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hamlet, a binary genetic switch between single- and multiple- dendrite neuron morphology.

Adrian W Moore·Lily Yeh Jan·Yuh Nung Jan
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Abstract

The dendritic morphology of neurons determines the number and type of inputs they receive. In the Drosophila peripheral nervous system (PNS), the external sensory (ES) neurons have a single nonbranched dendrite, whereas the lineally related multidendritic (MD) neurons have extensively branched dendritic arbors. We report that hamlet is a binary genetic switch between these contrasting morphological types. In hamlet mutants, ES neurons are converted to an MD fate, whereas ectopic hamlet expression in MD precursors results in transformation of MD neurons into ES neurons. Moreover, hamlet expression induced in MD neurons undergoing dendrite outgrowth drastically reduces arbor branching.

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Amino Acid SequenceAnimalsCell DifferentiationCell LineageClone CellsCloning, MolecularDNA-Binding ProteinsDendritesDrosophilaDrosophila ProteinsGene ExpressionGenetic Complementation TestMitosisMolecular Sequence DataMorphogenesisMutationNeuronsNeurons, AfferentNuclear ProteinsPeripheral Nervous SystemRNA, Double-StrandedSense OrgansTranscription FactorsJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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Adrian W Moore, Lily Yeh Jan, Yuh Nung Jan. 2002-08-23. hamlet, a binary genetic switch between single- and multiple- dendrite neuron morphology.. https://doi.org/10.1126/science.1072387

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