Project description:In mouse aorta endothelial cells, populations of endothelial vascular progenitor (EVP) and differentiated (D) cells could be identified by CD31 (lo/hi) and VEGFR2 (lo/hi) expression. These populations were FACS sorted and paired-end bulk RNA-sequencing was performed.
Project description:The aim of the experiment was to compare a newly defined population VE-Cadherin+GFP+ to control populations, VE-Cadherin- GFP+ and VE-Cadherin+GFP-.
Project description:The aim of this experiment was to investigate cellular heterogeneity of VE-Cadherin+ cells isolated from mouse E10.5 aorta-gonad-mesonephros region.
Project description:In order to identify genes regulated by VE-cadherin expression, we compared a mouse VE-cadherin null cell line (VEC null) with the same line reconstituted with VE-cadherin wild type cDNA (VEC positive). The morphological and functional properties of these cell lines were described previously [Lampugnani,M.G. et al. Contact inhibition of VEGF-induced proliferation requires vascular endothelial cadherin, beta-catenin, and the phosphatase DEP-1/CD148. J. Cell Biol. 161, 793-804 (2003)]. By Affymetrix gene expression analysis we found several genes up-regulated by VE-cadherin, among which claudin-5 reached remarkably high levels. The up-regulation of these genes required not only VE-cadherin expression but also cell confluence suggesting that VE-cadherin clustering at junctions was needed.
Project description:The shear stress-regulated lncRNA LASSIE interacts with junctional proteins (e.g. PECAM-1, which interacts with VE-cadherin) and influences endothelial barrier function. Here we characterize the remodeling of the VE-Cadherin complex by the lncRNA LASSIE. LASSIE silenced HUVECs were subjected to co-immunoprecipitation using an anti-VE-cadherin antibody. Differentially associated proteins were identified by Mass spectrometry. This analysis revealed a significantly decreased association of cytoskeleton-linked proteins with VE-cadherin after silencing of LASSIE. Functional assays confirmed this result and characterized LASSIE as a stabilizer of junctional complexes in endothelial cells, important for normal shear stress sensing and barrier function.
Project description:Vascular endothelial (VE-)cadherin is a homotypic adhesion protein that is expressed selectively by ECs in which it enables formation of tight vessels and regulation of vascular permeability. Since VE-cadherin is also strongly expressed in placental trophoblasts, it is a prime candidate for a molecular mechanism of vascular mimicry by those cells. Here, we show that the VE-cadherin is required for trophoblast migration and endovascular invasion into the maternal decidua. VE-cadherin deficiency results in loss of spiral artery remodeling due to a lack of invasive trophoblasts, leading to decreased flow of maternal blood into the placenta, fetal growth retardation and death. Loss of trophoblast invasion prevents decidualization, extracellular matrix remodeling, and immune cell clearance. These studies identify VE-cadherin as essential for trophoblast migration and coordination of decidual changes during endovascular invasion. They further suggest endothelial proteins such as VE-cadherin that are expressed by trophoblasts may play functionally distinct roles that do not simply mimic those in ECs.
Project description:We performed lineage tracing experiments using VE-Cadherin-Cre;LoxP-tdTomato mice. In these mice, endothelial cells (ECs) and their progeny are permanently marked by tdTomato fluorescence. We found that a substantial subset of stromal cells is derived from ECs, as indicated by their tdTomato expression. These findings support the notion that endothelial to mesenchymal transition (EndoMT) contributes to hematopoietic bone marrow niche formation in mice. Here we sought to determine the transcriptomic differences between endothelial-derived (tdTomato-positive) and non-endothelial-derived (tdTomato-negative) bone marrow stromal cells (BMSCs) and osteo/chondrolineage progenitor cells (OLCs). Murine niche populations were obtained from collagenased bone fraction of VE-Cadherin-Cre;LoxP-tdTomato mice at 3 weeks (n=2) or 11 weeks (n=2) of age. BMSCs (CD45-TER119-CD31-CD144-SCA-1+ CD51+ cells) and OLCs (CD45-TER119-CD31-CD144-Sca1-CD51+ cells) were FACS-purified and sequenced.
Project description:Endothelial cells (ECs) express two members of the cadherin family, VE- and N-cadherin. While VE-cadherin induces EC homotypic adhesion, N-cadherin function in ECs remains largely unknown. EC-specific inactivation of either VE- or N-cadherin leads to early foetal lethality suggesting that these cadherins play a non-redundant role in vascular development. Goal of this study was to further investigate this hypothesis analyzing both additive and divergent functions of the two cadherins in ECs.
Project description:Rationale: The mechanistic foundation of vascular maturation is still largely unknown. Several human pathologies are characterized by deregulated angiogenesis and unstable blood vessels. Solid tumours, for instance, get their nourishment from newly formed structurally abnormal vessels which present wide and irregular inter-endothelial junctions. Expression and clustering of the main endothelial-specific adherens junction protein, vascular endothelial (VE)-cadherin (VEC), upregulate genes with key roles in endothelial differentiation and stability. Objective: We aim at understanding the molecular mechanisms through which VEC triggers the expression of a set of genes involved in endothelial differentiation and vascular stabilization. Methods and Results: We compared a VEC-null cell line with the same line reconstituted with VEC wild type cDNA. VEC expression and clustering upregulated endothelial-specific genes with key roles in vascular stabilization including claudin-5, Vascular Endothelial-Protein Tyrosine Phosphatase (VE-PTP) and von Willebrand factor (vWf). Mechanistically VEC exerts this effect by inhibiting Polycomb protein activity on the specific gene promoters. This is achieved by preventing nuclear translocation of FoxO1 and β-catenin, which contribute to Polycomb repressive complex-2 (PRC2) binding to promoter regions of claudin-5, VE-PTP and vWf. VE-cadherin/β-catenin complex also sequesters a core subunit of PRC2 (Ezh2) at the cell membrane, preventing its nuclear translocation. Inhibition of Ezh2/VE-cadherin association increases Ezh2 recruitment to claudin-5, VE-PTP and vWf promoters, causing gene downregulation. RNAseq comparison of VEC-null and VEC-positive cells suggested a more general role of VE-cadherin in activating endothelial genes and triggering a vascular stability-related gene expression program. In pathological angiogenesis of human ovarian carcinomas, reduced VEC expression paralleled decreased levels of Claudin-5 and VE-PTP. Conclusions: These data extend the knowledge of Polycomb-mediated regulation of gene expression to endothelial cell differentiation and vessel maturation. The identified mechanism opens novel therapeutic opportunities to modulate endothelial gene expression and induce vascular normalization through pharmacological inhibition of the Polycomb-mediated repression system. Keywords: Polycomb, endothelial cells, VE-cadherin, vessel maturation, vascular biology, vascular permeability, cell signalling, epigenetics, gene regulation. Downloaded from http://circres.ahajour Conclusions: These data extend the knowledge of Polycomb-mediated regulation of gene expression to endothelial cell differentiation and vessel maturation. The identified mechanism opens novel therapeutic opportunities to modulate endothelial gene expression and induce vascular normalization through pharmacological inhibition of the Polycomb-mediated repression system