Boiled and unboiled RT-4 whole cell and membrane extracts (30 μg) were separated by 10% SDS-PAGE, and the membrane was blotted with GPR81 antibody [HL4128] (GTX642574) diluted at 1:5000. The HRP-conjugated anti-rabbit IgG antibody (GTX213110-01) was used to detect the primary antibody. (WCE: whole cell extract; ME: membrane extract)