First published online July 10, 2003
Journal of Cell Science 116, e1602 (2003)
Copyright © 2003 The Company of Biologists Limited
Retrovirus trafficking: gagged and dynein-bound
Once inside cells, intracellular pathogens must hijack cellular machinery
to move around. Listeria, for example, makes use of the actin
cytoskeleton, whereas adenovirus travels on microtubules; vaccinia virus can
do both. So how do retroviruses get about? The foamy virus (a complex animal
retroviruses) has been shown to travel from its site of entry to the nucleus
via microtubule-organizing centres (MTOCs). Ali Saïb and co-workers now
reveal how it does this (see
p. 3433). They
observe that transport of the incoming virus requires microtubules and can be
blocked by a dominant negative inhibitor of the retrograde motor cytoplasmic
dynein. Furthermore, they find that the Gag protein (a structural component of
the viral capsid) is the only viral protein necessary for trafficking, pinning
down the region of the protein responsible to a 30-residue coiled-coil motif
at the N-terminus. The authors then demonstrate that Gag directly interacts
with dynein light chain 8 (LC8) within the dynein motor complex. Finally, they
follow the effect of a Gag point mutant that cannot interact with LC8
(GagL171G) on the viral life cycle, revealing that this interaction is
critical for efficient viral infection. Saïb and co-workers conclude that
the cytoplasmic dynein motor transports foamy virus along microtubules,
speculating that helical coiled-coil motifs similar to that in Gag might be
responsible for interaction of the motor with other cargos.
Related articles in JCS:
- Targeting of incoming retroviral Gag to the centrosome involves a direct interaction with the dynein light chain 8
- Coralie Petit, Marie-Lou Giron, Joelle Tobaly-Tapiero, Patricia Bittoun, Eléonore Real, Yves Jacob, Noël Tordo, Hugues de Thé, and Ali Saïb
JCS 2003 116: 3433-3442.
[Abstract]
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