Cho, Tiffany S, Beigaitė, Eglė, Klein, Nathaniel E et al. (2 more authors) (2022) The Putative Drosophila TMEM184B Ortholog Tmep Ensures Proper Locomotion by Restraining Ectopic Firing at the Neuromuscular Junction. Molecular neurobiology. pp. 2605-2619. ISSN 1559-1182
Abstract
TMEM184B is a putative seven-pass membrane protein that promotes axon degeneration after injury. TMEM184B mutation causes aberrant neuromuscular architecture and sensory and motor behavioral defects in mice. The mechanism through which TMEM184B causes neuromuscular defects is unknown. We employed Drosophila melanogaster to investigate the function of the closely related gene, Tmep (CG12004), at the neuromuscular junction. We show that Tmep is required for full adult viability and efficient larval locomotion. Tmep mutant larvae have a reduced body contraction rate compared to controls, with stronger deficits in females. In recordings from body wall muscles, Tmep mutants show substantial hyperexcitability, with many postsynaptic potentials fired in response to a single stimulation, consistent with a role for Tmep in restraining synaptic excitability. Additional branches and satellite boutons at Tmep mutant neuromuscular junctions are consistent with an activity-dependent synaptic overgrowth. Tmep is expressed in endosomes and synaptic vesicles within motor neurons, suggesting a possible role in synaptic membrane trafficking. Using RNAi knockdown, we show that Tmep is required in motor neurons for proper larval locomotion and excitability, and that its reduction increases levels of presynaptic calcium. Locomotor defects can be rescued by presynaptic knockdown of endoplasmic reticulum calcium channels or by reducing evoked release probability, further suggesting that excess synaptic activity drives behavioral deficiencies. Our work establishes a critical function for Tmep in the regulation of synaptic transmission and locomotor behavior.
Metadata
Item Type: | Article |
---|---|
Authors/Creators: |
|
Copyright, Publisher and Additional Information: | © The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2022. This is an author-produced version of the published paper. Uploaded in accordance with the publisher’s self-archiving policy. Further copying may not be permitted; contact the publisher for details |
Keywords: | Animals,Drosophila/metabolism,Drosophila Proteins/genetics,Drosophila melanogaster/metabolism,Larva/metabolism,Locomotion/genetics,Mice,Neuromuscular Junction/metabolism,Presynaptic Terminals/metabolism,Synaptic Transmission/physiology |
Dates: |
|
Institution: | The University of York |
Academic Units: | The University of York > Faculty of Sciences (York) > Biology (York) |
Depositing User: | Pure (York) |
Date Deposited: | 14 Jul 2022 15:50 |
Last Modified: | 21 Jan 2025 18:03 |
Published Version: | https://doi.org/10.1007/s12035-022-02760-3 |
Status: | Published |
Refereed: | Yes |
Identification Number: | 10.1007/s12035-022-02760-3 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:189098 |
Download
Filename: Fly_Tmep_manuscript_FINAL_ForPMC.docx
Description: Fly Tmep manuscript_FINAL_ForPMC