Format

Send to

Choose Destination
Nat Cell Biol. 2001 May;3(5):473-83.

Caveolar endocytosis of simian virus 40 reveals a new two-step vesicular-transport pathway to the ER.

Author information

1
Institute of Biochemistry, Swiss Federal Institute of Technology, Universitaetstrasse 16, CH-8092 Z├╝rich, Switzerland.

Abstract

Simian virus 40 (SV40) is unusual among animal viruses in that it enters cells through caveolae, and the internalized virus accumulates in a smooth endoplasmic reticulum (ER) compartment. Using video-enhanced, dual-colour, live fluorescence microscopy, we show the uptake of individual virus particles in CV-1 cells. After associating with caveolae, SV40 leaves the plasma membrane in small, caveolin-1-containing vesicles. It then enters larger, peripheral organelles with a non-acidic pH. Although rich in caveolin-1, these organelles do not contain markers for endosomes, lysosomes, ER or Golgi, nor do they acquire ligands of clathrin-coated vesicle endocytosis. After several hours in these organelles, SV40 is sorted into tubular, caveolin-free membrane vesicles that move rapidly along microtubules, and is deposited in perinuclear, syntaxin 17-positive, smooth ER organelles. The microtubule-disrupting agent nocodazole inhibits formation and transport of these tubular carriers, and blocks viral infection. Our results demonstrate the existence of a two-step transport pathway from plasma-membrane caveolae, through an intermediate organelle (termed the caveosome), to the ER. This pathway bypasses endosomes and the Golgi complex, and is part of the productive infectious route used by SV40.

Comment in

PMID:
11331875
DOI:
10.1038/35074539
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Nature Publishing Group
Loading ...
Support Center