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Neurexin and neuroligin mediate retrograde synaptic inhibition in C. elegans.

ABSTRACT: The synaptic adhesion molecules neurexin and neuroligin alter the development and function of synapses and are linked to autism in humans. Here, we found that Caenorhabditis elegans neurexin (NRX-1) and neuroligin (NLG-1) mediated a retrograde synaptic signal that inhibited neurotransmitter release at neuromuscular junctions. Retrograde signaling was induced in mutants lacking a muscle microRNA (miR-1) and was blocked in mutants lacking NLG-1 or NRX-1. Release was rapid and abbreviated when the retrograde signal was on, whereas release was slow and prolonged when retrograde signaling was blocked. The retrograde signal adjusted release kinetics by inhibiting exocytosis of synaptic vesicles (SVs) that are distal to the site of calcium entry. Inhibition of release was mediated by increased presynaptic levels of tomosyn, an inhibitor of SV fusion.

SUBMITTER: Hu Z

PROVIDER: S-EPMC3791080 | biostudies-literature | 2012 Aug

REPOSITORIES: biostudies-literature

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Neurexin and neuroligin mediate retrograde synaptic inhibition in C. elegans.

Hu Zhitao Z Hom Sabrina S Kudze Tambudzai T Tong Xia-Jing XJ Choi Seungwon S Aramuni Gayane G Zhang Weiqi W Kaplan Joshua M JM

Science (New York, N.Y.) 20120802 6097

The synaptic adhesion molecules neurexin and neuroligin alter the development and function of synapses and are linked to autism in humans. Here, we found that Caenorhabditis elegans neurexin (NRX-1) and neuroligin (NLG-1) mediated a retrograde synaptic signal that inhibited neurotransmitter release at neuromuscular junctions. Retrograde signaling was induced in mutants lacking a muscle microRNA (miR-1) and was blocked in mutants lacking NLG-1 or NRX-1. Release was rapid and abbreviated when the ...[more]

PMID: 22859820

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