Extracellular molecular targets are mainly Gprotein-coupledbody, GPCR. The GPCR family is the largest receptor family, with approximately 800 to 1000 confirmed family members. GPCR plays an extremely important role in the development of modern drugs, with about 50% of modern drugs targeted by GPCR.
The common feature of these GPCRs is that they all have seven transmembrane domains. GPCR signals are generally interacting with these GPCRs through extracellular ligands, causing conformational changes in GPCR, and regulating various signal passages downstream of GPCR by activating the triamcinal G protein.
Some receptors in the GPCR family are abnormally expressed in specific tissue cells, regulating the normal or abnormal physiological function of the human body, and are potential objects of drug development. Some GPCR ligands are small molecule peptides, and the modification and modification of these peptides has become one of the most important directions for the development of peptide drugs.