Affordable Access

deepdyve-link
Publisher Website

Limited distal organelles and synaptic function in extensive monoaminergic innervation.

Authors
  • Tao, Juan1
  • Bulgari, Dinara1
  • Deitcher, David L2
  • Levitan, Edwin S3
  • 1 Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, PA 15261, USA.
  • 2 Department of Neurobiology and Behavior, Cornell University, Ithaca, NY 14853, USA.
  • 3 Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, PA 15261, USA [email protected]
Type
Published Article
Journal
Journal of Cell Science
Publisher
The Company of Biologists
Publication Date
Aug 01, 2017
Volume
130
Issue
15
Pages
2520–2529
Identifiers
DOI: 10.1242/jcs.201111
PMID: 28600320
Source
Medline
Keywords
License
Unknown

Abstract

Organelles such as neuropeptide-containing dense-core vesicles (DCVs) and mitochondria travel down axons to supply synaptic boutons. DCV distribution among en passant boutons in small axonal arbors is mediated by circulation with bidirectional capture. However, it is not known how organelles are distributed in extensive arbors associated with mammalian dopamine neuron vulnerability, and with volume transmission and neuromodulation by monoamines and neuropeptides. Therefore, we studied presynaptic organelle distribution in Drosophila octopamine neurons that innervate ∼20 muscles with ∼1500 boutons. Unlike in smaller arbors, distal boutons in these arbors contain fewer DCVs and mitochondria, although active zones are present. Absence of vesicle circulation is evident by proximal nascent DCV delivery, limited impact of retrograde transport and older distal DCVs. Traffic studies show that DCV axonal transport and synaptic capture are not scaled for extensive innervation, thus limiting distal delivery. Activity-induced synaptic endocytosis and synaptic neuropeptide release are also reduced distally. We propose that limits in organelle transport and synaptic capture compromise distal synapse maintenance and function in extensive axonal arbors, thereby affecting development, plasticity and vulnerability to neurodegenerative disease.

Report this publication

Statistics

Seen <100 times