The role of the nuclear pore complex in adenovirus DNA entry.
Adenovirus targets its genome to the cell nucleus by a multistep process involving endocytosis, membrane penetration and cytoplasmic transport, and finally imports its DNA into the nucleus. Using an immunochemical and biochemical approach combined with inhibitors of nuclear import, we demonstrate that incoming viral DNA and DNA-associated protein VII enter the nucleus via nuclear pore complexes (NPCs). Depletion of calcium from nuclear envelope and endoplasmic reticulum cisternae by ionophores or thapsigargin blocked DNA and protein VII import into the nucleus, but had no effect on virus targeting to NPCs. Calcium-depleted cells were capable of disassembling incoming virus. In contrast, inhibitors of cytosolic O-linked glycoproteins of the NPC blocked virus attachment to the nuclear envelope, capsid disassembly and also nuclear import of protein VII. The data indicate that NPCs have multiple roles in adenovirus entry into cells: they contain a virus-binding and/or dissociation activity and provide a gateway for the incoming DNA genome into the nucleus.
Greber
U F
UF
University of Zurich, Department of Zoology, Winterthurerstrasse 190, 8057 Zurich, Switzerland.
Suomalainen
M
M
Stidwill
R P
RP
Boucke
K
K
Ebersold
M W
MW
Helenius
A
A
D000256:Adenoviridae / Q000235:genetics / Q000502:physiology*; D000906:Antibodies; D001692:Biological Transport / Q000187:drug effects; D002118:Calcium / Q000378:metabolism; D002213:Capsid / Q000378:metabolism; D002467:Cell Nucleus / Q000378:metabolism / Q000821:virology; D004279:DNA, Viral / Q000378:metabolism*; D006367:HeLa Cells; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D009685:Nuclear Envelope / Q000378:metabolism / Q000821:virology*; D015678:Viral Structural Proteins / Q000378:metabolism*; D014909:Wheat Germ Agglutinins / Q000494:pharmacology
D000906:Antibodies; D004279:DNA, Viral; D015678:Viral Structural Proteins; D014909:Wheat Germ Agglutinins; D002118:Calcium