title: C. elegans bicd-1, homolog of the Drosophila dynein accessory factor Bicaudal D, regulates the branching of PVD sensory neuron dendrites.
abstract: The establishment of cell type-specific dendritic arborization patterns is a key phase in the assembly of neuronal circuitry that facilitates the integration and processing of synaptic and sensory input. Although studies in Drosophila and vertebrate systems have identified a variety of factors that regulate dendrite branch formation, the molecular mechanisms that control this process remain poorly defined. Here, we introduce the use of the Caenorhabditis elegans PVD neurons, a pair of putative nociceptors that elaborate complex dendritic arbors, as a tractable model for conducting high-throughput RNAi screens aimed at identifying key regulators of dendritic branch formation. By carrying out two separate RNAi screens, a small-scale candidate-based screen and a large-scale screen of the ~3000 genes on chromosome IV, we retrieved 11 genes that either promote or suppress the formation of PVD-associated dendrites. We present a detailed functional characterization of one of the genes, bicd-1, which encodes a microtubule-associated protein previously shown to modulate the transport of mRNAs and organelles in a variety of organisms. Specifically, we describe a novel role for bicd-1 in regulating dendrite branch formation and show that bicd-1 is likely to be expressed, and primarily required, in PVD neurons to control dendritic branching. We also present evidence that bicd-1 operates in a conserved pathway with dhc-1 and unc-116, components of the dynein minus-end-directed and kinesin-1 plus-end-directed microtubule-based motor complexes, respectively, and interacts genetically with the repulsive guidance receptor unc-5.
authors.affiliation: Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY 10461, USA.
authors.forename: Cristina
authors.initials: C
authors.lastname: Aguirre-Chen
authors.forename: Hannes E
authors.initials: HE
authors.lastname: Bülow
authors.forename: Zaven
authors.initials: Z
authors.lastname: Kaprielian
mesh_terms: D000818:Animals; D017173:Caenorhabditis elegans / Q000166:cytology* / Q000235:genetics / Q000378:metabolism*; D029742:Caenorhabditis elegans Proteins / Q000235:genetics / Q000378:metabolism*; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism; D056445:Cytoplasmic Dyneins / Q000235:genetics / Q000378:metabolism; D003712:Dendrites / Q000378:metabolism*; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism*; D016547:Kinesins / Q000235:genetics / Q000378:metabolism; D011485:Protein Binding; D034622:RNA Interference; D011984:Sensory Receptor Cells / Q000166:cytology* / Q000378:metabolism*
chemical_list: C061998:BicD protein, Drosophila; D029742:Caenorhabditis elegans Proteins; D018797:Cell Cycle Proteins; D029721:Drosophila Proteins; C502663:UNC-116 protein, C elegans; D056445:Cytoplasmic Dyneins; C502824:DHC-1 protein, C elegans; D016547:Kinesins