Evidence that membrane transduction of oligoarginine does not require vesicle formation

• Published in: Experimental cell research 2005-07, Vol.307 (1), p.164-173
• Main Authors: Zaro, Jennica L., Shen, Wei-Chiang
• Format: Article
• Language: English
• Subjects: 60 APPLIED LIFE SCIENCES; ACETIC ACID; AIDS VIRUS; Amiloride - pharmacology; AMINES; Ammonium Chloride - pharmacology; AMMONIUM CHLORIDES; Animals; Anti-Bacterial Agents - pharmacology; Arginine - analysis; Arginine - chemistry; Arginine - metabolism; Biological Transport - physiology; BUTANE; Cell Membrane - metabolism; Cell Nucleus - metabolism; Cell-penetrating peptides; CHO Cells; Cricetinae; Cricetulus; Culture Media, Serum-Free - metabolism; Cytoplasmic Vesicles - metabolism; Cytosol - metabolism; DEXTRAN; EDTA; Endocytosis; Endocytosis - drug effects; Endocytosis - physiology; Endosomes - metabolism; ETHYLENE; Filipin - pharmacology; FLUORESCEIN; Fluorescein-5-isothiocyanate; Fluorescent Dyes; FLUORIDES; HAMSTERS; Hydrogen-Ion Concentration; Hydrolysis; Hypertonic Solutions - pharmacology; ISOTHIOCYANATES; Kinetics; LEAD SULFIDES; Lysine - analysis; Lysine - chemistry; Lysine - metabolism; Membrane transduction; Membrane transduction peptides; MICROSTRUCTURE; Oligoarginine; Oligopeptides - genetics; Oligopeptides - metabolism; OVARIES; Peptide Fragments - genetics; Peptide Fragments - metabolism; PEPTIDES; PHOSPHATES; Quantitative measurement; Temperature
• ISSN: 0014-4827; 1090-2422
• DOI: 10.1016/j.yexcr.2005.02.024

The involvement of vesicular formation processes in the membrane transduction and nuclear transport of oligoarginine is currently a subject of controversy. In this report, a novel quantitative method which allows for the selective measurement of membrane transduction excluding concurrent endocytosis was used to determine the effects of temperature, endosomal acidification, endosomolysis, and several known inhibitors of endocytic pathways on the internalization of oligoarginine. The results show that, unlike endocytosis, transduction of oligoarginine was not affected by incubation at 16°C as compared to the 37°C control, and was only partially inhibited at 4°C incubation. Additionally, membrane transduction was not inhibited to the same extent as endocytosis following treatment with ammonium chloride, hypertonic medium, amiloride, or filipin. The endosomolytic activity of oligoarginine was investigated by examining the leakage of FITC-dextran into the cytosolic compartment, which was not higher in the presence of oligoarginine. Furthermore, ammonium chloride showed no effect on the nuclear transport of oligoarginine. The data presented in this report indicate that membrane transduction is likely to occur at the plasma membrane without the formation of membrane vesicles, and the nuclear localization involves membrane transduction, rather than endocytosis of oligoarginine.