes from mice deficient in both Egr1 and Egr3 (1/3 DKO) and a partial differention block in the immature double negative (DN) stage. In addition, thymocytes are an easily manipulatable cell type, and the DN subpopulation affected in 1/3 DKO mice can be isolated to very high purity. We anticipate that 1/3 DKO thymocytes will provide an excellent experimental system that will provide insight into Egr-dependent transcription in neuronal development, activation, and death.
Redundant role for early growth response transcriptional regulators in thymocyte differentiation and survival.
No sample metadata fields
View SamplesThe generation of induced pluripotent stem cells (iPSCs) and the direct conversion approach provide an invaluable resource of cells for disease modeling, drug screening, and patient-specific cell-based therapy. However, while iPSCs are stable and resemble ESCs in their transcriptome, methylome and function, the vast majority of the directly converted cells represent an incomplete reprogramming state as evident by their aberrant transcriptome and transgene dependency. This raises the question of whether complete and stable nuclear reprogramming can be achieved only in pluripotent cells. Here we demonstrate the generation of stable and fully functional induced trophoblast stem cells (iTSCs) by transient expression of Gata3, Tfap2c and Eomes. Similarly to iPSCs, iTSCs underwent a complete and stable reprogramming process as assessed by transcriptome and methylome analyses and functional assays such as the formation of hemorrhagic lesion and placenta contribution. Careful examination of the conversion process indicated that the cells did not go through a transient pluripotent state. These results suggest that complete nuclear reprograming can be attained in non-pluripotent cells. Overall design: Technical duplicates of 10 samples
Extensive Nuclear Reprogramming Underlies Lineage Conversion into Functional Trophoblast Stem-like Cells.
No sample metadata fields
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