Postsynaptic mad signaling at the Drosophila neuromuscular junction Journal Article

Author(s): Dudu, Veronika; Bittig, Thomas; Entchev, Eugeni V; Kicheva, Anna; Julicher, Frank; González-Gaitán, Marcos A
Article Title: Postsynaptic mad signaling at the Drosophila neuromuscular junction
Abstract: Background: Cell-to-cell communication at the synapse involves synaptic transmission as well as signaling mediated by growth factors, which provide developmental and plasticity cues. There is evidence that a retrograde, presynaptic transforming growth factor-β (TGF-β) signaling event regulates synapse development and function in Drosophila. Results: Here we show that a postsynaptic TGF-β signaling event occurs during larval development. The type I receptor Thick veins (Tkv) and the R-Smad transcription factor Mothers-against-dpp (Mad) are localized postsynaptically in the muscle. Furthermore, Mad phosphorylation occurs in regions facing the presynaptic active zones of neurotransmitter release within the postsynaptic subsynaptic reticulum (SSR). In order to monitor in real time the levels of TGF-β signaling in the synapse during synaptic transmission, we have established a FRAP assay to measure Mad nuclear import/export in the muscle. We show that Mad nuclear trafficking depends on stimulation of the muscle. Conclusions: Our data suggest a mechanism linking synaptic transmission and postsynaptic TGF-β signaling that may coordinate nerve-muscle development and function.
Journal Title: Current Biology
Volume: 16
Issue 7
ISSN: 0960-9822
Publisher: Cell Press  
Date Published: 2006-04-04
Start Page: 625
End Page: 635
Sponsor: This work was supported by the Max Planck Society, HFSP, and Deutsche Forschungsgemeinschaft.
DOI: 10.1016/j.cub.2006.02.061
Open access: no