Activity-dependent COX-2 proteolysis modulates aerobic respiration and proliferation in a prostaglandin-independent manner

Liat Hagit Hartal-Benishay, Sharon Tal, Amal Abd Elkader, Omar Ehsainieh, Ranin Srouji-Eid, Tali Lavy, Oded Kleifeld, Martin Mikl, Liza Barki-Harrington

Research output: Contribution to journalArticlepeer-review

Abstract

Cyclooxygenase-2 (COX-2) catalyzes the oxidation of arachidonic acid (AA) into a single product that is the source of all prostaglandins (PGs), ligands of multiple pro-inflammatory pathways. AA catalysis results in suicide inactivation, rendering the enzyme catalytically inactive. Here, we report that catalytic activity also leads to controlled cleavage of COX-2, an event that is differentially regulated by fatty acids, and blocked by COX inhibitors. We also find COX-2 fragments in human colon tumors. Using mass spectrometry, we identified two adjacent cleavage points within the catalytic domain, which give rise to COX-2 fragments that are catalytically inactive and localize to different cellular compartments. Expression of one of these fragments in cells significantly reduced mitochondrial function, increased lactate production, and enhanced proliferation. We propose that in addition to its role in generating PGs, COX-2 has PG-independent cellular functions that may account for its complex role in proliferative diseases and chronic inflammation.

Original languageAmerican English
Article number111403
JournaliScience
Volume27
Issue number12
DOIs
StatePublished - 20 Dec 2024

Keywords

  • Biomolecules
  • Molecular biology
  • Proteomics

All Science Journal Classification (ASJC) codes

  • General

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