The cyclic AMP (cAMP) receptor is a protein.
Cyclic AMP (cAMP) is a crucial second messenger in numerous biological processes. It doesn't act directly but rather binds to and activates cAMP-dependent protein kinases. This binding is facilitated by a specific receptor, which has been confirmed to be protein in nature. Research, including purification efforts, has solidified the protein nature of the cAMP receptor. These receptors are vital for mediating the diverse effects of cAMP signaling pathways.