PTGER4 (Prostaglandin E Receptor 4): PTGER4 is a gene that encodes a receptor for prostaglandin E2 (PGE2), a lipid mediator involved in inflammation and immune responses. PTGER4 plays a key role in regulating immune cell activation, cytokine production, and other cellular functions, influencing the body’s inflammatory processes. It has been studied in the context of autoimmune and inflammatory diseases.