title: A truncation allele in vascular endothelial growth factor c reveals distinct modes of signaling during lymphatic and vascular development.
abstract: Vascular endothelial growth factor C (Vegfc) is a secreted protein that guides lymphatic development in vertebrate embryos. However, its role during developmental angiogenesis is not well characterized. Here, we identify a mutation in zebrafish vegfc that severely affects lymphatic development and leads to angiogenesis defects on sensitized genetic backgrounds. The um18 mutation prematurely truncated Vegfc, blocking its secretion and paracrine activity but not its ability to activate its receptor Flt4. When expressed in endothelial cells, vegfc(um18) could not rescue lymphatic defects in mutant embryos, but induced ectopic blood vessel branching. Furthermore, vegfc-deficient endothelial cells did not efficiently contribute to tip cell positions in developing sprouts. Computational modeling together with assessment of endothelial cell dynamics by time-lapse analysis suggested that an autocrine Vegfc/Flt4 loop plays an important role in migratory persistence and filopodia stability during sprouting. Our results suggest that Vegfc acts in two distinct modes during development: as a paracrine factor secreted from arteries to guide closely associated lymphatic vasculature and as an autocrine factor to drive migratory persistence during angiogenesis.
authors: Program in Gene Function and Expression, University of Massachusetts Medical School, Worcester, MA 01605, USA.
authors: Jacques A
authors: JA
authors: Villefranc
authors: Stefania
authors: S
authors: Nicoli
authors: Katie
authors: K
authors: Bentley
authors: Michael
authors: M
authors: Jeltsch
authors: Georgia
authors: G
authors: Zarkada
authors: John C
authors: JC
authors: Moore
authors: Holger
authors: H
authors: Gerhardt
authors: Kari
authors: K
authors: Alitalo
authors: Nathan D
authors: ND
authors: Lawson
mesh_terms: D000483:Alleles; D000818:Animals; D030801:Animals, Genetically Modified; D019898:Autocrine Communication / Q000235:genetics / Q000502:physiology; D001808:Blood Vessels / Q000196:embryology* / Q000254:growth & development; D002465:Cell Movement / Q000235:genetics / Q000502:physiology; D018389:Codon, Nonsense / Q000502:physiology; D004625:Embryo, Nonmammalian; D005260:Female; D008208:Lymphatic System / Q000196:embryology* / Q000254:growth & development; D051379:Mice; D018345:Mice, Knockout; D018919:Neovascularization, Physiologic / Q000235:genetics / Q000502:physiology; D019899:Paracrine Communication / Q000235:genetics / Q000502:physiology; D020033:Protein Isoforms / Q000235:genetics / Q000502:physiology; D015398:Signal Transduction / Q000235:genetics; D042582:Vascular Endothelial Growth Factor C / Q000235:genetics* / Q000502:physiology*; D015027:Zebrafish / Q000196:embryology / Q000235:genetics; D029961:Zebrafish Proteins / Q000235:genetics* / Q000502:physiology*
chemical_list: D018389:Codon, Nonsense; D020033:Protein Isoforms; D042582:Vascular Endothelial Growth Factor C; D029961:Zebrafish Proteins; C493178:vascular endothelial growth factor C, zebrafish