Antibody Panel to Prostaglandin-Endoperoxidase Synthase Enymes (Cyclooxygenase, PGHS)

COX1 antibody, COX2 antibody, COX3 antibody

Prostaglandin-endoperoxide synthase (PTGS; fatty acid cyclooxygenase; PGH synthase) is the key enzyme in prostaglandin biosynthesis. The cyclooxygenase activity of the enzyme is inhibited by nonsteroidal antiinflammatory drugs such as aspirin and endomethacin.

Prostaglandin H2 synthase is known to pharmacologists as cyclooxygenase (COX), and its 2 isoforms are known as COX1 and COX2. Vane et al. (1994) outlined the actions of the 2 isoforms of COX. Stemming from this outline was a hypothesis that the therapeutic effects of drugs such as aspirin are due to inhibition of COX2, whereas the unwanted side-effects (and the action on platelets) result from inhibition of COX1.

PGHS is an integral membrane protein located primarily in the endoplasmic reticulum. It is bifunctional: the initial cyclooxygenase reaction, the target for NSAIDs, converts arachidonic acid to PGG2, while the subsequent peroxidase reaction converts PGG2 to PGH2. There are 2 isozymes of PGHS, PGHS1 and PGHS2, which differ in their regulation of expression and tissue distribution. Ovine PGHS1 is a 576-amino acid, glycosylated protein with an apparent subunit relative molecular mass of 70,000. PGHS1 is considered to be involved in cell-cell signaling and maintaining tissue homeostasis, whereas PGHS2 expression occurs in a limited number of cell types and is regulated by specific stimulatory events, leading to the hypothesis that PGHS2 is responsible for the prostanoid biosynthesis involved in inflammation and mitogenesis. Picot et al. (1994) determined the 3-dimensional structure of PGHS1 by x-ray crystallography. They concluded that the enzyme is in a monotopic arrangement with respect to the cell membrane, that is, it integrates into only a single leaflet of the lipid bilayer.

Chandrasekharan et al. (2002) described a third distinct COX isozyme, COX3, as well as 2 smaller COX1-derived proteins (partial COX1 or PCOX1 proteins). COX3 and 1 of the PCOX1 proteins (PCOX1A) are made from the COX1 gene but retain intron 1 in their mRNAs. PCOX1 proteins additionally contain an in-frame deletion of exons 5-8 of the COX1 mRNA. COX3 and PCOX mRNAs are expressed in canine cerebral cortex and in lesser amounts in other tissues analyzed. In humans, COX3 mRNA is expressed as a transcript of approximately 5.2 kb and is most abundant in cerebral cortex and heart. Intron 1 is conserved in length and in sequence in mammalian COX1 genes. This intron contains an open reading frame that introduces an insertion of 30 to 34 amino acids, depending on the mammalian species, into the hydrophobic signal peptide that directs COX1 into the lumen of the endoplasmic reticulum and nuclear envelope. COX3 and PCOX1A are expressed efficiently in insect cells as membrane-bound proteins. The signal peptide is not cleaved from either protein and both proteins are glycosylated. COX3, but not PCOX1A, possesses glycosylation-dependent cyclooxygenase activity. Comparison of canine COX3 activity with murine COX1 and COX2 demonstrated that this enzyme is selectively inhibited by analgesic/antipyretic drugs such as acetaminophen, phenacetin, antipyrine, and dipyrone, and is potently inhibited by some nonsteroidal antiinflammatory drugs. Thus, inhibition of COX3 could represent a primary central mechanism by which these drugs decrease pain and possibly fever.

Antibody Panel to Cyclooxygenase / PTGS / PDHS Enzymes (COX-1 antibodies, COX-2 antibodies, COX-3 antibodies).

Acris Antibodies offers a collection of polyclonal and monoclonal antibodies to the different Cyclooxygenase Enzymes (COX-1, COX-2, COX-3). These antibodies are usefull for detection of COX Enzymes using western blotting and immunohistochemistry methods, but also most other immunological applications.

Available antibodies to Cyclooxygenase Enzymes: COX1 antibody (COX-1), COX2 antibody (COX-2) and COX3 antibody (COX-3)

Protein