RRC ID 45940
著者 Caylor RC, Jin Y, Ackley BD.
タイトル The Caenorhabditis elegans voltage-gated calcium channel subunits UNC-2 and UNC-36 and the calcium-dependent kinase UNC-43/CaMKII regulate neuromuscular junction morphology.
ジャーナル Neural Dev
Abstract BACKGROUND:The conserved Caenorhabditis elegans proteins NID-1/nidogen and PTP-3A/LAR-RPTP function to efficiently localize the presynaptic scaffold protein SYD-2/α-liprin at active zones. Loss of function in these molecules results in defects in the size, morphology and spacing of neuromuscular junctions.
RESULTS:Here we show that the Cav2-like voltage-gated calcium channel (VGCC) proteins, UNC-2 and UNC-36, and the calmodulin kinase II (CaMKII), UNC-43, function to regulate the size and morphology of presynaptic domains in C. elegans. Loss of function in unc-2, unc-36 or unc-43 resulted in slightly larger GABAergic neuromuscular junctions (NMJs), but could suppress the synaptic morphology defects found in nid-1/nidogen or ptp-3/LAR mutants. A gain-of-function mutation in unc-43 caused defects similar to those found in nid-1 mutants. Mutations in egl-19, Cav1-like, or cca-1, Cav3-like, α1 subunits, or the second α2/δ subunit, tag-180, did not suppress nid-1, suggesting a specific interaction between unc-2 and the synaptic extracellular matrix (ECM) component nidogen. Using a synaptic vesicle marker in time-lapse microscopy studies, we observed GABAergic motor neurons adding NMJ-like structures during late larval development. The synaptic bouton addition appeared to form in at least two ways: (1) de novo formation, where a cluster of vesicles appeared to coalesce, or (2) when a single punctum became enlarged and then divided to form two discrete fluorescent puncta. In comparison to wild type animals, we found unc-2 mutants exhibited reduced NMJ dynamics, with fewer observed divisions during a similar stage of development.
CONCLUSIONS:We identified UNC-2/UNC-36 VGCCs and UNC-43/CaMKII as regulators of C. elegans synaptogenesis. UNC-2 has a modest role in synapse formation, but a broader role in regulating dynamic changes in the size and morphology of synapses that occur during organismal development. During the late 4th larval stage (L4), wild type animals exhibit synaptic morphologies that are similar to those found in animals lacking NID-1/PTP-3 adhesion, as well as those with constitutive activation of UNC-43. Genetic evidence indicates that the VGCCs and the NID-1/PTP-3 adhesion complex provide opposing functions in synaptic development, suggesting that modulation of synaptic adhesion may underlie synapse development in C. elegans.
巻・号 8
ページ 10
公開日 2013-5-10
DOI 10.1186/1749-8104-8-10
PII 1749-8104-8-10
PMID 23663262
PMC PMC3661369
MeSH Animals Caenorhabditis elegans Caenorhabditis elegans Proteins / genetics Caenorhabditis elegans Proteins / metabolism* Calcium Channels / genetics Calcium Channels / metabolism* Calcium-Calmodulin-Dependent Protein Kinase Kinase / metabolism Calcium-Calmodulin-Dependent Protein Kinase Type 2 / metabolism* Calcium-Calmodulin-Dependent Protein Kinases / genetics Calcium-Calmodulin-Dependent Protein Kinases / metabolism Membrane Glycoproteins / genetics Membrane Proteins / metabolism* Mutation / genetics Neuromuscular Junction / cytology* Neuromuscular Junction / metabolism Synapses / metabolism Synapses / pathology* Synaptic Vesicles / metabolism
IF 2.63
引用数 8
WOS 分野 DEVELOPMENTAL BIOLOGY NEUROSCIENCES
リソース情報
線虫 tm352