Format

Send to

Choose Destination
Sci Rep. 2017 Aug 31;7(1):10260. doi: 10.1038/s41598-017-09638-8.

Type 3 inositol 1,4,5-trisphosphate receptor is dispensable for sensory activation of the mammalian vomeronasal organ.

Author information

1
Center for Integrative Physiology and Molecular Medicine, Saarland University, 66421, Homburg, Germany.
2
Laboratoire de Physiologie de la Reproduction et des Comportements, UMR 0085 INRA-CNRS-IFCE-Université de Tours, Nouzilly, 37380, France.
3
Instituto de Biología y Genética Molecular (IBGM), University of Valladolid and CSIC, 47003, Valladolid, Spain.
4
Laboratory for Developmental Neurobiology, RIKEN Brain Science Institute, Saitama, 351-0198, Japan.
5
Center for Integrative Physiology and Molecular Medicine, Saarland University, 66421, Homburg, Germany. frank.zufall@uks.eu.

Abstract

Signal transduction in sensory neurons of the mammalian vomeronasal organ (VNO) involves the opening of the canonical transient receptor potential channel Trpc2, a Ca2+-permeable cation channel that is activated by diacylglycerol and inhibited by Ca2+-calmodulin. There has been a long-standing debate about the extent to which the second messenger inositol 1,4,5-trisphosphate (InsP3) and type 3 InsP3 receptor (InsP3R3) are involved in the opening of Trpc2 channels and in sensory activation of the VNO. To address this question, we investigated VNO function of mice carrying a knockout mutation in the Itpr3 locus causing a loss of InsP3R3. We established a new method to monitor Ca2+ in the endoplasmic reticulum of vomeronasal sensory neurons (VSNs) by employing the GFP-aequorin protein sensor erGAP2. We also performed simultaneous InsP3 photorelease and Ca2+ monitoring experiments, and analysed Ca2+ dynamics, sensory currents, and action potential or field potential responses in InsP3R3-deficient VSNs. Disruption of Itpr3 abolished or minimized the Ca2+ transients evoked by photoactivated InsP3, but there was virtually no effect on sensory activation of VSNs. Therefore, InsP3R3 is dispensable for primary chemoelectrical transduction in mouse VNO. We conclude that InsP3R3 is not required for gating of Trpc2 in VSNs.

Supplemental Content

Full text links

Icon for Nature Publishing Group Icon for PubMed Central
Loading ...
Support Center