title: Pou5f1-dependent EGF expression controls E-cadherin endocytosis, cell adhesion, and zebrafish epiboly movements.
abstract: Initiation of motile cell behavior in embryonic development occurs during late blastula stages when gastrulation begins. At this stage, the strong adhesion of blastomeres has to be modulated to enable dynamic behavior, similar to epithelial-to-mesenchymal transitions. We show that, in zebrafish maternal and zygotic (MZ)spg embryos mutant for the stem cell transcription factor Pou5f1/Oct4, which are severely delayed in the epiboly gastrulation movement, all blastomeres are defective in E-cadherin (E-cad) endosomal trafficking, and E-cad accumulates at the plasma membrane. We find that Pou5f1-dependent control of EGF expression regulates endosomal E-cad trafficking. EGF receptor may act via modulation of p120 activity. Loss of E-cad dynamics reduces cohesion of cells in reaggregation assays. Quantitative analysis of cell behavior indicates that dynamic E-cad endosomal trafficking is required for epiboly cell movements. We hypothesize that dynamic control of E-cad trafficking is essential to effectively generate new adhesion sites when cells move relative to each other.
authors.affiliation: Developmental Biology, Institute Biology I, Faculty of Biology, Albert-Ludwigs-University Freiburg, D-79104 Freiburg, Germany.
authors.forename: Sungmin
authors.initials: S
authors.lastname: Song
authors.forename: Stephanie
authors.initials: S
authors.lastname: Eckerle
authors.forename: Daria
authors.initials: D
authors.lastname: Onichtchouk
authors.forename: James A
authors.initials: JA
authors.lastname: Marrs
authors.forename: Roland
authors.initials: R
authors.lastname: Nitschke
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Driever
mesh_terms: D000818:Animals; D015153:Blotting, Western; D015820:Cadherins / Q000235:genetics / Q000378:metabolism*; D002448:Cell Adhesion / Q000502:physiology*; D002465:Cell Movement / Q000502:physiology; D004625:Embryo, Nonmammalian / Q000166:cytology / Q000378:metabolism; D004705:Endocytosis / Q000502:physiology*; D004815:Epidermal Growth Factor / Q000378:metabolism*; D054262:Gastrulation / Q000502:physiology*; D018507:Gene Expression Regulation, Developmental; D018773:Genes, erbB-1; D007124:Immunoenzyme Techniques; D050814:Octamer Transcription Factor-3 / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction; D015027:Zebrafish / Q000196:embryology / Q000235:genetics / Q000378:metabolism*; D029961:Zebrafish Proteins / Q000235:genetics / Q000378:metabolism*; D020696:rab5 GTP-Binding Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: D015820:Cadherins; D050814:Octamer Transcription Factor-3; C085437:Pou5f3 protein, zebrafish; D012333:RNA, Messenger; D029961:Zebrafish Proteins; D004815:Epidermal Growth Factor; C505379:Rab5c protein, zebrafish; D020696:rab5 GTP-Binding Proteins