Abstract.
The bioluminescent Ca2+-sensitive reporter protein, aequorin, was employed to develop an insect cell-based functional assay system for monitoring receptor-mediated changes of intracellular Ca2 +-concentrations. Drosophila Schneider 2 (S2) cells were genetically engineered to stably express both apoaequorin and the insect tachykinin-related peptide receptor, STKR. Lom-TK III, an STKR agonist, was shown to elicit concentration-dependent bioluminescent responses in these S2-STKR-Aeq cells. The EC50 value for the calcium effect detected by means of aequorin appeared to be nearly identical to the one that was measured by means of Fura-2, a fluorescent Ca2 +-indicator. In addition, this aequorin-based method was also utilised to study receptor antagonists. Experimental analysis of the effects exerted by spantide I, II and III, three potent substance P antagonists, on Lom-TK III-stimulated S2-STKR-Aeq cells showed that these compounds antagonise STKR-mediated responses in a concentration-dependent manner. The rank order of inhibitory potencies was spantide III > spantide II > spantide I.
Similar content being viewed by others
Author information
Authors and Affiliations
Additional information
Revised version received: 12 September 2001
Electronic Publication
Rights and permissions
About this article
Cite this article
Torfs, H., Poels, J., Detheux, M. et al. Recombinant aequorin as a reporter for receptor-mediated changes of intracellular Ca2+-levels in Drosophila S2 cells. Invert Neurosci 4, 119–124 (2002). https://doi.org/10.1007/s10158-001-0013-2
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/s10158-001-0013-2