Functional characterisation of the Drosophila 5‐HTdro1 and 5‐HTdro2B serotonin receptors in insect cells: activation of a Gαs‐like protein by 5‐HTdro1 but lack of coupling to inhibitory G‐proteins by 5‐HTdro2B

Abstract
Insect cells are routinely used for the production of receptor proteins. Expression of the Drosophila 5‐HT dro1 serotonin receptor resulted in positive coupling of the receptor to adenylyl cyclase via the Gαs G‐protein subtype. The Drosophila 5‐HT dro2B receptor stimulated the metabolism of inositol phospholipid via a pertussis toxin‐insensitive G‐protein, but exhibited no detectable inhibition of adenylyl cyclase. Immunoblot analysis of the endogenous G‐proteins revealed that Sf9 cells lack the G‐protein subtypes Gαi1–3 and Gα0, but express the subtypes Gαs and Gαq .