Changes in membrane lipids drive increased endocytosis following Fas ligation

Mauro Degli Esposti, Paola Matarrese, Antonella Tinari, Agostina Longo, Serena Recalchi, Roya Khosravi-Far, Walter Malorni, Roberta Misasi, Tina Garofalo, Maurizio Sorice

Research output: Contribution to journalArticle

Abstract

Once activated, some surface receptors promote membrane movements that open new portals of endocytosis, in part to facilitate the internalization of their activated complexes. The prototypic death receptor Fas (CD95/Apo1) promotes a wave of enhanced endocytosis that induces a transient intermixing of endosomes with mitochondria in cells that require mitochondria to amplify death signaling. This initiates a global alteration in membrane traffic that originates from changes in key membrane lipids occurring in the endoplasmic reticulum (ER). We have focused the current study on specific lipid changes occurring early after Fas ligation. We analyzed the interaction between endosomes and mitochondria in Jurkat T cells by nanospray-Time-of-flight (ToF) Mass Spectrometry. Immediately after Fas ligation, we found a transient wave of lipid changes that drives a subpopulation of early endosomes to merge with mitochondria. The earliest event appears to be a decrease of phosphatidylcholine (PC), linked to a metabolic switch enhancing phosphatidylinositol (PI) and phosphoinositides, which are crucial for the formation of vacuolar membranes and endocytosis. Lipid changes occur independently of caspase activation and appear to be exacerbated by caspase inhibition. Conversely, inhibition or compensation of PC deficiency attenuates endocytosis, endosome-mitochondria mixing and the induction of cell death. Deficiency of receptor interacting protein, RIP, also limits the specific changes in membrane lipids that are induced by Fas activation, with parallel reduction of endocytosis. Thus, Fas activation rapidly changes the interconversion of PC and PI, which then drives enhanced endocytosis, thus likely propagating death signaling from the cell surface to mitochondria and other organelles.

Original languageEnglish
Pages (from-to)681-695
Number of pages15
JournalApoptosis
Volume22
Issue number5
DOIs
Publication statusPublished - May 1 2017

    Fingerprint

Keywords

  • Cell death
  • Endosomes
  • Membrane lipids
  • Membrane traffic
  • Mitochondria

ASJC Scopus subject areas

  • Pharmacology
  • Pharmaceutical Science
  • Clinical Biochemistry
  • Cell Biology
  • Biochemistry, medical
  • Cancer Research

Cite this

Degli Esposti, M., Matarrese, P., Tinari, A., Longo, A., Recalchi, S., Khosravi-Far, R., Malorni, W., Misasi, R., Garofalo, T., & Sorice, M. (2017). Changes in membrane lipids drive increased endocytosis following Fas ligation. Apoptosis, 22(5), 681-695. https://doi.org/10.1007/s10495-017-1362-6