For 10 points, identify this class of protein highly involved in signal transduction, named for its binding of guanine-containing compounds.
One of these proteins stimulates the development of membrane ruffles in fibroblasts, and their activity is blocked by arrestins. The conformational change occuring when rhodopsin is struck by a photon activates one protein of this type, known as transducin. Formation of the second messengers diacylglycerol and inositol triphosphate from PIP2 is catalyzed by (*) phospholipase C, an enzyme activated by the a-q subunit of these proteins. They may be classified as either heterotrimeric or small, like those in the Ras superfamily. These proteins are coupled to serpentine receptors, which have seven transmembrane domains and often activate adenylate cyclase, stimulating production of cyclic AMP. For 10 points, identify this class of protein highly involved in signal transduction, named for its binding of guanine-containing compounds.
One of these proteins stimulates the development of membrane ruffles in fibroblasts, and their activity is blocked by arrestins.
{G} proteins