Hyperpolarization by activation of halorhodopsin results in enhanced synaptic transmission : Neuromuscular junction and CNS circuit

  • Optogenetics offers a unique method to regulate the activity of select neural circuits. However, the electrophysiological consequences of targeted optogenetic manipulation upon the entire circuit remain poorly understood. Analysis of the sensory-CNS-motor circuit in Drosophila larvae expressing eHpHR and ChR2-XXL revealed unexpected patterns of excitability. Optical stimulation of motor neurons targeted to express eNpHR resulted in inhibition followed by excitation of body wall contraction with repetitive stimulation in intact larvae. In situ preparations with direct electrophysiological measures showed an increased responsiveness to excitatory synaptic activity induced by sensory stimulation within a functional neural circuit. To ensure proper function of eNpHR and ChR2-XXL they were expressed in body wall muscle and direct electrophysiological measurements were obtained. Under eNpHR induced hyperpolarization the muscle remained excitable with increased amplitude of excitatory postsynaptic synaptic potentials. Theoretical models to explain the observations are presented. This study aids in increasing the understanding of the varied possible influences with light activated proteins within intact neural circuits.
Author:Matthew Mattingly, Kristin Weineck, Jennifer Costa, Robin L. Cooper
Pubmed Id:https://pubmed.ncbi.nlm.nih.gov/29969493
Parent Title (English):PLoS one
Place of publication:Lawrence, Kan.
Contributor(s):Brian D. McCabe
Document Type:Article
Year of Completion:2018
Date of first Publication:2018/07/03
Publishing Institution:Universitätsbibliothek Johann Christian Senckenberg
Release Date:2018/07/05
Tag:Larvae; Light pulses; Membrane potential; Motor neurons; Muscle electrophysiology; Muscle fibers; Nerve fibers; Neural pathways
Issue:(7): e0200107
Page Number:20
First Page:1
Last Page:20
Copyright: © 2018 Mattingly et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Institutes:Biochemie, Chemie und Pharmazie / Biochemie und Chemie
Dewey Decimal Classification:5 Naturwissenschaften und Mathematik / 57 Biowissenschaften; Biologie / 570 Biowissenschaften; Biologie
Sammlung Biologie / Sondersammelgebiets-Volltexte
Licence (German):License LogoCreative Commons - Namensnennung 4.0