Domain Formation and Stability in Complex Lipid Bilayers as Reported by Cholestatrienol

Jenny Isaksson, Thomas Nyholm, J Peter Slotte, Bodil Ramstedt

    Forskningsoutput: TidskriftsbidragArtikelVetenskapligPeer review

    78 Citeringar (Scopus)

    Sammanfattning

    In this study, we used cholestatrienol (CTL) as a fluorescent reporter molecule to study sterol-rich Lo domains in complex lipid bilayers. CTL is a fluorescent cholesterol analog that mimics the behavior of cholesterol well. The ability of 12SLPC to quench the fluorescence of cholestatrienol gives a measure of the amount of sterol included in Lo domains in mixed lipid membranes. The stability of sterol-rich domains formed in complex lipid mixtures containing saturated sphingomyelins, phosphatidylcholines, or galactosylceramide as potential domain-forming lipids were studied. The amount of sterol associated with sterol-rich domains seemed to always increase with increasing temperature. The quenching efficiency was highly dependent on the domain-forming lipid present in complex lipid mixtures. Sphingomyelins formed stable sterol-enriched domains and were able to shield CTL from quenching better than the other lipids included in this study. The saturated phosphatidylcholines also formed sterol-rich domains, but the quenching efficiency in membranes with these was higher than with sphingomyelins and the domains melted at lower temperatures. PGalCer was not able to form sterol-enriched domains. However, we found that PGalCer stabilized sterol-rich domains formed in PSM-containing bilayers. Using a fluorescent ceramide analog, we also demonstrated that N-palmitoyl-ceramide displaced the sterol from sphingolipid-rich domains in mixed bilayer membranes.

    OriginalspråkOdefinierat/okänt
    Sidor (från-till)4054–4063
    TidskriftBiophysical Journal
    Volym88
    Nummer6
    DOI
    StatusPublicerad - 2005
    MoE-publikationstypA1 Tidskriftsartikel-refererad

    Nyckelord

    • model membrane
    • cholesterol

    Citera det här