Cells with too much RCC1 (bottom two cells) are impaired in nuclear import.

Nuclear import is slowed by too much of a good thing. So says a new systems model of nuclear import from Riddick and Macara (page 1027), which predicts that high levels of the cargo carrier Importin-β or the RanGEF RCC1 inhibit import.

With its simple nucleus-versus-cytoplasm architecture, import is a good candidate for systems analysis. Most of the components have been identified, and biochemical experiments have already determined many of the relevant rate constants. Previous models outlined how Ran transport affected steady-state cargo distribution.Now, Riddick and Macara look at the kinetics of cargo import. Their model does what any good model should: it makes unexpected predictions that can be tested experimentally, and it reveals weaknesses in the current understanding of the system.

Surprises came in the form of predictions that...

The Rockefeller University Press
2005
The Rockefeller University Press
2005
You do not currently have access to this content.