Caspase-3 activation decreases lipid order in the outer plasma membrane leaflet during apoptosis: A fluorescent probe study.

Fiche publication

Date publication

août 2017

Journal

Biochimica et biophysica acta

Auteurs

Membres identifiés du Cancéropôle Est :
Pr MELY Yves

Tous les auteurs :
Pyrshev KA, Yesylevskyy SO, Mely Y, Demchenko AP, Klymchenko AS

Lien Pubmed

https://www.ncbi.nlm.nih.gov/pubmed/28784460

Résumé

In this research we investigate the connection between the cytoplasmic machinery of apoptosis and the plasma membrane organization by studying the coupling of caspase-3 activation and inhibition with PS exposure and the change of lipid order in plasma membrane sensed by a fluorescent membrane probe NR12S. First, we performed in silico molecular dynamics simulations, which suggest that the mechanism of response of NR12S to lipid order may combine both sensitivity to membrane polarity/hydration and change in the fluorophore orientation. Second, cellular studies revealed that upon triggering apoptosis with IPA-3 and camptothecin the NR12S response is similar to that observed after decrease of lipid order induced by cholesterol depletion, 7-ketocholesterol enrichment or sphingomyelin hydrolysis. NR12S response can be influenced by a caspase-3 inhibitor Z-DEVD-FMK. Flow cytometry data further indicate that the NR12S response correlates with the response of FITC-labeled DEVD-FMK peptide and GFP-labeled Annexin V on the whole time scale (0-24h) of apoptosis induction by camptothecin. We conclude that fine changes in lipid order observed by NR12S are coupled with early steps of cellular events in apoptosis.