RRC ID 3520
Author Matthies DS, Fleming PA, Wilkes DM, Blakely RD.
Title The Caenorhabditis elegans choline transporter CHO-1 sustains acetylcholine synthesis and motor function in an activity-dependent manner.
Journal J Neurosci
Abstract Cholinergic neurotransmission supports motor, autonomic, and cognitive function and is compromised in myasthenias, cardiovascular diseases, and neurodegenerative disorders. Presynaptic uptake of choline via the sodium-dependent, hemicholinium-3-sensitive choline transporter (CHT) is believed to sustain acetylcholine (ACh) synthesis and release. Analysis of this hypothesis in vivo is limited in mammals because of the toxicity of CHT antagonists and the early postnatal lethality of CHT-/- mice (Ferguson et al., 2004). In Caenorhabditis elegans, in which cholinergic signaling supports motor activity and mutant alleles impacting ACh secretion and response can be propagated, we investigated the contribution of CHT (CHO-1) to facets of cholinergic neurobiology. Using the cho-1 promoter to drive expression of a translational, green fluorescent protein-CHO-1 fusion (CHO-1:GFP) in wild-type and kinesin (unc-104) mutant backgrounds, we establish in the living nematode that the transporter localizes to cholinergic synapses, and likely traffics on synaptic vesicles. Using embryonic primary cultures, we demonstrate that CHO-1 mediates hemicholinium-3-sensitive, high-affinity choline uptake that can be enhanced with depolarization in a Ca(2+)-dependent manner supporting ACh synthesis. Although homozygous cho-1 null mutants are viable, they possess 40% less ACh than wild-type animals and display stress-dependent defects in motor activity. In a choline-free liquid environment, cho-1 mutants demonstrate premature paralysis relative to wild-type animals. Our findings establish a requirement for presynaptic choline transport activity in vivo in a model amenable to a genetic dissection of CHO-1 regulation.
Volume 26(23)
Pages 6200-12
Published 2006-6-7
DOI 10.1523/JNEUROSCI.5036-05.2006
PII 26/23/6200
PMID 16763028
PMC PMC6675188
MeSH Acetylcholine / biosynthesis* Adaptation, Physiological Animals Animals, Genetically Modified Binding, Competitive Biological Transport / drug effects Caenorhabditis elegans / cytology Caenorhabditis elegans / embryology Caenorhabditis elegans / physiology Caenorhabditis elegans Proteins / metabolism Cells, Cultured Choline / pharmacokinetics Cholinergic Agents / pharmacology Electrophysiology Gene Deletion Green Fluorescent Proteins / genetics Hemicholinium 3 / pharmacology Membrane Transport Proteins / deficiency Membrane Transport Proteins / genetics Membrane Transport Proteins / physiology* Motor Activity / physiology* Nerve Tissue Proteins / metabolism Recombinant Fusion Proteins / metabolism Signal Transduction / physiology Synapses / metabolism* Tissue Distribution
IF 5.674
Times Cited 26
C.elegans tm373