G Protein Coupled Receptor 26 (GPR26)

In the region of overlap, the deduced human and rat GPR26 proteins share greater than 95% amino acid sequence identity. The rat Gpr26 protein shares 25% sequence identity with both the serotonin receptor 5-HT5A (HTR5A) and the gastrin-releasing hormone receptor BB2. Gpr26 contains 7 predicted transmembrane domains, a short N terminus lacking the potential N-linked glycosylation site typical of other GPRs, and a pair of cationic residues corresponding to cationic residues conserved in purinergic P2Y receptors. Expression of recombinant rat Gpr26 in a human embryonic kidney cell line (HEK293) and a rat hepatoma cell line, but not in a human astrocytoma cell line, resulted in high basal cAMP levels, a slow growth rate, and derangements of normal cell shape.