Role of rhodopsin N-terminus in structure and function of rhodopsin-bitter taste receptor chimeras

► Molecular models of T2R4 built using rhodopsin crystal structure as template. ► Chimeric T2R4s with the rhodopsin N-terminal 33 and 38 amino acids characterized. ► Rho33-T2R4 chimera showed 2.5-fold increase in functional expression of T2R4. ► Rho33-T2R4 does not cause perturbations in T2R4 structure. ► Rho38-T2R4 causes extension of the transmembrane helix I in T2R4.