RESULTS

Expression of BFPP mutant receptors

GPR56 or GPR56R38W, GPR56Y88C, GPR56C91S, GPR56R565W, GPR56L640RBFPP mutants were expressed in HEK293 cells by transient transfection (Figure 1). It was previously reported that GPR56 is fully cleaved from the GPS in HEK293 cells [33]. Under the SDS PAGE conditions reported herein, the non-covalent interactions between NTF and CTF were lost and only the receptor NTF was detected with the expected size around 55kDa using anti-GPR56 antibody which recognizes the NTF of the receptor. A decrease in the expression for allBFPP mutant receptors was observed compared with thewild-type GPR56. All BFPP mutants used in this study were previously reported to be expressed on the cell surface [32].