Patent ID: 8470561

Claim:
A fusion protein comprising, from N-terminus to C-terminus: a) a first portion of a G-protein coupled receptor (GPCR), wherein said first portion comprises the TM1, TM2 and TM3 regions of said GPCR; b) a stable, folded protein insertion , wherein said protein comprises a well-structured soluble domain which provides an amino and carboxyl termini that approximates the predicted distance between the cytoplasmic ends of TM3 and TM4 of said GPCR and which, when in crystalline form, aids in the formation of lattice contacts; c) a second portion of said GPCR, wherein said second portion comprises the TM4, TM5 TM6 and TM7 regions of said GPCR; and wherein said GPCR fusion protein is characterized in that it is crystallizable under lipid cubic phase or bicelle crystallization conditions.