Blockade of insect odorant receptor currents by amiloride derivatives.

@article{Pask2013BlockadeOI,
  title={Blockade of insect odorant receptor currents by amiloride derivatives.},
  author={Gregory M. Pask and Y. Bobkov and E. Corey and B. Ache and L. Zwiebel},
  journal={Chemical senses},
  year={2013},
  volume={38 3},
  pages={
          221-9
        }
}
Insect odorant receptors (ORs) function as heteromeric odorant-gated ion channels consisting of a conserved coreceptor, Orco, and an odorant-sensitive tuning subunit. Although some OR modulators have been identified, an extended library of pharmacological tools is currently lacking and would aid in furthering our understanding of insect OR complexes. We now demonstrate that amiloride and several derivatives, which have been extensively used as blockers for various ion channels and transporters… Expand
Positive Allosteric Modulation of Insect Olfactory Receptor Function by ORco Agonists
TLDR
The results suggest that insect heteromeric ORs are highly dynamic complexes adopting different conformations that change in a concerted fashion as a result of the interplay between the subunits of the oligomeric assemblies, and that allosteric modulation may constitute an important element in the modulation and fining tuning of olfactory reception function. Expand
The role of the coreceptor Orco in insect olfactory transduction
TLDR
In situ studies in hawkmoths falsify the hypothesis that Orco underlies odorant-induced ionotropic signal transduction in all insect species, and suggest Orco forms a metabotropically gated, slow cation channel which controls odorant response threshold and kinetics of the sensory neuron. Expand
No Evidence for Ionotropic Pheromone Transduction in the Hawkmoth Manduca sexta
TLDR
The results suggest no involvement for Orco in the primary transduction events, in contrast to amiloride-sensitive channels, and instead acts as a voltage- and apparently second messenger-gated pacemaker channel controlling the membrane potential and hence threshold and kinetics of the pheromone response. Expand
An inhibitor of Na(+)/Ca(2+) exchange blocks activation of insect olfactory receptors.
TLDR
K-R7943 represents a valuable tool to further investigate the functional properties of arthropod olfactory receptors and raises the interesting specter that activation of these ionotropic receptors is directly or indirectly linked to a Na(+)/Ca(2+) exchanger, thereby providing a template for drug design potentially allowing improved control of insect pests and disease vectors. Expand
Mutational Analysis of Cysteine Residues of the Insect Odorant Co-receptor (Orco) from Drosophila melanogaster Reveals Differential Effects on Agonist- and Odorant-tuning Receptor-dependent Activation*
TLDR
It is shown that intracellular loop 3 is important for Orco channel activation and suggests differences in the structural requirements for the activation of homomeric and heteromeric OrcoChannel complexes. Expand
Odorant receptor-mediated sperm activation in disease vector mosquitoes
TLDR
A subset of odorant receptors showing transcript expression in the testes of the malaria mosquito, Anopheles gambiae, is identified and functional evidence that the broadly conserved insect coreceptor, Orco, mediates flagellar activation in mosquito spermatozoa is provided. Expand
Insect Olfactory Receptors
TLDR
The roles of the three known families of insect olfactory receptors are described: odorant receptors (Ors), ionotropic receptors (Irs), and CO2-sensitive gustatory receptors (Grs). Expand
Inhibition of Anopheles gambiae Odorant Receptor Function by Mosquito Repellents*
TLDR
It is demonstrated that heteromeric OR (ORx/Orco) function was susceptible to strong inhibition by all tested mosquito repellents except DEET, and it was demonstrated that the observed inhibition was due to efficient blocking of Orco (olfactory receptor coreceptor) function. Expand
Olfactory signaling in insects.
  • D. Wicher
  • Biology, Medicine
  • Progress in molecular biology and translational science
  • 2015
TLDR
The cellular signaling events associated with detection of cognate ligands by the different types of odorant receptors are reviewed, including ionotropic as well as metabotropic mechanisms. Expand
In situ Tip-Recordings Found No Evidence for an Orco-Based Ionotropic Mechanism of Pheromone-Transduction in Manduca sexta
TLDR
It is concluded that there is no evidence for an Orco-dependent ionotropic pheromone transduction cascade in M. sexta Orco, which appears to be a slower, second messenger-dependent pacemaker channel which affects kinetics and threshold of phersomone-detection via changes of intracellular Ca2+ baseline concentrations. Expand
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The identification and characterization of an Orco family agonist, VUAA1, is reported, which represents a powerful new family of compounds that can be used to disrupt the destructive behaviors of nuisance insects, agricultural pests, and disease vectors alike. Expand
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TLDR
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TLDR
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TLDR
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