Urogenital distribution of a mouse membrane-associated prostaglandin E-2 synthase

PGE(2) plays a critical role in regulating renal function and facilitating reproduction. One of the rate-limiting biosynthetic enzymes in PGE(2) synth esis is the terminal PGE(2) synthase (PGES). In the present studies, we rep ort the functional expression of a membrane-associated murine PGES (mPGES) and its expression in urogenital tissues. Two independent cDNA clones shari ng an identical open reading frame of 459 bp and encoding a peptide of 153 amino acids, but differing in the 3'-untranslated region, were identified. Assays for enzymatic activity, using microsomes prepared from cells transfe cted with mPGES cDNA, showed that these cDNA sequences encode a functional protein that catalyzes the conversion of PGH(2) to PGE(2). Constitutive exp ression of mPGES was highest in the mouse kidney, ovary, and urinary bladde r but was also expressed at lower levels in uterus and testis. Renal mPGES expression was predominantly localized to epithelia of distal tubules and m edullary collecting ducts. High expression was also seen in transitional ep ithelial cells of bladder and ureter and in the primary and secondary folli cles in the ovary. In conclusion, mPGES is constitutively expressed along t he urogenital tract, where it may have important roles in normal physiology and disease.