A green-fluorescent-protein-based assay for the characterization of G-protein-coupled receptors.

A simple and sensitive system to monitor activation and pharmacology of G-protein-coupled receptors in mammalian cells is described. It is based on cAMP-responsible-element-regulated expression of green fluorescent protein (GFP). Cotransfection with appropriate G-protein-coupled receptors and subsequent activation with agonists induces expression of GFP in a dose-dependent manner.

Tyramine and octopamine: antagonistic modulators of behavior and metabolism.

The phenolamines tyramine and octopamine are decarboxylation products of the amino acid tyrosine. Although tyramine is the biological precursor of octopamine, both compounds are independent neurotransmitters, acting through various G-protein coupled receptors. Especially, octopamine modulates a plethora of behaviors, peripheral and sense organs.

Putative histamine-gated chloride channel subunits of the insect visual system and thoracic ganglion.

Histamine-gated chloride channels, members of the ligand-gated ion channel superfamily, are thought to be peculiar for arthropods. Their cognate ligand, histamine, is the transmitter of all arthropod photoreceptors and of thoracic mechanoreceptors. To identify putative histamine-gated chloride channel subunits we scanned the Drosophila genome for putative ligand-gated chloride channel subunits and found 12 candidate genes.