Wnt5 signaling in vertebrate pancreas development
1 Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455 USA
2 Department of Molecular, Cellular, and Developmental Biology, University of California, Los Angeles, Los Angeles, CA 90095 USA
3 Department of Pediatrics, University of Minnesota, Minneapolis, MN 55455 USA
4 Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, MN 55455 USA
BMC Biology 2005, 3:23 doi:10.1186/1741-7007-3-23Published: 24 October 2005
Signaling by the Wnt family of secreted glycoproteins through their receptors, the frizzled (Fz) family of seven-pass transmembrane proteins, is critical for numerous cell fate and tissue polarity decisions during development.
We report a novel role of Wnt signaling in organogenesis using the formation of the islet during pancreatic development as a model tissue. We used the advantages of the zebrafish to visualize and document this process in living embryos and demonstrated that insulin-positive cells actively migrate to form an islet. We used morpholinos (MOs), sequence-specific translational inhibitors, and time-lapse imaging analysis to show that the Wnt-5 ligand and the Fz-2 receptor are required for proper insulin-cell migration in zebrafish. Histological analyses of islets in Wnt5a-/- mouse embryos showed that Wnt5a signaling is also critical for murine pancreatic insulin-cell migration.
Our results implicate a conserved role of a Wnt5/Fz2 signaling pathway in islet formation during pancreatic development. This study opens the door for further investigation into a role of Wnt signaling in vertebrate organ development and disease.