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HLB-1 functions as a new regulator for the organization and function of neuromuscular junctions in nematode Caenorhabditis elegans.

ABSTRACT: To study the role of HLB-1 in regulating the organization and function of neuromuscular junctions in nematode Caenorhabditis elegans.To evaluate the functions of HLB-1 in regulating the organization and function of neuromuscular junctions, effects of hlb-1 mutation on the synaptic structures were revealed by uncovering the expression patterns of SNB-1::GFP and UNC-49::GFP, and pharmacologic assays with aldicarb and levamisole were also used to test the synaptic functions. Further rescue and mosaic analysis confirmed HLB-1's role in regulating the organization and function of neuromuscular junctions.Loss of HLB-1 function did not result in defects in neuronal outgrowth or neuronal loss, but caused obvious defects of SNB-1::GFP and UNC-49::GFP puncta localization, suggesting the altered presynaptic and postsynaptic structures. The mutant animals exhibited severe defects in locomotion behaviors and altered responses to an inhibitor of acetylcholinesterase and a cholinergic agonist, indicating the altered presynaptic and postsynaptic functions. Rescue and mosaic analysis experiments suggested that HLB-1 regulated synaptic functions in a cell nonautonomously way. Moreover, HLB-1 expression was not required for the presynaptic active zone morphology. Genetic evidence further demonstrated that hlb-1 acted in a parallel pathway with syd-2 to regulate the synaptic functions.HLB-1 appeared as a new regulator for the organization and function of neuromuscular junctions in C. elegans.

SUBMITTER: Wang DY

PROVIDER: S-EPMC5552579 | biostudies-other | 2009 Apr

REPOSITORIES: biostudies-other

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