The functional shift of quiescent endothelial cells into tip cells that migrate and stalk cells that proliferate is a key event during sprouting angiogenesis. We previously showed that the sialomucin CD34 is expressed in a small subset of cultured endothelial cells and that these cells extend filopodia: a hallmark of tip cells in vivo. In the present study, we characterized endothelial cells expressing CD34 in endothelial monolayers in vitro. We found that CD34-positive human umbilical vein endothelial cells show low proliferation activity and increased mRNA expression of all known tip cell markers, as compared to CD34- negative cells. Genome-wide mRNA profiling analysis of CD34-positive endothelial cells demonstrated enrichment for biological functions related to angiogenesis and migration, whereas CD34-negative cells were enriched for functions related to proliferation. In addition, we found an increase or decrease of CD34-positive cells in vitro upon exposure to stimuli that enhance or limit the number of tip cells in vivo, respectively. Our findings suggest cells with virtually all known properties of tip cells are present in vascular endothelial cell cultures and that they can be isolated based on expression of CD34. This novel strategy may open alternative avenues for future studies of molecular processes and functions in tip cells in angiogenesis.
CD34 marks angiogenic tip cells in human vascular endothelial cell cultures.
Specimen part, SubjectView Samples
Plants often face combinatorial stresses in their natural environment. Here arsenic (As) toxicity was combined with hypoxia (Hpx) in the roots of Arabidopsis thaliana as it often occurs in nature. The present work aimed to explore the effects of single and combined hypoxia and As stress applied at realistic stress levels to hydroponically grown A. thaliana.
Interference between arsenic-induced toxicity and hypoxia.
Specimen partView Samples
We report that whole body PRMT7-/- adult mice display a significant reduction in in muscle mass. RNA sequencing was performed to identify potential PRMT7 targets. We found that top canonical pathways affected by the loss of PRMT7 includes cell cycle and senescence. Overall design: RNA was extracted from tibialis anterior muscles harvested from 3 WT and 3 PRMT7 null mice at 8months. RNA sequencing was performed to compare mRNA in skeletal muscles between WT and KO mice.
PRMT7 Preserves Satellite Cell Regenerative Capacity.
Age, Specimen part, Cell line, SubjectView Samples
Diffuse intrinsic pontine glioma (DIPG) is a universally fatal malignancy of the childhood central nervous system, with a median overall survival of 9-11 months. We have previously shown that primary DIPG tissue contains numerous tumor-associated macrophages, and substantial work has demonstrated a significant pathological role for adult glioma-associated macrophages. However, work over the past decade has highlighted many molecular and genomic differences between pediatric and adult glioblastomas (GBM). Thus, we directly compared inflammatory characteristics of DIPG and adult GBM. We found that the leukocyte (CD45+) compartment in primary DIPG tissue samples is predominantly composed of CD11b+ macrophages, with very few CD3+ T-lymphocytes. In contrast, T-lymphocytes are more abundant in adult GBM tissue samples. RNA sequencing of macrophages isolated from primary tumor samples revealed that DIPG- and adult GBM-associated macrophages both express gene programs related to ECM remodeling and angiogenesis, but DIPG-associated macrophages express substantially fewer inflammatory factors than their adult GBM counterparts. Examining the secretome of glioma cells, we found that patient-derived DIPG cell cultures secrete markedly fewer cytokines and chemokines than patient-derived adult GBM cultures. Concordantly, bulk and single-cell RNA sequencing data indicates low to absent expression of chemokines and cytokines in DIPG. Together, these observations suggest that the inflammatory milieu of the DIPG tumor microenvironment is fundamentally different than adult GBM. The low intrinsic inflammatory signature of DIPG cells may contribute to the lack of lymphocytes and non-inflammatory phenotype of DIPG-associated microglia/macrophages. Understanding the glioma subtype-specific inflammatory milieu may inform the design and application of immunotherapy-based treatments. Overall design: RNA-seq of primary isolated microglia/macrophages from early post-mortem DIPG tissue samples, pediatric normal cortex, and adult GBM tissue samples. Libraries were sequenced on Illumina NextSeq 500, 1x75.
Non-inflammatory tumor microenvironment of diffuse intrinsic pontine glioma.
Sex, Specimen part, SubjectView Samples
To examine the role of retinol binding protein 7 (RBP7) in PPAR gamma mediated regulation of target gene expression in the carotid artery, RNA-Seq was used to quantitate gene expression in carotid artery from both wild-type and RBP7 knockout mice after ligand-mediated activation of PPAR gamma with Rosiglitazone. Overall design: Carotid artery were removed from wild-type (WT) and RBP7 knockout (KO) mice and treated with either Rosliglitazone (ROSI, 10 uM) or vehicle DMSO (CONT) for 24 hrs.
Retinol-binding protein 7 is an endothelium-specific PPAR<b>γ</b> cofactor mediating an antioxidant response through adiponectin.
Sex, Specimen part, Treatment, SubjectView Samples
DOT1L as methyltransferase of H3K79 is implicated in brian development. Here, we further defined DOT1L function in gene expression during cerebellar development using Microarrays. For that we generated Dot1l knockout mice using a Atoh-Cre driver line resulting in a Dot1l knockout within the cerebellum. The RNA of cerebellar tissue of the Dot1l knockout animals was thereby compared to controls. Additionally we compared the RNA levels of cultured CGNP and CGN samples treated with a DOT1L inhibitor versus DMSO treated cells. The data sets reveals potential new gene expression targets of DOT1L in vivo and in vitro, which ensure a correct development of the cerebellum.
Differential Methylation of H3K79 Reveals DOT1L Target Genes and Function in the Cerebellum In Vivo.
Specimen partView Samples
Huge efforts are made to engineer safe and efficient genome editing tools. An alternative might be the harnessing of ADAR-mediated RNA editing. We now present the engineering of chemically optimized antisense oligonucleotides that recruit endogenous human ADARs to edit endogenous transcripts in a simple and programmable way, an approach we refer to as RESTORE. Notably, RESTORE was markedly precise, and there was no evidence for perturbation of the natural editing homeostasis. We applied RESTORE to a panel of standard human cell lines, but also to several human primary cells including hepatocytes. In contrast to other RNA and DNA editing strategies, this approach requires only the administration of an oligonucleotide, circumvents the ectopic expression of proteins, and thus represents an attractive platform for drug development. In this respect we have shown the repair of the PiZZ mutation causing a1-antitrypsin deficiency and the editing of phosphotyrosine 701 in STAT1. Overall design: Identification of off-target editing events and Interferon-a influence in HeLa cell line transfected with an ASO for RNA editing by RNA-Seq, 2 samples (ASO +/- IFN) , 2 control sample (+/-IFN), 2 biologically independent experiments for each sample, 8 samples in total
Precise RNA editing by recruiting endogenous ADARs with antisense oligonucleotides.
Cell line, Treatment, SubjectView Samples
Background: The selective absorption of nutrients and other food constituents in the small intestine is mediated by a group of transport proteins and metabolic enzymes, often collectively called intestinal barrier proteins. An important receptor that mediates the effects of dietary lipids on gene expression is the peroxisome proliferator-activated receptor alpha (PPAR), which is abundantly expressed in enterocytes. In this study we examined the effects of acute nutritional activation of PPAR on expression of genes encoding intestinal barrier proteins. To this end we used triacylglycerols composed of identical fatty acids in combination with gene expression profiling in wild-type and PPAR-null mice. Treatment with the synthetic PPAR agonist WY14643 served as reference.
PPARalpha-mediated effects of dietary lipids on intestinal barrier gene expression.
No sample metadata fieldsView Samples