title: The bHLH-PAS protein Spineless is necessary for the diversification of dendrite morphology of Drosophila dendritic arborization neurons.
abstract: Dendrites exhibit a wide range of morphological diversity, and their arborization patterns are critical determinants of proper neural connectivity. How different neurons acquire their distinct dendritic branching patterns during development is not well understood. Here we report that Spineless (Ss), the Drosophila homolog of the mammalian aryl hydrocarbon (dioxin) receptor (Ahr), regulates dendrite diversity in the dendritic arborization (da) sensory neurons. In loss-of-function ss mutants, class I and II da neurons, which are normally characterized by their simple dendrite morphologies, elaborate more complex arbors, whereas the normally complex class III and IV da neurons develop simpler dendritic arbors. Consequently, different classes of da neurons elaborate dendrites with similar morphologies. In its control of dendritic diversity among da neurons, ss likely acts independently of its known cofactor tango and through a regulatory program distinct from those involving cut and abrupt. These findings suggest that one evolutionarily conserved role for Ahr in neuronal development concerns the diversification of dendrite morphology.
authors.affiliation: Howard Hughes Medical Institute, Department of Physiology, University of California at San Francisco, San Francisco, California 94143, USA.
authors.forename: Michael D
authors.initials: MD
authors.lastname: Kim
authors.forename: Lily Yeh
authors.initials: LY
authors.lastname: Jan
authors.forename: Yuh Nung
authors.initials: YN
authors.lastname: Jan
mesh_terms: D000818:Animals; D051792:Basic Helix-Loop-Helix Proteins / Q000737:chemistry; D002454:Cell Differentiation; D003712:Dendrites / Q000378:metabolism / Q000502:physiology*; D004147:Dioxins / Q000378:metabolism; D029721:Drosophila Proteins / Q000235:genetics*; D004331:Drosophila melanogaster; D018507:Gene Expression Regulation, Developmental; D006720:Homozygote; D009154:Mutation; D009474:Neurons / Q000378:metabolism* / Q000473:pathology*; D010641:Phenotype; D018336:Receptors, Aryl Hydrocarbon / Q000096:biosynthesis* / Q000235:genetics / Q000378:metabolism
chemical_list: D051792:Basic Helix-Loop-Helix Proteins; D004147:Dioxins; D029721:Drosophila Proteins; D018336:Receptors, Aryl Hydrocarbon; C112211:ss protein, Drosophila