Human GPR87 gene is located on chromosome 3q24. GPR87 is composed of a start ATG within a Kozak consensus sequence, an open reading frame (ORF) of 1077 bp, and a putative poly (A) signal AATAAA 40 bp located downstream the stop codon.

Human GPR87 protein contains 358 AA arranged in a seven transmembrane (7TM) topology. It is comprised of an extracellular N terminus, seven helixes, three intracellular loops, three extracellular loops and an intracellular C terminus. The third intracellular loop and the C terminus might be important in G protein coupling. As a special feature, the C terminus of GPR87 bears consensus site S/T-X-V (T356, D357, V358) for binding of PDZ domain-containing proteins. LPA binding is suggested to involve residue 115 in TM3 and K296 in TM7.

Gene targeting strategy for B-hGPR87 mice. The exons 2~3 of mouse Gpr87 gene that encode the full-length protein were replaced by human GPR87 exons 2~3 in B-hGPR87 mice.

Strain specific analysis of GPR87 mRNA expression in wild-type C57BL/6 mice and B-hGPR87 mice by RT-PCR. Lung RNA were isolated from wildtype C57BL/6 mice (+/+) and homozygous B-hGPR87 mice (H/H), then cDNA libraries were synthesized by reverse transcription, followed by PCR with mouse or human GPR87 primers. Mouse Gpr87 mRNA was detectable only in wild-type C57BL/6 mice. Human GPR87 mRNA was detectable only in homozygous B-hGPR87 mice but not in wild-type mice.

Western blot analysis of GPR87 protein expression in homozygous B-hGPR87 mice. Various tissue lysates were collected from C57BL/6N wildtype mice (+/+) and homozygous B-hGPR87 mice (H/H), and then analyzed by western blot with anti-GPR87 antibody. 40 μg total proteins were loaded for western blotting analysis. GPR87 was detected in stomach, lung, esophagus and bladder.