title: Crossveinless-c, the Drosophila homolog of tumor suppressor DLC1, regulates directional elongation of dendritic branches via down-regulating Rho1 activity.
abstract: Diverse neuronal subtypes develop distinctive morphologies of dendritic arbors that receive synaptic or sensory inputs. Dendritic arbors of many subtypes take on a polarized shape, and one underlying mechanism is unidirectionally biased elongation of dendritic branches. As reported herein, we found that Drosophila Crossveinless-c (Cv-c) was a key regulator for such directional growth. In the cv-c mutant, two subclass of multidendritic sensory neurons examined formed dorsally directed branches; however, dendritic branches had difficulty in growing along the anterior-posterior (A-P) body axis. Cv-c belongs to the family of Rho GTPase-activating proteins (RhoGAPs) and is the homolog of human tumor suppressor DLC1. The RhoGAP activity of Cv-c was required cell-autonomously for the A-P-oriented growth, and Cv-c elevated the GTPase activity of Rho1 and Cdc42 in a cell-free assay. Our analysis of genetic interactions suggested that Rho1 was the target of Cv-c in vivo. All of our results suggest that Cv-c contributes to sprouting and subsequent growth of the A-P-oriented branches through negative regulation of Rho1. We discuss a role of Cv-c in dendritic growth in response to environmental cues.
authors.affiliation: Laboratory of Cell Recognition and Pattern Formation, Graduate School of Biostudies, South Campus Research Building (Building G), Kyoto University, Yoshida Konoe-cho, Sakyo-ku, Kyoto 606-8507, Japan.
authors.forename: Daichi
authors.initials: D
authors.lastname: Sato
authors.forename: Kaoru
authors.initials: K
authors.lastname: Sugimura
authors.forename: Daisuke
authors.initials: D
authors.lastname: Satoh
authors.forename: Tadashi
authors.initials: T
authors.lastname: Uemura
mesh_terms: D017398:Alternative Splicing; D000818:Animals; D019521:Body Patterning / Q000502:physiology; D003712:Dendrites / Q000378:metabolism* / Q000648:ultrastructure*; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism*; D004331:Drosophila melanogaster / Q000033:anatomy & histology / Q000502:physiology; D020690:GTPase-Activating Proteins / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D010641:Phenotype; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D025521:Tumor Suppressor Proteins / Q000235:genetics / Q000378:metabolism; D020744:rac GTP-Binding Proteins / Q000235:genetics / Q000378:metabolism; D020741:rho GTP-Binding Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: C112352:DLC1 protein, human; D029721:Drosophila Proteins; D020690:GTPase-Activating Proteins; C090146:Rac1 protein, Drosophila; D011993:Recombinant Fusion Proteins; D025521:Tumor Suppressor Proteins; C502709:cv-c protein, Drosophila; C511153:Rho1 protein, Drosophila; D020744:rac GTP-Binding Proteins; D020741:rho GTP-Binding Proteins