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 SamplesHuman umbilical vein endothelial cells (HUVECs) were incubated for 48 h after transfection of scrambled siRNA or siRNA targeting Jmjd6 .
Jumonji domain-containing protein 6 (Jmjd6) is required for angiogenic sprouting and regulates splicing of VEGF-receptor 1.
Specimen part, Treatment
View SamplesPulmonary hypertension is a frequent consequence of left heart disease and congestive heart failure (CHF) and causes extensive lung vascular remodelling which leads to right ventricular failure. Functional genomics underlying this structural remodelling are unknown but present potential targets for novel therapeutic strategies. We used microarrays to detail the gene expression underlying vascular remodeling in the pathogenesis of pulmonary hypertension and identified distinct classes of up-regulated genes during this process.
Mast cells promote lung vascular remodelling in pulmonary hypertension.
Specimen part, Disease, Disease stage
View SamplesThis SuperSeries is composed of the SubSeries listed below.
DAF-16/FOXO and EGL-27/GATA promote developmental growth in response to persistent somatic DNA damage.
Treatment
View SamplesGenome maintenance defects cause complex disease phenotypes characterized by developmental failure, cancer susceptibility and premature aging. It remains poorly understood how DNA damage responses function during organismal development and maintain tissue functionality when DNA damage accumulates with aging. Here we show that the FoxO transcription factor DAF-16 is activated in response to DNA damage during development while the DNA damage responsiveness of DAF-16 declines with aging. We find that in contrast to its established role in mediating starvation arrest, DAF-16 alleviates DNA damage induced developmental arrest and even in the absence of DNA repair promotes developmental growth and enhances somatic tissue functionality. We demonstrate that the GATA transcription factor EGL-27 co-regulates DAF-16 target genes in response to DNA damage and together with DAF-16 promotes developmental growth. We propose that EGL-27/GATA activity specifies DAF-16 mediated DNA damage responses to enable developmental progression and to prolong tissue functioning when DNA damage persists.
DAF-16/FOXO and EGL-27/GATA promote developmental growth in response to persistent somatic DNA damage.
Treatment
View SamplesGenome maintenance defects cause complex disease phenotypes characterized by developmental failure, cancer susceptibility and premature aging. It remains poorly understood how DNA damage responses function during organismal development and maintain tissue functionality when DNA damage accumulates with aging. Here we show that the FoxO transcription factor DAF-16 is activated in response to DNA damage during development while the DNA damage responsiveness of DAF-16 declines with aging. We find that in contrast to its established role in mediating starvation arrest, DAF-16 alleviates DNA damage induced developmental arrest and even in the absence of DNA repair promotes developmental growth and enhances somatic tissue functionality. We demonstrate that the GATA transcription factor EGL-27 co-regulates DAF-16 target genes in response to DNA damage and together with DAF-16 promotes developmental growth. We propose that EGL-27/GATA activity specifies DAF-16 mediated DNA damage responses to enable developmental progression and to prolong tissue functioning when DNA damage persists.
DAF-16/FOXO and EGL-27/GATA promote developmental growth in response to persistent somatic DNA damage.
Treatment
View SamplesNucleosomal incorporation of specialized histone variants is an important mechanism to generate different functional chromatin states. Here we report the identification and characterization of two novel primate-specific histone H3 variants, H3.X and H3.Y. Their mRNAs are found in certain human cell lines, in addition to several normal and malignant human tissues. In keeping with their primate-specificity, H3.X and H3.Y are detected in different brain regions. Transgenic H3.X and H3.Y proteins are stably incorporated into chromatin in a similar fashion to the known H3 variants. Importantly, we demonstrate biochemically and by mass spectrometry that endogenous posttranslationally modified H3.Y protein exists in vivo, and that stress-stimuli, such as starvation and cellular density, increase the abundance of H3.Y-expressing cells. Global transcriptome analysis revealed that knock-down of H3.Y affects cell growth and leads to changes in the expression of many genes involved in cell cycle control. Thus, H3.Y is a novel histone variant involved in the regulation of cellular responses to outside stimuli.
Identification and characterization of two novel primate-specific histone H3 variants, H3.X and H3.Y.
Cell line
View SamplesWe analyzed gene expression profiles of IL-18 generated murine NK cells in comparison to unstimulated, freshly isolated splenic NK cells.
Immunoregulatory natural killer cells suppress autoimmunity by down-regulating antigen-specific CD8+ T cells in mice.
Specimen part, Treatment
View SamplesmRNA sequencing was used to identify genome wide transcriptional changes occuring in fly heads in response to spermidine feeding. This study shed light on the molecular mechanisms through wich spermidine can protect against age-dependent memory impairment. Overall design: mRNA profiles from 3 and 10 day old Drosophila melanogaster heads were generated in duplicate by deep sequencing using Illumina GAIIx. mRNA profiles from flies that were fed food with 5mM spermidine were compared to profiles from flies that had no spermidine in thier food.
Restoring polyamines protects from age-induced memory impairment in an autophagy-dependent manner.
Age, Specimen part, Subject
View SamplesUniparental parthenotes are considered an unwanted byproduct of in vitro fertilization. In utero parthenote development is severely compromised by defective organogenesis and in particular by defective cardiogenesis. Although developmentally compromised, apparently pluripotent stem cells can be derived from parthenogenetic blastocysts. Here we hypothesized that nonembryonic parthenogenetic stem cells (PSCs) can be directed toward the cardiac lineage and applied to tissue-engineered heart repair. We first confirmed similar fundamental properties in murine PSCs and embryonic stem cells (ESCs), despite notable differences in genetic (allelic variability) and epigenetic (differential imprinting) characteristics. Haploidentity of major histocompatibility complexes (MHCs) in PSCs is particularly attractive for allogeneic cell-based therapies. Accordingly, we confirmed acceptance of PSCs in MHC-matched allotransplantation. Cardiomyocyte derivation from PSCs and ESCs was equally effective. The use of cardiomyocyte-restricted GFP enabled cell sorting and documentation of advanced structural and functional maturation in vitro and in vivo. This included seamless electrical integration of PSC-derived cardiomyocytes into recipient myocardium. Finally, we enriched cardiomyocytes to facilitate engineering of force-generating myocardium and demonstrated the utility of this technique in enhancing regional myocardial function after myocardial infarction. Collectively, our data demonstrate pluripotency, with unrestricted cardiogenicity in PSCs, and introduce this unique cell type as an attractive source for tissue-engineered heart repair.
Parthenogenetic stem cells for tissue-engineered heart repair.
Specimen part
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