title: Identification of genes involved in VEGF-mediated vascular morphogenesis using embryonic stem cell-derived cystic embryoid bodies.
abstract: The vasculature forms during development via two processes, vasculogenesis and angiogenesis, in which vessels form de novo from angioblast precursors or as sprouts from pre-existing vessels, respectively. A common and critical aspect of both processes is vascular morphogenesis, which includes branching of endothelial cell cords and lumen formation. Although ample evidence support the central role of vascular endothelial growth factor (VEGF) in both vasculogenesis and angiogenesis, the role of VEGF in vascular morphogenesis is unclear and little is known about the regulation of vascular morphogenesis, in general. We have used the in vitro vessel differentiation system of embryonic stem (ES) cell-derived cystic embryonic bodies (CEB) as a model for studying VEGF-mediated vessel formation. Whereas CEB formed from wild-type ES cells make well-formed vessel-like structures, CEB derived from VEGF-null ES cells contain PECAM-1-positive endothelial cells, but these cells do not participate in vascular morphogenesis. Using gene expression microarray analysis to compare gene expression in these two systems, we have been able to identify many genes and novel ESTs that are downstream of VEGF function, and which may be involved in VEGF-mediated vascular morphogenesis including caveolin-1 and HEY-1. These results support using the CEB model, in combination with gene knockout ES cells, for studying vascular morphogenesis.
authors.affiliation: Department of Ophthalmology, Harvard Medical School and Schepens Eye Research Institute, Boston, MA, USA.
authors.forename: Yin-Shan
authors.initials: YS
authors.lastname: Ng
authors.forename: Markus
authors.initials: M
authors.lastname: Ramsauer
authors.forename: Robyn M B
authors.initials: RM
authors.lastname: Loureiro
authors.forename: Patricia A
authors.initials: PA
authors.lastname: D'Amore
mesh_terms: D000818:Animals; D051242:Caveolin 1; D022461:Caveolins / Q000235:genetics / Q000378:metabolism; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism; D002478:Cells, Cultured; D004622:Embryo, Mammalian / Q000098:blood supply / Q000502:physiology*; D005314:Embryonic and Fetal Development; D018507:Gene Expression Regulation, Developmental; D007150:Immunohistochemistry; D051379:Mice; D018345:Mice, Knockout; D023421:Models, Animal; D018919:Neovascularization, Physiologic / Q000235:genetics*; D020411:Oligonucleotide Array Sequence Analysis; D012333:RNA, Messenger / Q000032:analysis / Q000096:biosynthesis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013234:Stem Cells / Q000502:physiology*; D042461:Vascular Endothelial Growth Factor A / Q000172:deficiency / Q000235:genetics* / Q000378:metabolism
chemical_list: C495541:Cav1 protein, mouse; D051242:Caveolin 1; D022461:Caveolins; D018797:Cell Cycle Proteins; C120420:Hey1 protein, mouse; D012333:RNA, Messenger; D042461:Vascular Endothelial Growth Factor A; C467480:vascular endothelial growth factor A, mouse