Invitrogen™ MLNR Polyclonal Antibody

Motilin is a widely conserved 22 amino acid peptide hormone secreted from enterochromaffin cells of the gastrointestinal tract. Within the intestines, motilin potentiates intestinal motility by inducing contractions of the duodenum and through binding to surface receptors, designated GPR38 (G-protein coupled receptor 38). These motilin receptors are predominantly expressed in stomach, thyroid and bone marrow, and they are related to other G-protein coupled receptors located in the pituitary and hypothalamus, which mediate the signaling for growth hormone secretagogues. The gene encoding GPR38 is alternately spliced at the carboxy terminus to generate two related proteins that are designated GPR38-A and GPR38-B. Sequence comparisons of the two isoforms indicate that GPR38-A contains seven transmembrane domains while GPR38-B is predicted to contains only five transmembrane regions. Consistent with other G-protein coupled receptors, GPR38 activates phospholipase C signal transduction pathways and induces intracellular calcium mobilization after binding of motilin.