The Role(s) of Heparan Sulfate Proteoglycan(s) in the wnt-1 Signaling Pathway
Abstract
I have identified A Drosophila gene, sulfateless (sfl) which encodes the homologue of vertebrate heparan/haparin sulfate N-deacetylase/N-sulfotransferase. This enzyme is essential for the modification and the biological activity of heparan sulfate proteoglycans (HSPG). I find that in the absence of both maternal and zygotic activities of this gene, mutant embryos develop with segment polarity phenotypes reminiscent to loss of either Wingless (Wg) or Hedgehog signaling. To analyze the function of Sfl enzymes in a specific cell-cell interaction process, I have focused my analysis on the requirement for these enzymes during Wg signaling. I report that sfl mutation impair Wg signaling during both embryonic and imaginal discs development, suggesting that HSPGs contribute to the reception of Wg. Sfl acts non cell-autonomously in Wg signaling and overexpression of Wg can bypass the requirement for this enzyme suggesting that HSPGs modulate Wg signaling, possibly by facilitating the binding of Wg to its receptor. These findings thus provide strong genetic evidence that HSPG is critical for signaling by Wg.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 1998
- Accession Number
- ADB244768
Entities
People
- Xinhua Lin
Organizations
- Harvard Medical School