Mechanotransduction and auditory transduction in Drosophila.
Insects are utterly reliant on sensory mechanotransduction, the process of converting physical stimuli into neuronal receptor potentials. The senses of proprioception, touch, and hearing are involved in almost every aspect of an adult insect's complex behavioral repertoire and are mediated by a diverse array of specialized sensilla and sensory neurons. The physiology and morphology of several of these have been described in detail; genetic approaches in Drosophila, combining behavioral screens and sensory electrophysiology with forward and reverse genetic techniques, have now revealed specific proteins involved in their differentiation and operation. These include three different TRP superfamily ion channels that are required for transduction in tactile bristles, chordotonal stretch receptors, and polymodal nociceptors. Transduction also depends on the normal differentiation and mechanical integrity of the modified cilia that form the neuronal sensory endings, the accessory structures that transmit stimuli to them and, in bristles, a specialized receptor lymph and transepithelial potential. Flies hear near-field sounds with a vibration-sensitive, antennal chordotonal organ. Biomechanical analyses of wild-type antennae reveal non-linear, active mechanical properties that increase their sensitivity to weak stimuli. The effects of mechanosensory and ciliary mutations on antennal mechanics show that the sensory cilia are the active motor elements and indicate distinct roles for TRPN and TRPV channels in auditory transduction and amplification.
Kernan
Maurice J
MJ
Department of Neurobiology and Behavior and Center for Developmental Genetics, Stony Brook University, Stony Brook, NY 11794-5230, USA. Maurice.Kernan@stonybrook.edu
D000222:Adaptation, Physiological / Q000235:genetics / Q000502:physiology; D000818:Animals; D019521:Body Patterning; D002454:Cell Differentiation / Q000235:genetics; D002923:Cilia / Q000235:genetics / Q000502:physiology*; D004330:Drosophila / Q000196:embryology / Q000235:genetics / Q000502:physiology; D029721:Drosophila Proteins / Q000235:genetics / Q000502:physiology; D005260:Female; D006309:Hearing / Q000235:genetics / Q000502:physiology*; D017136:Ion Transport / Q000502:physiology; D008297:Male; D040542:Mechanotransduction, Cellular / Q000235:genetics / Q000502:physiology*; D008954:Models, Biological; D016296:Mutagenesis; D009475:Neurons, Afferent / Q000502:physiology; D010146:Pain / Q000235:genetics / Q000378:metabolism; D012018:Reflex / Q000502:physiology; D012679:Sense Organs / Q000166:cytology / Q000196:embryology* / Q000294:innervation / Q000502:physiology*; D050052:TRPC Cation Channels / Q000502:physiology*; D014110:Touch / Q000502:physiology
D029721:Drosophila Proteins; D050052:TRPC Cation Channels