Receptor for prostaglandin E2 (PGE2). The activity of this receptor is mediated by G(q) proteins which activate a phosphatidylinositol-calcium second messenger system. May play a role as an important modulator of renal function (By similarity). Implicated the smooth muscle contractile response to PGE2 in various tissues. Isoform 1 and isoform 2 have identical ligand binding properties, but isoform 2 lacks coupling to calcium mobilization and may therefore attenuate the action of PGE2 on tissues. Highly abundant in kidney and lung. Found in a lesser extent in spleen, colon, and thymus. Also expressed in uterine myometrium and endometrium. Phosphorylated. Belongs to the G-protein coupled receptor 1 family.