Project description:Endothelial differentiation occurs during normal vascular development in the developing embryo. Mouse embryonic stem (ES) cells were used to further define the molecular mechanisms of endothelial differentiation. By flow cytometry a population of VEGF-R2 positive cells was identified as early as 2.5 days after differentiation of ES cells, and a subset of VEGF-R2 + cells, that were CD41+ positive at 3.5 days. A separate population of VEGF-R2+ stem cells expressing the endothelial-specific marker CD144 (VE-cadherin) was also identified at this same time point. Microarray analysis of >45,000 transcripts was performed on RNA obtained from cells expressing VEGF-R2, CD41, and CD144. Experiment Overall Design: We identified four populations of cells; cells expressing VEGF-R2 (day 2.5), CD41 expressing cells (day 3.5), cells expressing CD144 (VE-Cadherin, day 3.5), and cells expressing CD144 (day 6.5). In addition to this, we have also obtained the negative control cells at each time such as VEGF-R2 (day 2.5) negative, CD41 negative (day 3.5), CD144 negative (VE-Cadherin, day 3.5), and negative CD144 (day 6.5). RNA for the microarray experiments were obtained in duplicate from two separately conducted experiments using the murine embryonic stem cells..
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:RNA-seq of endothelial (Endo), Pre-hematopoietic progenitor cells (Pre-HPCs) and hematopoietic progenitors (HP) derived from the in-vitro hematopoietic differentiation of mouse Embryonic Stem Cells (mESCs) harboring a biallelic inactivating deletion of the endogenous Tal1 gene, and a construct for the dox-induced expression of the hematopoietic genes Tal1, Lyl1 and Lmo2 (i3TFs Tal1Δ/Δ mESCs). i: inducible. TFs: transcription factors. Cells were treated with dox at one (Dox Unt) or two (Dox Dox) time-points during hematopoietic differentiation to inducibly express the 3TFs. Sequenced cell populations were purified by FACS sorting based on the cell-surface expression of the endothelial marker VE-CADHERIN and the hematopoietic marker CD41. Endo: VE-CADHERIN+CD41- Pre-HPCs: VE-CADHERIN+CD41+ HP: VE-CADHERIN-CD41+
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: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: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. The three endothelial cell lines were cultured. Total RNA was extracted using commercial homogenization (QIAshredder) and purification (RNeasy Mini Kit) reagents (Qiagen). Quality control (QC) of the RNA samples was performed using an Agilent Bioanalyzer 2100 (Agilent Technologies). Two different RNA extractions were processed for each of the cell lines under analysis, and each sample was labelled and hybridized to a Mouse Gene 1.0 ST Genechip array according to the manufacturer’s specifications (Affymetrix Inc). Data were analysed using Partek Genomics Suite v6.3 software (RMA algorithm). Differentially expressed genes were identified through ANOVA, using a fold change cutoff >2 and a p-value of 0.05.
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: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:Endothelial differentiation occurs during normal vascular development in the developing embryo. Mouse embryonic stem (ES) cells were used to further define the molecular mechanisms of endothelial differentiation. By flow cytometry a population of VEGF-R2 positive cells was identified as early as 2.5 days after differentiation of ES cells, and a subset of VEGF-R2 + cells, that were CD41+ positive at 3.5 days. A separate population of VEGF-R2+ stem cells expressing the endothelial-specific marker CD144 (VE-cadherin) was also identified at this same time point. Microarray analysis of >45,000 transcripts was performed on RNA obtained from cells expressing VEGF-R2, CD41, and CD144. Keywords: expression analysis