title: A Novel Role for VICKZ Proteins in Maintaining Epithelial Integrity during Embryogenesis.
abstract: BACKGROUND
  VICKZ (IGF2BP1,2,3/ZBP1/Vg1RBP/IMP1,2,3) proteins bind RNA and help regulate many RNA-mediated processes. In the midbrain region of early chick embryos, VICKZ is expressed in the neural folds and along the basal surface of the neural epithelium, but, upon neural tube closure, is down-regulated in prospective cranial neural crest (CNC) cells, concomitant with their emigration and epithelial-to-mesenchymal transition (EMT). Electroporation of constructs that modulate cVICKZ expression demonstrates that this down-regulation is both necessary and sufficient for CNC EMT. These results suggest that VICKZ down-regulation in CNC cell-autonomously promotes EMT and migration. Reduction of VICKZ throughout the embryo, however, inhibits CNC migration non-cell-autonomously, as judged by transplantation experiments in Xenopus embryos.
  
  
  CONCLUSIONS
  Given the positive role reported for VICKZ proteins in promoting cell migration of chick embryo fibroblasts and many types of cancer cells, we have begun to look for specific mRNAs that could mediate context-specific differences. We report here that the laminin receptor, integrin alpha 6, is down-regulated in the dorsal neural tube when CNC cells emigrate, this process is mediated by cVICKZ, and integrin alpha 6 mRNA is found in VICKZ ribonucleoprotein complexes. Significantly, prolonged inhibition of cVICKZ in either the neural tube or the nascent dermomyotome sheet, which also dynamically expresses cVICKZ, induces disruption of these epithelia. These data point to a previously unreported role for VICKZ in maintaining epithelial integrity.
authors: Department of Developmental Biology and Cancer Research, The Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel.
authors: Michal Shoshkes
authors: MS
authors: Carmel
authors: Department of Medical Neurobiology, IMRIC, The Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel.
authors: Nitza
authors: N
authors: Kahane
authors: Department of Developmental Biology and Cancer Research, The Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel.
authors: Froma
authors: F
authors: Oberman
authors: Department of Developmental Biology and Cancer Research, The Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel.
authors: Rachel
authors: R
authors: Miloslavski
authors: Koret School of Veterinary Medicine, The Hebrew University of Jerusalem, The Robert H. Smith Faculty of Agriculture, Food and Environment, 76100, Rehovot, Israel.
authors: Dalit
authors: D
authors: Sela-Donenfeld
authors: Department of Medical Neurobiology, IMRIC, The Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel.
authors: Chaya
authors: C
authors: Kalcheim
authors: Department of Developmental Biology and Cancer Research, The Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel.
authors: Joel K
authors: JK
authors: Yisraeli
mesh_terms: D000818:Animals; D030161:Avian Proteins / Q000235:genetics / Q000378:metabolism*; D002465:Cell Movement / Q000502:physiology*; D002642:Chick Embryo; D047108:Embryonic Development / Q000502:physiology*; D058750:Epithelial-Mesenchymal Transition / Q000502:physiology*; D004848:Epithelium / Q000196:embryology; D005347:Fibroblasts / Q000166:cytology / Q000378:metabolism; D016601:RNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D029867:Xenopus Proteins / Q000235:genetics / Q000378:metabolism*; D014982:Xenopus laevis
chemical_list: D030161:Avian Proteins; D016601:RNA-Binding Proteins; D029867:Xenopus Proteins