Hts, the Drosophila homologue of Adducin, physically interacts with the transmembrane receptor Golden goal to guide photoreceptor axons.
Neurons steer their axons towards their proper targets during development. Molecularly, a number of guidance receptors have been identified. The transmembrane protein Golden goal (Gogo) was reported previously to guide photoreceptor (R) axons in the Drosophila visual system. Here, we show that Hts, the Drosophila homologue of Adducin, physically interacts with Gogo's cytoplasmic domain via its head-neck domain. hts null mutants show similar defects in R axon guidance as do gogo mutants. Rescue experiments suggest that the C-terminal tail but not the MARCKS homology domain of Hts is required. Overexpression of either gogo or hts causes abnormally thick swellings of R8 axons in the medulla, but if both are co-overexpressed, R8 axons appear normal and the amount of excessive Hts is reduced. Our results fit with a model where Gogo both positively and negatively regulates Hts that affects the Actin-Spectrin cytoskeleton in growth cone filopodia, thereby guiding R axons.
Max Planck Institute of Neurobiology, Martinsried, Germany.
Stephan
S
Ohler
Satoko
S
Hakeda-Suzuki
Takashi
T
Suzuki
D000818:Animals; D030801:Animals, Genetically Modified; D001369:Axons / Q000378:metabolism / Q000502:physiology*; D002148:Calmodulin-Binding Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D002465:Cell Movement / Q000235:genetics; D002478:Cells, Cultured; D004330:Drosophila / Q000235:genetics* / Q000378:metabolism / Q000502:physiology; D029721:Drosophila Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D005136:Eye Proteins / Q000235:genetics / Q000378:metabolism* / Q000502:physiology; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D008954:Models, Biological; D010786:Photoreceptor Cells / Q000378:metabolism / Q000502:physiology*; D011485:Protein Binding / Q000502:physiology; D055503:Protein Multimerization / Q000235:genetics; D017434:Protein Structure, Tertiary / Q000235:genetics / Q000502:physiology; D011554:Pseudopodia / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D011956:Receptors, Cell Surface / Q000235:genetics / Q000378:metabolism* / Q000502:physiology; D017385:Sequence Homology; D000099291:Adducins
D002148:Calmodulin-Binding Proteins; D029721:Drosophila Proteins; D005136:Eye Proteins; D008565:Membrane Proteins; D011956:Receptors, Cell Surface; D000099291:Adducins; C557406:Gogo protein, Drosophila; C108208:hts protein, Drosophila