Skip to main content
eScholarship
Open Access Publications from the University of California

UC Irvine

UC Irvine Previously Published Works bannerUC Irvine

Cav2-type calcium channels encoded by cac regulate AP-independent neurotransmitter release at cholinergic synapses in adult Drosophila brain.

  • Author(s): Gu, Huaiyu
  • Jiang, Shaojuan Amy
  • Campusano, Jorge M
  • Iniguez, Jorge
  • Su, Hailing
  • Hoang, Andy An
  • Lavian, Monica
  • Sun, Xicui
  • O'Dowd, Diane K
  • et al.
Creative Commons 'BY' version 4.0 license
Abstract

Voltage-gated calcium channels containing alpha1 subunits encoded by Ca(v)2 family genes are critical in regulating release of neurotransmitter at chemical synapses. In Drosophila, cac is the only Ca(v)2-type gene. Cacophony (CAC) channels are localized in motor neuron terminals where they have been shown to mediate evoked, but not AP-independent, release of glutamate at the larval neuromuscular junction (NMJ). Cultured embryonic neurons also express CAC channels, but there is no information about the properties of CAC-mediated currents in adult brain nor how these channels regulate transmission in central neural circuits where fast excitatory synaptic transmission is predominantly cholinergic. Here we report that wild-type neurons cultured from late stage pupal brains and antennal lobe projection neurons (PNs) examined in adult brains, express calcium currents with two components: a slow-inactivating current sensitive to the spider toxin Plectreurys toxin II (PLTXII) and a fast-inactivating PLTXII-resistant component. CAC channels are the major contributors to the slow-inactivating PLTXII-sensitive current based on selective reduction of this component in hypomorphic cac mutants (NT27 and TS3). Another characteristic of cac mutant neurons both in culture and in whole brain recordings is a reduced cholinergic miniature excitatory postsynaptic current frequency that is mimicked in wild-type neurons by acute application of PLTXII. These data demonstrate that cac encoded Ca(v)2-type calcium channels regulate action potential (AP)-independent release of neurotransmitter at excitatory cholinergic synapses in the adult brain, a function not predicted from studies at the larval NMJ.

Many UC-authored scholarly publications are freely available on this site because of the UC's open access policies. Let us know how this access is important for you.

Main Content
Current View