RRC ID 5645
Author Sakurai M, Aoki T, Yoshikawa S, Santschi LA, Saito H, Endo K, Ishikawa K, Kimura K, Ito K, Thomas JB, Hama C.
Title Differentially expressed Drl and Drl-2 play opposing roles in Wnt5 signaling during Drosophila olfactory system development.
Journal J. Neurosci.
Abstract In Drosophila, odor information received by olfactory receptor neurons (ORNs) is processed by glomeruli, which are organized in a stereotypic manner in the antennal lobe (AL). This glomerular organization is regulated by Wnt5 signaling. In the embryonic CNS, Wnt5 signaling is transduced by the Drl receptor, a member of the Ryk family. During development of the olfactory system, however, it is antagonized by Drl. Here, we identify Drl-2 as a receptor mediating Wnt5 signaling. Drl is found in the neurites of brain cells in the AL and specific glia, whereas Drl-2 is predominantly found in subsets of growing ORN axons. A drl-2 mutation produces only mild deficits in glomerular patterning, but when it is combined with a drl mutation, the phenotype is exacerbated and more closely resembles the Wnt5 phenotype. Wnt5 overexpression in ORNs induces aberrant glomeruli positioning. This phenotype is ameliorated in the drl-2 mutant background, indicating that Drl-2 mediates Wnt5 signaling. In contrast, forced expression of Drl-2 in the glia of drl mutants rescues the glomerular phenotype caused by the loss of antagonistic Drl function. Therefore, Drl-2 can also antagonize Wnt5 signaling. Additionally, our genetic data suggest that Drl localized to developing glomeruli mediates Wnt5 signaling. Thus, these two members of the Ryk family are capable of carrying out a similar molecular function, but they can play opposing roles in Wnt5 signaling, depending on the type of cells in which they are expressed. These molecules work cooperatively to establish the olfactory circuitry in Drosophila.
Volume 29(15)
Pages 4972-80
Published 2009-4-15
DOI 10.1523/JNEUROSCI.2821-08.2009
PII 29/15/4972
PMID 19369566
PMC PMC2749065
MeSH Animals Animals, Genetically Modified Drosophila Drosophila Proteins / biosynthesis Drosophila Proteins / genetics Drosophila Proteins / physiology* Gene Expression Regulation, Developmental / physiology* Mutation Neuroglia / metabolism Neuroglia / physiology Olfactory Pathways / growth & development* Proto-Oncogene Proteins / biosynthesis Proto-Oncogene Proteins / genetics Proto-Oncogene Proteins / physiology* Receptor Protein-Tyrosine Kinases / biosynthesis Receptor Protein-Tyrosine Kinases / genetics Receptor Protein-Tyrosine Kinases / physiology* Signal Transduction / genetics Signal Transduction / physiology* Smell / physiology* Wnt Proteins / biosynthesis Wnt Proteins / genetics Wnt Proteins / physiology*
IF 5.971
Times Cited 19