Attenuation of the production of inositol 1,4,5-trisphosphate in the mouse vomeronasal organ by antibodies against the alphaq/11 subfamily of G-proteins.
The social and reproductive behaviors of most mammals are modulated by pheromones, which are perceived by the vomeronasal organ (VNO). Vomeronasal transduction in vertebrates is activated through G-protein-coupled receptors, which in turn leads to the generation of inositol 1,4,5-trisphosphate (IP(3)) and diacylglycerol (DAG) by the activity of phospholipase C. DAG has been shown to gate the transient receptor potential channel 2, whereas IP(3) may play a role in stimulating the release of calcium from the endoplasmic reticulum store. To investigate the role of the alpha subunits of G(q/11) in the transduction process, microvillar membranes from female mice VNO were preincubated with a selective C-terminal peptide antibody against Galpha(q/11) and then stimulated with adult male urine. Incubation of VNO membranes with antibodies against Galpha(q/11) blocked the production of IP(3) in a dose-dependent manner. We were also able to impair the production of IP(3) when we stimulated with 2-heptanone or 2,5-dimethylpyrazine in the presence of antibodies against the alpha subunit of G(q/11). 2-Heptanone is a known pheromone that has been linked to VIR receptors. Thus, our observations indicate that the alpha subunits of G(q/11) play a role in pheromonal signaling in the VNO.
Thompson
Roger N
RN
Department of Biological Sciences, Alabama State University, Montgomery, 36101-0271, USA.
Napier
Audrey
A
Wekesa
Kennedy S
KS
D000804:Angiotensin II / Q000037:antagonists & inhibitors / Q000494:pharmacology; D000818:Animals; D000906:Antibodies / Q000494:pharmacology*; D002462:Cell Membrane / Q000737:chemistry / Q000187:drug effects / Q000378:metabolism; D004075:Diglycerides / Q000096:biosynthesis; D004305:Dose-Response Relationship, Drug; D004789:Enzyme Activation; D005260:Female; D043802:GTP-Binding Protein alpha Subunits, Gq-G11 / Q000037:antagonists & inhibitors* / Q000378:metabolism; D015544:Inositol 1,4,5-Trisphosphate / Q000096:biosynthesis / Q000378:metabolism*; D007659:Ketones / Q000494:pharmacology; D008297:Male; D051379:Mice; D010455:Peptides / Q000737:chemistry / Q000494:pharmacology; D011719:Pyrazines / Q000494:pharmacology; D010738:Type C Phospholipases / Q000378:metabolism; D019147:Vomeronasal Organ / Q000737:chemistry / Q000187:drug effects / Q000378:metabolism*
D000906:Antibodies; D004075:Diglycerides; D007659:Ketones; D010455:Peptides; D011719:Pyrazines; D000804:Angiotensin II; D015544:Inositol 1,4,5-Trisphosphate; C011917:2-heptanone; D010738:Type C Phospholipases; D043802:GTP-Binding Protein alpha Subunits, Gq-G11; C075524:2,5-dimethylpyrazine