You have created a point mutant allele of your receptor that lacks the phosphorylation sites for theGPCR-regulated kinases, but you are concerned that it may not insert properly into the plasma membrane, with the N-terminus on the extracellular side and the C-terminus on the intracellular side. You have an S2 cell line that does not normally express this receptor. Describe an approach you could take to check whether the orientation of the receptor is appropriate.