title: Notch hyper-activation drives trans-differentiation of hESC-derived endothelium.
abstract: During development, endothelial cells (EC) display tissue-specific attributes that are unique to each vascular bed, as well as generic signaling mechanisms that are broadly applied to create a patent circulatory system. We have previously utilized human embryonic stem cells (hESC) to generate tissue-specific EC sub-types (Rafii et al., 2013) and identify pathways that govern growth and trans-differentiation potential of hESC-derived ECs (James et al., 2010). Here, we elucidate a novel Notch-dependent mechanism that induces endothelial to mesenchymal transition (EndMT) in confluent monolayer cultures of hESC-derived ECs. We demonstrate density-dependent induction of EndMT that can be rescued by the Notch signaling inhibitor DAPT and identify a positive feedback signaling mechanism in hESC-ECs whereby trans-activation of Notch by DLL4 ligand induces elevated expression and surface presentation of DLL4. Increased Notch activation in confluent hESC-EC monolayer cultures induces areas of EndMT containing transitional cells that are marked by increased Jagged1 expression and reduced Notch signal integration. Jagged1 loss of function in monolayer hESC-ECs induces accelerated feedback stimulation of Notch signaling, increased expression of cell-autonomous, cis-inhibitory DLL4, and EndMT. These data elucidate a novel interplay of Notch ligands in modulating pathway activation during both expansion and EndMT of hESC-derived ECs.
authors.affiliation: Center for Reproductive Medicine and Infertility, Weill Cornell Medical College, New York, NY 10065, United States.
authors.forename: David
authors.initials: D
authors.lastname: Reichman
authors.affiliation: Center for Reproductive Medicine and Infertility, Weill Cornell Medical College, New York, NY 10065, United States.
authors.forename: Limor
authors.initials: L
authors.lastname: Man
authors.affiliation: Center for Reproductive Medicine and Infertility, Weill Cornell Medical College, New York, NY 10065, United States.
authors.forename: Laura
authors.initials: L
authors.lastname: Park
authors.affiliation: Tri-Institutional Stem Cell Derivation Laboratory, Weill Cornell Medical College, New York, NY 10065, United States.
authors.forename: Raphael
authors.initials: R
authors.lastname: Lis
authors.affiliation: Center for Reproductive Medicine and Infertility, Weill Cornell Medical College, New York, NY 10065, United States.
authors.forename: Jeannine
authors.initials: J
authors.lastname: Gerhardt
authors.affiliation: Center for Reproductive Medicine and Infertility, Weill Cornell Medical College, New York, NY 10065, United States.
authors.forename: Zev
authors.initials: Z
authors.lastname: Rosenwaks
authors.affiliation: Center for Reproductive Medicine and Infertility, Weill Cornell Medical College, New York, NY 10065, United States; Tri-Institutional Stem Cell Derivation Laboratory, Weill Cornell Medical College, New York, NY 10065, United States. Electronic address: djj2001@med.cornell.edu.
authors.forename: Daylon
authors.initials: D
authors.lastname: James
mesh_terms: D001549:Benzamides / Q000494:pharmacology; D054338:Cell Transdifferentiation; D002478:Cells, Cultured; D003959:Diamines / Q000494:pharmacology; D004149:Dioxoles / Q000494:pharmacology; D042783:Endothelial Cells / Q000166:cytology / Q000378:metabolism*; D000066449:Human Embryonic Stem Cells / Q000166:cytology* / Q000378:metabolism; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000378:metabolism; D000072100:Jagged-1 Protein / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D008565:Membrane Proteins / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000378:metabolism; D008856:Microscopy, Fluorescence; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000378:metabolism; D051880:Receptors, Notch / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction / Q000187:drug effects; D013844:Thiazoles / Q000494:pharmacology; D015533:Transcriptional Activation
chemical_list: C000612000:24-diamino-5-phenylthiazole; C459179:4-(5-benzo(1,3)dioxol-5-yl-4-pyridin-2-yl-1H-imidazol-2-yl)benzamide; D001549:Benzamides; D003959:Diamines; D004149:Dioxoles; D047908:Intracellular Signaling Peptides and Proteins; D000072100:Jagged-1 Protein; D008565:Membrane Proteins; D034741:RNA, Small Interfering; D051880:Receptors, Notch; D013844:Thiazoles; C064045:delta protein