Evidence for Cyclooxygenase‐1 Association with Caveolin‐1 and ‐2 in Cultured Human Embryonic Kidney (HEK 293) Cells

AbstractThe purpose of this study was to confirm protein‐protein interaction between cyclooxygenase‐1 (COX‐1) and caveolins. The interaction of cyclooxygenase‐1 and caveolins in the cultured human embryonic kidney (HEK 293) cells was investigated using immuno‐precipitation and Western blot analysis. In HEK 293 cells, high levels of caveolin‐2 and low level of caveolin‐1 at mRNA and protein level were observed without any detectable expression of caveolin‐3. Caveolae rich membranous fractions from the HEK 293 cells contained both COX‐1 and caveolin‐1 or caveolin‐2 in same fractions. The experiments of immuno‐precipitation showed complex formation between the COX‐1 and caveolin‐1 or caveolin‐2 in the HEK 293 cells. Confocal microscopic results also support co‐localization of COX‐1 and caveolin‐1 or caveolin‐2 at the plasma membrane. Co‐localization of caveolins with cylooxygenase‐1 in caveolae suggested that caveolin would play an important role in regulating the function of COX‐1. IUBMB Life, 56: 221‐227, 2004