Recombinant aequorin as a reporter for receptor-mediated changes of intracellular Ca2+ -levels in Drosophila S2 cells4412, Torfs, H., Poels J, Detheux M., Dupriez V., Van Loy T., Vercammen L., Vassart G., Parmentier M., and J. Broeck Vanden , Invert.Neurosci., 0/4/2002, Volume 4, Issue 3, Number 124, p.119 - 124, (2002)