ZFIN ID: ZDB-PUB-020913-5
Specification of an anterior neuroectoderm patterning by Frizzled8a-mediated Wnt8b signalling during late gastrulation in zebrafish
Kim, S.-H., Shin, J., Park, H.-C., Yeo, S.-Y., Hong, S.-K., Han, S., Rhee, M., Kim, C.-H., Chitnis, A.B., and Huh, T.-L.
Date: 2002
Source: Development (Cambridge, England)   129(19): 4443-4455 (Journal)
Registered Authors: Chitnis, Ajay, Hong, Sung-Kook, Huh, Tae-Lin, Kim, Cheol-Hee, Kim, Seok-Hyung, Park, Hae-Chul, Shin, Jimann, Yeo, Sang-Yeob
Keywords: Fz8a, Wnt8b, Anterior neuroectoderm, Brain patterning, Eye primordia, Diencephalon, Midbrain, Zebrafish
MeSH Terms:
  • Animals
  • Body Patterning/physiology*
  • Brain/embryology*
  • Ectoderm
  • Eye/embryology
  • Gastrula/physiology
  • Gene Expression
  • Gene Targeting
  • Genes, Overlapping
  • Proteins/genetics
  • Proteins/metabolism*
  • Proto-Oncogene Proteins/metabolism
  • Receptors, Cell Surface/genetics
  • Receptors, Cell Surface/metabolism*
  • Signal Transduction*
  • Wnt Proteins
  • Xenopus Proteins*
  • Zebrafish/embryology
  • Zebrafish/genetics
  • Zebrafish Proteins*
PubMed: 12223403
Wnts have been shown to provide a posteriorizing signal that has to be repressed in the anterior neuroectoderm for normal anteroposterior (AP) patterning. We have previously identified a zebrafish frizzled8a (fz8a) gene expressed in the presumptive anterior neuroectoderm as well as prechordal plate at the late gastrula stage. We have investigated the role of Fz8a-mediated Wnt8b signalling in anterior brain patterning in zebrafish. We show that in zebrafish embryos: (1) Wnt signalling has at least two different stage-specific posteriorizing activities in the anterior neuroectoderm, one before mid-gastrulation and the other at late gastrulation; (2) Fz8a plays an important role in mediating anterior brain patterning; (3) Wnt8b and Fz8a can functionally interact to transmit posteriorizing signals that determine the fate of the posterior diencephalon and midbrain in late gastrula embryos; and (4) Wnt8b can suppress fz8a expression in the anterior neuroectoderm and potentially affect the level and/or range of Wnt signalling. In conclusion, we suggest that a gradient of Fz8a-mediated Wnt8b signalling may play crucial role in patterning the posterior diencephalon and midbrain regions in the late gastrula.