- In G protein-coupled receptors (GPCRs), the N-terminal domain is typically extracellular, while the C-terminal domain is intracellular.
- The N-terminal domain of a GPCR contains the extracellular loops, which are involved in ligand binding and selectivity. This region is located on the outer surface of the cell membrane and interacts with the extracellular environment.
- The C-terminal domain of a GPCR, on the other hand, contains the intracellular loops and the C-terminal tail. This region is located on the inner surface of the cell membrane and interacts with intracellular signaling proteins such as G proteins and arrestins. It is important to note that the exact location of the N- and C-terminal domains can vary depending on the specific GPCR and its conformational state. In some cases, portions of the N-terminal domain may be buried within the cell membrane, and portions of the C-terminal domain may be exposed to the extracellular environment. However, the overall orientation of the N- and C-terminal domains remains the same in most GPCRs.