Membrane regulation of 15LOX-1/PEBP1 complex prompts the generation of ferroptotic signals, oxygenated PEs

Free Radic Biol Med. 2023 Nov 1:208:458-467. doi: 10.1016/j.freeradbiomed.2023.09.001. Epub 2023 Sep 9.

Abstract

Ferroptosis is a regulated form of cell death, the mechanism of which is still to be understood. 15-lipoxygenase (15LOX) complex with phosphatidylethanolamine (PE)-binding protein 1 (PEBP1) catalyzes the generation of pro-ferroptotic cell death signals, hydroperoxy-polyunsaturated PE. We focused on gaining new insights into the molecular basis of these pro-ferroptotic interactions using computational modeling and liquid chromatography-mass spectrometry experiments. Simulations of 15LOX-1/PEBP1 complex dynamics and interactions with lipids revealed that association with the membrane triggers a conformational change in the complex. This conformational change facilitates the access of stearoyl/arachidonoyl-PE (SAPE) substrates to the catalytic site. Furthermore, the binding of SAPE promotes tight interactions within the complex and induces further conformational changes that facilitate the oxidation reaction. The reaction yields two hydroperoxides as products, 15-HpETE-PE and 12-HpETE-PE, at a ratio of 5:1. A significant effect of PEBP1 is observed only on the predominant product. Moreover, combined experiments and simulations consistently demonstrate the significance of PEBP1 P112E mutation in generating ferroptotic cell death signals.

Keywords: 15-Lipoxygenase; Ferroptosis; Lipid peroxidation; Membrane effect; PEBP1.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Arachidonate 15-Lipoxygenase* / metabolism
  • Arachidonate 15-Lipoxygenase* / physiology
  • Cell Death
  • Ferroptosis* / physiology
  • Humans
  • Oxidation-Reduction
  • Phosphatidylethanolamine Binding Protein* / metabolism
  • Phosphatidylethanolamine Binding Protein* / physiology
  • Phosphatidylethanolamines / chemistry
  • Phosphatidylethanolamines / metabolism
  • Swine

Substances

  • Arachidonate 15-Lipoxygenase
  • PEBP1 protein, human
  • Phosphatidylethanolamine Binding Protein
  • Phosphatidylethanolamines