Prostaglandin-endoperoxide synthase 2 (Cyclooxygenase 2) N-glycosylation machinery (COX-2 N-glycosylation machinery)

Cyclooxygenase 2 (COX-2), or Prostaglandin-endoperoxide synthase 2, is a pivotal enzyme that catalyzes the rate-limiting step in prostaglandin synthesis, playing a central role in inflammation and tumorigenesis (UniProt P35354). The functional maturation of COX-2 is uniquely dependent on N-glycosylation at three core sites (Asn53, Asn130, and Asn396), with a fourth site (Asn580) being glycosylated in approximately 50% of the molecules (Sevigny et al., 2006). The N-glycosylation machinery, specifically the oligosaccharyltransferase (OST) complex, is responsible for these modifications, which are essential for proper protein folding, stability, and catalytic activity (Mbonye et al., 2008). Research has demonstrated that inhibiting the glycosylation of COX-2 leads to its misfolding and subsequent degradation via the endoplasmic reticulum-associated degradation (ERAD) pathway, effectively reducing prostaglandin production (Conti et al., 2002). This machinery represents a novel therapeutic target, as disrupting COX-2 glycosylation can suppress its pro-inflammatory and pro-oncogenic effects in diseases like colorectal cancer and arthritis. However, because the N-glycosylation machinery is shared by many proteins, achieving specificity for COX-2 remains a significant therapeutic challenge (Lopez-Casas et al., 2014).

Other names

PTGS2 N-glycosylationCOX-2 glycosylation pathwayOligosaccharyltransferase-mediated COX-2 modification

Inhibition of N-linked glycosylation via the oligosaccharyltransferase (OST) complex or glycan precursor depletion, leading to COX-2 misfolding, ER-associated degradation (ERAD), and reduced prostaglandin synthesis.