G Protein-Coupled Receptors, GPCRs

G protein-coupled receptors (GPCRs) form a large group of evolutionarily related proteins that are cell surface receptors that detect molecules outside the cell and activate cellular responses. GPCRs are found only in eukaryotes, including yeast, and choanoflagellates. The ligands that bind and activate these receptors include light-sensitive compounds, odors, pheromones, hormones, and neurotransmitters. GPCRs are involved in many diseases such as mental, metabolic including endocrinological disorders, immunological including viral infections, cardiovascular, inflammatory, senses disorders, and cancer. Therefore, GPCRs are an important drug target and approximately 34% of all Food and Drug Administration (FDA) approved drugs target 108 members of this family.