Mutagenesis and computer modeling studies of a GPCR conserved residue W5.43(194) in ligand recognition and signal transduction for CB2 receptor

► Tryptophan (W) residue is an important conserved residue among GPCRs. ► We explore the W5.43 in CB2 receptor and mutants for its roles by mutation and computer modeling. ► Our studies show that the W5.43 plays a key role in ligand binding and controlling the active states of the CB2 receptor.