title: Coordination and fine motor control depend on Drosophila TRPγ.
abstract: Motor coordination is broadly divided into gross and fine motor control, both of which depend on proprioceptive organs. However, the channels that function specifically in fine motor control are unknown. Here we show that mutations in trpγ disrupt fine motor control while leaving gross motor proficiency intact. The mutants are unable to coordinate precise leg movements during walking, and are ineffective in traversing large gaps due to an inability in making subtle postural adaptations that are requisite for this task. TRPγ is expressed in proprioceptive organs, and is required in both neurons and glia for gap crossing. We expressed TRPγ in vitro, and found that its activity is promoted by membrane stretch. A mutation eliminating the Na(+)/Ca(2+) exchanger suppresses the gap-crossing phenotype of trpγ flies. Our findings indicate that TRPγ contributes to fine motor control through mechanical activation in proprioceptive organs, thereby promoting Ca(2+) influx, which is required for function.
authors.affiliation: Department of Molecular, Cellular and Developmental Biology, Neuroscience Research Institute, University of California Santa Barbara, Santa Barbara, California 93106, USA.
authors.forename: Bradley
authors.initials: B
authors.lastname: Akitake
authors.affiliation: Department of Biological Chemistry, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA.
authors.forename: Qiuting
authors.initials: Q
authors.lastname: Ren
authors.affiliation: Department of Physiology, University of Texas Health Sciences Center, San Antonio, Texas 78229, USA.
authors.forename: Nina
authors.initials: N
authors.lastname: Boiko
authors.affiliation: 1] Department of Molecular, Cellular and Developmental Biology, Neuroscience Research Institute, University of California Santa Barbara, Santa Barbara, California 93106, USA [2] Department of Biological Chemistry, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA.
authors.forename: Jinfei
authors.initials: J
authors.lastname: Ni
authors.affiliation: Department of Molecular, Cellular and Developmental Biology, Neuroscience Research Institute, University of California Santa Barbara, Santa Barbara, California 93106, USA.
authors.forename: Takaaki
authors.initials: T
authors.lastname: Sokabe
authors.affiliation: Department of Physiology, University of Texas Health Sciences Center, San Antonio, Texas 78229, USA.
authors.forename: James D
authors.initials: JD
authors.lastname: Stockand
authors.affiliation: Department of Physiology, University of Texas Health Sciences Center, San Antonio, Texas 78229, USA.
authors.forename: Benjamin A
authors.initials: BA
authors.lastname: Eaton
authors.affiliation: Department of Molecular, Cellular and Developmental Biology, Neuroscience Research Institute, University of California Santa Barbara, Santa Barbara, California 93106, USA.
authors.forename: Craig
authors.initials: C
authors.lastname: Montell
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D002118:Calcium / Q000378:metabolism*; D029721:Drosophila Proteins / Q000235:genetics* / Q000378:metabolism / Q000502:physiology; D004331:Drosophila melanogaster; D055786:Gene Knockout Techniques; D057809:HEK293 Cells; D006801:Humans; D008465:Mechanoreceptors / Q000378:metabolism* / Q000502:physiology; D008854:Microscopy, Electron; D009048:Motor Skills / Q000502:physiology*; D018408:Patch-Clamp Techniques; D011434:Proprioception / Q000502:physiology*; D012964:Sodium / Q000378:metabolism*; D050051:Transient Receptor Potential Channels / Q000235:genetics* / Q000378:metabolism / Q000502:physiology
chemical_list: D029721:Drosophila Proteins; C411581:TRPgamma protein, Drosophila; D050051:Transient Receptor Potential Channels; D012964:Sodium; D002118:Calcium