For 10 points, name these proteins that get their single-letter name because they bind guanosine nucleotides.
These proteins form a complex with a beta-2 adrenergic receptor that is a key target of anti-asthma drugs. The alpha subunits of these heterotrimeric proteins dissociate from the dimeric beta-gamma subunit to activate effector molecules like adenylyl cyclase. Their alpha subunits effectively hydrolyse a certain nucleoside triphosphate. Rhodopsin is in a family of receptors coupled to these proteins, which are often coupled to transmembrane receptors. For 10 points, name these proteins that get their single-letter name because they bind guanosine nucleotides.
These proteins form a complex with a beta-2 adrenergic receptor that is a key target of anti-asthma drugs.
G proteins [accept guanosine nucleotide-binding proteins before "guanosine"]