Open AccessDistinct Regulation of Transmitter Release at the Drosophila NMJ by Different Isoforms of nemy
Author(s) -
David Knight,
Konstantin G. Iliadi,
Natalia Iliadi,
Ronit Wilk,
Jiantao Hu,
Henry M. Krause,
Paul Taylor,
Michael F. Moran,
Gabrielle L. Boulianne
Publication year - 2015
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0132548
Subject(s) - neuromuscular junction , biology , gene isoform , microbiology and biotechnology , neurotransmission , synaptic plasticity , alternative splicing , neuroscience , biochemistry , gene , receptor
Synaptic transmission is highly plastic and subject to regulation by a wide variety of neuromodulators and neuropeptides. In the present study, we have examined the role of isoforms of the cytochrome b561 homologue called no extended memory ( nemy ) in regulation of synaptic strength and plasticity at the neuromuscular junction (NMJ) of third instar larvae in Drosophila . Specifically, we generated two independent excisions of nemy that differentially affect the expression of nemy isoforms. We show that the nemy 45 excision, which specifically reduces the expression of the longest splice form of nemy , leads to an increase in stimulus evoked transmitter release and altered synaptic plasticity at the NMJ. Conversely, the nemy 26.2 excision, which appears to reduce the expression of all splice forms except the longest splice isoform, shows a reduction in stimulus evoked transmitter release, and enhanced synaptic plasticity. We further show that nemy 45 mutants have reduced levels of amidated peptides similar to that observed in peptidyl-glycine hydryoxylating mono-oxygenase (PHM) mutants. In contrast, nemy 26.2 mutants show no defects in peptide amidation but rather display a decrease in Tyramine β hydroxylase activity (TβH). Taken together, these results show non-redundant roles for the different nemy isoforms and shed light on the complex regulation of neuromodulators.