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PMID: 9880574 Published · ppublish English Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S.

The Caenorhabditis elegans gene unc-25 encodes glutamic acid decarboxylase and is required for synaptic transmission but not synaptic development.

The Journal of neuroscience : the official journal of the Society for Neuroscience ·Vol. 19 ·No. 2 ·1999-01-15 ·Pages 539-48

Jin Y, Jorgensen E, Hartwieg E, Horvitz HR

Abstract

The neurotransmitter GABA has been proposed to play a role during nervous system development. We show that the Caenorhabditis elegans gene unc-25 encodes glutamic acid decarboxylase (GAD), the GABA biosynthetic enzyme. unc-25 is expressed specifically in GABAergic neurons. Null mutations in unc-25 eliminate the UNC-25 protein or alter amino acids conserved in all known GADs, result in a complete lack of GABA, and cause defects in all GABA-mediated behaviors. In unc-25 mutants the GABAergic neurons have normal axonal trajectories and synaptic connectivity, and the size and shape of synaptic vesicles are normal. The number of synaptic vesicles at GABAergic neuromuscular junctions is slightly increased. Cholinergic ventral nerve cord neurons, which innervate the same muscles as GABAergic ventral cord neurons, have normal morphology, connectivity, and synaptic vesicles. We conclude that GAD activity and GABA are not necessary for the development or maintenance of neuromuscular junctions in C. elegans.

MeSH Terms
Amino Acid Sequence Animals Axons/physiology,ultrastructure Caenorhabditis elegans/genetics,physiology Gene Expression Regulation, Enzymologic/physiology Glutamate Decarboxylase/genetics,metabolism Molecular Sequence Data Mutation Neuromuscular Junction/enzymology,physiology Phenotype Synapses/physiology Synaptic Transmission/genetics,physiology gamma-Aminobutyric Acid/physiology
Chemicals
gamma-Aminobutyric Acid Glutamate Decarboxylase
Authors & Affiliations
4 authors, click to expand affiliations / ORCID
Jin Y
Department of Biology, Sinsheimer Laboratories, University of California, Santa Cruz, California 95064, USA.
Jorgensen E
Hartwieg E
Horvitz H R
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Article Info
Journal
The Journal of neuroscience : the official journal of the Society for Neuroscience
Abbr.
J Neurosci
ISSN
0270-6474
Published
1999-01-15
Pages
539-48
Language
English
Region
United States
NLM ID
8102140
PMCID
PMC6782196
Subset
IM
Grants
NIGMS NIH HHS · GM24663 · United States
NINDS NIH HHS · NS34307 · United States
NINDS NIH HHS · NS35546 · United States
Databases
GENBANK
AF109378
External Links
PubMed source PMC Full Text View journal details
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