Fig 8. A model for the effect of euphol on TGF-β receptor partitioning between lipid rafts/caveolae- and clathrin-mediated endocytosis.

In mammalian cells, there are 2 major TβR-I-TβR-II complexes (complex I and complex II) present on the cell surface. Complex I and complex II are mainly localized in the non-lipid raft and lipid raft/caveolae microdomains of the plasma membrane, respectively. Euphol increases the formation and/or stabilization of lipid rafts/caveolae by integration into the plasma membrane, thereby increasing the localization of TβR-I and TβR-II in lipid rafts/caveolae (as complex II), facilitating rapid degradation of TGF-β and attenuating Smad dependent-TGF-β signaling.