Dendrites of distinct classes of Drosophila sensory neurons show different capacities for homotypic repulsion.
BACKGROUND
Understanding how dendrites establish their territory is central to elucidating how neuronal circuits are built. Signaling between dendrites is thought to be important for defining their territories; however, the strategies by which different types of dendrites communicate are poorly understood. We have shown previously that two classes of Drosophila peripheral da sensory neurons, the class III and class IV neurons, provide complete and independent tiling of the body wall. By contrast, dendrites of class I and class II neurons do not completely tile the body wall, but they nevertheless occupy nonoverlapping territories.


RESULTS
By developing reagents to permit high-resolution studies of dendritic tiling in living animals, we demonstrate that isoneuronal and heteroneuronal class IV dendrites engage in persistent repulsive interactions. In contrast to the extensive dendritic exclusion shown by class IV neurons, duplicated class III neurons showed repulsion only at their dendritic terminals. Supernumerary class I and class II neurons innervated completely overlapping regions of the body wall, and this finding suggests a lack of like-repels-like behavior.


CONCLUSIONS
These data suggest that repulsive interactions operate between morphologically alike dendritic arbors in Drosophila. Further, Drosophila da sensory neurons appear to exhibit at least three different types of class-specific dendrite-dendrite interactions: persistent repulsion by all branches, repulsion only by terminal dendrites, and no repulsion.
Grueber
Wesley B
WB
Howard Hughes Medical Institute, Departments of Physiology and Biochemistry, University of California-San Francisco, 533 Parnassus Avenue, Room U226, San Francisco, CA 94143, USA.
Ye
Bing
B
Moore
Adrian W
AW
Jan
Lily Y
LY
Jan
Yuh Nung
YN
D000818:Animals; D030801:Animals, Genetically Modified; D003712:Dendrites / Q000502:physiology*; D004330:Drosophila / Q000502:physiology*; D004817:Epidermis / Q000294:innervation*; D049452:Green Fluorescent Proteins; D008164:Luminescent Proteins; D009475:Neurons, Afferent / Q000502:physiology*; D013194:Staining and Labeling
D008164:Luminescent Proteins; D049452:Green Fluorescent Proteins