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Liposome Model Systems to Study the Endosomal Escape of Cell-Penetrating Peptides: Transport across Phospholipid Membranes Induced by a Proton Gradient

By Fatemeh Madani, Alex Perálvarez-Marín and Astrid Gräslund


Detergent-mediated reconstitution of bacteriorhodopsin (BR) into large unilamellar vesicles (LUVs) was investigated, and the effects were carefully characterized for every step of the procedure. LUVs were prepared by the extrusion method, and their size and stability were examined by dynamic light scattering. BR was incorporated into the LUVs using the detergent-mediated reconstitution method and octyl glucoside (OG) as detergent. The result of measuring pH outside the LUVs suggested that in the presence of light, BR pumps protons from the outside to the inside of the LUVs, creating acidic pH inside the vesicles. LUVs with 20% negatively charged headgroups were used to model endosomes with BR incorporated into the membrane. The fluorescein-labeled cell-penetrating peptide penetratin was entrapped inside these BR-containing LUVs. The light-induced proton pumping activity of BR has allowed us to observe the translocation of fluorescein-labeled penetratin across the vesicle membrane

Topics: Research Article
Publisher: Hindawi Publishing Corporation
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Provided by: PubMed Central

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  1. (1991). A .J o l i o t ,C .P e r n e l l e ,H .D e a g o s t i n i - B a z i n ,a n dA .P r o c h i a n t z , “Antennapedia homeobox peptide regulates neural morphogenesis,”
  2. (1996). Cell internalization of the third helix of the antennapedia homeodomain is receptorindependent,” J o u r n a lo fB i o l o g i c a lC h e m i s t r y ,
  3. (2006). Cell-penetrating peptides—a brief introduction,”
  4. (2005). Cell-penetrating peptides: mechanisms and applications,”
  5. (2004). Cell-penetrating peptides: small from inception to application,”
  6. (2009). Cell-surface accumulation of flock house virus-derived peptide leads to efficient internalization via macropinocytosis,” Molecular Therapy,v o l .
  7. (1994). Chassaing,andA.Prochiantz,“The third helix of the Antennapedia homeodomain translocates through biological membranes,” J o u r n a lo fB i o l o g i c a lC h e m -istry,
  8. (1997). e s ,P .B r o d i n ,a n dB .L e b l e u ,“ At r u n c a t e dH I V - 1T a t protein basic domain rapidly translocates through the plasma membrane and accumulates in the cell nucleus,”
  9. (1974). Isolation of the cell membrane of Halobacterium halobium and its fractionation into red and purple membrane,”
  10. (1988). Mechanisms of membrane protein insertion into liposomes during reconstitution procedures involving the use of detergents. 2.
  11. Modeling the endosomal escape of cell-penetrating peptides: transmembrane pH gradient driven translocation across phospholipid bilayers,” Biochemistry,
  12. Proton transfer reactions across bacteriorhodopsin and along the membrane,”
  13. (1988). r e e na n dP .M .L o e w e n s t e i n ,“ A u t o n o m o u sf u n c t i o n a l domains of chemically synthesized human immunodeficiency virus tat trans-activator protein,”
  14. (2006). Real-time transmembrane translocation of penetratin driven by light-generated proton pumping,”
  15. (1995). Reconstitution of membrane proteins into liposomes: application to energytransducing membrane proteins,”
  16. Rhodopsin-phospholipid reconstitution by dialysis removal of octyl glucoside,”
  17. (1986). Vesicles of variable sizes produced by a rapid extrusion procedure,”
  18. (1991). α-2,8-polysialic acid is the neuronal surface receptor of antennapedia homeobox peptide,”